An Energy-saving Thermostat Controller for Electric Vehicle Air-Conditioning System (電動空調省能化恆溫控制策略)
- In the past few years, most of the vehicle manufacturers invest a lot of resources in developing the related electrified subsystems and technologies for improving the electric vehicle performance. The air-condition system is one of the electrified subsystems which provides a comfortable feeling to the passengers. The energy consumption of the air-condition system is only second to the electric propulsion system which could significantly decrease the electric vehicle mileage. Therefore, an energy-saving thermostat controller is developed by Automotive Research and Testing Center to reduce the power consumption. The controller includes a variable–frequency controller for the electric compressor and the fans of the radiators, and a thermal load estimator to calculate the demanded AC power based on several parameters, i.e. the cabin temperature, the environment temperature and the set temperature, and etc. The controller will tune the working conditions of the components to provide the output power as estimated result and avoid unnecessary electric power consumption. In this research, the concept of “felt air temperature” is added into the thermostat controller to help saving additional electric energy. The felt air temperature calculates with a semi-empirical equation based on the cabin temperature, the air velocity from the ventilation outlet and the humidity inside the cabin, and the result is used to tune the working conditions of the active components for saving more energy. Since the felt air temperature could be achieved with a higher air temperature, the thermal load would be lower and the system energy consumption could be decreased. An experiment was executed and the result shown that the COP (coefficient of performance) of the system could be increased by 10% which could improve the efficiency of energy resource.
- IA-04-0019 (409K)