Author: Liu, K.-B.
Paper Title Page
THPO012 Using a High Precision Programmable DC Power Supply of TPS Magnet 3358
  • Y.S. Wong, J.C. Huang, K.-B. Liu, W.S. Wen
    NSRRC, Hsinchu, Taiwan
  Taiwan government had been announcement to set up a third-generation synchrotron radiation light source in February 2010. It should be installed with 1032 sets of magnet power supplies for the storage ring and 152 sets for the injector. In the storage ring, high precision DC power supply for 48 dipoles magnets , 240 quadrupole magnets and 168 sextupole magnets. The main windings of quadrupole and sextupole magnets are powered by individual power supplies. In the booster rings, one set of dynamic power supply for the dipole magnets and four sets for quadrupole magnets run at the biased 3Hz quasi sinusoidal wave. The Taiwan photon source (TPS) plan was completed indication national synchrotron radiation research central (NSRRC) technical capability to build at its present site in seven years a 3~3.3 GeV electron energy, 518 meter circumference, low-emittance synchrotron storage ring which will offer one of the world's brightest synchrotron x-ray sources, provide cutting-edge experimental facilities and novel multidisciplinary scientific research opportunities, enhance world-class academic research, as well as create Taiwan's scientific research marvels in the twenty-first century.  
THPO013 Development of a DSP-based Digital Control Three Phase Shunt Active Power Filter for Magnet Power Supply System 3361
  • B.S. Wang, K.-B. Liu, Y.S. Wong
    NSRRC, Hsinchu, Taiwan
  There will be 240 quadruple and 168 sextuple magnet power supplies installed in TPS storage ring, power factor of these power supplies is an important issue to be concerned. A digital control three-phase shunt active power filter (APF) for quadruple and sextuple magnet power supplies is implemented and the power factor is better than 0.98. The APF power stage employs a three-phase switch-mode rectifier (SMR) to reduce the input current harmonics distortion and correct the power factor. The digital control circuit of the three-phase shunt active power filter is implemented by using a multi-channel 12 bits analog-to-digital converter、high resolution Pulse Width Modulated (PWM) and a TMS320F28335 digital signal processor (DSP). The system configuration is described in three function blocks include principle of compensation、design of the snubber protective circuit and control strategies. Finally, the feasibility and validity of proposed scheme is simulated with Matlab simulink and verified by the homemade digital control three-phase shunt active power filter.  
THPO014 Analysis and Compensator Design of Magnet Correction Power Supply 3364
  • Y.S. Wong, J.C. Huang, K.-B. Liu
    NSRRC, Hsinchu, Taiwan
  This paper presents a new method for the analysis and design of compensators for magnet correction (MC) power supply. The system has to need controllers to satisfy required gain and phase margin specifications and compensator by adding to circuit controller and switch. The gain-phase margin tester method can transform of the controller and find solutions on the figure. According to circuit frequency response and transfer function by theory analysis and simulation design new method compensators to improved anti-disturbance and stability of the system.  
THPO015 External Energy Dump for Superconducting Magnet of the Uni-polar Power System 3367
  • Y.S. Wong, K.-B. Liu, W.S. Wen
    NSRRC, Hsinchu, Taiwan
  This thesis focuses on the design of superconducting discharge energy circuit structure in Uni-polar power supply [1]~[3]. Superconductivity is an electrical resistance of exactly zero which occurs in certain materials below a characteristic temperature [4]. It’s operation at the steady state in constant temperature area. When Rise up resistance and temperature of superconductivity will have been dissipates function. Uni-polar power supply has needed to design discharge energy circuit when superconductor reduces the current. To make use release the energy transfers to external circuit keep the constant temperature with the superconductivity. The superconducting coil wingding has a total length magnetic period of 56.56cm, total magnet length of 478.9cm and vertical (horizontal) magnetic field of 18.7T.  
THPO017 Improvement of Output Current Characteristics for Bira MCOR30 Correction Magnet Power Supply 3373
  • J.C. Huang, K.-B. Liu, Y.S. Wong
    NSRRC, Hsinchu, Taiwan
  The correction magnet power supplies installed at the Taiwan light source (TLS) are Bira Systems’ MCRO 30 power modules, a full-bridge configuration power stage converting the unregulated DC bulk power into a bi-polar current source. The MCOR 30 is theoretically regulated under a very fine control method, with this control method the Bira MCOR 30 should overcome the zero crossover distortion of a standard H-Bridge PWM schemes is used and result in a low frequency noise signature on the output when the magnet current is close to zero. The PWM control circuitry embedded in MCOR 30 theoretically but not really fulfills the purpose what the MCOR 30 want to achieve. With a home-made PWM control circuitry installed into MCOR 30, the width of real pulses can smoothly drop to zero, the MCOR 30 could output current not only with a low frequency noise signature but also much with higher bandwidth of frequency response and much lower Total Harmonic Distortion no matter what output current is demanded.  
THPO018 N+1 Redundancy Power Supply System by Paralleling Current Converter Modules with Digital Regulation Control 3376
  • B.S. Wang, K.-B. Liu, Y.S. Wong
    NSRRC, Hsinchu, Taiwan
  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.  
THPO019 TPS Fast Corrector Magnet Power Converter 3379
  • Y.D. Li, K.-B. Liu
    NSRRC, Hsinchu, Taiwan
  With the increasing demand of the current output accuracy on the TPS(Taiwan Photon Source) project, the MCOR 30 correction power supplies used in current TLS ring are no longer sufficient to meet the TPS requirement. Therefore, power supply group developments a high-precision low output current power supply with a DCCT as an output current feedback component for correction magnets of the future TPS ring. During the research and development experiment phase, we found the DCCT is more possible damaged than the other components. With keeping the architecture of the high-precision low output current power supply, but the DCCT output current feedback component is replaced with a current sensing Shunt resistor. This paper will discuss the design methods of utilizing several different types current sensing Shunt resistor to reduce the cost of power supply and the probability of damage, and improve frequency response of power supply.  
THPO020 TPS Digital Corrector Magnet Power Converter based on FPGA 3382
  • Y.D. Li, Y.-C. Chien, K.-B. Liu
    NSRRC, Hsinchu, Taiwan
  This thesis presents the design and implementation of a FPGA-based fully digital-controlled programmable power supply.  
THPO034 Optimization of a Dual One-turn Coils Kicker Magnet System 3415
  • K.L. Tsai, C.-T. Chen, C.-S. Fann, S.Y. Hsu, Y.D. Li, K.-K. Lin, K.-B. Liu, H.M. Shih, Y.S. Wong
    NSRRC, Hsinchu, Taiwan
  Optimization of a dual one-turn coils configuration for fast kicker magnet system is presented in this report. Emphasis has been made on the: 1) optimization of various possible coils arrangement restricted by the existing available hardware; and 2) synchronization between pulsed currents delivering on the respective upper and lower coils. In the consideration of coils arrangement, good field region is utilized as the guiding parameter while adjusting fixture gap between the coils. As for coil currents timing optimization, fast rise-time and pulse shape preservation are used for practical implementation purpose. Both numerical analysis and experimental data will be presented and discussed.