A feedback-type dead-time compensation method for high-frequency PWM inverters with low distortion and high voltage utilization factor characteristics

Abstract

This paper proposes a new feedback-type dead-time compensation method. The proposed method compensates the output voltage by employing two operations. First, the normal compensation matches the width of the output pulse to that of the input pulse with reduced delay time from the input pulse to the output pulse compared with the conventional method. Second, the short pulse compensation generates an output pulse after a few pulses are input so that the average value of the output signal equals that of the input signal. The voltage utilization factor of the proposed method is almost 100%, because there is no limit to the compensation and the decrease in the fundamental output caused by dead time is eliminated. The experimental results using a 100-kHz input signal show that there is no discrepancy between the output pulse width and the input pulse width. Furthermore, the THD of the compensated output current, when the output frequency is 50Hz, is eliminated, compared with that of the output current without compensation. These results show that the proposed method has low distortion and high voltage utilization factor characteristics. © 2013 The Institute of Electrical Engineers of Japan.