TPS CORRECTOR MAGNET POWER CONVERTER
Based on the requirement of beam stability for the third-generation synchrotron radiation light source is more stringent, lower ripple and higher bandwidth of output current of corrector magnet power converters should be developed to implement the closed orbit correction of Taiwan Photo Source (TPS). The ±10A/±50V corrector magnet power converter uses a full bridge configuration, the switching frequency of power MOSFET is 40 kHz, in that each bridge leg has its own independent PWM controller and the output current bandwidth is 1.5 kHz when connected with the corrector magnet load. Using a DCCT as the current feedback component the output current ripple of this converter could be lower than 5 ppm. In this paper, we will describe the hardware structure and control method of the corrector magnet power converter and the test results will be demonstrated.

title: Search for VHE Gamma Ray Emission from SNRs with the Data of Tibet ASg III
abstract: The paper discusses some preliminary results about gamma ray emission from some of SNRs by analysing the data of Tibet ASγ III. The equi-zenith angle method and Right Ascension scan with livetime correction are used. The significance derived from t test for the results is discussed.

title: TPS Magnet Power Supply System
abstract: The Taiwan Photon Source (TPS), a third-generation synchrotron radiation light source, should be installed with 1032 sets of magnet power supplies for the storage ring and 152 sets for the injector. All of the power supplies are preferred in PWM switched mode with IGBT or MOSFET. A high precision DC power supply for 48 dipoles of the storage ring; there are 240 quadrupole magnets and 168 sextupole magnets in storage ring, the main winding of quadrupole and sextupole magnets are powered by individual power supplies. In the booster ring, one set of dynamic power supply for the dipole magnets and four sets for quadrupole magnets run at the biased 3Hz quasi sinusoidal wave. There are several hundred corrector (fast and slow) magnets and skew quadrupole magnets in storage ring and injector are powered by the same bipolar power converters.  There are more than thousand of power supply will be installed at TPS, based on the different requirements of power supplies for different magnets and budgetary concern, all power supplies are divided into three categories. These three categories include two outside procurements and a cooperative project. Outside procurements: AC and large magnet power supplies A storage ring dipole magnet power supply A booster ring dipole magnet power supply Four booster ring quadrupole magnet power supplies Medium power supplies 240 units of storage ring quadrupole magnet power supplies 168 units of storage ring sextupole magnet power supplies LTB dipole& quadrupole、BTS dipole& quadrupole and DC septum power supplies A cooperative project with CMS, ITRI Corrector magnet power converters Booster ring horizontal & vertical corrector Trim coil of storage ring sextupole magnet(include horizontal dipole 、 vertical dipole & skew quadrupole) Fast feedback corrector AC AND LARGE MAGNET POWER SUPPLIES TPS is required to operate 24 hours per day, 7 days per week, for several successive weeks. Consideration of minimizing repair and recover time, the large and AC power supplies must be designed to maximize the use of plug-in modules, especially for regulation circuitry and power stage. These power supplies shall be switched mode with digital current and voltage regulation loop. The following features should be designed into a modular architecture: A high degree of modularity is desired. An N+1 redundant architecture for power stage. An N+1 redundant architecture for chopper regulator module. Identification of failed modules should be accessed by the remote control system. ‘Hot Swap’ replacement of failed modules. Storage ring dipole power supply A single power supply will be adopted to power 48 dipole magnets connected in series, and the main specification of magnet and power supply are as follows: Table 1: Storage Ring Dipole Magnet Magnet designation Dipole No. of magnets 48 Peak current 640A Inductance 31mH Resistance 20.82 mΩ Table 2: Specification of Storage Ring Dipole Power Supply Output(A/V) 750A/850V Short term stability(0~30min) ±5ppm /± 3.75mA Long term stability(0~8hrs) ±10ppm /± 7.5mA Resolution 18bits Accuracy ±50ppm Booster ring dipole power supply The operating repetition rate of booster ring is 3Hz, and the power supplies will output a biased sinewave to power booster magnets to generate a field profile from injection to peak field over the beam energy range 130MeV-3.0GeV. There are two different kinds of dipole magnet, their parameters are listed in table 3.  Booster Ring Dipole Magnet Magnet designation BD BH No. of magnets 42 12 Peak current 1034 1034 Inductance 1.8mH 0.9mH Resistance 8.1mΩ 5.1mΩ A single power supply(table 4) will be adopted to power 54 dipole magnets connected in series. The current reference function generation shall include: Proceedings of IPAC’10, Kyoto, Japan WEPD075 07 Accelerator Technology T11 Power Supplies 3275 Direct current setting command An arbitrary waveform: Store the waveform with programmable current setting points (maximum is 65,000). After cycling the arbitrary waveform, the output current setting of power supply shall be keep at bottom value of the arbitrary waveform. Direct current setting command + arbitrary waveform Table 4: Specification of Booster Ring Dipole Power Supply Output(ampere/voltage) 1200A/±1300V Short term stability ±5ppm /± 6mA Long term stability ±10ppm /± 12mA Resolution 18bits Accuracy ±50ppm Booster ring quadrupole power supplies There are two different kinds of quadrupole magnets, and these magnets are grouped into four families, table 5 is the list of these quadrupole magnets.  Booster Ring Quadrupole Magnets Magnet designation QF Q1/Q2/QM No. of magnets 48 12/12/12 Peak current 82A 104/66/31A Inductance 2.03mH 2.03mH Resistance 47mΩ 47mΩ Although there is a large difference on inductance and resistance between QF(48 magnets in series) and Q1/Q2/QM(12 magnets in series), but concerning about maintenance, power supplies with the same specification will be adopted to power these four families of quadrupole magnets, the specification is listed in table 6. Table 6: Specification of Booster Ring Quadrupole Power Supply Output(A/V) 120A/±425V Short term stability ±5ppm /± 0.6mA Long term stability ±10ppm /± 1.2mA Resolution 18bits Accuracy ±50ppm MEDIUM POWER SUPPLIES There are 240 quadrupole magnets and 168 sextupole magnets in TPS storage ring, and all these magnets are powered by individual power supply. The power supply with the same 250A/30V power rating to power all quadrupole and sextupole magnets, but quadrupole magnets shall be powered by more stable power supplies than that for storage ring sextupole magnets, so there are two different specification on the performance of output current but with the same control function. Table 7 list the main parameters of quadrupole and sextupole magnet, table 8 is the main parameters of specification of quadrupole and sextupole magnet power supplies. Table 7: Storage Ring Quadrupole And Sextupole Magnets Magnet Quadrupole Sextupole No. of magnets 240 168 Peak current 188A 135A Inductance 13.6/23.5mH 5.8mH Resistance 72.2/81.6mΩ 43.8mΩ Table 8: Specification of Quadrupole & Sextupole Magnet Power Supplies quadrupole sextupole Output(A/V) 250A/30V 250A/30V Short term stability ±1.25 mA ±6.25 mA Long term stability ±2.5mA ±12.5 mA Resolution 18bits 16Bits Accuracy ±10mA ±50 mA These power supplies will be embedded with some special functions: Waveform data Up to 64 k samples Post-mortem buffer shall be built inside, and this buffer must record data of output current. Sampling rate must be adjustable and maximum sampling rate is 10 ks/sec. External trigger (pre-post trigger mode). Series and parallel operation with Master/Slave control function. With post-mortem function, if there is a beam trip or any fault of power supply it will be much easier to identify which power supply is the causality. With series and parallel operation, there are some magnets could be powered with sextupole power supplies such that don’t need several different rating power supplies and types of power supply could be minimized that could save lots of maintenance. The magnets could be powered with sextupole power supplies are presented in Table 9. Table 9: Magnets Powered by Sextupole Power Supplies Magnet Quantity of power supply LTB dipole 2 LTB qudrupole 1 DC Septum 3 BTS dipole 3 BTS qudrupole 1 The bid of medium power supplies was held at 16, APRIL, and CHROMA ATE INC., Taiwan won the bid. There is a standard power supply product 62075H-30[1] of CHROMA suitable to use as the sextupole magnet power supply and just need a little bit of modification. The performance of CHROMA 62075H-30 power supply is demonstrated in figure 1. WEPD075 Proceedings of IPAC’10, Kyoto, Japan 3276 07 Accelerator Technology

title: THE COMPENSATOR DESIGN OF THE FULLY DIGITAL CONTROLLED CORRECTOR MAGNET POWER CONVERTER BY USING LABVIEW AS THE DEVELOPMENT TOOLS
abstract: The auto-tuning of PI-compensator for the digital regulation controlled corrector magnet power converter is fulfilled by using the LabVIEW. The current error signals of the power converter with different PI compensating parameters are transferred by RS-232 or Ethernet communication interface from DSP card into LabVIEW and FFT analysis are calculated. The FFT analysis are stored in the batch file for further numerical analysis, the parameters with the best response will be recognized and set as the default PI parameters. In addition, the feasibility and validity of auto-tuning theorem was verified by measuring the long-term stability of output current, and during the long-term measuring period the stability and ripple current of the power converter are also observed. In this paper, the fully digital regulation controlled corrector magnet power converter with a shunt as the current sensing component was used as the developing platform. The PI parameters auto-tuning method was realized and applied to the compensator of the power converter, and the best output current response of the power converter was fulfilled.

title: N + 1 REDUNDANCY POWER SUPPLY SYSTEM BY PARALLELING CURRENT CONVERTER MODULES WITH DIGITAL REGULATION CONTROL
abstract: The N+1 redundancy power supply system is fulfilled with adopting the Bira System MCOR30s as a platform, eight pieces of Bira MCOR 30 power converter boards are installed at crate 2512 and outputs are connected together, the output current of these paralleled eight Bira MCOR 30 power converters are regulated by an external homemade digital control circuit. With homemade digital control circuit, these paralleled eight Bira MCOR 30 power converter modules could deliver up to 240A/30V with ±20ppm precision and stability. The digital regulation control circuit of the N+1 redundancy power supply system is implemented by using a multi-channel DAC5868 16-bits digital-to-analog converter (DAC), a high speed AD8382 18-bits analog-to-digital converter and a TMS320F28335 digital signal processor (DSP). The update reference voltage frequency of DAC is 83.3 kHz. A DCCT is used as the current feedback component and the output current ripple of the N+1 redundancy power supply system is lower than 20ppm which is beyond the requirement of current TLS quadruple and sextuple power supplies and qualified to be used in the future TPS facility.[1~2] INTRODUCTION In the storage ring of TLS, the Bria MCOR 30 power modules are used as the corrector magnet power converters, the regulation of the MCOR 30 power module is convectional analog control, the amount of the MCOR 30 power modules have 123 piece. For the new TPS project, the digital control quadruple and sextuple magnet power converters are considered to be adopted and installed for future operation in 2014. Therefore, the power supply group of NSRRC is now studying and developing a N+1 redundancy power paralleling current converter modules in which digital regulation control is implemented and the voltage reference can be changed on the fly according to different paralleling current amount of Bira MCOR 30 power modules. To confirm the accuracy of digital regulation control policy before implementation of the circuitry, this N+1 redundancy power paralleling current converter modules is simulated with MATLAB simulink, the behavior of Bira MCOR30 configuration, power paralleling current converter structure and the P-I compensator are included. There are four main components are embedded in the digital regulation control circuit, Texas Instrument TMS320F28335 DSP controller, multi-channel DAC5868 16-bits DAC converter, high speed ADS8382 18-bits ADS and LEM IT 600-S Ultrastab DCCT, and the performance is verified by using the MCOR30 power module and Bira Crate 2512 as the platform. With this digital regulation control circuit, output current control reference signal voltage is connected to everyone MCOR30 converter board and the output current ripple is well controlled below ±20ppm that meets the specification of quadruple and sextuple magnet power converter. THE STRUCTURE OF N+1 REDUNDANCY POWER SUPPLY The N+1 redundancy power supply could be roughly divided into five functional blocks: Bira MCOR 30 power modules and Bira MCOR crate 2512/ high speed AD8382 18-bits analog-to-digital converter/ multi-channel DAC5868 16-bits digital-to-analog converter/ DSP TMS320F28335 controller and USB/JTAG transmission interface. Figure 1 shows the structure of N+1redundancy power supply circuit, Figure 2 is the Bira MCOR 30 power converter module boards and MCOR Crate2512.  The structure of N+1 redundancy power converter.  The Bira MCOR30 power converter board and Bira MCOR Crate2512. DC BUS +48Volt DC Power Supply MCOR 30 Crate