Z-Source Inverter-based Induction Motor Drive System

Traditional induction motor drive system using voltage source inverters and current source inverters as a power conversion unit. The two inverter topologys both has their conceptual and theoretical limitations, resulting in high-cost, low efficiency and anti-interference ability in some practical applications. The Z-source inverter overcomes the limitations of the conventional voltage source inverter and current source inverter, it also provides a new option for power conversion.In this thesis, the Z-source inverter is used in induction motor drive system based on its unique strengths. The basic principles and control methods are introduced. The non-normal working state of Z-source inverter and the methods of restrain are also discussed. The proposed induction motor drive system is divided into DC and AC two parts which can be analysised and controlled separately. The DC part is controlled by the outer peak DC input voltage loop of PWM inverter and the inner inductor current loop.The proposed induction motor drive system based on Z-source inverter controlled by the V / f control or slip frequency vector control system. The simulation results show that the Z-Source Inverter-based Induction Motor Drive system ensures induction motor working on light-load condition and control the speed change smoothly. The impact of voltage sag and load torque change can be restrained. The system presents great dynamic performance and anti-disturbance capacity.