On evaluating the input current distortion with current slopes for single-phase switch-mode rectifiers

This paper presents a simple way to evaluate the distortion level of the input current for a single-phase switch-mode rectifier (SMR). Based on the possible conducting paths of various topologies of SMRs, slopes of the input and command currents are defined to form a slope map. By comparing among the defined current slopes, the causes for distorted input currents are examined according to the slope map. Distorted waveforms of the input currents under hysteresis control are reviewed and classified into three types. Design criteria of the circuit parameters are also studied to reduce the current distortion levels. Simulations are performed and the results show strong conformity to the theoretical analysis