# Presentation: 149954

## Proton Driver Magnet Power Supply System

**Cezary Jach  **
**BD/EE Support**
- April 19, 2000

## System Top Level Parameters

**Frequency - 15 Hz**
**Dipole peak stored energy - 9.1 MJ (Main Injector dipole 14.7 MJ @ 120 GeV)**
**Dipole peak field - 1.52 T**
** ****B****max****/B****min**** = 17.7**
**Quad.  peak stored energy - 2.1 MJ**
**Quadrupole peak gradient - 8.9 T/m**
**G****max****/G****min**** = 17.7**

- Cezary Jach - BD/EE Support

- April 19, 2000

## Design Choices

**SCR power supply system (similar to Main Injector)**
**Dipole power supply system S = 550 MVA peak**
**Quadrupole power supply system S = 50 MVA peak**
**Combined S = 600 MVA peak (Main Ring 300 MVA peak @ 500 GeV), mostly reactive power**
**approximately 4 times existing site peak power **
**returns reactive power to the grid with 15 Hz frequency**
**difficult & costly reactive power compensation**
**IGBT power supply system (S. Fang)**
**Resonant power supply system (similar to Booster)**

- Cezary Jach - BD/EE Support

- April 19, 2000

## Resonant Power Supply Systems

**Single frequency. Current is in the form of biased sinusoid**** **
**Dual frequency. Current is in the form of 15 Hz biased sinusoid with superimposed 30 Hz component- chosen design**
**Switched. Current is in the form of biased 10 Hz sinusoid when rising, and 30 Hz when falling**

- Cezary Jach - BD/EE Support

- April 19, 2000

## Switched System Magnet Current

**Ripple at injection = 270 ppm p-p **

- Cezary Jach - BD/EE Support

- April 19, 2000

## Dual Frequency Resonant Power Supply System

**LCR network with single resonant frequency at 15 Hz, driven by a source containing 15 Hz and 30 Hz frequencies (30 Hz needs 15 MVA peak)**
**LCR network with two resonant frequencies at 15 Hz and 30 Hz , driven by a source containing 15 Hz and 30 Hz frequencies - chosen design**

- Cezary Jach - BD/EE Support

- April 19, 2000

## Adding 2nd Harmonic to Magnet Current

- Cezary Jach - BD/EE Support

- April 19, 2000

## Resonant Power Supply Systems

- Cezary Jach - BD/EE Support

- April 19, 2000

## Power Supply System Parameters

**System design based on lattice version 1, dated Jan. 1, 2000**
**Total induced voltage = 167 kV, number of res. cells = 27 **
**System Voltage**
**Voltage across cell, peak = 6,200 V (Booster 940 V)**
**Voltage to ground, peak = 3,100 V (Booster 470 V)**
**Magnet Current**
**Peak Current = 7,500 A**
**Minimum Current = 420 A**
**DC Current = 3,700 A**
**AC Current, fundamental, peak = 3,500 A**
**AC Current, 2nd harmonic = 440 A**

- Cezary Jach - BD/EE Support

- April 19, 2000

## Proton Driver Magnet Power Supply Diagram

- Cezary Jach - BD/EE Support

- April 19, 2000

## Resonant Cell Elements

- Cezary Jach - BD/EE Support

- April 19, 2000

## Resonant Cell Frequency Response

- Cezary Jach - BD/EE Support

- April 19, 2000

## Power Supply System

**3.6 MVA of DC power - special cell for DC power supply insertion. Power supply rating - 4.5 MVA**
**14.5 MVA peak at 15 Hz, either “injected” through secondary windings of dc bypass choke or in series with magnets. Power supply rating - 27.0 MVA**
**0.8 MVA peak at 30 Hz, either “injected” or in series with magnets. Power supply rating - 1.5 MVA**
**27 chokes, 100 t, 425 kJ, 3m  x 4m  x 4m**

- Cezary Jach - BD/EE Support

- April 19, 2000

## Power Supply System Parameters

- Cezary Jach - BD/EE Support

- April 19, 2000

## Quadrupole Tracking Error Tolerance Study

- ISIS experience,   0.01

- To avoid space charge tune spread edge to touch a 4th order resonant line (space charge = 0.06)

- Cezary Jach - BD/EE Support

- April 19, 2000

## Quadrupole Tracking Power Supply Choices

**Independent power supply circuits**
**Quadrupole main coils in series with dipoles**
**bucking chokes to produce opposing induced voltage**
**quadrupole trim coils connected in series with secondary of bucking choke**
**IGBT power supplies (Main Injector sextupole power supply style), will meet required current, voltage and bandwidth**

- Cezary Jach - BD/EE Support

- April 19, 2000

## Quadrupole Tracking System Diagram - 1/3 of the Ring

- Cezary Jach - BD/EE Support

- April 19, 2000

## Quadrupole Tracking

- Cezary Jach - BD/EE Support

- April 19, 2000

## Quadrupole Compensation

- Cezary Jach - BD/EE Support

- April 19, 2000

## Quadrupole Tracking

**|********|****max**** ******** 0.01% if compensation current includes up to 7th harmonic**

- Cezary Jach - BD/EE Support

- April 19, 2000

## Quadrupole Tracking and Tune Control

**Power supply peak current rating at given frequency is set by required tune compensation or tracking, whichever is higher**

- Cezary Jach - BD/EE Support

- April 19, 2000

## Quadrupole Tracking Calculations

**Assume bucking choke’s main inductance**
**Calculate trim circuit input impedance at each frequency**
**Assume calculated previously required peak currents for each frequency**
**Calculate required peak voltages for each frequency**
**Vary quad turns ratio to arrive at reasonable power supply current/voltage ratings**
**Calculate bucking choke turns ratio**

- Cezary Jach - BD/EE Support

- April 19, 2000

## Quadruple Tracking Circuit Calculation Results

**Bucking choke  requirements:**
**L1 = 2 mH, L2 = 4.31 mH, k = 0.98**
**N1 = 32, N2 = 47,  ******** = 0.03%**
**74 kJ**
**Quadrupole turns ratio 4:1**
**Power supply requirements:**
**210 Hz minimum bandwidth**
**860 A peak, 608 V peak**
**6 power supplies, 608 kVA peak each**
**Capable of 4 quadrant operation**

- Cezary Jach - BD/EE Support

- April 19, 2000

## Conclusions

**Well proven technology**
**Very large components**
**More detailed design and complete system simulations will be done after lattice design is stabilized. **
**Challenges**
**3,100 V magnets**
**Quadrupole tracking**
**Regulation (DC, 15 Hz, 30 Hz)**

- Cezary Jach - BD/EE Support

- April 19, 2000