CN104596028B - The method whether frequency-changeable compressor of domestic multi-connection machine dallies is judged when heating - Google Patents

Abstract

The present invention judges the method whether frequency-changeable compressor of domestic multi-connection machine dallies when disclosing a kind of heat, and its step includes：Compressor is run (1) 8 minute with 40Hz frequencies in a heating mode；As 5 DEG C of 15 DEG C≤Tao ＜, judge whether while meet following two conditions, 1, compressor (1) electric current≤1.8A, 2, Tem Tai≤2 DEG C, if meeting above-mentioned two condition simultaneously, judge compressor (1) idle running；As 24 DEG C of 5 DEG C≤Tao ＜, judge whether while meet following two conditions, 1, compressor (1) electric current≤2A, 2, Tem Tai≤2 DEG C, if meeting above-mentioned two condition simultaneously, judge compressor (1) idle running.This method can accurately judge on the premise of low pressure switch is omitted, prevent compressor (1) idle running.

Description

The method of judging whether the household multi-connected inverter compressor is idling during heating

technical field

The invention relates to a household multi-connection air conditioner unit, in particular to a method for judging whether a household multi-connection frequency conversion compressor is idling during heating.

Background technique

The multi-connected air conditioner units in the prior art are referred to as multi-connected units for short, and the structure of the household-type multi-connected units is relatively simple, with only one outdoor unit and a small number of indoor units. The outdoor unit communicates with multiple indoor units connected in parallel.

The household multi-split unit includes a frequency conversion compressor, a four-way reversing valve, an outdoor heat exchanger (evaporator when heating), multiple electronic expansion valves and multiple indoor heat exchangers with the same number as the electronic expansion valves (Condenser when heating). The compressor outlet is connected to the first valve port of the four-way reversing valve, the second valve port of the four-way reversing valve is connected to one end of the outdoor heat exchanger, and the other end of the outdoor heat exchanger is connected to one end of all electronic expansion valves connected in parallel. The other end of each electronic expansion valve communicates with one end of an indoor heat exchanger, and the other ends of all indoor heat exchangers connected in parallel communicate with the third valve port of the four-way reversing valve, and the fourth valve port of the four-way reversing valve Connected to compressor inlet.

The compressor, four-way reversing valve, outdoor heat exchanger and electronic expansion valve belong to the outdoor unit, while the indoor heat exchanger belongs to the indoor unit. The middle part of the coil of the indoor heat exchanger is equipped with a first temperature sensor for measuring the temperature at this position, each indoor unit is also equipped with a second temperature sensor for measuring the indoor ambient temperature, and the outdoor unit is equipped with a third temperature sensor for measuring the outdoor ambient temperature. The above-mentioned temperature sensor and compressor are all electrically connected with the main controller of the air conditioner.

In the heating mode, the first valve port of the four-way reversing valve is connected to the third valve port, and the second valve port is connected to the fourth valve port, that is, the refrigerant flows along the compressor, indoor heat exchanger, electronic expansion valve, outdoor The route of heat exchanger and compressor circulates.

At present, the price war in the home multi-connection market has reached a fever pitch, and the cost control of various manufacturers has reached the point where every penny must be compared. Someone proposed to omit the low-pressure control switch located at the inlet of the compressor in the prior art to control costs, but the omission will lead to the following problem: once the electronic expansion valve of the air conditioner cannot be opened due to a fault, the compressor will not be able to inhale and cannot In the idling state of discharging the refrigerant, the continuous idling of the compressor will cause the internal temperature of the compressor to be too high, and the temperature sensor located outside the compressor cannot measure the internal temperature, so the long-term idling compressor is prone to explosion due to excessive temperature. Originally, the low-pressure pressure switch could detect the low-pressure failure of the compressor suction port and shut it down for protection, but if this part is omitted, the potential safety hazard of the compressor idling explosion cannot be ruled out.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method for judging whether a household multi-connected inverter compressor is idling or not during heating under the premise of omitting the low-pressure pressure switch, and preventing the compressor from idling.

The technical solution of the present invention is to provide a method for judging whether a household multi-connected frequency conversion compressor is idling during heating. The steps include: running the compressor at a frequency of 40 Hz for 8 minutes in the heating mode, and detecting the outdoor ambient temperature Tao , the indoor ambient temperature Tai and the temperature in the middle of the indoor heat exchanger coil Tem; when -15℃≤Tao<-5℃, judge whether the following two conditions are met at the same time, 1. Compressor current ≤1.8A, 2 , Tem-Tai≤2°C, if the above two conditions are met at the same time, it is judged that the compressor is idling; when -5°C≤Tao<24°C, it is judged whether the following two conditions are met at the same time, 1. The compressor current ≤2A, 2. Tem-Tai≤2°C, if the above two conditions are met at the same time, it is determined that the compressor is idling.

The principle of this judgment method is: once the compressor has been idling at a certain frequency such as 40Hz for a period of time such as 8 minutes, the refrigerant in the indoor heat exchanger must be sucked out, and the temperature in the middle of the coil of the indoor heat exchanger should be close to the indoor temperature. ambient temperature, and the compressor is not idling under normal circumstances, when there is gaseous refrigerant in the indoor heat exchanger, the temperature in the middle of the coil of the indoor heat exchanger must be much higher than the indoor ambient temperature; at the same time, once the compressor idling, The load of the compressor is small, and the current is naturally small, so once the compressor current is less than the judgment value and the difference between the temperature in the middle of the indoor heat exchanger coil and the indoor ambient temperature is less than the judgment value, it can be determined It is determined that the compressor is idling and the electronic expansion valve cannot be opened normally.

By adopting the above method, the method for judging whether the household multi-line frequency conversion compressor is idling when heating in the present invention has the following advantages compared with the prior art:

This control method can automatically detect when the air conditioner is in heating operation, and once the compressor is found to be idling, it will automatically stop for protection, avoiding the occurrence of compressor explosion caused by long-term idling of the compressor, and overcoming the technical problem that the low-pressure pressure switch cannot be omitted.

Description of drawings

Fig. 1 is a system schematic diagram of the method for judging whether a household multi-connected inverter compressor is idling during heating according to the present invention.

Shown in the figure is 1. compressor, 2. indoor heat exchanger, and 3. electronic expansion valve.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

As shown in FIG. 1 , the method of the present invention for judging whether a household multi-connected inverter compressor is idling during heating, the specific steps are as follows.

Run the compressor 1 at a frequency of 40Hz for 8 minutes in the heating mode, and detect the outdoor ambient temperature Tao, the indoor ambient temperature Tai, and the temperature in the middle of the coil of the indoor heat exchanger 2 with the corresponding electronic expansion valve 3 turned on. Tem. When -15℃≤Tao<-5℃, judge whether the following two conditions are met at the same time, 1. Compressor 1 current ≤1.8A, 2. Tem-Tai≤2℃, if the above two conditions are met at the same time, judge Compressor 1 is idling; when -5°C ≤ Tao < 24°C, judge whether the following two conditions are met at the same time, 1. Compressor 1 current ≤ 2A, 2. Tem-Tai ≤ 2°C, if the above two conditions are met at the same time , it is determined that the compressor 1 is idling. Once it is determined that the compressor 1 is idling, an alarm will be sent to the main controller of the air conditioner, and the compressor 1 will be shut down for protection. The method is automatically run at intervals such as 8 minutes, and the unit is automatically detected to prevent the compressor 1 from idling.

Claims (1)

1. A method for judging whether a household multi-connected inverter compressor is idling during heating, characterized in that: the steps include: running the compressor (1) at a frequency of 40 Hz for 8 minutes in the heating mode, and detecting the outdoor ambient temperature Tao , the indoor ambient temperature Tai and the coil middle temperature Tem of the indoor heat exchanger (2) that is turned on; when -15°C≤Tao<-5°C, judge whether the following two conditions are met at the same time, 1. Compressor (1) Current ≤ 1.8A, 2, Tem-Tai ≤ 2°C, if the above two conditions are met at the same time, it is judged that the compressor (1) is idling; when -5°C ≤ Tao < 24°C, it is judged whether the following two conditions are met at the same time , 1. Compressor (1) current ≤ 2A, 2. Tem-Tai ≤ 2 ° C, if the above two conditions are met at the same time, it is determined that the compressor (1) is idling.