Hybrid permanent magnet generators for electric vehicle applications

In transportation systems, the energy consumed by vehicles is considered a primary source of energy consumption and pollutant emissions. Some of the pollution problems have been resolved by the development of electric vehicles (EVs). There are some drawbacks related to EVs due mainly to limited driving range, excessive volume capacity of batteries, and long time battery charge. Therefore, hybrid electric vehicles (HEV) are developed to increase vehicle driving range with maintaining a low fuel consumption and emission. This paper presents one of the hybrid excitation synchronous machine topologies, which have been reported in the literature that will replace permanent magnet synchronous machine (PMSM) in HEVs to optimize their hybrid capability and get a simple control over their constant flux linkage to maintain constant output voltage during load transient, which will decrease fuel consumption and emission. This HESM has both permanent magnet (PM) and wound field (WF) rotors coupled on the same shaft. HESM rotors are analyzed individually by 2-D FEA program to get their optimal design before coupling them on the same shaft. The equivalent circuit representation of PM and WF synchronous machine 2-D models are established. PMSM numerically obtained back EMF and waveforms results are compared with an experimental measurement.