Development of a route information-based control algorithm of a range extender for an RE-EV

In a range-extended electric vehicle (RE-EV), the system efficiency decreases when the engine power is transmitted to the driving motor through the battery due to the charging and discharging energy conversion efficiency. To improve the system efficiency, a control algorithm is proposed using the route information. The control algorithm calculates the threshold power based on the battery charging amount and the demanded vehicle power from the target route. Using the threshold power, more engine power can be transmitted directly from the engine to the driving motor without charge and discharge process through the battery. It was found that the proposed algorithm reduces the fuel consumption of the target RE-EV, compared with the existing CD/CS control.