Research And Development Of New Electronic Fan Controllers For Passenger Cars

The automotive electronic fan is one of the core components of engine thermal management and an important measure of reducing fuel consumption in fuel vehicles.In 2016,the State Council issued the "Energy Conservation and New Energy Vehicle Industry Development Plan".The plan clearly stipulates that the overall goal of China's automobile energy-saving standards is that the average fuel consumption of new passenger cars will reduce to 5.0 L/100km in 2020 and 4.0 L/100km in 2025.The advantages of the electric cooling fan replacing the traditional cooling fan are following:first the engine power loss can be reduced by 5%to 12%,second the heat transfer loss and the excessive wear under low temperature conditions of the engine can be reduced,third the comprehensive fuel saving index can be up to 10%.Therefore the electric cooling fan has become the replacement product of automotive engine cooling fans.In this dissertation,the automotive-grade processor MLX80153 is used as the main control chip,and an electronic fan controller with a power of 520W is designed and implemented.The controller receives the control signal of the vehicle electronic control unit(ECU)through the PWM interface,and realizes the stepless speed regulation of the cooling fan.The controller has comprehensive protection functions,including back pressure protection,over voltage protection,under voltage protection,short circuit protection,stall protection,open circuit protection and over temperature protection,and can send fault codes to the ECU in real time.Through careful design,the controller has good electromagnetic compatibility(EMC)performance,environment and durability,meeting the requirements of GMW3097 and GMW3172,respectively,while reducing the heat generated by the controller itself.This dissertation also designed an electronic fan test bench,which can be used for speed control and protection function testing of electronic fans.The test results show that the electronic fan controller designed in this dissertation meets various functional and performance requirements and achieves the expected goals.