Analysis of the battery performance in hybrid electric vehicle for different traction motors

Hybrid electric vehicles (HEVs) have gained immense popularity due to the rapidly increasing stringent emission norms and global environmental concerns. Unlike conventional vehicles, the presence of high charge sustaining rechargeable energy storage system (battery) in HEV distributes the vehicular power demand, thus considerably reducing the size of the internal combustion engine and in turn the fuel consumption. The HEV is equipped with a high power traction motor that is powered by the battery or the generator and is directly connected to the transmission. This motor also has regenerative braking capability, thus transferring energy back into the battery which otherwise would have been wasted in the form of heat. The present automotive industry is using different types of motors for HEV application, depending upon the extent of their use and power requirement. The battery performance is a function of the motor operation. In this paper, the characteristics of different types of traction motors will be discussed. DC and induction motors will be then tested against a designed electric circuit model of battery in order to determine the respective charge-discharge characteristics. The designing of the battery management system is dependent on the analysis of this charge-discharge variation for determining the precision battery parameters such as voltage and current limits, and permissible state-of-charge.