Stabilizing the Average-Current-Mode-Controlled Boost PFC Converter via Washout-Filter-Aided Method

The average-current-mode-controlled boost power-factor-correction (PFC) converter may exhibit instability at the line frequency. This nonlinear phenomenon is undesirable. The time-delay feedback control method may stabilize the boost PFC converter by introducing a digital circuit. The digital circuit is difficult to implement. The second-order filter method can also control the instability, but its implementation is a little complex. In this brief, the washout-filter-aided method is proposed to stabilize the boost PFC converter. The dynamic-phasor-based harmonic averaged model of the converter is derived by applying the harmonic balance method to the averaged model. The equilibrium point of the first-order harmonic model is the origin. This equilibrium point may be stabilized by appropriately choosing the parameters of the washout filter so as to stabilize the PFC converter. Numerical simulation verifies the effectiveness of the washout-filter-aided method.