Voltage short interruption reply method and device of single-phase AC power supply

Abstract

The invention discloses a voltage short interruption reply method and device of a single-phase AC power supply provided for an air-conditioning system. The single-phase AC power supply goes through rectification of a rectifier circuit and then is input to a power factor correction (PFC) circuit. The method comprises the following steps: detecting a voltage input to the PFC circuit to obtain an input voltage instantaneous value, and judging whether a voltage short interruption occurs in the single-phase AC power supply according to the input voltage instantaneous value; if the voltage short-time interruption occurs according to the judgment, controlling a power switch tube in the PFC circuit to be turned off, and reducing an operation frequency of a compressor; judging whether a voltage of the single-phase AC power supply returns to normal; and, if the voltage returns to normal according to the judgment, improving the operation frequency of the compressor until a given frequency is reached, and, when the input voltage instantaneous value is less than or equal to an output end DC bus voltage of the PFC circuit, controlling the power switch tube to be turned on. So an input current when the voltage recovers is reduced, working time when the voltage interruption occurs is prolonged, and then the anti-interference ability of the system to the voltage short interruption is improved.

Description

technical field [0001] The invention relates to the technical field of air conditioning, in particular to a method for responding to a short-time voltage interruption of a single-phase AC power supply to an air-conditioning system and a device for responding to a short-time voltage interruption of a single-phase AC power supply to an air-conditioning system. Background technique [0002] In a single-phase AC power input system such as a household air conditioner, the single-phase AC power from the grid usually passes through an uncontrollable full-bridge rectifier circuit first, then passes through a power factor correction circuit, then outputs DC and connects it to a large-capacity electrolytic capacitor, and finally provides it to load. Among them, the power factor correction circuit generally adopts a typical Boost power factor correction circuit, and the load includes an internal switching power supply, a compressor and a fan. [0003] In the GB-T17626.11-2008 standard...

AI Technical Summary

Problems solved by technology

When the voltage recovers, first of all, due to the PFC circuit adjustment lag, the current surge of the power switch tube of the PFC circuit may cause a current overcurrent protection; secondly, the input voltage may be higher than the DC bus voltage at the recovery time, causing electrolytic capacitors to charge The current is very large, plus the load current, it is easy to have an overcurrent fault

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