EQUIVALENT TRANSFER FUNCTION GENERATOR OF MAGNET POWER SUPPLY USING DSP

DC active filter is operating to reduce the current ripple of the KEK 12GeV PS main ring quadrupole magnet power supply. However, transient response restricts the effective area to alive the active filter during injection and extraction period since the transient response becomes oscillatory with decreasing amplitude. In order to operate the active filter for all period, the real ripple component except transient response signal should be detected. Equalizer, which made it possible to realize the equivalent transfer function using DSP (Digital Signal Processor), will assist to reject the transient response. General description of the DSP control system, algorism, electric devices and experiment performance of equalizer will be presented