The principle of heating for new energy vehicles is mainly based on the following methods:
1. Heat pump air conditioning system: The heat pump air conditioning system uses the reverse operation of the refrigeration cycle to achieve heating. The system includes main components such as compressor, condenser, expansion valve, and evaporator. The compressor sucks in low-temperature and low-pressure refrigerant and compresses it into high-temperature and high-pressure gas. The high-temperature and high-pressure refrigerant is converted into high-temperature and high-pressure liquid in the condenser through the action of external air or other cooling media, while releasing a large amount of heat. After the high temperature and high pressure liquid is depressurized by the expansion valve, it enters the evaporator, where the refrigerant converts from liquid to gas and absorbs the heat inside the vehicle, achieving the heating effect. This heating method has a high energy efficiency ratio, but its heating performance may decrease in low-temperature environments.
2. PTC electric heater: PTC electric heaters use the heat generated by current passing through PTC materials to heat up. PTC materials have a positive temperature coefficient characteristic, which means that as the temperature increases, their resistance value increases sharply, thereby achieving self temperature limiting function and preventing overheating. PTC heaters have a simple structure and fast response speed, but their energy consumption is relatively high and their thermal energy utilization rate is low, which has a certain impact on the range of new energy vehicles. Despite these drawbacks, PTC heaters have been widely used in pure electric vehicles due to their advantages such as low cost and fast heating.
3. Waste heat utilization: Components such as motors and electronic control systems in new energy vehicles generate a large amount of waste heat during operation. By using heat pipe heat exchangers, phase change heat storage devices, and other devices, this waste heat can be effectively collected and used for heating inside the vehicle. This approach not only improves the overall thermal efficiency of the vehicle, but also reduces reliance on traditional energy sources, making it an important development direction for heating technology in new energy vehicles.
The heating of new energy vehicles mainly relies on methods such as heat pump air conditioning systems, PTC electric heaters, and waste heat utilization. Among them, heat pump air conditioning systems have become the mainstream choice due to their high energy efficiency ratio, while PTC electric heaters are widely used in mid to low end vehicle models due to their simple and fast characteristics. Meanwhile, the development of waste heat utilization technology has also provided more possibilities for heating new energy vehicles.