Study of Voltage-Source PWM Inverter Based on State Combination Method

A state combination method is presented for a voltage-source PWM inverter. Main circuit states are obtained through the on-off state combination of switch devices, and valid main circuit states are determined according to the characteristic of the voltage-source PWM inverter. The ideal output voltage waveform of the voltage-source PWM inverter is determined by the combination of all kinds of valid main circuit states. The output voltage waveform of a single-phase half-bridge voltage-source PWM inverter is analyzed in detail by the state combination method and the corresponding control strategy is obtained, which is extended to the single-phase full-bridge voltage-source PWM inverter and the three-phase bridge-type voltage-source PWM inverter. According to the analysis of dead-time problem, non-dead-time control strategy is presented. The relation between working and output voltage waveform of the main circuit of the voltage-source PWM inverter is analyzed in nature and the control strategy of the output voltage waveform of the voltage-source PWM inverter is improved by the state combination method, which establishes the foundation for the further research of the practice output voltage waveform of the voltage-source PWM inverter