# Presentation: 111089

## RHIC SYSTEMSPower Supplies ,Superconducting Magnets, Quench Protection , etc.G. Ganetis6/08/04

## Outline

**Work Done Before and During Run 4**
**Power Supply and other Systems Performance for Run 4**
**Work Planed for Summer 04 and During Run 5**

## Work Done Before and During Run 4Power Supplies

**Corrector Power Supplies**
- All 620 removed and modified
- Trips to OFF state fixed
- Parking Circuit added to p.s.
- DC Over Current circuit adjusted
- Tightened all AC connections
- Tightened all DC connections at CQS magnet trees
- Increased 208 VAC substation voltages
- Found problem with Error trips on corrector p.s.’s
- Major review of corrector p.s. schematics to determine FINAL changes to corrector p.s.’s

## Work Done Before and During Run 4Power Supplies

**IR power supplies**
- All 150A and 300A bipolar units removed
- Replaced shorted soft start IGBT’s
- Install Relay board fix for soft start
- Add MOV’s to ac inputs
- Insulated screw which caused hi-pot problems
**Sextupole P.S.’s**
- Added buffer for current readback signal to quench detector

## Work Done Before and During Run 4Power Supplies

**Main Power Supplies**
-  New DSP code
- Regulation Error Signal interlock added
- New PLC code
- Reconfigured Soft Grounds.
- Improved mounting of Quench Protection DC Contactor snubber capacitors
- Changed DCCT connector in the Yellow Dipole.

## Work Done Before and During Run 4 Power Supply Software Modifications

- 720Hz data added to snapshot
- Last command saved added to PLC software
- Timing resolver software improved
- Changes made to WFG manger to prevent system trips due to wrong ramp rates when off the hysteresis curve.

## Work Done Before and During Run 4SC Magnets

**Y3 Q7  Voltage Tap –**** **
-    The ceramic feed through had significant carbon tracts on it.  It caused multiple trips of the system due to excessive ground current.  We were able to nurse it during the rest of the run after it was identified.  Cause of the problem was probably due to excessive moisture at the feed through. A new ceramic feed through was installed .

## Work Done Before and During Run 4SC Magnets

**HRD102  Snake ( yellow sector 9 ) – ** Superconductor is open in # 2 (B) magnet, which is HSD 205.. An autopsy of the magnet was done , but the results were not conclusive as to the cause of the failure. This snake magnet was removed from the tunnel and was repaired and the re-installed.
**HRD101 Snake ( blue sector 9 ) - **New ceramic insulators were installed on the magnet in the tunnel. The gas cooled leads were made longer to decrease the heat leak.
**HRD 302 Spin Rotator ( blue sector 6 ) - **HSD 409 ( A ) had a low resistance short to ground at the bottom of the A + lead. The lead was disassembled and the short repaired in the tunnel.

## Work Done Before and During Run 4SC Magnets

- Y7TQ6 developed a high resistance between run 3 and run 4. This is not a problem at the present current levels.

## Work Done Before and During Run 4Quench Protection

**Quench Detector Hardware – **In testing the failed Rhic helical magnet in bldg. 902. A problem was found in the way the magnet voltages were being monitored for a quench. Instead of total coils being monitored we now have to monitor half coils. This required the addition of new hardware. This information was not found out until very late in the run , but we were able to install all the new hardware before the proton run.
**Quench Detection Server-  **A new NT server was installed
**Quench Detection Software- **New software was installed that improves the time stamps of quench alarms. The latest version of software was installed late in the run and seems to be working. Also changes were made to the DSP code to decrease the detection time in helical magnet quenches.

## Work Done Before and During Run 4Quench Protection

**Quench Detection Tuning-**
-      New inductance tables were developed that allows faster ramps from park to injection, top energy to injection, and injection to park.

## Work Done Before and During Run 4"Ice Balls“

- Installed foam insulation on the base of every CQS lead and on all gas lines.
- Replaced thermostats on all leads with new ones that will maintain a higher temperature. (from 32-48  ̊F to 70-86  ̊F)
- Installed new 1-wire temperature monitoring system for all voltage tap feed through flanges in the tunnel and on high current leads in the valve boxes. This data was logged by the control system.
- Adjusted lead flows back to their nominal levels.
- Installed 1-wire temperature monitoring on gas cooled leads on the valve boxes.
- No down time due to “ice balls” this run.

## Power Supply and other Systems Performance for Run 4 60 correctors swapped out last run25 correctors swapped out this run

## Power Supply and other Systems Performance for Run 4IR Power Supplies

- 2 – bipolar 150A’s and were swapped out this run vs 14 last run
- 1 – bipolar 300A was swapped out this run vs 6 last run
- 19 aux contacts replaced on unipolar IR p.s’s. this run vs 10 last run (problem was never fixed last shutdown so it continued this run)

## Power Supply and other Systems Performance for Run 4QLI Counters

## Power Supply and other Systems Performance for Run 4Helical Magnet System Trip Counters

## Power Supply and other Systems Performance for Run 4Run to Run Comparison

**Power Supply and other Systems Performance for Run 4****Run to Run Comparison**

## Power Supply and other Systems Performance for Run 4Run to Run Comparison

## Power Supply and other Systems Performance for Run 4Run to Run Comparison

## Work Planed for Summer 04 and During Run 5

- IR and Corrector Power Supplies
- Unipolar IR p.s.’s aux contacts error fault being fixed.
- Installing MOV’s in rack mounted unipolar p.s.’s
- Fixing Error Trips for corrector p.s.’s
- Modifying Slew Rate Limiter for corrector p.s.’s ( From 1kHz to 5 Hz )
- Test writing to node card ports individually
- Main Power Supplies
- Adding instrumentation to monitor current in the OCC Quench Protection Main SCRs.
- Adding instrumentation to monitor gating of OCC Quench SCRs.
- Maintenance on all Phoenix style connector connections.

## Work Planed for Summer 04 and During Run 5

**	****Quench Detector Hardware - ** Replace temporary connection to the helical magnet voltage taps with the permanent design.
**	****Quench Detection Software –**** **Continue** **testing new software over summer shut down.
- 	**Quench Detection Tuning – **Improve inductance tables to allow even faster ramps from park to injection, top energy to injection, and injection to park. This will be done during the start-up of the machine.
- 	**Quench Protection Switches – **Perform maintenance on all 6 KAmp mechanical interrupter and tighten all connection.

## Work Planed for Summer 04 and During Run 5

- 	**“ ****ICE BALL” Prevention**
- Modify heaters and thermostats that are on the triplet corrector leads.
- Modify heaters, replace thermostats, install insulation and re-position 1-wire temperature sensors for the valve box 12 by 150 amp gas cooled leads.
- Install heaters and thermostats and re-position 1-wire temperature sensors on the valve box 1600 and 6300 amp gas cooled leads .

## Work Planed for Summer 04 and During Run 5

**Corrector Lead Voltage Monitor System**
- Install new 1-Wire voltage monitor boards at each CQS and triplet corrector lead.
- There will be 492 boards.
- Each board can monitor 4 signals.
- The system monitors the total voltage across a magnet circuit right at the room temp. end of the gas cooled leads.
- When the magnet current is DC ( Not ramping ) the voltage measured is then the lead voltage.
- This system will allow for the first time a way to measure the performance of these gas cooled leads. This can lead to operational flexibility when there is a low flow condition.
- The final goal for this system is to develop a corrector lead interlock system that is independent of the cryo lead flow .

## Work Planed for Summer 04 and During Run 5

**New Software and Software Modifications**
- Temperatures from the “Ice Ball “ monitor are to be put in the modified Alarm system. ( Temperature has to be below or above alarm levels for a fixed length of time to cause an alarm. )
- Need more data from the cryo system to be available remotely and for it to be logged.   (  lead flows and temperatures )
- UPS monitoring  that will have alarms and give correct direction to operations when AC power is lost on critical systems.
- Voltage monitor for corrector leads.
- Improvement to Quench Recovery in TAPE
- Is there interest in modifying the QED application so that will be able to duplicate the Quench Link Trip analysis that I put into the E-log ? This analysis would be available 5 min. after each link trip.