Refrigerant flow control method and device for fixed-frequency ice-accumulation air-conditioning unit

Abstract

The invention discloses a method for controlling the flow rate of freezing medium in a fixed-frequency ice accumulating air-conditioning unit and a device thereof. The method comprises: at least more than one temperature sensors are distributed in an ice accumulating groove along the horizontal direction and along the depth direction, and at least one in heat exchange pipes of a heat exchanger in the ice accumulating groove is provided with the temperature sensors; the temperature value in the ice accumulating groove is acquired within the preset time, the average water temperature is calculated, and the temperature at an outlet of the heat exchanger and the average temperature at the middle part of a heat exchange pipe are acquired; when the average water temperature is judged to be within the preset range of regulating the opening of a throttle valve, the difference value between the temperature at the outlet of the heat exchanger and the average temperature at the middle part of the heat exchange pipe is judged, and the opening of the throttle valve is regulated according to the preset method. The invention can accurately measure the temperature, avoid liquid accumulating in an evaporator, enlarge the heat exchange area and improve the cold accumulation COP.

Description

technical field [0001] The invention relates to refrigeration control of an air-conditioning unit, in particular to a refrigerant flow control method and device for a fixed-frequency ice-storage air-conditioning unit. Background technique [0002] In the refrigeration process, for the ice storage refrigeration unit whose compressor frequency is not adjustable, the entire ice storage process is an unsteady heat transfer process, and the heat transfer capacity changes from large to small, requiring the refrigerant flow rate of the refrigeration system to follow suit. Variety. Generally, the opening of the throttle valve is controlled by detecting the superheat degree of the refrigerant at the outlet of the evaporator, so as to realize the control of the refrigerant flow. This method has the following disadvantages: when storing cold in the sensible heat section, due to the high water temperature, large heat transfer, and large suction superheat, the expansion valve will be op...

AI Technical Summary

Problems solved by technology

[0003] In view of this, the present invention is to provide a refrigerant flow control method and device for a fixed-frequency ice storage air-conditioning unit to solve the above-mentioned problems caused by the misjudgment of the temperature sensor when the refrigerant reaches a saturated state. The problem of liquid accumulation, reduction of evaporation heat transfer area, increase of time required for cold storage, and increase of required power consumption

Images