Introduction of New Energy Vehicle Cooling System
Introduction of cooling system
The essence of cooling is heat transfer. There are three ways of heat transfer: heat conduction, heat convection and heat radiation. And the way the car's cooling system radiates heat is heat conduction.
Conduction: in non-uniform heating of the object, heat from the high temperature by the molecules of the object gradually transferred to the low temperature phenomenon, known as heat conduction. In this way the heat exchange continues until the temperature of the whole body is equal. Conduction can occur between solids, liquids, and gases, and it must be accomplished by making objects contact with each other.
Depending on the heat transfer medium, the cooling system can be divided into three categories:
Classified by cooling medium:
Water cooling system: heat conduction medium is coolant
Air cooling system: heat conduction medium is air
Direct cooling system: heat conduction medium is refrigerant
Ever since KARRH Benz invented the first car in 1886, no matter what kind of car was being developed, no matter what form its power source took, unless the perpetual motion engine was actually invented, otherwise, the car must need cooling system, which is an important part of the car powertrain and is responsible for the temperature control of the fuel engine to ensure that it works in a suitable temperature range Has the significant influence to the automobile's power, the economy and the reliability. After 1910, oil engine was widely used in automobiles, including a small number of LPG or natural gas engines, while most of the traditional diesel vehicles used water cooling system.
The water cooling system of internal combustion engine vehicles usually includes cooling engine water jacket, radiator, water pump, fan, wind shield, thermostat and auxiliary water tank, etc. , the cooling fluid is used as the working medium of the whole system. Based on the basic principles of engineering thermal physics, cooling, supercharged intercooling and air conditioning systems can also be treated in a unified way when modern thermal management theory and tools are applied to research and analysis. The components involved will be extended to intercoolers, warm air heat exchangers and condensers.
The new fuel (such as natural gas, LPG) in the new energy vehicle cooling system and traditional vehicles no difference, but with the emergence of electric vehicles, the cooling systems of electric vehicles are further complicated by the need to cool power components such as batteries, motors, Motor controller and Chargers.
Electric drive cooling systems are generally similar to conventional cars, because the upper limit of the operating temperature of power devices such as motors, electronic controls and Chargers is higher than the ambient temperature, so heat can be directly emitted to the surrounding atmosphere, the system usually includes parts such as motor/electronic water jacket, charger water jacket, radiator, electronic water pump, electronic fan, and expansion tank water tank, etc. ,
the battery cooling system is a new addition to the traditional electric vehicle, because the temperature has a great influence on the battery performance, so the heat management of the battery has always been a hot issue in the research of the main engine factory and the battery factory since the rise of the electric vehicle industry, at present, there are 4 kinds of battery cooling methods on the market: including water cooling system (Tesla) , Air Cooling System (Kia Soul) direct cooling system (BMWI3) and phase change cooling (new material) . As the range of electric vehicles is getting longer and longer, and the total amount of battery power on a bicycle is also increasing, more and more vehicles are adopting water-cooling systems for safety and economy reasons, such as heat pump air conditioning technology can be more mature, then the direct cooling method will be more widely used.
