One-cycle controlled single phase ac chopper

Ac choppers have been widely used in industry applications such as lighting dimmers, industrial heater, soft-starting of induction motors and speed control of pumps, and their control method often adopt voltage instantaneous value PI control. This method has the fault of bad dynamic response and the distortion of output voltage at zero-crossing. One-cycle control technique can solve this problem. One-cycle control is a nonlinear control method which has fast transient response and good tracking performance. A single phase ac chopper with one-cycle control method is presented; the basic operational theory and control method are discussed in this paper. Finally, simulation waveforms and experimental results are given. The experimental results demonstrate the effectiveness of this control technique.