Control Method and Device for Controlling Air Conditioning Unit, and Air Conditioning Unit

A control device for an air conditioning unit, comprising:

• an acquisition module for obtaining a return air temperature, a condensation temperature, an evaporation temperature, compressor parameters, and fan parameters of the air conditioning unit, wherein the air conditioning unit comprises a compressor and a fan;
• a first determination module for determining a preset evaporation temperature according to the return air temperature, the condensation temperature, the evaporation temperature, the compressor parameters, the fan parameters, a compressor power curve, and a fan power curve, wherein a sum of a compressor power and a fan power is minimized at the preset evaporation temperature;
• a second determination module for determining a preset compressor frequency and a preset fan frequency according to the compressor power curve and the fan power curve;
• and
• a control module for controlling the compressor according to the preset compressor frequency, and controlling the fan according to the preset fan frequency.

An air conditioning unit, comprising:

• a compressor and a fan;
• a temperature sensor configured to detect a return air temperature of the air conditioning unit;
• a first pressure sensor configured to detect a first pressure for determining a condensation temperature of the air conditioning unit;
• a second pressure sensor configured to detect a second pressure for determining an evaporation temperature of the air conditioning unit;
• and
• a controller configured to
• obtain the return air temperature, the condensation temperature, the evaporation temperature, compressor parameters, and fan parameters,
• determine a preset evaporation temperature according to the return air temperature, the condensation temperature, the evaporation temperature, the compressor parameters, the fan parameters, a compressor power curve, and a fan power curve, wherein a sum of a compressor power and a fan power is minimized at the preset evaporation temperature,
• determine a preset compressor frequency and a preset fan frequency corresponding to the preset evaporation temperature according to the compressor power curve and the fan power curve, and
• control the compressor according to the preset compressor frequency, and control the fan according to the preset fan frequency.