Because electric vehicles do not use the engine (internal combustion engine) as the power source of the vehicle, their air conditioning system cannot use the engine waste heat to achieve the effect of heating and defrosting. Therefore, the new energy vehicle air conditioning system adds an
electric scroll compressor and heating system compared to the traditional fuel vehicle air conditioning system.
In terms of refrigeration principles, the EV air conditioning system is basically the same as that of traditional fuel vehicles. The difference is mainly manifested in the driving method of compressor and the source of warm air. Electric vehicles use electric compressors for refrigeration, and
high voltage electric air-conditioning compressors are driven by batteries.
Heating is more complicated and critical for new energy vehicles, because the heating source of conventional vehicles air-conditioning system is mainly provided by engine coolant, which consumes almost no power, simple and efficient.
But for new energy vehicles, it is more troublesome.
Heating in new energy vehicles usually use electric heating methods. Electric heating methods are also divided into two types:
One is to heat the coolant to provide heat to the warm water tank through refrigerant circulation;
The other is to directly heat the air passing through the evaporator to achieve heating (PTC heating or heat pump).
PTC heater can be simply understood as a large resistance. When there is current passing through Q=I2R, heat will be generated. The only problem of PTC heater is with low heating efficiency and large energy consumption. In extreme winter conditions, the electricity consumed by electric air conditioners is almost half of the vehicle's cruising range. Therefore, many drivers dare not turn on the air conditioner in winter. What is worth looking forward to is that
heat pump electric compressor have attracted more and more attention due to their higher heating efficiency. Guchen EAC and major OEMs are actively developing heat pump compressors
For hybrid electric vehicles, due to its control strategy, the engine cannot be used as a power source for refrigeration compression or a heat source for heating at any time. Therefore, the air-conditioning systems of pure electric vehicles and hybrid vehicles are not exactly the same. The source of the warm air is the engine coolant as the heat source when the engine is working; In the EV mode, the electric heating PTC is generally used to provide the heat source.
