Predicted (on-time) equal-charge criterion scheme for constant-frequency control of single-phase boost-type AC-DC converters

Abstract

A new constant switching frequency control method for single-phase boost-type ac-dc converters is presented. The on times of the converter switches in each switching period is determined such that the average input current tracks the reference template in every switching cycle. The problems encountered in achieving smooth and stable operation and the modifications made to overcome them are discussed. The simulation studies done on the converter controlled with t his method, which is given the name predicted (on-time) equal-charge criterion (PECC) method, indicate stable operation at different input-current and voltage levels and power factors. The method was implemented on an insulated gate bipolar transistor (IGBT) converter rated for 1 kVA using a 80 386 processor system for computations. The experimental results are presented and discussed in this paper.