What are the main driving forces of new energy vehicles?

The driving mode of new energy vehicles in Pacific Auto Network refers to vehicles that do not use conventional oil as driving power, or use both oil and fuel. It can be divided into pure electric fuel cells, hydrogen-powered vehicles and other new energy types.

Traditional automobile-driven vehicles rely on internal combustion engines to do work, change the transmission ratio and rotation direction of output power through a transmission, and then realize vehicle running through transmission shafts and wheels. The electric drive system of pure electric vehicle replaces the internal combustion engine and transmission of traditional automobile, and the vehicle is driven by power battery, inverter and motor transmission unit.

1) Basic drive components The main components of the pure electric vehicle drive system include power battery, inverter and speed change unit with motor.

Figure 3-2-3 is a schematic diagram of the drive system of a typical pure electric vehicle. In the application of new energy vehicles, the circuit unit between power battery pack and inverter is generally called BDU (battery connection unit).

2) The driving power source of a pure electric vehicle in the basic driving process is the power battery, but unlike traditional vehicles, the electric energy from the power battery is not always in the output state. In pure electric vehicles, there is also a mechanism to recover the useless energy when braking the vehicle and recycle it into the power battery.

There are two main paths for energy flow in the driving process of pure electric vehicles:

(1) When the vehicle is running, the energy from the power battery passes through the BDU and inverter, and then enters the motor speed change unit to drive the vehicle.

(2) When the braking energy is recovered for braking or vehicle deceleration, the motor in the transmission unit will become a generator, and the energy will return to the power battery through the inverter and BDU to charge the battery.

3) The main control module Pure electric vehicle can respond quickly and drive the vehicle smoothly under different road conditions, and meet the needs of drivers. Not only do it rely on the above power components, but the whole drive system also needs a set of perfect control modules. Namely vehicle controller (VCU), motor controller (MCU) and battery management system (BMS). These three controllers are the core technologies of pure electric vehicles, which have an important impact on the power, economy, reliability and safety of the whole vehicle.

(Photo/Text/Photo: Pacific Auto Network Q&A called Beast)