안정파PWM인버어터를 위한 새로운 디지털방식

ave PWM Inverter

As a method to improve harmonics in the voltage source PWM inverter, 5 level stair case wave method is used. The complementary transistor inverter (CTI) bridge circuit has this characteristics. This circuit required synchronous type 3 level PWM signal. In this paper, the 3 phase PWM digital signals within about 10 modulation error of the natural sampling was caculated, and a ROM table out of it for the digital signal of the control system was made. According to this table, the digital control method was proposed, and DTI circuit operated by this method was reviewed. It was confirmed to make V/F control possible by the select modulation ratio to the frequency.