The Hybrid Electronic Vehicle Fuzzy Logical Control Strategy Based On Road Condition

The HEV can save a lot of energy by its characters of storing the energy in the batters and give out when there is a high power demand. It is a very good direction for future explore. But,its actual performance is not so satisfy the expectation because of the road condition effect and the drivers’ habit. The HEV system is an experts system.its mode is closely bound up with the road condition and the drivers’ performance.And, the drivers’ performance is so much randomly,the control strategy don’t want to interfere and control the tempt of driver in case it will cause accidents. So,this thesis is just discuss about the effect of road condition as follow aspects:1,Road condition recognitionThe vehicle control unit can receive messages came from motor controller,generator controller,clutch,engine,air condition,DC/DC,DC/AC and other auxiliary devices,and transmit to the vehicle CAN line,according to read those messages to unscramble information like:car stop sign,velocity,road length,gradient,bus voltage,clutch location,engine speed,motor speed,motor torque,vehicle mode and so on.2,GPS assembled with the vehicle informationInstalling GPS receiver can connect the database to get traffic flow and traffic average speed info. and in the same time up loading road condition and vehicle info. to the web database by GPRS signal to help the technical person to do analysis and data digging.3,Build the neutral net modal based on vehicle dataBuild the BP neutral network mode,the input info. are road related and part of vehicle related. The output are fuel consume,clutch action times and engine start-stop times per segment.the sample info came from vehicle data collection and extraction.4,Multi-objective optimization based on particle swarmIn order to release the clutch action and engine start-stop counts. Increase the clutch and engines’ service life.build a three variable quantities multi-object optimization.we can get a set of threshold values. Based of those data to get a multi-object optimization about vehicle mode ratio to reach the demand of good fuel consume and lease clutch and engine actions.5,Fuzzy logical control strategy designTo build a road condition based vehicle control strategy by the road condition information and vehicle mode ratio information got by the particle swarm optimization method.put fuzzy logical control information into those variable can be manipulated by the fuzzy logic.lower the priority of fuzzy logic to meet the demand of separation and reunion the fuzzy logic.