The power supply digital controllers of Shanghai Synchrotron Radiation Facility(SSRF) make use of the PWM(pulse width modulation) wave as the feedback to the power-electrical devices

so as to obtain constant current of high accuracy and stability.The design of PWM wave generation structure in FPGA is good for a compact controller

and the reduction of the usage of Integrated Circuits(ICs) decreases the interference from the noise among the ICs

hence better performance of the controller.In addition

FPGA can be programmed circularly at any time

so as to optimize the structure design and make a maximum use of the advantage of FPGA.As a part of transplanting the complete function of the DSP(digital signal processor/processing)

realizing the generation of PWM wave in FPGA is feasible.In this paper

we report progress in this regard at SSRF.