Unit oil return control method, system and multi-connection

Abstract

The invention relates to a unit oil return control method and system as well as a multi-connected air conditioning unit. The control method comprises the following steps that outdoor air temperature parameters in a preset unit working time period in a period of time in the future are acquired; the total oil return time required by a unit in the time period is obtained according to the acquired outdoor air temperature parameters; and an oil return mode is started at least the total oil return time earlier before the preset unit working time period begins. According to the control method, according to the weather parameters in a period of time in the future, the total oil return time required in the preset unit working time period is quantified and calculated so that the advanced oil returntime can be accurately determined, then the oil return mode can be started in advance, it is ensured that the unit can not be lack of oil in the preset oil return forbidding time period, then oil return does not need to be performed or the oil return frequency can be reduced in the preset unit working time period, and uncomfortable feeling caused by the fact that users are frequently disturbed bythe oil return noise or the oil return frequency is overhigh during use by the users can be avoided.

Description

technical field [0001] The invention relates to the technical field of unit control, in particular to a unit oil return control method, system and multiple units. Background technique [0002] The oil return of the unit is to ensure the normal operation and heat dissipation of the compressor. Poor oil return will cause the unit (compressor) to wear or even burn out. When the unit is in the oil return mode, the compressor runs at the highest frequency or close to the highest frequency, and the noise caused by the high-speed flow of the refrigerant is relatively large. Moreover, when most of the multi-connected units are returning oil, no matter whether the internal units are turned on or not, the electronic expansion valves of all the internal units must be opened to flush the refrigerant stored inside them back to the external unit side, so that the internal units that are shut down The machine will also produce noise, which will affect the user's rest or work, and the fluc...

AI Technical Summary

Problems solved by technology

Moreover, when most of the multi-connected units are returning oil, no matter whether the internal units are turned on or not, the electronic expansion valves of all the internal units must be opened to flush the refrigerant stored inside them back to the external unit side, so that the internal units that are shut down The machine will also produce noise, which will affect the user's rest or work, and the fluctuation of the unit's capacity during oil return will also bring discomfort to the user

[0003] Most of the current multi-line equipment adopts timing oil return control, such as forced oil return once every 2 hours. This oil return procedure is simple and reliable. It is not accurate enough to meet the working needs of the compressor well, and it is also difficult to adapt to the user's increasing requirements for comfort

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