Pure electric vehicles are highly integrated scientific and technological products involving multiple disciplines such as machinery, electronics, electricity, and microcomputer control, and correspond to traditional fuel vehicles. In the context of the increasingly prominent global greenhouse effect and energy issues, national environmental protection regulations are becoming stricter, so the demand for low-polluting vehicles is bound to increase. With the continuous emergence of various high-performance batteries and high-efficiency motors, people have begun to research and continue to develop pure electric vehicles with zero or ultra-low pollution emissions.
1) Definition of pure electric vehicle
A pure electric vehicle refers to a vehicle that is powered by an on-board power supply and driven by a motor to drive wheels, and meets the requirements of road traffic safety regulations. Generally, high-efficiency rechargeable batteries are used as the power source. Pure electric vehicles do not need to use internal combustion engines. Therefore, the motor of pure electric vehicles is equivalent to the engine of traditional vehicles, and the battery is equivalent to the original fuel tank. Electricity is a secondary energy source, which can be derived from wind, water, heat, solar and other energy sources. .
2) Features of pure electric vehicles
①No pollution, low noise
The exhaust gas produced by pure electric vehicles without internal combustion engines during operation does not produce exhaust gas pollution. It is very beneficial to environmental protection and air cleaning. It has the reputation of “zero pollution”; pure electric vehicles produce less noise than internal combustion engines. The noise is also lower than that of an internal combustion engine. However, the use of pure electric vehicles is not absolutely pollution-free. For example, lead-acid batteries are used as power sources. Lead is exposed to lead during manufacturing and use, and acid gas is generated during charging, which will cause certain pollution: the electricity used for battery charging is using coal. When making fuel, CO, SO2, dust, etc. are generated. With the development of technology, other clean energy sources can be used as power sources for electric vehicles, such as the development of hydropower, nuclear power, and solar charging.
②High energy efficiency and diversification
Research on pure electric vehicles has shown that their energy efficiency has surpassed that of gasoline-powered vehicles, especially in urban areas. Vehicles are often in the process of starting, driving at low speed and then braking and stopping. Pure electric vehicles are more suitable. Pure electric vehicles do not consume electricity when they stop. During the braking process, the motor can be automatically converted into a generator to realize the reuse of energy during braking and deceleration.
On the other hand, the application of pure electric vehicles can effectively reduce dependence on petroleum resources, and can use limited petroleum for more important aspects. The electricity to charge the battery can be converted from coal, natural gas, water power, nuclear power, solar power, wind power, tides and other energy sources. In addition, if you charge the battery at night, you can also avoid the peak power consumption, which is beneficial to balance the load of the grid and reduce costs.
③Simple structure, easy to use and maintain
Compared with internal combustion engine vehicles, pure electric vehicles have simpler structure, fewer operation and transmission parts, and less maintenance and repair work; when AC induction motors are used, the motors do not require maintenance; more importantly, pure electric vehicles are easy to operate.
④The cost of power battery is high, and the driving range is short
At present, pure electric vehicles are not as technically complete as internal combustion engine vehicles, especially the power source (battery) has a short life, high use cost, battery storage energy is small, the driving range after a single charge is not ideal, and the price of electric vehicles is more expensive. But from the perspective of development, with the breakthrough of pure electric vehicle technology, especially the increase in power battery capacity and cycle life, as well as the decrease in price, the promotion and use of pure electric vehicles will definitely get a big development.
3) Classification of pure electric vehicles
①Classification by purpose
According to different purposes, pure electric vehicles can be divided into the following categories
(1) Pure electric cars.
(2) Pure electric trucks.
(3) Pure electric passenger cars.
②Classification according to drive form
According to the different structure of the power drive control system, pure electric vehicles can be divided into the following categories:
(1) Pure electric vehicles driven by DC motors.
(2) Pure electric vehicles driven by AC motors.
(3) Pure electric vehicles driven by dual motors.
(4) Pure electric vehicles driven by dual-winding motors.
(5) Pure electric vehicles driven by in-wheel motors.
③Classified by the type of battery used
According to the different types of batteries used, pure electric vehicles can be divided into the following categories:
(1) Pure electric vehicles with lead-acid batteries.
(2) Ni-MH battery pure electric vehicles.
(3) Pure electric vehicles with lithium-ion batteries.
(4) Fuel cell pure electric vehicles.
