Oil return control method and device for multi-split system, oil return control equipment and air conditioner

Abstract

The invention relates to an oil return control method and device for a multi-split system, oil return control equipment and an air conditioner. The oil return control method comprises the steps that the ratio of an indoor unit and an outdoor unit of a multi-split system and system real-time operation parameters are obtained; the system real-time operation parameters comprise the outdoor environment temperature; a system to-be-executed oil return mode is determined according to the outdoor environment temperature; the system to-be-executed oil return mode comprises a high-temperature refrigeration oil return mode and a standard oil return mode; a preset ratio interval where the ratio of the indoor unit and the outdoor unit is located is determined; the preset ratio interval comprises two ormore preset ratio subintervals; and the oil return time interval and the oil return frequency are determined according to the system to-be-executed oil return mode and the preset ratio interval. By adopting the oil return control method and device for the multi-split system, or the oil return control equipment or the air conditioner, the oil return time interval and the oil return frequency can be determined by being combined with the ratio of the indoor unit and the outdoor unit according to the different oil return modes, and the accuracy of oil returning control is greatly improved.

Description

technical field [0001] The invention relates to the technical field of multi-line oil return control, in particular to a multi-line system oil return control method, device, oil return control equipment and air conditioner. Background technique [0002] When the multi-line system is refrigerated at high temperature, due to the high system pressure and high exhaust temperature of the compressor, most of the units will run at low frequency for a long time due to the protection function. At this time, the lubricating oil in the pipeline and internal machine test will accumulate more and more . In addition, the oil return mode of the multi-line system is mostly in the cooling mode, and the compressor runs at the highest frequency to bring the refrigerant in the pipeline back to the compressor side through the high-speed flow of the refrigerant. However, the high pressure and high temperature in the pipe accompanied by high-temperature refrigeration will mostly cause the unit to...

AI Technical Summary

Problems solved by technology

However, the high pressure and high temperature in the pipe accompanied by high-temperature refrigeration will mostly cause the unit to be forced to reduce the frequency to achieve self-protection. If the setting of the frequency reduction range is unreasonable, if the setting reduction range is too large, the oil carrying capacity of the compressor at low frequency will be weak, and it will not be effective. Oil return, in the oil return mode for a long time, affects the indoor cooling effect. If the setting is too small, the high pressure and high temperature in the system cannot be effectively reduced, and the unit may be forced to shut down or reduce frequency again, resulting in the unit being shut down or reducing frequency for a long time , unable to achieve efficient oil return

[0003] In the prior art, high-temperature refrigeration is treated differently, and most of them use the exhaust temperature and high-pressure value as the judgment value. If the judgment value is exceeded, a simple frequency reduction is performed, but this kind of frequency reduction is often large in magnitude and low in accuracy; Step down frequency, but this kind of frequency reduction is to explore the oil return adaptation frequency of the unit in a small range, and then reduce the frequency after protection, repeating, most of the units are in the protection frequency reduction, this kind of frequency reduction mode needs repeated reduction Frequency, cumbersome operation, affect the cooling effect, reduce the user's product experience

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