A Study On Control Strategy For Extended Range Electric Vehicle

The development of the global auto industry is rapid, and the growth of auto productionand sales is high. However, the growing number of cars and the daily consumption of oilresources will inevitably be a contradiction. In order to alleviate this contradiction, thetransformation of the vehicle energy is imperative. As a result of zero pollution and zeroemissions, pure electric vehicle is regard as "clean car", and it is the pursuit of China’sautomobile industry. But in the actual development, restrained by battery technology,imperfect charging facilities and other reasons, the extended range electric vehicle is notwidely used. As a kind of hybrid car, the extended range electric vehicle can solve theproblem of short driving range that pure electric vehicles continued. At the same time, fuelconsumption is reduced significantly relative to the internal combustion engine. Itsapplication prospect is good.From the point of view of improving the fuel economy, meeting the vehicle powerperformance and reducing environmental pollution, the paper carries on the research on thecontrol strategy of extended range electric vehicle. The research contents are as follows:(1) According to the basic parameters of extended range electric vehicle and the desiredperformance index, the vehicle power train parameter is designed and calculated. Throughapplying Cruise software to establish the vehicle model, and dynamic simulation test is usedto show that the model can meet the requirements of the vehicle power performance index.(2) To analyze the characteristics of traditional constant power control strategy ofextended range electric vehicle and the influencing factors of pure electric vehicle mileage,the engine working curve is determined. Two kinds of control strategy are designed: theeconomy (ECO) and power (SPORT). The Cruise and Matlab/Simulink is applied to makeco-simulation experiments that verify the control strategy. And to make comparison with theconstant power control strategy in economy, power performance and emission performance.(3) In the dSPACE hardware environment, the incremental PWM modulation controlmotor of extended range electric vehicle is determined. According to the signal conversionprinciple, signal with current and voltage detection, signal receiving and output functionconversion experiment board can be designed. Through simulation by the Proteus software,the function of the signal conversion experiment board is verified.Research shows that: When the vehicle is in the city conditions (such as the NEDCconditions), if ECO control strategy is selected, compared to the SPORT and the constantpower control strategy, the fuel economy performance is best and in the minimum CO2emissions. When the vehicle is in high speed and complex conditions (such as mixedconditions), if the SPORT control strategy is selected, compared to the ECO and the constantpower control strategy the best performance, the fuel economy is best and dynamicperformance is optimal.