Thermal Analysis And Heat Dissipation Optimization Of Automotive Electronic Water Pump Controller

The high-power automobile electronic cooling water pump is a key component of the automobile engine cooling system,it is driven by a motor and is not affected by the working condition of the engine.The use of electronic water pump instead of mechanical water pump can accurately control the cooling effect.It is one of the principle ways in which engine fuel consumption and emissions can be reduced.In October 2016,the Strategic Advisory Committee on Energy Efficiency and New Energy Vehicle Technology released a publication that proposed that the average fuel consumption of passenger cars be reduced to 3.2L / 100 km by 2030.The publication said that developing engine thermal management technology is a key priority.Electronic water pumps are an important part of engine thermal management technology as,according to China's Top Ten Engines of the Year Award(2018),most engines used electronic water pump technology.Due to the harsh working environment,high-power automotive electronic water pump power devices and motors have large thermal losses and are difficult to design.As a result,only Magna,Pierburg,Bosch and other international manufacturers currently have mature mass-produced high-power automotive electronic water pump power devices.This thesis leverages the high-power automobile electronic water pump to design a 600 W automotive electronic water pump using an AEC-Q200-compliant ELMOS automotive-grade processor E523.52 as the main control chip.This thesis studies the controller heating,motor winding heating and heat dissipation of the abovementioned water pump for the purpose of determining its compliance with the GM environment and durability standard GMW-3172.First,the heating mechanism of metal-oxide semiconductor field-effect transistor(MOSFET),aluminum electrolytic capacitor,power inductor and motor winding in the controller drive circuit section is studied in depth.The study includes structural characteristics,electrical characteristics analysis and related loss formula derivation.On the basis of the abovementioned study,the MOSFET,aluminum electrolytic capacitor,and power inductor models were determined.The controller parameters and the peripheral circuits of the PMSM drive circuit were optimized to ensure that the controller's heating performance and electromagnetic compatibility performance were balanced to meet design requirements.Second,the conduction path of the power dissipated by the MOSFET and the motor winding is analyzed.The overall heat conduction performance of the pump is modeled by Icepak software.Through simulation,the working condition of the pump in high temperature environment is researched,and the simulation results are used to guide the design of a novel flow channel structure for forced water cooling of the controller and the motor.Finally,according to the GMW-3172 standard,a high temperature(environment 145°C / coolant 125°C)test was performed on the electronic water pump prototype to verify the high temperature reliability of the electronic water pump controller and the motor.The high temperature endurance was performed by a third-party testing organization.Test results show that the thermal performance of this electronic water pump prototype meets the expected requirements.The successful development of the prototype are valuable as they provide important guidance for the design of high-power automotive electronic water pumps and controllers.