Control method of multi-split air conditioning system

Abstract

The invention discloses a control method of a multi-split air conditioning system. The multi-split air conditioning system comprises an outdoor unit and a plurality of indoor units, wherein the outdoor unit comprises a compressor, an outdoor heat exchanger and a main throttling element. The control method of the multi-split air conditioning system comprises the following steps that a current operation mode of the multi-split air conditioning system is acquired, when the current operation mode of the multi-split air conditioning system is a pure refrigeration mode or a hybrid operation mode, anoutdoor ambient temperature T1 is obtained, wherein the number of the indoor units in a refrigeration state is M; when the outdoor ambient temperature T1 is less than a first preset temperature, an evaporation temperature T2 of the M indoor units in the refrigeration state is obtained; and when the evaporation temperature T2 of N indoor units in the M indoor units in the refrigeration state is less than a second preset temperature, the N indoor units are controlled to generate heat to enable the N indoor units to enter in an anti-freezing mode, wherein N is less than or equal to M. Accordingto the control method of the multi-split air conditioning system, the indoor units entering in the anti-freezing mode can quickly exit the anti-freezing mode.

Description

technical field [0001] The invention relates to the technical field of refrigeration and heating, in particular to a control method for a multi-connected system. Background technique [0002] At present, the insulation performance of buildings is getting better and better. Even if the outdoor ambient temperature is below 0°C, there is a demand for indoor cooling in places with large heat sources such as computer rooms and kitchens. The air conditioning system may operate in pure cooling mode or mixed mode. In this case, it is easy to cause the evaporation temperature of the indoor unit to be low, and the surface of the evaporator is frosted and icy, so that the air conditioning system enters the anti-freezing protection state (or called anti-freezing mode). [0003] In the related art, in order to make the indoor unit exit the antifreeze protection state, the indoor unit is shut down, that is, the throttling element of the indoor unit such as the electronic expansion valve i...

AI Technical Summary

Problems solved by technology

However, this way of using convective heat exchange makes the indoor unit exit the anti-freezing state slowly, especially when the surface of the evaporator is severely frozen, the indoor unit cannot run for a long time, and the ice on the surface of the evaporator may not completely melt. Thus affecting the reliability and comfort of the air conditioning system

[0004] In addition, it is also possible to increase the speed of the indoor unit exiting the anti-freezing state by adding an auxiliary heater. However, this method requires changing the structure of the indoor unit and increases additional power consumption.

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