串联式静液传动混合动力车辆功率管理策略

Power Management Strategy of Series Hydrostatic Hybrid Vehicle

针对串联式静液传动混合动力车辆中,发动机工作状况独立于车轮负载情况,储能元件功率密度大、能量密度低的特点,提出了基于随机动态规划方法的发动机功率管理策略,对发动机工作点进行优化控制。根据传统车辆性能参数配置了串联式静液传动混合动力车辆,以降低燃油消耗为优化目标,对原发动机和减小装机功率的发动机工作情况进行仿真。结果表明,采用该控制策略进行优化控制,发动机燃油经济性大幅提高,氮氧化物和烟尘排放明显减少,并且在城市工况下,较小装机功率的发动机在氮氧化物排放性能上优于原发动机。

The engine works independently to the wheels load conditions and the energy recovery units have characters of high power density and low energy density in series hydrostatic hybrid vehicle.A stochastic dynamic programming based engine power management strategy was proposed according to the above characters to optimize engine＇s working points.A series hydrostatic hybrid vehicle was configured based on the performance parameters of traditional vehicles.Aimed at reducing fuel consumption,the working conditions of the initial vehicle＇s engine and the lower power engine in hydrostatic hybrid vehicle under the proposed strategy were simulated.The simulation results show that（1） the engine＇s fuel economy increased greatly,NOx and soot emission decreased obviously under the proposed strategy;（2） during the city driving cycles,the lower power engine did better in NOx emission characteristic.