Composite Power Of The Electric Vehicle Simulation Of Control Strategy

It has been generally accepted that the electric vehicles will become the emphasisof the next stage in the development of automobile industry. The electric vehicles,however, using battery as an energy source, has some issues of low specific power、fast charge and so on. Therefore, it has been limited to have a rapid development.Taking charge and discharge into consideration, ultra-capacitor as another energystorage component in the current market is suitable for vehicle power supply. But itsspecific energy is too low, which leads to discharge ability not available for itssustainable use. If, combined with the two, making a best use of high specific energyof battery and high specific power of ultra-capacitor, the limitations as a single energystorage device can be solved better.This paper starts from constructing the connection mode of composite power andestablishing a reasonable adjustment of energy, and next, analysis the usability ofbattery and ultra-capacitor both as vehicle power supply and their respectivecharacteristics, and the role of DC\DC converter in composite power. What’s more,according to the characteristics of battery and ultra-capacitor and the control lawdesigned in the paper, make two control strategies based on the theory of logicthreshold control and fuzzy control and set up a corresponding composite powermodel. Apart from this, have a second development for the simulation softwareADVISOR, and this simulation is based on the composite power mode to build twopure electric vehicle models. Last but not least, have an analysis for the result. First,through the comparison of demand speed and simulation speed, concludes that underthe two control strategies, can meet well the power demand of car. Second, throughmonitoring current situation in the process of simulation battery and ultra-capacitor,concludes the feasibility of constructing composite power thoughts. Last, through thecomparison of battery output current under different control strategies, concludes thatthe fuzzy control strategy can adapt better to the demand conclusion of compositepower system control.