A novel adjustable-speed system based on Z-source inverter

This paper proposes a novel PWM current source rectifier -Z-source inverter adjustable-speed system (abbreviated as PWM CSR-ZSI ASD). The operating principle, control strategy and circuit analysis have been given. The benefits of the presented ASD system have been analyzed in detail. The proposed PWM CSR-ZSI ASD system have many advantages, it providing a bidirectional power flow, maintaining the unity power factor, reducing the input line current harmonics, providing ride-through during the voltage sags and voltage swells without any additional circuits, and makes the inverter modulation index high during low-speed operation. Analysis and simulation results will be demonstrate these features.