Fuzzy Control Research On Energy Management Of Dual-energy Source Of Pure Electric Vehicles

With the more severe problems of energy shortage and environmental degradation,every country has stepped up efforts to research new energy vehicle. Under the situation, pure electric vehicle with zero emission and no pollution has become the present study focus. The pure electric vehicles using battery as an energy source,has some issues of low specific power and long charging,which has been limited by battery technology and make the development of pure electric vehicles is slow.However, another energy storage element, ultra capacitor with high power storage density,good charge and discharge performance,but it has small specific energy, which makes it impossible to provide power for pure electric vehicles as a single power. Therefore, this paper combined battery with high specific energy and ultra capacitor with large specific power, designed reasonable dual-energy source structure, and established efficient energy control strategy to solve the current shortage of pure electric vehicle with battery.Firstly, this paper selected power system of dual-energy source of pure electric vehicles and analyzed the characteristics of each component. Then, a reasonable power structure was constructed, each component of power system was modeled, and a simulation model of dual-energy source of pure electric vehicle power system was build. Based on fuzzy control theory, fuzzy control strategy of dual-energy source of pure electric vehicles was designed for energy management, fuzzy controller was designed in MATLAB and the corresponding control module was established, and simulation analysis of pure electric vehicles with dual-energy and with single lithium battery was carried out by using ADVISOR software under CYC-UDDS and CYC-US06 working conditions. The simulation results have shown that the dual-energy source system not only improves the efficiency of charging and discharging of lithium batteries and reduces the cycle use time to protect lithium batteries, but also recovers more regenerative braking energy to extend the driving range.Based on fuzzy controller of dual-energy system, with output membership function and fuzzy rule as optimization objects, and with energy consumption and braking energy recovery as optimization aims, optimization model of dual-energy system was established and optimized by particle swam algorithm. Particle swam optimization program was written inMATLAB, and simulation of fuzzy controller before and after optimization was analyzed by conbining ADVISOR software under CYC_UDDS and CYC_US06 working conditions. The results have shown that energy consumption of optimized vehicles reduces with a narrow range under the two different working conditions, which can recover braking energy more efficiently and improve economic benefit of vehicles.