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

Abstract

The invention discloses a low-temperature refrigeration control device of a single-phase motor in an air conditioning unit, which comprises a motor control module, a first pressure switch and a second pressure switch, wherein the closed pressure valve value of the first pressure switch is higher than that of the second pressure switch; an N-wire interface of the motor control module is connected with zero line and the zero line interface of the motor driving an outdoor blower; an L-wire interface is connected with a fire line; an HF interface and an LF interface are respectively connected with a high speed / low speed running control port of the motor; a PS1 interface and a PS2 interface are respectively connected with one ends of the first pressure switch and the second pressure switch, and the other ends of the first pressure switch and the second pressure switch are connected in parallel and connected with the COM interface of the motor control module; and the low-temperature refrigeration control device controls the rotating speed of the motor by collecting the air pressure value at the outlet of a condenser, and leads the pressure of condenser to fluctuate in a normal range, thus avoiding dangerous conditions of incomplete evaporation of the system, frosting or even frost cracking of an evaporator and the like caused by over-low condensing pressure due to low temperature, and improving the running conditions of low-temperature refrigeration of the air conditioning unit.

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]...

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

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