**INTERNAL UNOFFICIAL DRAFT - STILL WORK IN PROGRESS - DO NOT
DISTRIBUTE**

**INTERNATIONAL TECHNICAL REVIEW OF STATUS**

**KSTAR PROJECT**

**Coordinated by:**

**Quantum Technology Corp.**

**3650 Wesbrook Mall**

**Vancouver BC V6S 2L2**

**Canada**

**tel: 1-604-222-5539 fax: 1-604-677-5826**

**www . quantum-technology.com**

**Under contract to KOPEC**

**Authors:**

**C. Winter, Ph.D. cwinter@quantum-technology.com**

**J. Miller, Ph.D. miller@magnet.fsu.edu**

**C. Neumeyer,** **M. Sc. neumeyer@pppl.gov**

**S. W. Wolfe, Ph.D. swolfe@quantum-technology.com**

**R. Ivanov, Ph.D. rouslanivanov@yandex.ru**

**J. Montani, B.Eng. jmontani@quantum-technology.com**

**S.I. Choi, M.Sc. sichoi@askcorp.co.kr**

**Date: 2004 Feb. 5**

**[TABLE OF CONTENTS]{.underline}**

**A) Introduction - Scope of Review**

**B) KSTAR Objectives**

**C) KSTAR from an International Perspective**

**D) Component Analysis**

**For each component:**

**- PRESENT STATUS**

**- TECHNICAL RISK FACTORS**

**- COMMENTS AND RECOMMENDATIONS**

**E) Recommendations**

**F) Conclusions**

#  

**A) Introduction - Scope of Review**

This review has concentrated on project management and scheduling
issues. The review was undertaken as part of the procedure of the annual
budget review for the KSTAR project. The review contract is between
Quantum Technology Corp. and KOPEC.

**[Review methodology:]{.underline}** The KSTAR team provided the
reviewers with detailed technical reports on the status of the KSTAR
design, budget and schedule information which were studied by the
reviewers prior to the four-day on-site review. During the on-site
process the review team was able to interview each of the team leaders
and examine documents and test results. The KSTAR team has been very
kind in providing written answers to written questions. The review team
received excellent cooperation and assistance from KSTAR personnel.

The primary objective of the review is to clearly communicate the
present status and expected future program of the KSTAR project to KOPEC
and the Korean Government. The overall results of the review are very
positive.

During the meetings a number of differences between KSTAR procedures and
procedures at other international laboratories were noted. These
differences are commented on in this report. These are positive comments
suggesting minor changes in organizational structure and methodology.
The KSTAR project team is clearly very successful and very effective at
their job.

**B) KSTAR Mission**

The mission of the KSTAR project is to develop a steady-state advanced
superconducting tokamak, and thus to establish the scientific and
technological basis for the construction of a fusion power reactor as an
attractive energy source in the future. This is an important step in the
world-wide fusion energy research program, which aims to find a
practical technical method for controlled exothermic nuclear fusion of
isotopes of hydrogen, as a peaceful carbon-free source of energy with
abundant supply and minimal environmental imact.

The technological aims of the KSTAR project are:

-   To build and operate a fully superconducting magnet system

-   To explore and achieve steady state operation of a tokamak using
    non-inductive current drive

-   To investigate and optimize continuous divertor operation, as well
    as continuous plasma wall interaction. This includes the development
    of limiters, divertor plates and other important in-vessel
    plasma-facing elements.

-   

The research objectives in the context of the KSTAR mission are:

-   To provide tokamak operation in advanced regimes with high-beta
    plasmas such as high performance H-mode, reversed-shear mode, and
    high-l~j~ mode

-   To integrate optimized plasma performance during continuous
    operation, as a step towards an attractive fusion power reactor

-   To extend the present stability and performance boundaries of
    tokamak operation through active control of profiles and energy, and
    particle transport mechanisms.

KSTAR is a very important project for the scientific community as well
as for Korean industry. The project will be the most technically
advanced fusion energy device in the world when it is completed. It is
designed to incorporate the current, most advanced technologies for
plasma confinement, including divertor operation and non-circular plasma
configurations. In addition, the project employs the most up-to-date
plasma heating technologies, such as high power, long pulse RF heating
at ion cyclotron frequencies, electron-cyclotron heating with
state-of-the-art gyrotrons, and powerful neutral beam injection.

**C) KSTAR from an International Perspective**

The KSTAR project will make critical contributions to the world fusion
research and development program. It will:

-   Extend advanced tokamak research to high performance and
    steady-state operating regimes

-   Contribute techniques for successful steady-state operation of the
    international tokamak project, ITER

-   Compare advanced tokamak physics results with those from
    superconducting stellarators and spherical tokamaks.

-   Position Korea to make major contributions to ITER.

None of the other countries involved with ITER have recently
constructed, or are planning to construct, a device with the advanced
ITER-relevant technology of KSTAR.

The KSTAR project is a very ambitious project for Korea given the large
number of new technologies involved. The KSTAR team has already
succeeded in creating the infrastructure \-- scientific and engineering
skills, research facilities, industrial partnerships, university
collaborations and international collaborations \-- required to
successfully complete this project. In addition the KSTAR team deserves
praise and recognition for doing all of this development work with a
severely constrained budget.

The attached table compares the KSTAR project to similar international
projects. Note that KSTAR has the same parameters as the TPX project,
which was planned by the US in the early 1990's but cancelled due to
budget cuts. The key point is that the budget for the KSTAR project is
much less than the proposed budget for TPX. In fact the KSTAR work
breakdown scope budget is only one half of the TPX budget! Furthermore
the KSTAR team has been able to use the budget in a very constructive
manner to establish facilities and research programs for every major
component of the project.

It is our view that the recent cost increases of the KSTAR project as
well as the schedule delays are due to an overly aggressive and
optimistic projection at the start of the KSTAR project. Budget
increases and schedule extensions are necessary at this stage to ensure
the completion of the KSTAR project. This is also essential because it
is part of the infrastructure required for the Korean contribution to
the ITER project.

# **D) COMPONENT ANALYSIS**

(arranged by WBS)

# 

# **[T1 -- TOKAMAK SYSTEMS]{.underline}**

# 

# **[T11 -- Plasma Facing Components]{.underline}**

Consists of:

T111 Divertor

T112 Inboard Limiter

T113 Poloidal Limiter & Armour

T114 Passive Stabiliser

T115 Local Instrumentation & Control

T116 Research & Development

Only the inboard limiter (T112) will be installed for first plasma
experiments, therefore the discussion considers only this component.

### **T112 Inboard Limiter**

## STATUS

Development and design are complete

## TECHNICAL PERFORMANCE

Target performance:

> Ability to withstand the thermal and mechanical loads of high
> temperature fusion grade plasma

Attained performance:

Not yet tested

## TECHNICAL RISKS

1\) Leak in coolant line and loss of coolant

Assessment of risk:

  ---------------- ------------------ --------------- --------------------
  Probability      Consequence        Cost            Schedule implication
                                      implication     

  Low              Delay              Low             Medium
  ---------------- ------------------ --------------- --------------------

Notes:

-   Hydraulic pressure tests to 22 bar are planned

-   Time to install the inboard limiter: 6 months

-   Time to repair a leak: 2 months

2\) Quality of vacuum

> Properties of tile material and wall conditioning affect vacuum
> quality and therefore plasma parameters

Assessment of risk:

  ---------------- ------------------ --------------- --------------------
  Probability      Consequence        Cost            Schedule implication
                                      implication     

  Low              Delay              Very low        Low
  ---------------- ------------------ --------------- --------------------

Notes:

-   The outgassing data for the materials used have all been examined.
    The graphite/CFC was tested for outgassing at the national standards
    institute, due to the fact that the material did not have any
    available outgassing information.

# **[T12 -- Vacuum Vessel System]{.underline}**

**T121 Vacuum Vessel**

**T122 Baking and Cooling Piping System**

## STATUS

T121 Vacuum Vessel Fabrication in progress

T122 Baking and Cooling Piping System Design complete

## TECHNICAL RISKS

1\) Water jacket leak to the vacuum space

Assessment of risk:

+--------------+----------------+-----------------+-------------------+
| Probability  | Consequence    | Cost            | Schedule          |
|              |                | implication     | implication       |
+--------------+----------------+-----------------+-------------------+
| # Low        | Delay at       | Low to medium   | Low to medium     |
|              | worst,         |                 |                   |
|              | performance at |                 |                   |
|              | best           |                 |                   |
+--------------+----------------+-----------------+-------------------+

2\) Piping leak

Assessment of risk:

+--------------+----------------+-----------------+-------------------+
| Probability  | Consequence    | Cost            | Schedule          |
|              |                | implication     | implication       |
+--------------+----------------+-----------------+-------------------+
| # Medium     | Delay at       | Low to medium   | Low to medium     |
|              | worst,         |                 |                   |
|              | performance at |                 |                   |
|              | best           |                 |                   |
+--------------+----------------+-----------------+-------------------+

3\) Vacuum leak

Assessment of risk:

+--------------+----------------+-----------------+-------------------+
| Probability  | Consequence    | Cost            | Schedule          |
|              |                | implication     | implication       |
+--------------+----------------+-----------------+-------------------+
| # Low        | Delay at       | Low to medium   | Low to medium     |
|              | worst,         |                 |                   |
|              | performance at |                 |                   |
|              | best           |                 |                   |
+--------------+----------------+-----------------+-------------------+

**Notes and recommendations:**

-   Implications are different depending on whether a fluid/gas leak is
    to cryostat space or to vacuum vessel space.

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-   Leak specification has been downgraded to 10^-6^ mbar-l/s because
    the original specification was seen to be unnecessarily strict. This
    agrees with our recommendation.

-   The water cooling lines on the vacuum vessel must be helium leak
    tested to ensure there are no leaks. A leak in this location could
    jeopardize the whole project.

-   A leak in the vacuum vessel can be distinguished from a leak in the
    bellows by introducing GHe to the cooling water jacket.

-   The gas and fluid supply penetrations into the vessel, and
    distribution within the vessel, is a complex system. Due to the
    large number of lines and joints, the large thermal gradients,
    stresses, and deflections, as well as the magnetic/eddy current
    forces and deflections, the system is quite challenging from an
    engineering perspective. Also, ease of installation will be a key
    issue, considering the very tight space and limitations of in-vessel
    work. Therefore, this area deserves considerable engineering effort
    and detailing.

## T123 Vacuum Vessel Thermal Shield

## STATUS

Design complete

## TECHNICAL RISKS

1\) Leak in cooling lines

> Assessment of risk:

  --------------- ----------------- ------------------ --------------------
  Probability     Consequence       Cost implication   Schedule implication

  Medium          Performance       Low                Low
  --------------- ----------------- ------------------ --------------------

-   There is a redundant set of GHe cooling lines in the design. To
    switch between sets in the case of a leak takes about one week of
    down time.

2\) Failure of mechanical supports

> Assessment of risk:

  --------------- ----------------- ------------------ --------------------
  Probability     Consequence       Cost implication   Schedule implication

  Low             Delay             Medium             High
  --------------- ----------------- ------------------ --------------------

-   Safety margins in the design of the mechanical mounts must be large
    because replacement is very difficult and the consequences may be
    severe.

3\) Excessive thermal load

> Assessment of risk:

  --------------- ----------------- ------------------ --------------------
  Probability     Consequence       Cost implication   Schedule implication

  Low             Delay             Medium             High
  --------------- ----------------- ------------------ --------------------

# **[T13/T14 − TF/PF Magnet System]{.underline}**

Consists of:

T131/T141 TF/PF Magnet Conductor

T132/T142 TF/PF Magnets

T133/T143 TF/PF Local I&C / External Quench Detection System

T134/T144 TF/PF Magnet Bus & Leads

T135/T145 TF/PF Conductor and Magnet Test

T136/T146 TF/PF Magnet Structure

T137/T147 TF/PF Magnet System Research and Development

# 

# **[T131/T141 -- TF/PF Magnet Conductor]{.underline}**

Production and qualification of CICC conductor for TF and PF magnets,
including: acquisition of superconducting wire (both Nb~3~Sn and NbTi),
plating, cabling, jacketing, and appropriate QA inspections and tests at
each stage.

## STATUS

This task has been carried through the prototype stage and is well into
the production stage. However, it is not clear how thorough the QA test
program is. It has been stated that certified wire test data are
supplied by the vendors, but no such data were readily available showing
scatter and margins relative to the specifications. Apparently, no CICC
current testing has been carried out other than the test of TF00.
Because the test was performed only at approximately 4.5 K, the
critical-current limit of the conductor was not approached. A variety of
CICC inspections and tests are planned, including leak testing prior to
winding and inspection of CICC witness samples reacted along with coils
for evidence of SAGBO. Acceptance criteria for leak test of CICC are
semi-quantitative.

## TECHNICAL PERFORMANCE

The design is based primarily on a minimum critical-current performance
of the wire of 750 A/mm^2^ at 12 T and 4.2 K, and ac-loss performance
defined by dissipation of 250 mJ/cm^3^ of non-copper over a +/- 3T
cycle. It is not clear what are the allowable values for degradation of
that performance in the process of fabricating the wire into a CICC,
winding the coil, and heat-treating in that form.

## TECHNICAL RISKS

1\) A particular batch of wire does not meet specifications

Critical-current or ac-loss performance lower than expectations

Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  Low               Substandard coil  High (replace     Long delay (for
                    performance       coil or operate   replacement) or
                                      at reduced level) none (operate at
                                                        lower level)
  ----------------- ----------------- ----------------- -----------------

2\) Wire damaged or degraded by cabling and/or jacketing

Critical-current or ac-loss performance lower than expectations

> Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  Low               Substandard coil  High (replace     Long delay (for
                    performance       coil or operate   replacement) or
                                      at reduced level) none (operate at
                                                        lower level)
  ----------------- ----------------- ----------------- -----------------

**RECOMMENDATIONS:**

-   Institute tests of wire keyed to production units

-   Institute tests of a reasonable number of CICC samples correlated
    with tests of individual wires. Tests should include CICCs with
    credible flaws that might be introduced by the cabling or jacketing
    processes and be missed during practical inspection procedures. The
    reasonable number should be determined by the observed variability
    of test results among wires and CICCs.

-   Develop suitable methodologies and procedures to ensure strict
    control of materials and processes

# **[T132/142 -- TF and PF Magnets]{.underline}**

Fabrication of TF and PF magnets, including QA inspections and tests

## STATUS

A prototype for the TF coils has been built and tested and a prototype
for the CS and divertor coils has been built (the BKG coil) and will be
tested soon. The outer PF coils are in production.

## TECHNICAL PERFORMANCE

Coils must reach the design field and retain specified performance
margins during all phases of operation. Although complex, these
operating conditions are fully specified. Testing for these margins is
very difficult short of operating the complete magnet system in the
defined operating scenarios.

## TECHNICAL RISKS

1\) A coil fails or exhibits degraded performance

> Coil has a short, has compromised insulation integrity, has degraded
> critical-current performance, or excessive ac loss

Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  Low               All (failure,     High              Extreme delay
                    delay for repair                    
                    or replacement,                     
                    operates with                       
                    degraded                            
                    performance,                        
                    results in damage                   
                    to equipment or                     
                    injury to                           
                    personnel)                          
  ----------------- ----------------- ----------------- -----------------

**RECOMMENDATIONS:**

Either test entire coils (extremely costly and not amenable to fully
measuring true performance margins in many cases) or develop the
appropriate tests of key components (including witness samples of
conductors processed along with coils) that provide confidence in coil
performance.

# Develop suitable methodologies and procedures to ensure strict control of materials and processes 

# **[T134-144 -- TF and PF Magnet Bus-Line and Leads]{.underline}**

This task includes the fabrication and installation of in-cryostat and
out-of-cryostat bus systems, including: joints, bus and joint supports,
feed-throughs, bus ducts, cryogenic current leads, and current lead
boxes.

## STATUS

Several fairly detailed conceptual designs have been produced with
sufficient detail in all components to allow accurate cost projections.
Some components have been prototyped to assess fabrication feasibility,
cool-down, and high-voltage integrity.

## TECHNICAL PERFORMANCE

Buswork and leads must retain specified performance margins during all
phases of operation including normal, off-normal, and fault conditions
of the magnet systems.

## TECHNICAL RISKS

1)  Mechanical/Electrical failure at a joint

> The Bus-Line and the Current leads involve a series of
> strand-to-strand joints, butt joints and lap joints that require care
> and attention to process detail during installation

Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  Low               Failure, Delay    Medium            Medium
  ----------------- ----------------- ----------------- -----------------

## RECOMMENDATIONS

Ensure that processes are well developed, well documented, and
extensively practiced to achieve the required results with very low
probability of error.

# **[T135/145 -- TF and PF Conductor and Magnet Test]{.underline}**

Design and construction of a facility capable of accommodating full-size
prototype and production magnets for test.

## STATUS

Facility completely operational and recently used to test prototype and
production TF coils to high current. Preparations underway to augment
the facility with a BKG coil that is both prototypical of CS coils and
suitable as a facility for testing full-scale conductors to high field
and high current.

## TECHNICAL PERFORMANCE

The facility is capable of cooling down and testing TF coils to nearly
full current, the current level being limited by structural limitations
of the test-coil structure in the single-coil test geometry. The
facility apparently does not have (but could have) provisions for
operating the test coil at a higher temperature, thereby testing to
operating temperature margins for the full system.

## TECHNICAL RISKS

1\) Operating performance margins not fully tested

A variety of manufacturing processes or untested design features could
result in performance margins of completed coils being unacceptable or
lower than expected

Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  Low               Unacceptable or   High (replacement High (replacement
                    lower than        or repair of      or repair of
                    expected          low-performing    low-performing
                    performance       coil)             coil)
  ----------------- ----------------- ----------------- -----------------

# **RECOMMENDATIONS**

-   Provide means of testing superconductor performance margins at an
    acceptably low test current by introducing elevated-temperature
    operation

-   Measure joint resistance accurately, by a method appropriate to the
    allowed resistance.

-   Measure ac losses (combined hysteresis and coupling) by a method
    appropriate to the allowed values.

-   Ensure that analytic models of coil performance are properly
    benchmarked against prototype tests so that the can be relied on to
    predict performance and establish allowable operating limits in full
    scale system

# **[T136/146 -- TF and PF Magnet Structure]{.underline}**

## STATUS

Prototype magnet structures for both TF and outer PF magnets have been
fabricated. The TF magnet structure has been tested for cooling
performance and extensive mechanical tests (static yield and fatigue
crack growth) have been performed on TF case materials. Manufacturing of
four more TF units were begun in January 2004. The first four units will
take one year to complete. Due to budgetary issues, the remaining twelve
TF units will be manufactured over a period of eighteen months after the
first four TF units are completed.

## TECHNICAL PERFORMANCE

Strength of the TF case alloy has been demonstrated in mechanical tests
to be greater than 1000 MPa in comparison to maximum expected stress of
about 500 MPa. Models for demonstrating techniques for cooling-tube
installation show good results. Case cooling tests have been performed
on a model structures with good results.

Manufacturing tolerances on the TF cases provide reasonable margin (5-10
mm) for the fit of TF windings with tolerances obtained there.

Methods of inspection of structures for flaws are under development.

## TECHNICAL RISKS

1\) Leak in the cooling lines

The main concern with the magnet support structure is a leak in the
cooling lines that cool the structure. A leak will deteriorate the
integrity of the vacuum thereby compromising the operation of the
tokamak.

Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  Low               Fail              High              High
  ----------------- ----------------- ----------------- -----------------

# **[T137/147 -- TF and PF Magnet R&D]{.underline}**

# **STATUS**

Complete. See above section T132/T142

> Appendix to TF13/14
>
> Recommended QA/QC measures associated with fabrication, heat
> treatment, and impregnation of a large CICC magnet

-   Visually inspect the CICC to be used for surface imperfections and
    flaws in the conduit

-   Perform helium-gas flow test on the CICC and compare to a standard
    for pressure drop established during the R&D program..

-   Reserve a sample of this CICC and the wire used for its fabrication
    for use as witness samples to be reacted along with the finished
    coil winding

-   Seal the ends of the section of CICC to be wound into the coil and
    leak test in a vacuum chamber with pressurized helium gas inside the
    conduit with a clear and quantitative specification of the tolerable
    leak rate[^1]

(These measures reduce the risk that the investment in fabricated
conductor and coil-winding effort will not be wasted in the event that
an unrepairable leak or flaw is discovered later.)

-   Repeat the leak test (to the appropriate quantitative allowable)
    between each significant fabrication step. Also repeat the flow
    test.

-   During the heat treatment, include witness samples in the
    heat-treatment vessel in a way that ensures that these samples are
    exposed to the same conditions as the coil. For example, the CICC
    witness sample should be exposed to the same external vacuum and
    internal purge gas as the coil.

-   Detailed and continuous data records of heat-treatment conditions
    should be kept. This is especially important, for example, for a
    decision of whether or how to recover from an interruption of the
    heat-treatment cycle.

-   After the heat-treatment process, perform the appropriate tests on
    the witness samples. Ideally, these tests would be performed before
    proceeding to the next step but surely before installing the coil,
    the decision being based on an assessment of cost of the test and
    schedule delays vs risk. At a minimum, the wire should be tested for
    critical current at the appropriate field and temperature and the
    CICC inspected for unexpected and undesirable changes (both outside
    and inside the conduit) that might indicate a problem with the heat
    treatment. It may not be necessary to test the CICC for critical
    current if there have been a sufficient number of tests during the
    R&D program to allow a confident correlation between strand
    performance and CICC appearance.

-   Likewise, if only a visual inspection of the coil terminations is
    possible, there should exist a detailed, well documented process for
    producing such joints that is based on a substantial test program
    during the R&D period. This test program should include a sufficient
    number of tests that the termination and joint performance can be
    related to practical visual inspections with confidence. Based on a
    relative assessment of costs and risks, it may be decided that the
    coil termination and joint processes should, for example, include
    execution and test of a number of trial joints by the installer
    before execution of the real termination and joint on the coil (much
    like qualifying a welder to make a critical, uninspectable weld).

-   After installation of the dry insulation and before the VPI, the
    coil should be electrically tested for turn-to-turn shorts. At a
    minimum a measurement of coil resistance will reveal any serious
    shorts by hidden damage to the insulation or foreign metal shavings,
    for example.

-   After VPI and before putting the coil in a case, repeat the flow
    test and leak test. An electrical test for turn-to-turn shorts is
    also recommended at this time. This is most easily accomplished by
    making the coil the open-circuit secondary of a transformer with a
    separable yoke. The primary may be fed by an ac source with variable
    amplitude. Monitoring the input current and voltage will demonstrate
    the existence or absence of shorts in the secondary with reasonable
    precision.

# **[T17 -- Field Error Compensation (FEC) / Resistive Wall Mode (RWM) Coil System]{.underline}**

# **[T18 -- In-Vessel Control Coil (IVCC) System]{.underline}**

These coils are necessary to improve plasma performance and stability
(FEC/RWM), and to provide control of plasma position.

## STATUS

T17 FEC/RWM Coil System Design in progress

# T18 In-vessel Control Coil System Design complete

## TECHNICAL RISKS

1\) Failure of mechanical supports or coil feedthroughs

Assessment of risk:

  --------------- ----------------- ------------------ --------------------
  Probability     Consequence       Cost implication   Schedule implication

  Very low        Delay             Very low           Very low
  --------------- ----------------- ------------------ --------------------

-   No significant risks identified. These systems are common in all
    tokamaks, and therefore world-wide experience will ensure successful
    implementation.

-   These coil sets are not planned for first plasma. However, position
    control is often useful for reliable, robust first plasma
    experiments, and may improve the scientific value of the first
    campaign, so the IVCC set should be considered at a minimum.

# **[T2 -- AUXILIARY HEATING AND CURRENT DRIVE SYSTEMS]{.underline}**

# 

# 

# **[T22 -- Ion Cyclotron Heating (ICH) / Fast Wave Current Drive (FWCD) System]{.underline}**

Consists of:

> T221 Launchers
>
> T222 Tuning & Matching System
>
> T223 RF Source
>
> T224 ICH Subsystems
>
> T225 ICH Local I&C
>
> T226 ICH R&D

## STATUS

This system is presently under development at KAERI. It is planned for
high performance experiments in the future, and is scheduled to be
complete by 2009.

Overall status:

> Development and design 85% complete
>
> Prototype fabrication 80% complete

## TECHNICAL PERFORMANCE

Target performance:

-   6 MW (4 x 2 MW sources), 25-60 MHz, 20 s pulses, peak voltage \<35
    kV

-   Upgrade planned to 12 MW for 300 s

Present performance:

-   Low power transmitters are presently on hand (300 kW max.) with one
    2 MW source on order.

-   Tests on antenna: 33 kV (peak) (15 kW forward power) for 60 s; 25 kV
    (peak) for 300 s

## TECHNICAL RISKS

The following represent risks to the future experimental campaign and
not to attainment of first plasma.

1\) Loss of coolant in either launcher or transmission line

Assessment of risk:

  --------------- ----------------- ------------------ --------------------
  Probability     Consequence       Cost implication   Schedule implication

  Very low        Delay             Very low           Very low
  --------------- ----------------- ------------------ --------------------

2\) Vacuum feedthrough failure

Assessment of risk:

  --------------- ----------------- ------------------ --------------------
  Probability     Consequence       Cost implication   Schedule implication

  Very low        Delay             Very low           Very low
  --------------- ----------------- ------------------ --------------------

-   Double-redundant ceramic feedthrough has been developed.

# **[T23 -- Lower Hybrid Heating (LHH) / Lower Hybrid Current Drive (LHCD) Systems]{.underline}**

Consists of:

#  T231 LHCD System Design

T232 LHCD Launcher & Splitter

T233 Waveguide Network

T234 Klystron RF System

T235 Klystron Power Supply System

T236 LHCD Local I&C

T237 LHCD R&D

## STATUS

This system is presently under development. It is planned for
high-performance experiments in the future, and is scheduled to be
completed by 2010.

Overall status:

> Engineering design: 50%
>
> Preliminary testing of prototype launcher/splitter has been done.

## TECHNICAL PERFORMANCE

Target performance:

5 GHz, 4 x 500 kW (CW) klystrons (to be developed by Toshiba)

## TECHNICAL RISKS

Risks associated with this system only impact future experimental
campaigns, and not the achievement of first plasma.

1\) Performance does not meet expectations

-   High power, high frequency klystrons are state of the art. There is
    a risk that they will not perform as expected

Assessment of risk:

  --------------- ----------------- ------------------ --------------------
  Probability     Consequence       Cost implication   Schedule implication

  Low             Performance       Low                Very low
  --------------- ----------------- ------------------ --------------------

# **[T24 -- Electron Cyclotron Heating (ECH) / Electron Cyclotron Curren Drive (ECCD) Systems]{.underline}**

# Consisting of:

# T241 Transmission System

T242 Gyrotron System

T243 Gyrotron Power Supply System

T244 ECH Local I&C

T245 ECH R&D

## STATUS

This system will be used both for pre-ionization of the first plasma as
well as for high performance operation in future campaigns.

T241 Transmission System Design complete

> To be manufactured in the US

T242 Gyrotron Manufactured and tested

T243 Gyrotron Power Supply Fabrication complete, testing in progress

## TECHNICAL PERFORMANCE

T242 Gyrotron

Target performance: 0.5 MW at 84 GHz for 2 s

Attained performance: low power testing only

## TECHNICAL RISKS

1\) Performance not sufficient for operation during first plasma
campaign

-   Low power is sufficient for pre-ionization of the first plasma.
    Progress has been good, and the only risk to cost or schedule will
    arise from procurement of the transmission components. The risk to
    cost or schedule is expected to be low.

Assessment of risk:

  --------------- ----------------- ------------------ --------------------
  Probability     Consequence       Cost implication   Schedule implication

  Medium          Performance       Very low           Very low
  --------------- ----------------- ------------------ --------------------

# **[T3 FUELLING AND VACUUM PUMPING SYSTEMS]{.underline}**

## [T31 Fuelling System]{.underline}

Consists of:

T311 Gas Fuel Delivery System

T312 Pellet Fuelling System

T313 Fuelling System Local I&C

T314 Fuelling System R&D

## STATUS 

# Design Phase

## TECHNICAL PERFORMANCE

The maximum fuelling pressure in the vacuum space (hydrogen gas
pressure) is 10^-2^ to 10^-4^ torr with a volume of 55 m^3^. The volume
of hydrogen involved is about one litre.

## TECHNICAL RISK FACTORS

1\) Hydrogen leak

> A hydrogen leak into the building could cause an explosion, which
> might cause damage to the system or pose a hazard to workers.

Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  Low               Safety            Low               Low
  ----------------- ----------------- ----------------- -----------------

**RECOMMENDATION:**

Hydrogen safety should be included in all discussions involving overall
plant safety. See also recommendations in WBS T82.

**[T32 Vacuum Pumping System]{.underline}**

Consists of:

> T321 Torus Pumping System

#  T322 Cryostat Pumping System

T323 Roughing & Backing System

T324 Diagnostics Vacuum Pumping Interface

T325 Leak Detection Systems

> T326 Vacuum Pumping System I&C

The pumping system includes two separate pumping systems, each with an
RGA, a vacuum pump, a cryopump, and a leak detector.

## STATUS 

Design Phase

## TECHNICAL PERFORMANCE

In the event of a hydrogen explosion, the exhaust pipes have been
specified to have a wall thickness of 4 mm.

## TECHNICAL RISK

1\) Hydrogen Explosion

Main technical risk is a danger of having hydrogen gas at the outlet of
the vacuum pump (1 bar). There is also a fear of H~2~ contamination of
the oil of the pumps.

Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  Low               Safety            Low               Low
  ----------------- ----------------- ----------------- -----------------

# **[T33 Wall Conditioning System]{.underline}**

# 

# Consists of:

# T331 Discharge Cleaning System

T332 Wall Coating System

#  T333 Wall Conditioning System I&C

#  T334 Wall Conditioning System R&D

## STATUS 

Design Phase

## TECHNICAL PERFORMANCE

The vacuum vessel and inside components should have a surface state that
minimizes the amount of foreign material in the plasma due to
interaction between the plasma and the wall. Wall conditioning in KSTAR
will be performed using glow discharge cleaning. Effective impurity
removal is possible when the discharge current is more than 0.1 A/m^2^.
Assuming the discharging area is 300 m^2^, a discharging current of more
than 30 A is required. Discharge electrodes are mounted in two ports
(Bay A, Bay I), which are separated by 180° on the torus. The discharge
power supply has a capacity of more than 20 kW. Hydrogen is the
discharge gas for impurity removal, and helium gas is used for fuel gas
desorption. Proper discharge pressure is several mTorr.

## TECHNICAL RISK

1\) Poor vacuum

Wall conditioning is essential for good plasma and its purpose is to
remove foreign materials on the inner wall and outgassing of the surface
materials. If the wall conditioning is poor the vacuum integrity may be
compromised.

Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  Low               Performance       Low               Low
  ----------------- ----------------- ----------------- -----------------

**[T4 Power Systems]{.underline}**

The following information is based on the documents supplied for this
review (originating late 2003) and other information and documents
received by the writer during prior reviews, including the Magnet &
Power Supply Review of October 2002.

The latest KSTAR power supply scheme is summarized in the table below.

  ----------- --------------- ------- ------- ------- ---------- ---------- -------- ------
  System      Type            Vramp   Vflat   Imax    Polarity   Units      Quench   Blip

  TF          IGBT            20V     20V     40kA    Unipolar   1          yes      no

  PF1,2,7     Thyristor       1800V   360V    25kA    Bipolar    3          yes      yes

  PF3,4,5,6   Thyristor       1800V   360V    25kA    Bipolar    8(4U,4L)   yes      yes

  FEC         IGBT/IGCT/GTO   50V     50V     7kA     Unipolar   2(mid,     no       no
                                                                 sad)                

  ICC         IGBT/IGCT/GTO   900V    900V    7.5kA   Bipolar    2(V,R)     no       no
  ----------- --------------- ------- ------- ------- ---------- ---------- -------- ------

For first plasma the required systems are TF, PF 1,2,7, and PF3U, PF3L,
4L, 5L, 6L, where U=upper and L=lower. Because the first plasma
operations will be in the double null configuration, separate control of
the upper and lower coil pairs is assumed not required, so the
deployment of the outer coil power supplies 4U, 5U, and 6U has been
deferred. Whether or not plasma initiation field null conditions can be
achieved, and whether or not vertical stability can be maintained
without a radial field component (which would be produced by having
upper current not equal to lower current in one or more circuits) has
not been assessed by the writer.

For quench protection, the plan is to use a two-stage
mechanical-thyristor switch (MTS) scheme in series with a redundant
back-up DC circuit breaker (DCCB). The MTS involves the commutation of
the load current by discharging a capacitor through a thyristor, which
creates an artificial current zero in a parallel vacuum circuit breaker
and/or mechanical bypass switch. The MTS scheme is essentially the same
as that developed by the Efremov Institute for the ITER power supplies.
The technology choice for the redundant back-up DCCB has not been
finalized as of yet. The candidates are an explosively actuated DCCB
such as the one developed by Efremov for ITER, and a "Pyristor"
consisting of a circuit breaker in parallel with a fuse, such as that
manufactured by the Ferraz Corporation in France. The former is less
complex and therefore less likely to fail than the latter. However, the
former is a unique item not commercially available.

For first plasma the electric power demand can be met by the local grid,
so that no supplemental source is required. However, the project plans
to install a Motor-Generator (MG) set later on for this purpose.

**STATUS**

Fabrication of the TF power supply is complete, and it has been in use
for some time already in the prototype TF magnet testing. This includes
the quench protection, although not with the redundant back-up DCCB, and
not with the final dump resistor module. While the writer does not
consider the power electronic topology chosen for the the TF (AC/DC
converter feeding IGBT DC/AC inverter, feeding DC rectifier) to be
optimal in terms of cost or efficiency, it will nevertheless function in
a satisfactory way as already demonstrated. In addition, it gives Korean
industry some experience with the high current IGBT inverter.

The PF3U fabrication is complete. Some testing has already been
performed with the ramping power supply driving a copper magnet. The
complete power supply will be tested using a superconducting PF coil
sometime in the near future. Additional testing has been performed on
prototype PF quench protection circuits and other accessories such as
the DC current transducers (new to Korean industry).

Less progress is evident in the area of the Field Error Correction (FEC)
and Internal Control Coil (ICC) power supplies. These will be of the
"switched mode" variety, using IGBTs, IGCTs, or GTOs. However, since
these systems are not needed for first plasma, and are less critical in
general, their present status is not cause for concern.

The remainder of the first plasma power supply systems are to be
fabricated by POSCON and completed by the end of 2005. The full year in
2006 is allocated to the installation and commissioning. This was
communicated verbally, and is consistent with schedules shown in October
2002. However, the schedule included with the documentation package for
this review showed some of the fabrications not ending until mid-2006.

During various reviews, including this one, various one-line diagrams,
schematics, and control wiring diagrams have been presented and included
in the documentation. However, the writer has never seen evidence of a
fully integrated design that covers all details and which is sufficient
to procure, fabricate, install, and commission the entire electrical
power system. It should be pointed out that this is no small
undertaking, requiring a large number (perhaps of order 1000) of
drawings. Based on the telephone conference of February 2, 2004, the
intent is to complete the integrated design by the end of this year
(2004), including the final selection of items such as the redundant
DCCB technology.

## TECHNICAL RISKS

1\) Power Electronics Systems

Although the advanced power electronics systems are beyond the current
state of the art for Korean industry, they do not exceed the technology
of other systems built at other facilities in the US, Europe, and Japan
in the past two decades. The Koreans have been very proactive in
performing R&D to develop their domestic capabilities in the high
voltage, high current, high power regime of power electronics. In doing
so they have no doubt gained lots of experience which will be invaluable
when it comes time to commission the full system. And the prototype
testing which they have performed will significantly mitigate these
risks.

Assessment of risk:

+-----------------+-----------------+-----------------+-----------------+
| Probability     | Consequence     | Cost            | Schedule        |
|                 |                 | implication     | implication     |
+-----------------+-----------------+-----------------+-----------------+
| Low             | Reduced         | Medium          | #### Medium     |
|                 | Performance     |                 |                 |
+-----------------+-----------------+-----------------+-----------------+

2\) Control and Protection Systems

The fully integrated design must address control and protection. There
is evidence of good work in these areas, but the design will continue to
evolve as the time of power supply and machine commissioning approaches.
The protection issue will be very challenging and absolutely critical
because of the superconducting coils. Ground fault and quench detection
design details must be developed, and the fault response of the power
supplies to internal and external faults must be coordinated.
Reliability will be a crucial issue. The essential element, in the end,
is the redundant back-up DC Circuit Breaker. The technology choice needs
to be finalized, and if necessary, tested to fully characterize it. The
overall coil fault detection and protection system should utilize
Failure Mode and Effects Analysis (FMEA).

Assessment of risk:

+-----------------+-----------------+-----------------+-----------------+
| Probability     | Consequence     | Cost            | Schedule        |
|                 |                 | implication     | implication     |
+-----------------+-----------------+-----------------+-----------------+
| Low             | Magnet Failure  | High            | #### High       |
+-----------------+-----------------+-----------------+-----------------+

3\) Cost, Schedule, and Technical Performance

Success in the end will depend on a sound and well-documented integrated
system design that can be efficiently installed and commissioned in the
field. The actual time and resources required to complete the work can
be guessed or estimated based on a top-down view, but the bottom-up
estimate can only be generated once the integrated design is in place.
Although not reviewed by the writer, there is evidence that progress is
being made toward the finalization of the integrated design, which was
projected to be completed by the end of this year.

Assessment of risk:

+-----------------+-----------------+-----------------+-----------------+
| Probability     | Consequence     | Cost            | Schedule        |
|                 |                 | implication     | implication     |
+-----------------+-----------------+-----------------+-----------------+
| Medium          | Delay and/or    | Medium          | #### Medium     |
|                 | overrun         |                 |                 |
+-----------------+-----------------+-----------------+-----------------+

4\) Commissioning and Integrated System Testing

The integrated magnet and power supply system, along with its control
and protection, is a complex and critical system. Detailed plans and
procedures need to be developed to guide in the commissioning of its
component parts, and then the integrated system. This must include
suitable engineering instrumentation so that it can be confirmed that
the systems are performing as expected as the operating levels are
increased.

Assessment of risk:

+-----------------+-----------------+-----------------+-----------------+
| Probability     | Consequence     | Cost            | Schedule        |
|                 |                 | implication     | implication     |
+-----------------+-----------------+-----------------+-----------------+
| Medium          | Delay and/or    | Medium          | #### Medium     |
|                 | Equipment       |                 |                 |
|                 | Damage          |                 |                 |
+-----------------+-----------------+-----------------+-----------------+

**[T5 Diagnostic Systems]{.underline}**

## STATUS

Design phase

**Recommendations:**

DIAGNOSTICS FOR THE FIRST PLASMA (The basic minimum)

  -------------- ------------------- -------------- -------------- ---------------
  PLASMA         EQUIPMENT           TIME NEEDED    NUMBER OF      COMMENTS
  PARAMETER                          FOR            PEOPLE NEEDED  
                                     DEVELOPMENT    FOR            
                                                    DEVELOPMENT    

  Plasma current Rogowski coil       2yr            1/3            Note 1

  Loop Voltage   Flux loops          2yr            1/3            Notes 1,2

  Plasma shift   Magnetic probes     2yr            1/3            Notes 1, 2

  Control of     In-vessel control   1 yr           1 physicist, 1 Modern
  plasma         coils+ magnetic                    EE, 1 computer distributed
  position       probes+ distributed                engineer       digital control
                 digital computer                                  system to be
                 feed back system                                  developed which
                                                                   can evolve over
                                                                   the life of the
                                                                   project

  Average plama  Mm microwave        12 months      1              
  density        interferometer                                    

  Control of     Gas-puffing         12 months      1              
  plasma density system + feed-back                                
  and its time   of                                                
  evolution      MW-interferometer                                 

  Electron       Thomson scattering  24-36 months   1-2            Manufacturing
  temperature on of laser beam                                     of simulating
  the axis                                                         sector of VV
                                                                   will be helpful

  Plasma TV      High Speed CCD      3 months       1              
                 Video                                             
  -------------- ------------------- -------------- -------------- ---------------

1.  Location, mounting, routing of leads, and feedthroughs are critical

2.  In-vessel diagnostics are custom subminiature magnetic probes which
    must operate at very high temperatures and require high temperature
    insulated wire

3.  Because of difficulty of access, in-vessel diagnostics sufficient
    for operations beyond first plasma should be included in initial
    installtion prior to first plasma; they should not be deferred

##  T51 Magnetic Measurement Diagnostics

Consists of:

T511 Rogowski Coils

T512 Flux / Voltage Loop

T513 Magnetic Field Probe

T514 Saddle / Locked-mode Coils

T515 Mirnov Coils

T516 Diamagnetic Loops

T517 Vessel Structure Current Monitor

The set of Magnetic Measurement Diagnostics (MMD) includes sensors for
measurements of poloidal magnetic flux, loop voltage, local magnetic
field, B-fluctuations, diamagnetic flux, vessel current, halo current,
etc. This set of diagnostics is quite complete and sufficient both for
efficient operation of the tokamak and for evaluation of plasma
parameters.

These diagnostics are included in the basic set required for the first
plasma operation.

**STATUS**

The MMD systems are 55-60% complete as reported on 2003.4.1-10.30. This
status is quite satisfactory for future implementation and use during
the first plasma experiments. The design and testing of the prototype is
satisfactory.

## TECHNICAL RISK FACTORS

1)  Damage to sensors during operation

The technical risks in this part of the project are related to possible
damages to the sensors after the vacuum vessel is closed. Damage to some
of these sensors, for example the Rogowski coil, might produce serious
problems for the tokamak\'s operation. Because of the relatively low
price, the number of magnetic probes should be doubled (so that there
are duplicates).

Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  Medium chance     Performance, Fail High              High
  that a sensor may                                     
  fail, however,                                        
  redundancy avoids                                     
  system failure                                        
  ----------------- ----------------- ----------------- -----------------

# **T52 Control and Machine Diagnostics**

Consists of:

> T521 mm-Wave Interferometer
>
> T522 Hard X-ray Detector
>
> T523 Survey IR TV
>
> T524 Divertor Protection IR TV
>
> T525 Reciprocating Langmuir Probe
>
> T526 Edge Probes (Movable)
>
> T527 Fixed Langmuir Probe Array

The Control and Machine Diagnostics (CMD) consist of a millimeter-wave
interferometer, Hard X-ray detector, Survey IR TV, Diverter Protection
IR TV, Reciprocating Langmuir probes, movable Edge probes, and Fixed
Langmuir Probes array. This set of diagnostics, combined with the
magnetic measurement diagnostics, is sufficient for control of the
machine operation.

## STATUS

The present status of CMD as reported on 2003.4.1-2003.10.30 is
satisfactory. The systems are 30-65% complete and there is enough time
left to finish their development and installation before the plasma
operation starts.

## TECHNICAL RISK FACTORS

1)  Sensor damage

> The technical risk of a failure is quite different for each of these
> diagnostics. The highest risk of damage is caused by having the
> Langmuir probes both movable and rigid. These probes are located
> inside the vacuum vessel and contact the plasma, so fixing and/or
> replacing them might be problematic in many cases. There is also a
> large risk that the plasma will be contaminated during reciprocating
> and movable probe operation if the probes are damaged.

Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  Medium            Performance, Fail High              High
  ----------------- ----------------- ----------------- -----------------

## RECOMMENDATIONS

Since the electric probe measurements at the edge of the plasma are most
valuable for fine investigations in well organized plasma, these
diagnostics are not recommended for the first plasma experiments. All
the other diagnostics are located outside the Tokamak and can easily be
repaired or replaced.

The millimeter-wave interferometer is one of the main diagnostics,
capable of provide basic information about the first plasma. The
unavailability of this diagnostic at first plasma experiments would make
the interpretation of results problematic. This diagnostic system was
reported as being 65% complete, but no detailed information concerning
the status of the development was found. High management attention to
this diagnostic is recommended, in order to make it available in the
first plasma experiments.

##  T53 Vacuum Diagnostics

Consists of:

T531 Torus Ion Gauges

T532 Residual Gas Analyzer

T533 Inspection Illuminator

T534 Fast Neutral Pressure Gauges

The list of vacuum diagnostics includes torus ion gauges, residual gas

analyzer, inspection illuminator, and fast neutral gas gauges, but there
is information available regarding the inspection illuminator only.

## TECHNICAL RISK FACTORS

The technical risk related to these elements of vacuum diagnostics is
low.

## T54 Passive Visible / IR Diagnostics

Consists of:

T541 Visible Survey Spectrometer

T542 H_alpha Monitor

T543 Visible Bremsstrahlung Array

T544 Visible / H_alpha TV

T545 Diverter Visible / H_alpha TV

T546 Multichord Visible Spectrometer

T547 Visible Filterscopes

T55 Passive UV / X-ray Diagnostics

The set of passive visible / IR Diagnostics consists of Visible Survey
spectrometer, H-alpha monitor, Visible Bremsstrahlung Array, Visible/
H-alpha TV, Multichord visible Spectrometer, and Visible filterscopes.

**STATUS**

The reported completeness is 80-85%, and the design, development and
tests are quite satisfactory.

## TECHNICAL RISK FACTORS

> The risks may be related to possible vacuum leaks or damages to the
> view ports, however, the technical risks for the project are low.

**T55 Passive UV/ X-Ray Diagnostics**

Consists of:

T551 X-ray Crystal Spectrometer

T552 Soft X-ray Array

T553 X-ray Pinhole Camera

T554 X-ray Pulse Height Analyzer

T555 Soft X-ray Spectrometer

T556 VUV Survey Spectrometer

T557 Diverter VUV Spectrometer

T558 Bolometer Arrays

T559 Diverter Bolometer Arrays

## STATUS

The development, fabrication and testing of the X-ray crystal
spectrometer and soft X-ray array is a well advanced part of the KSTAR
diagnostics. A part of the equipment has been successfully tested in
different Tokamak experiments. The reported completeness of these
diagnistics is over 60%.

## TECHNICAL RISK FACTORS

> The risks may be related to possible vacuum leaks or damages to the
> view ports, however, the technical risks for the project are low.

##  T56 Active Laser Diagnostics

Consists of:

T561 Thomson Scattering (Core, Edge)

T562 Diverter Thomson Scattering

T563 Vertical FIR Interferometer

T564 Tangential FIR Interferometer / Polarimeter

T565 Laser Induced Fluorescence (LIF)

##  T57 Active Beam Diagnostics

Consists of:

T571 Charge Exchange Spectroscopy

T572 Motional Stark Effect

T573 Poloidal Rotation CES

T574 Beam Emission Spectroscopy

T575 Diagnostic Neutral Beam

T576 Impurity Pellet Injector

##  T58 Microwave Diagnostics

Consists of

T581 ECE Heterodyne Radiometer

T582 ECE Grating Polychromater

T583 Diverter Microwave Interferometer

T584 Edge Reflectometer

T585 Microwave Imaging Reflectometer

T586 ECE Imaging System

T587 Electron Cyclotron Absorption (ECA)

##  T59 Particle Measurement Diagnostics

Consists of:

T591 Epithermal Neutron Detectors

T592 Multichannel Neutron Collimator

T593 Neutron Fluctuation Detector

T594 Escaping Fast-ion Detector

T595 Charge Exchange Neutral Analyzer

**[T6 Control and Data Systems]{.underline}**

## T61 Tokamak Control System

Consists of:

T611 Central Control System

T612 Main Operation Console

T613 Computer System

T614 Interlock & Safety System

T615 Remote Collaboration System

T616 Tokamak Control System R&D

**STATUS:**

Procurement stage

International design of the central control system is complete. The
central control system is now in the procurement stage. The Main
Operation Console Design concept has been approved by General Atomic.
The Interface and network research and development is also 100%
complete.

## TECHNICAL RISK FACTORS

1\) Functional Failure:

> The main technical risk factor is if the control system fails to
> perform its required functions. With careful programming,esting, and
> the inherent flexibility of the computer-based control this risk is
> extremely low. The following principles shall be followed in this
> regard:

-   the overarching philosophy shall dictate that protection systems
    local to the controlled equipment (e.g. power supply systems,
    heating systems, etc.) should be self-sufficient such that no
    failure or misoperation of the central control system can endanger
    the controlled equipment or the KSTAR device. The central control
    system shall not be responsible for protection functions.

-   

-   \- to enhance the reliability and security of the computer-based
    control, all engineering control systems shall be isolated from
    outside networks by suitable firewall systems

##  T62 Plasma Control System

Consists of:

T621 Magnetics Control System

T622 Kinetics Control System

T623 Discharge Supervisory Control System & Interface

T624 Plasma Control System R&D

**STATUS:**

Design Phase

General Atomic has approved the concept design so the system is now in
the design phase

## TECHNICAL RISK FACTORS

1\) Functional Failure

> The main technical risk factor is if the control system fails to do
> its designed task. With careful programming and testing this risk is
> extremely low.

##  T63 Machine Interface & Network System

Consists of:

T631 Bus Assembly

T632 Closed Local Area Network

T633 Open Local Area Network

T634 Network Management System

T635 Interface & Network R&D

## STATUS

. The Interface and Network research and development is now 100%
complete.

## TECHNICAL RISK FACTORS

1)  Functional Failure

> The main technical risk factor is if the control system fails to do
> its designed task. With careful programming and testing this risk is
> extremely low.

##  T64 Data Acquisition System

Consists of:

T641 Database System

T642 Data Acquisition Hardware

T643 Local Data Access & Control System

T644 Data Analysis Software

T645 Data Acquisition System R&D

# **[T7 System Integration]{.underline}**

# 

# **T72 -- TOKAMAK Assembly**

1\) Assembly of KSTAR Main System

2\) Interface of Subsystems for Main System

3\) Precise measurement & Adjustment of KSTAR Main system

### **STATUS**

The KSTAR team has done an excellent job of planning a detailed assembly
sequence. This includes a 3-D visual simulation of the assembly.

### **TECHNICAL RISKS**

1\) Interference between systems installed. Only minor delays
anticipated.

Disassembly/reassembly time due to any magnet fault :

TF coil takes, 17 months to disassemble and reassemble in the event of
requiring an upgrade.

Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  Medium            High              High              17 months
  ----------------- ----------------- ----------------- -----------------

**[T8 - Project Management and Interface Control]{.underline}**

## T81 - Project Control and Support

The KSTAR project is divided into areas of responsibility according to
physical components of the machine. Team leaders are responsible for
specific Work Breakdown Scope (WBS) (T- numbers) or specific Facility
(F-numbers) sections. Each team leader manages his own part of the
project and is responsible for his own budget.

The use of conventional project management tools is inconsistent across
the various WBS sections.

**RECOMMENDATIONS**

1\) The KSTAR team could consider implementing a standardized project
management reporting structure. Such a structure could include:

i\) A construction project manager with overall responsibility for
construction and commissioning of all systems required for first plasma;

ii\) Regular periodic reports from each section to the project manager;

iii\) Regular updating of the schedule producing Critical Path and/or
Gantt charts;

iv\) Regular updating of the financial status, including for each
sector: requested budget, approved budget, expended,
committed/encumbered, available funds at present, planned future funds,
and computing "earned value" (i.e. "Budgeted Cost of Work Performed"
(BCWP), "Actual Cost of Work Performed" (ACWP), "Budgeted Cost of Work
Scheduled" (BCWS), "Actual Cost of Work Scheduled" (ACWS);

v\) Regular reporting by the construction project manager to all team
leaders of current status and planned activities for the next period;

vi\) Project critical fault analysis done on a project-wide basis based
on a probabilistic/deterministic method to list possible faults,
identify their consequences, identify systems which can reduce the harm
to the project of these faults and to allocate funding or effort
accordingly;

vii\) Consistent quality assurance/quality control system (QA/QC) such
as 6-sigma measurements of critical component parameters and tracking of
those critical components.

This recommendation should not be taken to mean that the review found
any problem with the existing project management, simply that that
because of inconsistent methods used by the different WBS teams it is
difficult for the reviewers to review the overall project planning
process.

2\) The KSTAR team considered a critical project fault analysis of all
fault scenarios which substantially affect the project schedule or
performance, such as a "Failure Modes and Effects Analysis" (FMEA). This
should identify and list significant faults, calculate probability of
the fault, evaluate cost and schedule delay for the fault, and discuss
strategies to avoid the fault within reasonable cost.

Special attention should be made of: helium leaks into the cryostat
space, issues such as joints and heat treatment which may affect maximum
magnetic field achievable and magnet fault detection and quench
protection which are necessary for magnet safety.

superconducting magnet performance.

For example: (the numbers are for example illustration only, not
calculated)

Project critical fault scenario: Flexible helium cooling hoses on the
heat shield of the vacuum vessel may pass initial leak test, but leak
after repeated bending.

Cost to repair: eg. Won 500,000,000

Schedule delay: eg. 1 month

QA/QC to reduce the probability:

100% test of bellows sections without stress.

100% test of bellows sections while flexing up and down to elastic limit

20% cold test of bellows at LN2 temperature

6 sigma destructive testing of burst pressure of bellows hose based on
10 qualification samples and 10 random samples from delivered sections

Cost of QA/QC program: eg Won 3,000,000

or

Design change to reduce the probability

Replace flexible bellows hose with double walled flexible bellows hose

Cost increase of Won 10,000,000

or

Replace flexible bellows hose with a loop of pre-tested seamless
stainless tubing which has enough flexibility

Cost decrease of Won -10,000,000 (reduces cost)

## T82 Project Safety

T82a Radiation Safety, meeting with Dr. Kim Chang Seok February 4,
2004@10:45AM

The reviewers met with Dr. Kim, Chang-Seok, who is the radiation safety
officer for the KSTAR project.

### **STATUS**

An application has been submitted to the Korean authorities for a
nuclear facility operating license. This license is required before the
first plasma. It is anticipated that the license may be approved
mid-2004.

The reviewers were not permitted to examine the license application,
however they were assured that it includes:

\* Radiation dosimeters for personnel

\* Safety interlocks to prevent operation when personnel are in the
room,

\* Shielding (1.2 meters of concrete) around the facility,

\* Procedure for waiting a few hours before allowing re-entry to reduce
personel exposure to materials activated by radiation,

-   Report is in preliminary stage and is not available for viewing.

-   Dr. Kim submits regular reports to the Korean nuclear safety
    governing body.

-   KSTAR must get licensing to operate nuclear machine.

-   The license will be available by this summer 2004.

-   The schedule is covered in the Power Point presentation.

-   Half of the budget has been spent to date.

-   He is responsible for all of the radiation safety concerns for the
    new system.

-   The budget for safety programs is around 3 million dollars.

-   1.2 m wall thickness for the walls of the main chamber.

**Work in progress:**

A decommissioning plan is being prepared and should be complete this
year.

Design of the safety interlock systems is in progress.

### **TECHNICAL RISKS**

1\) Radiation Safety

X-ray exposure from high voltage discharges such as the Neutral Beam
Injection,

Neutron exposure from nuclear reactions such as the Neutral Beam
Injection

Activation, exposure from previously non-radioactive materials which
become radioactive after exposure to radiation from the KSTAR nuclear
reactions,

Exposure to radiation while KSTAR is operating, contamination exposure
by absorbing activated materials including solids, liquids and gases,
and other radiation hazards.

Assessment of risk:

  ----------------- ----------------- ----------------- -----------------
  Probability       Consequence       Cost implication  Schedule
                                                        implication

  High              Safety            Low               Low
  ----------------- ----------------- ----------------- -----------------

Radiation shielding and radiation protection program

As soon as the NBI facilities are implemented in the KSTAR project,
induced radiation will emerge as a new factor of tokamak operation. No
access into the entire tokamak area will be possible during the 5 -- 10
hours after NBI-heated operation, and work on many components of
diagnostic equipment will be restricted. Other Tokamaks have radiation
shielding be built close to the tokamak facility and NB-injectors to
avoid this issue. KSTAR has chosen simply to wait for deactivation.

Qualified special personnel and appropriate equipment will be needed to
provide a radiation safety program.

Comment:

In the case of Neutral Beam Injection, the researchers were not able to
provide a radiation survey or radiation safety document. Due to high
currents there may be intense beams of X-rays leaking from the vessel
ports or penetrating through the walls. The KSTAR radiation-safety
officer claims this is not his scope of responsibility because it is off
site at Korea Atomic Energy Research Institute.

However, because this is a safety issue, the reviewers feel that the
KSTAR radiation-safety officer should receive a safety review report
from all KSTAR activities, whether on site or off site. The KAERI staff
will do a study and prepare a report.

2\) Electrical Safety

The use of high voltage, high current, high power, and high stored
energy equipment is an inherent aspect of any magnetic fusion facility.
Safe conduct of commissioning, operation, and maintenance requires the
incorporation of sufficient design features to ensure that personnel are
isolated from these hazards under all circumstances, that all activities
are conducted per written procedures, and that all personnel are
adequately trained. At the present stage the emphasis should ensure that
the design includes sufficient isolating and grounding devices,
electrical and mechanical interlocks, energy absorbing barriers and
isolation features such that personnel safety can be ensured during all
commissioning, operation and maintenance.

# 23 Non-radiation Safety

The review committee was unable to identify one person who has overall
responsibility for Non-radiation safety issues for the KSTAR project.
This may be a serious issue for the organizational structure, because
some safety issues may \"fall through the cracks\" between different
groups. The review committee was unable to obtain a list of
non-radiation safety issues for the KSTAR project. Clearly for such a
complex project safety reports and formal committee safety reviews
should be implemented.

The US Department of Energy has published a relevant guide, "Safety of
Magnetic Fusion Facilities: Requirements," DOE-STD-6002-96, May 1996
that addresses the diverse issues for safety in such a facility.

In the case of the Brookhaven National Laboratory (BNL), New York USA,
there are published safety standards available on their web site for a
wide variety of issues. There is a formal procedure that does not allow
any equipment to be operated without a formal safety committee review.
After operation the users must still report to the safety committee. The
safety group performs spot safety checks of each team every year.

Some of the non-radiation safety issues applicable to KSTAR are:

Low oxygen deficiency (use sensors, alarms, fans - see BNL standard)

High magnetic field (use fence, warning signs - see BNL standard)

Windows into vacuum space (do critical failure analysis - see BNL
standard)

Electrical equipment (see Korean standard, UL, CE or CSA standards)

High voltage equipment (wire cage fence, safety interlocks, formal
safety committee review, see BNL standard)

Hydrogen gas fire/explosion (use fans, sensors, flash back preventors on
vent pipes, see pressurized gas standard, BNL standards)

Assessment of risk:

+-----------------+-----------------+-----------------+-----------------+
| Probability     | Consequence     | Cost            | Schedule        |
|                 |                 | implication     | implication     |
+-----------------+-----------------+-----------------+-----------------+
| High            | Safety          | Low             | #### Low        |
+-----------------+-----------------+-----------------+-----------------+

**[T83 Project Physics and Modeling: Not reviewed.]{.underline}**

## [T84 Facility Construction Interface]{.underline}

Items that are part of the KSTAR machine are assigned T-numbers (WBS)
and are part of the KSTAR budget.

Items that are not part of the KSTAR machine are assigned F-numbers and
are part of the FACILITY budget.

KSTAR did not provide the review team with a document defining the
delimitation of the scope of supply between these two systems. In many
cases it is reasonably clear from the definitions. In the case of the
cryogenic facilities the boundary is the cryostat boundary.

**FACILITIES (F numbers not in T number system)**

**CRYOGENIC FACILITIES**

The cryogenic facility is now in the detailed design phase with a
contract through Samsung and Air Liquide.

-   This process involves re-estimating the heat loads of the entire
    KSTAR system. At this time these heat loads are still subject to
    uncertainty. The results of this analysis are expected in 2004.

-   The vacuum vessel of KSTAR, and consequently the cryostat as well,
    is designed to have 120 diagnostic and technological ports. Such a
    large quantity of ports increases the hot area in the cryostat from
    40 square meters (vacuum vessel itself) to 120 square meters, thus
    considerably increasing the inward heat flux and therefore the
    consumption of liquid helium. There is a non-negligible risk that
    the cool-down and operation of the superconducting-magnet system
    will not be achieved in this cryostat with the presently specified
    refrigeration system. Additional detailed and expert study of the
    cryostat is strongly recommended prior to the start of assembly of
    the facility.

-   

-   **ELECTRIC POWER SUPPLY**

-   

-   An electric power supply system that is able to provide the KSTAR
    facility with its required peak power is planned. This system will
    eventually utilize an energy-storage device (a motor-generator) to
    cover power peaks that occur during NBI, ECRH, and ICRH operations.
    While an MG system has been envisioned and planned, it is a very
    long-lead item. This factor needs to be taken into account in the
    planning of the research program after first plasma and initial
    operating campaign.

**General Recommendations:**

A. The efforts and financial support should be concentrated on first
priority aims.

1.  The first priority, in the current state of the project, is to
    supply KSTAR with appropriate superconducting coils. This is also
    the most critical part of the whole project. It is the
    superconducting TF and PF magnet systems that make KSTAR unique in
    the world fusion program. On the other hand, the future operation of
    KSTAR with magnetic fields considerably lower than expected, would
    strongly reduce the scientific and practical value of the whole
    project. The present unavailability of manufactured and successfully
    tested toroidal coils prevents assembly of vacuum vessel, cryostat,
    and thus the further development of the project. The situation is
    complicated by the fact that manufacturing superconducting coils
    unfortunately has a useful output considerably less than 100%. In
    practice the coils should be manufactured and tested one after
    another, as the real number of manufactured units may be much higher
    than 16. In terms of the project development, the above implies that
    essential delays should be expected.

2.  The second priority for this project is the in-vessel equipment,
    such as control and divertor coils, and plasma facing elements, such
    as limiters and divertor plates. These components are extremely
    complex and challenging, and are critical to plasma performance
    during future tokamak operations, and can influence the success of
    the whole project. The development, design, and testing of this
    in-vessel equipment should be subject to a high level of attention.
    However, at present the manufacturing of these components has not
    been started, while some parts, such as the FEC / RWM coils, are not
    even designed yet. An increase in efforts to develop these
    components is recommended. As well, due to the extreme importance of
    these components, it would be helpful to develop several different
    versions, using different configurations and materials.

3.  The subject that is of next highest priority is the specification of
    the minimum objectives of the first plasma experiment, and the
    selection of the required diagnostics set. The first plasma
    experiment is the critical first step of the research program. Among
    the aims of the first plasma experiment are:

```{=html}
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```
(1) To establish adequate vacuum conditions, magnetic field null and
    loop voltage to obtain a plasma with minimal parameters, such as Ip
    \~ 500kA, \<n\> \~10^12^ - 10^13^ cm^-3^ and T~e~\> 200-300 eV

(2) To provide credible measurements of these parameters.

(3) 

(4) To provide radial and vertical position control of the plasma using
    closed loop feedback control techniques.

(5) To obtain experience in wall cleaning and conditioning procedures
    and investigate their effects on plasma parameters.

> To realize these objectives, a minimal but reliable diagnostic setmust
> be available for first plasma.

B. Unfortunately due to budget constraints, the plasma diagnostics
preparation has not yet gotten underway. It should be noted that Thomson
scattering is the most reliable technique for measuring the temperature
of plasma, and is used on practically all tokamaks operated throughout
the world. This diagnostic will also be needed in the KSTAR first
campaign (CALVIN: I'M NOT SURE THAT THIS IS REALLY TRUE???? FIRST PLASMA
IS USUALLY A QUICK FLASH IN THE PAN). Unfortunately, the development of
this diagnostic is very complicated and it usually requires two to three
years of preliminary laboratory study. A special laboratory test
facility using an identical sector of vacuum vessel would be helpful for
this study. It requires intensive and immediate efforts in development
and manufacture of these diagnostics for Thomson scattering to be
available in the first plasma campaign. The other basic diagnostic
system necessary for first-plasma experiments is a microwave
interferometer, which can provide reliable measurements of plasma
density and its time evolution. It makes sense to start with simple 1 to
2 mm equipment, keeping the advanced FIR technique for the next
experimental campaigns.

C. Radiation shielding and radiation protection program

> As soon as the NBI facilities are implemented in the KSTAR project,
> induced radiation will emerge as a new feature of tokamak operation.
> No access into the test cell will be possible for 5 -- 10 hours after
> NBI-heated plasma operation, and work on many components of diagnostic
> equipment will be restricted. This situation will require that
> radiation shielding be built close to the tokamak facility and
> NB-injectors. Qualified special personnel and appropriate equipment
> will be needed to provide a radiation safety program. This issue seems
> to have been neglected in the existing project. (CALVIN: I'M NOT SURE
> THAT THIS IS REALLY TRUE, SINCE KSTAR WILL NOT USE TRITIUM, AS FAR AS
> I KNOW.. THERE WILL BE SOME ACTIVATION WITH NBI DRIVEN D-D BUT MY
> RECOLLECTION BASED ON TFTR EXPERIENCE WITH 30MW NBI IS THAT IT WILL
> NOT BE A MAJOR ISSUE. ON NSTX IT IS NOT AN ISSUE WITH 8MW OF NBI)

D.  The vacuum vessel of KSTAR and therefore the cryostat is designed to
    have 120 diagnostic and technologic ports. Such a large quantity of
    ports increases the hot area in the cryostat from 40 square meters
    (vacuum vessel itself) to 120 square meters, thus considerably
    increasing the inward heat flux and therefore the consumption of
    liquid helium. There is a certain risk that the cooling down of the
    superconducting magnet will not be achieved in this cryostat. There
    is also a risk that the capacity of the liquid helium production
    facility is not sufficient to feed KSTAR. Additional detailed and
    expert study of the cryostat is strongly recommended prior to the
    start of assembly of the facility.

E.  An electric power supply system that is able to provide the KSTAR
    facility with a peak power of over 100 MW is necessary. This system
    must eventually utilize an energy-storage device (a motor-generator)
    to cover power peaks that occur during NBI, ECRH, and ICRH
    operations. While an MG system has been envisioned and planned, it
    is a very long lead item. This factor needs to be taken into account
    in the planning of the research program after first plasma and
    initial operating campaign.

**COMMENTS ON THE SCHEDULE**

There are several concerns related to the allotted schedule of the
project between the completion of component manufacturing and the first
plasma experiments. The first concern relates to cool-down and leak
checking. First plasma will require the full assembly of the machine,
and testing and conditioning of the vacuum-vessel for plasma operation.
The leak tests of the vacuum vessel and the cryostat are some of the
most difficult and time-consuming procedures involved in this project.
As soon as all leaks are sealed, a preliminary cool-down test must be
performed. More likely than not, this cool-down will cause new leaks
which will require repair, and additional leak testing. At present these
two steps, preliminary cool-down test and post-cool-down leak tests, are
not accounted for in the schedule of the KSTAR project. The second
concern relates to the KSTAR assembly process. Due to the high
complexity of the facility, it is reasonable to expect errors and
incompatibility in some portion of the components. This has certainly
been the experience of many other tokamakconstruction projects.
Therefore, additional time will be needed for rebuilding, modifying, and
replacing of non-conforming parts, which is not factored into the
present project schedule. The third concern relates to the time interval
between the completion of assembly and start of first plasma
experiments. The aims of this step are to reach high vacuum and to
condition the walls of the vacuum vessel, using several technologies
such as glow discharge, RF--dischargeplasma discharge, etc. The success
of these procedures provides the basis for satisfactory plasma
performance during the tokamak's initial operation. The first tokamak
operation after initial assembly may require more preparation in terms
of pumping and conditioning than allowed by the present schedule. For
these reasons the time interval between the completion of assembly and
start of first plasma experiments could extend beyond the 6 months
allocated by the current schedule.

# **[E. RECOMMENDATIONS]{.underline}**

# 

# 

# **Design**

The basic design of KSTAR and the major KSTAR subsystems considered in
this review process appear to be fundamentally sound. Most major
subsystems have passed successfully from the conceptual design stage,
through engineering design and review, to the prototype stage, and are
now ready for production.

# **R&D**

To date, most R&D tasks have focused on verification of concepts and on
demonstration of readiness to proceed to detailed engineering design and
production. To this end, the program has been generally successful. At
present, further R&D activity may be justified to support the reduction
of risk and cost in certain areas.

# **Production/Assembly**

As the various subsystems move into production, significantly tighter
integration of all tasks becomes essential. During production,
uniformity and control of materials, processes, and nterfaces with other
subsystems becomes even more important thanimproved performance, since
even small changes made for seemingly good reasons on one subsystem can
have a drastic impact on the performance of other subsystems or of the
whole. Close coordination of production schedules also ensures an
efficient assembly of the overall system.

# **QA/QC**

The test programs carried out as part of the R&D activities for the
various subsystems provide a firm basis for a successful QA/QC program
but they do not substitute for it. The KSTAR project is presently at the
stage where it must make the transition from testing to production to
and ensure success by minimizing risk and unexpected costs, i.e. by
implementing the necessary procedures and process controls, and QA/QC
measures in each task area.

# **Safety**

A system as complex as KSTAR and that includes as many state-of-the-art
subsystems, presents a variety of hazards -- to personnel, to equipment,
and to facilities. At present, these safety issues appear to be left to
the managers of the separate subsystem tasks, which may give rise to
inconsistent coverage or even conflict. It seems prudent to consolidate
the responsibility for so important an issue under a single authority.
As the project approaches the commissioning and first plasma phase, a
review of readiness for operations would seem necessary and appropriate.

# **Project Management**

The project should hire a project management team. The science team is a
very strong one, but project managers with large scale engineering
project management experience are required to assure the success of the
project. All of the subcontracts through Korean industrial construction
companies have been professionally executed, and have delivered quickly
with high quality. The same type of experienced industrial project
management needs to be applied to the KSTAR project.

## Contingency Planning

KSTAR is a very complex system, and planning for future uncertainties is
essential to the success of the project. The KSTAR team leaders have
recognized this and are working toward effective contingency planning.

**Milestones**

We recommend that KSTAR consider attainment of first plasma as the next
major milestone.

[^1]: There are at least three criteria for specifying the tolerable
    leak rate:

    Threshold for spoiling vacuum during operation of the magnet system

    Threshold for compromising insulation during VPI (pressure on inside
    greater than minimum pressure during VPI causing bubbles in the
    resin)

    Threshold for drawing appreciable quantity of resin into CICC during
    VPI (pressure on inside of CICC less than maximum pressure during
    VPI allowing resin to be drawn into the cable space and blocking
    flow).

    The latter two are dependent on details of the process (relative
    pressure between inside and outside the conduit during
    impregnation). In any case, a clear specification of the criteria
    and the resulting tolerable leak rate is important. When and how
    often leak test is done may also depend on the criteria. Certainly
    the completed magnet should be leak tested prior to installation
    with an allowable value based on potential for spoiling the cryostat
    vacuum, but it is also prudent to test prior to specific
    manufacturing stages where considerable value will be added, e.g.
    winding, heat treatment, and VPI. It is conceivable that the
    allowable value could be different at each stage based on a careful
    evaluation of the relative risk vs cost of the test.