A hybrid structure using phase-controlled rectifiers and high-frequency converters for magnet-load power supplies

Thyristor rectifiers are still the preferred choice for large magnet power supplies. However, large harmonic voltages, resulting in large current ripple, and slow dynamic response are major drawbacks of these converters. This paper presents a topology and a control technique for hybrid large-power high-precision magnet power supplies. The system consists of a phase controlled rectifier connected in series with a high-frequency PWM converter. The rectifier is designed to handle the main output power and the PWM converter is used only for harmonics cancellation and error compensation. A feedforward control scheme is proposed to ensure that the desired power sharing is maintained during both the steady state and transient operations. The operating principles of the proposed structure are discussed in the paper, and the results from a 1 kVA experimental setup are provided to validate the proposed topology.

[1]  K. N. Mortensen,et al.  Feasibility Study of AC- and DC-side Active Filters for HVDC Converter Terminals , 1989, IEEE Power Engineering Review.

[2]  Toyoki Kitayama,et al.  High-speed, high-accuracy magnet power supply using FET chopper for synchrotron facility , 1989, Proceedings of the 1989 IEEE Particle Accelerator Conference, . 'Accelerator Science and Technology.

[3]  Shashi B. Dewan,et al.  A low ripple power supply for high current magnet load , 1992, Conference Record of the 1992 IEEE Industry Applications Society Annual Meeting.

[4]  Jose Antenor Pomilio,et al.  A novel topology for the bending magnets power supply at LNLS , 1992 .

[5]  D. Wolff,et al.  Very High Precision Current Regulated Power Supplies for the Fermilab Antiproton Source , 1985, IEEE Transactions on Nuclear Science.

[6]  H. Akagi,et al.  A new approach to harmonic compensation in power systems , 1988, Conference Record of the 1988 IEEE Industry Applications Society Annual Meeting.

[7]  Fang Zheng Peng,et al.  A Combined System of Shunt Passive and Series Active Filters , 1990 .

[8]  Hans W Isch,et al.  Switch mode power converters; present and future , 1989, Proceedings of the 1989 IEEE Particle Accelerator Conference, . 'Accelerator Science and Technology.

[9]  R. Dwinell,et al.  A RASTER SCANNING POWER SUPPLY SYSTEM FOR CONTROLLING RELATIVISTIC HEAVY ION BEAMS AT THE BEVALAC BIOMEDICAL FACILITY , 1987 .