PWM current rectifying system based on DSP and CPLD

The invention provides a PWM commutating system based on DSP and CPLD. The invention consists of a data collecting circuit, a signal processing circuit, a power drive circuit, a power switch circuit, a USB communication circuit, and a liquid crystal display circuit. The invention has the advantages that the hardware system and the software program of a computer are combined, the design of the hardware system is simple, and the software program can be easily understood. The invention collects three-phase current on the AC side, uses the SVPWM algorithm to improve the power factor on the grid side, is a green commutating system without producing harmonic pollution on the power grid, and uses the IGBT as the switch apparatus of the bridge power circuit. Compared with the GTO and the MOSFET, the invention improves the current carrying capacity and the voltage resistance of the switch apparatus. Two pieces of CPLD chip are designed standby for the circuit producing PWM pulse, and the reliability of the PWM is improved. By the high-speed data processing capacity of the DSP and the CPLD, the real-time performance and the precision of the PWM commutating system are improved greatly.