Low-temperature refrigerating control device of air conditioning unit single-phase motor

Abstract

The invention discloses a low-temperature refrigerating control device of an air conditioning unit single-phase motor. The low-temperature refrigerating control device comprises a motor control module, a first pressure switch and a second pressure switch. The closing pressure threshold value of the first pressure switch is higher than the closing pressure threshold value of the second pressure switch. An N line connector of the motor control module is connected with a zero line and is connected with a zero line connector of a motor driving an outdoor draught fan; an L line connector is connected with a firing line; an HF connector and an LF connector are connected with a high speed / low speed running control port of the motor; and a PS1 connector and a PS2 connector are connected with one end of the first pressure switch and one end of the second pressure switch correspondingly, and the other end of the first pressure switch and the other end of the second pressure switch are connectedin parallel and are connected with a COM connector of the motor control module. The rotating speed of the motor is controlled by collecting the air pressure value of an outlet of a condenser so that the pressure of the condenser can fluctuate in a normal range, and therefore dangerous conditions that system evaporation is incomplete, an evaporator is frosted or even subjected to frost crack due toextremely low condensation pressure caused by the low temperature are avoided, and the low-temperature refrigerating running condition of an air conditioning unit is improved.

Description

technical field [0001] The invention relates to the technical field of control devices for motors of air-conditioning units, in particular to a low-temperature refrigeration control device for single-phase motors of air-conditioning units. Background technique [0002] Existing air conditioners include a refrigeration circuit and an electrical control system, and the refrigeration circuit is composed of a compressor, a condenser, capillary components and an evaporator. The electronic control system includes components such as circuit control board, thermistor, control valve and fan motor. During cooling operation, the air conditioner transfers heat from the indoor to the outdoor through the work of the compressor according to the refrigeration principle. Generally, when the cooling is running, the indoor temperature will be higher than the outdoor temperature, and the condensing capacity of the refrigeration device will increase as the outdoor temperature drops. [0003] T...

AI Technical Summary

Problems solved by technology

For traditional household air conditioners, cooling operation is performed when the outdoor ambient temperature is lower than 0°C. Since the outdoor air temperature is very low, the condensation temperature on the outdoor side is very low, and the temperature of the refrigerant at the outlet of the condenser can reach below 10°C. When the condensing pressure fluctuates greatly, resulting in low condensing pressure, after the refrigerant passes through the capillary part, its evaporation temperature is often lower than -5 ° C, and then through the capillary throttling, the refrigerant enters the indoor evaporator, which is easy to cause frost and ice. Affect the circulating air volume on the indoor side and affect the cooling effect

Images