The Harmonics Control Method of Inverter in Induction Heating Power Supply

In this paper, the induction heating power supply adopting cascaded multilevel inverter was the study object. For improving the quality of output voltage in induction heating power supply inverter, a harmonics control mean of output voltage by selecting switching angles were presented. The harmonics equation system of output voltage in two modules cascaded multilevel inverter were established based on the Fourier expression of the output voltage. Based on the work characteristic of induction hearting power supply, the calculation method of eliminating harmonics and the reasonable advice about switching angles were given. Simulation and experiment results shown the total harmonic distortion (THD) of output voltage can be reduced by adopting the harmonics control mean presented in this paper.