SIMULATION AND PERFORMANCE INVESTIGATION OF Z-SOURCE INVERTER FOR ELECTRIC VEHICLES

Abstract

With the increasing demand for environmentally friendlier and higher fuel economy vehicles, automotive companies are focusing on electric vehicles, hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and fuel-cell vehicles. The sources in these vehicles are storage device such as bateery or fuel cells. These devices gives the DC Voltages. But for the traction drive of Vehicle AC Motors will be used. For this Inverters must be used. The traditional inverters can be used for this purpose. But the devices like battery, fuel cell, photovoltaic cells gives less amount of DC Voltages but the AC drive requires higher voltages. But VSI and CSI cant boost the voltages in wide range. So additional stage of DC-DC conversion is required which increases cost and decreases efficiency. The Z-Source Inverter can Boost the voltages without additional stage, which increase the system efficiency and reduces the cost. The Voltage Boost operation is possible because of the Impedance network present in the Z-Source Inverter. Different controlling methods are given like Boost Control, Constant Boost Control. The SVM technique has to be modified to use for the Z-Source Inverter. Closed loop voltage control is used in this work. Both the Capacitor voltage and AC Voltage, AC output Currents are taken as reference. The Modified Space Vector Modulation is simulated in closed loop control with various sources like Photo Voltaic Cell, Fuel Cell. The FFT analysis of output voltages and currents is carried out. Hardware is developed in the laboratory. The control scheme is implemented on TMS320F2812 DSP processor based eZdsp.