Design Of Control System Of Electronic Control Water Pump For New Energy Vehicle

The development of new energy vehicles has become the inevitable trend of the sustainable development of human society,and the performance of the pump control system is also a more important part of the new energy vehicle operation.In order to solve the problems of the traditional mechanical water pump,such as high dependence on the engine,low efficiency and serious wear and tear.In this paper,based on the method of model code generation,according to the process of "strategy design,simulation analysis and bench validation",the research of new energy vehicle electric water pump control system has been carried out.The key technology of the electronically-controlled pump control system is the motor,so this thesis has mainly studied the control strategy of the brushless DC motor(Brushless Direct Current Motor,BLDCM).First,the domestic and foreign research status of new energy vehicle pumps and brushless DC motors are introduced in this thesis,and the significance of this study is analyzed.The structure and working principle of the brushless DC motor are analyzed,and according to this,the mathematical model of the motor is established.Secondly,the main phases of the operation of brushless DC motors are described,the main requirements of the electronically-controlled water pump control system are analyzed,and the start-up control strategy is proposed according to the features of the brushless DC motor start-up phase.After the motor is successfully started,a speed and current double closed-loop control strategy based on PID control algorithm is proposed.According to the characteristics of the motor operating environment,the motor speed control strategy is designed under different temperature and different pulse width modulation(PWM).Finally,the protection strategy of the brushless DC motor is developed and designed for the possible failure of the motor.The process of starting,running,and fault protection of the motor are reasonably analyzed,and smooth start-up and commutation of the motor and no damage at the occurrence of a fault are guaranteed.Based on MATLAB/Simulink,a control strategy model is built to prepare the control strategy for simulation debugging and bench verification.Finally,the code is generated through MATLAB/Simulink's auto-generated code function,the code generated by the model is integrated into the MC9S12ZVML12 chip by Codewarrior software for simulation and verification.The results show that under the control strategy,the motor can achieve a smooth start-up operation and achieve self-protection under various fault conditions.Real-time monitoring and modification of key motor performance parameters in the running state through CAN communication can be realized by calibration and debugging of control strategy parameters based on CANoe.Finally,the electronic control water pump control system is verified by a bench test.The results show that the relationship between voltage,flow,head of delivery and pump efficiency acquired through experimental data is to meet industry standards.which shows that the performance of the water pump control system is reliable,and which proves that the new energy electronic control pump control strategy designed this time can meet the actual performance requirements.