Research On Engine Electro-hydraulic Mix-drive Cooling System

The functions of the vehicle engine cooling system maintain the temperature of theengine into the suitable range. The power and economy of the vehicle is affected by thevehicle engine cooling system. The development of engine cooling system technology isimportant to improving the overall performance of the vehicle, easing the energy shortageproblem and reducing the pollution of the environment. Intelligence and energy conservationis the direction of the engine cooling system development.With the use and development of automotive electronic control technology in the enginecooling system, the engine cooling system response to changes in working conditions is moresensitive, less energy,better cooling effect.The electro-hydraulic mix-drive cooling systemresearched in this paper is combined with hydraulic drive and control technology andautomotive electronic control technology. In the electro-hydraulic mix-drive cooling system,the hydraulic system transmits power and the electronic control unit keeps theelectro-hydraulic mix-drive cooling system intelligent. According to the temperature of enginethe electronic control unit is able to control the pressure in the hydraulic system, changingpower transmitted, making the cooling system cool the engine properly.The main content of the paper includes the overall design of the structure of theelectro-hydraulic mix-drive cooling system, the design of the hydraulic system, selectingcomponents of the hydraulic system, the design of the electronic control unit, selecting themodel of the electronic control unit. The specific contents include calculating the heatgenerated by the engine, calculating the circulating volume of cooling water, calculating thecooling water pump power, calculating the rated torque of the cooling water pump,calculating the volume of cooling air, calculating the power and rated torque of the fan thathydraulic motor drive, correcting cooling system parameters, selecting the model of thehydraulic motor, selecting the model of the hydraulic pump, selecting the model of theelectro-hydraulic proportional relief valve, selecting the model of the temperature sensor,selecting the model of the current transmitter, selecting the model of the current amplifier,selecting the model of the relays, selecting the model of the single chip microcomputer,designing ECU A/D module program, designing ECU D/A module program, setting fuzzylinguistic variables, setting fuzzy language value, setting membership functions, setting fuzzycontrol rule table, calculating fuzzy control query table and so on.With the completion of the above work, the electro-hydraulic mix-drive cooling systemis tested by test bench.According to the test results under different conditions, theelectro-hydraulic mix-drive cooling system is ameliorated untill it achieves the desired effect.