A regenerative energy recovery system for electric vehicles charging a battery at a low speed

Abstract

In this paper, a regenerative energy recovery system for electric vehicles charging a battery at a low speed is proposed. When a permanent magnet synchronous motor driving the electric vehicles is driven by a generator, the generated voltage is controlled to rise or drop by using the L-C resonance circuit. As the circuit only has three capacitors and three IGBTs, the proposed system is very simple. A resonance frequency is found through frequency analysis of the L-C resonance circuit; furthermore, using the resonance effect, a generated voltage control algorithm is proposed. PI duty control in the algorithm raises the generated voltage and reverse PI duty control in the algorithm reduces the generated voltage. The results of simulations and experiments confirm that a remodeled electric vehicle by the proposed system is charged to the driving battery. The results also demonstrate that a small energy storage capacity, which is a disadvantage of the electric vehicle, is largely compensated without increasing the complexity of the electric vehicle.