What is the temperature adjustment principle of variable frequency central air conditioning?

The principle of AC variable frequency central air conditioning is to convert power frequency AC into DC power supply and send it to the power supply module. At the same time, the module is controlled by the control signal sent by the microprocessor, and outputs an AC power supply with adjustable frequency, so that the rotation speed of the compressor motor changes correspondingly with the change of the power supply frequency, thereby controlling the displacement of the compressor and adjusting the cooling capacity or heating capacity. As shown in Figure 2-3, it is the working principle block diagram of AC inverter of central air conditioner.

Figure 2-3 working principle block diagram of AC inverter of central air conditioner

1. Room temperature detection and frequency control II. Power frequency power supply 3. Power supply 4. Inverter 5. 6.PWM/PAM control of compressor (AC motor).

The central air conditioner with frequency converter can continuously adjust the rotating speed of the compressor motor and change the rotating speed of the compressor according to the indoor air conditioning load. When the indoor temperature needs rapid cooling (or rapid heating), the room temperature detection signal will be sent to PWM (pulse width modulation, rotation speed can not exceed 7000r/min) or PAM (pulse amplitude modulation, rotation speed can not exceed 10500r/min) controller, and then added to the frequency converter and compressor. When the set temperature is reached, the compressor will immediately run at a low speed and keep the room temperature basically unchanged.