Research on the battery power model for the power distribution of parallel-series hybrid power system

The key for enhancing the economy of parallel-series hybrid power system is making the engine operate in the best fuel economy zone. Determining the battery power is very important for adjusting the engine operating point and keeping balance of battery capacity. The power distribution strategy for the hybrid power system which makes the engine operate in the best fuel economy zone through battery power regulation is established in this paper. The calculating method of the battery optimal charging or discharging power is present and the battery power model which is the basis for the power distribution strategy is built. The road test results indicate that the optimal power distribution is realized by the power distribution strategy which is based on the fuel economy zone of the engine and the battery power regulation. The engine is operating at the optimal state and the fuel economy is enhanced. Meanwhile, the battery state of charge is balance and the battery is not over-charged or over-discharged. That indicates the battery model is veracious and the battery power calculation is rational which will enhance the life of the battery.