New Energy Vehicle Air Conditioning Compressor Revealed

With the rise of new energy vehicles, automotive air-conditioning compressors have followed suit with dramatic changes: the front-end drive wheel has been eliminated, and a drive motor and separate control module have been added.

The new drive motor is a three-phase permanent magnet synchronous motor, which has the advantages of small size, light weight and high efficiency.

Since DC batteries are used in electric vehicles, the DC power must be converted to AC power with the help of a control module (inverter) if the drive motor is to work normally and stably. That is, through the control module in the voltage control device, according to a certain law in turn plus the duty cycle pulse modulation control voltage.

When the DC high-voltage current through the inverter, the output side of the formation of three-phase sinusoidal AC current, so that it ensures the smooth operation of three-phase permanent magnet synchronous motor at the same time, can produce enough torque to drive the compressor operation.

Scroll electric compressor is widely used in new energy electric vehicles due to its many advantages such as low vibration, low noise, long service life, light weight, high speed, high efficiency, small external dimensions and so on.

The core component of the scroll compressor includes two scroll discs that engage with each other:

A fixed scroll disc (fixed in the frame); a dynamic scroll disc (driven directly by the motor, around the fixed scroll disc to do a small radius of rotation of the rotary motion). The discs are assembled together in such a way that they are staggered by 180°, i.e. the phase angles are 180° apart, because they are of the same linear shape.

When the drive motor rotates to drive the dynamic scroll disc, the refrigeration gas is sucked into the peripheral part of the fixed scroll disc through the cartridge, and with the rotation of the drive shaft, the dynamic scroll disc operates according to the trajectory in the fixed scroll disc. So that the dynamic and fixed scroll disc formed between the volume from the outside to the inside of the six cavities gradually reduced, the refrigeration gas in the dynamic and fixed scroll disc is composed of six crescent-shaped compression chamber is gradually compressed, and finally from the fixed scroll disc through the hole in the centre of the valve will be compressed refrigeration gas continuously discharged.

Because of the working chamber are from the outside to the inside gradually become smaller and in different compression conditions, so as to ensure that the scroll compressor can continuously suction, compression and exhaust. And the dynamic scroll disc can be as high as 9000 ~ 13000r/min rotation, the output of the large displacement is sufficient to ensure that the vehicle air-conditioning refrigeration requirements.

In addition, the scroll compressor does not need an inlet valve, only the exhaust valve, which can simplify the structure of the compressor, eliminate the pressure loss of the open valve at the same time, but also improve the compression efficiency.