Analysis of conduction losses in inverters

A conduction-loss-evaluation method which is important in inverter design is presented. The method is based on the probability of inverter switching devices receiving ON signals. Since it does not require knowledge of the exact switching patterns of the power devices, the proposed method is especially useful for inverters in which the switching patterns cannot be predetermined. To show the general applicability of the proposed method, the expressions for conduction losses in resonant DC link, hysteresis current-controlled and sinusoidal PWM inverters are derived. A comparison of conduction losses in these inverters is presented. The influence of load power factor on conduction losses is investigated. The experimental results are included to verify the proposed method