Abstract
In this paper, a proposed electric drive system for a three-phase induction motor is presented. The proposed drive system is suggested for a golf car as one type of electric vehicle. The suggested system consists of three similar single-phase buck−boost converters. Hence, each single-phase buck−boost converter is used as a buck−boost inverter and is used to energize only one phase of the induction motor. The suggested system has the advantage of high reliability, as it can deal with different fault conditions such as battery and motor winding faults. The suggested electric drive system depends on a buck−boost converter which gives variable voltages as well as variable frequencies. Thus, variable speeds of the electric vehicles can be easily achieved. A variable DC voltage (positive or negative) can be achieved at the output of the adopted buck−boost converter, which is considered another advantage of the proposed drive system. This DC voltage can be used to achieve braking of the induction motor used to drive the electric vehicle. Therefore, this advantage can be used instead of ordinary mechanical braking to increase vehicle reliability. To demonstrate our proposed idea, a simulation study is presented. The simulation is carried out using Power Simulation Program (PSIM) software. The simulation study takes into consideration the performance of the adopted buck−boost converter under different conditions to present its advantages. Furthermore, a performance study of the suggested induction motor drive system is carried out under different conditions ranging from healthy to faulty conditions to test system reliability. For more illustration, an experimental prototype of the adopted buck−boost converter is built, and its performance is studied. From all the obtained results, the efficacy of the proposed system is demonstrated.