Research on the control method of electronic expansion valve in automotive thermal management system

In response to the problem of overheating and unstable temperature fluctuations in the electronic expansion valve in the car thermal management system, a control model based on fuzzy PID was developed by analyzing the working principle of the electronic expansion valve. The model was then used for thermal simulation in the entire vehicle thermal management system. The simulation results show that, at an ambient temperature of 25°C and a battery heating power of 8000W, when the cooling condition is activated and the compressor starts at a speed of 1000 rpm, the electronic expansion valve is controlled by the algorithm, resulting in the overheating starting from 0°C and reaching a maximum of 13°C, and eventually stabilizing at around 5°C with an overshoot of less than 5%. At the same time, the temperature of the battery pack is maintained at 15°C, meeting the requirements for the overall vehicle thermal management performance.