Research on voltage-source PWM inverter based on state analysis method

Abstract

Output voltage waveforms according to all kinds of combination of main circuit structure, load quality and control manner for output voltage are analyzed systematically at ideal condition in voltage-source PWM inverter so that all kinds of existing quality of combination and the rule of influence to output voltage waveform for voltage-source PWM inverter are obtained and a state analysis 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 halfbridge voltage-source PWM inverter is analyzed in detail by the state analysis 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 analysis method, which provides reference for the further research of ideal output voltage waveform and practical output voltage waveform in the voltage-source PWM inverter.