New approach FPGA-based implementation of discontinuous SVPWM}

摘要

The discontinuous space vector pulse-width modulation(DSVPWM) is a well-known technique offering lower switching lossesthan continuous SVPWM. At the same, average switching frequency, or aswitching frequency 1.5 times higher than utilized in continuousSVPWM, the discontinuous SVPWM results in lower current harmonicdistortions than that obtained in continuous SVPWM at high modulationindices. This paper is concerned with the design and realization ofnew FPGA approach based a 5-segment discontinuous SVPWM operated at 40kHz switching frequency. It will be shown that the implementation ofthe discontinuous SVPWM utilized in FPGA, to execute some complextasks, is simplified through this new straightforward approach. Forexample, the judging of sectors, the computation of on-duration orfiring pulses to control the switching of power switching devices canbe executed much simpler with the proposed arithmetic logics ordigital calculation in FPGA. In this way, the sampling frequency andhence switching frequency be increased. The SVPWM scheme has beenimplemented successfully based on APEX20KE Altera FPGA consideringhardware resource saving. The validity of the proposed scheme hasbeen tested experimentally to drive a 1.5 kW induction machine withlow current harmonic distortions.