In the past two years,
the utilization rate and penetration rate of new energy vehicles have continued to increase. Both foreign and domestic brands have increased the speed of R&D and listing of new vehicles. Statistics show that the overall sales growth rate of the automobile industry in 2020 will be -1.9%, and the sales of new energy vehicles will increase by 10.9%, of which the sales of pure electric vehicles will increase by 11.6%, the sales of plug-in hybrid vehicles will increase by 8.4%, and the sales of new energy vehicles and their All segments outperformed the automotive industry as a whole.
For the popularization of pure electric vehicles, the biggest constraint is the cruising range, which largely determines consumers’ willingness to buy. The cruising range is mainly determined by two factors, one is the capacity of the battery, and the other is the power consumption of the electric vehicle. Relatively speaking, the cruising range is often determined by the factory-rated power, which is also related to the driver’s driving habits. Of course, the most important thing is related to power consumption, where the use of air conditioners is the biggest power consumption point.
It is understood that the air conditioners of electric vehicles are no different from ordinary fuel vehicles. In the cooling mode, they mainly rely on a separate refrigeration compressor to work. The power consumption is mainly concentrated on the compressor’s work. Relatively speaking, the energy consumption of fuel vehicles is more small. When heating in winter, fuel vehicles can recycle the high-temperature cycle generated by the engine’s work to increase the temperature in the vehicle. During this process, the compressor will not be started, so there is almost no energy consumption. Although the various components and systems of electric vehicles also generate a certain amount of heat during operation, the power battery generates the most heat, but this heat cannot meet the needs of air conditioning. Therefore, traditional electric vehicles do not use this heat as The “source” of air conditioning and heating, so in order to provide a heat source, electric vehicles will additionally add heat source components PTC. PTC refers to a positive temperature coefficient thermistor, this kind of resistance is positively correlated with temperature. That is, when the ambient temperature decreases, the resistance of the PTC also decreases, so that after the power is turned on, the current will increase under a constant voltage, and the heat generated by the power will increase.
There are currently two options for PTC heating, plumbing and air heating. The difference is that one is to heat the coolant through the PTC, and then exchange heat with the radiator; and the other is that after the warm air is turned on, the cold air directly exchanges heat with the PTC, and finally the warm air is blown out. Under normal circumstances, the power of PTC will be within 6kW. Corresponding to different functions, the system will control the power of the PTC more accurately. PTC is equivalent to the heat in our daily life. After heating, the fan is used to heat the car. However, when heating, battery consumption increases, and in addition to the colder winter, its own battery capacity is reduced. The combination of the two factors will have a greater impact on the overall battery life of electric vehicles, causing users to have greater concerns And doubts.
In order to solve this pain point, car heat pump air conditioners began to appear. Technically speaking, it is not a new species, but it is still relatively rare in automobiles. This type of air conditioner is mainly based on heat pump technology, which is currently one of the few effective technologies suitable for heating electric vehicles. The entire system consists of four core components, namely: electric air conditioning compressor, four-way reversing valve, heat exchanger and electronic expansion valve. For electric vehicles, the power consumption in winter is mainly the consumption of compressors. Compared with PTC, heat pump air conditioners are more efficient and consume less energy. However, the use of heat pump air conditioners is closely related to the ambient temperature. Once it encounters sub-zero temperatures or extreme cold weather, the work efficiency of heat pump systems is lower and energy consumption will increase. Therefore, some car companies currently adopt the PTC+heat pump mode. In extremely low temperature conditions, PTC is used to heat the room first. After the car has been running for a period of time, the heat generated by the power battery will be recycled, and then the heat pump will be used. Work efficiency, so as to achieve the highest efficiency. portable fire pump
Leave a Reply