Power converter for inverter air conditioner and control method of power converter

Abstract

The invention provides a power converter for an inverter air conditioner. The power converter comprises a rectification circuit, an AC current collection circuit, an AC voltage collection circuit, a DC voltage collection circuit and a digital signal processor; the rectification circuit is controlled to carry out rectification on a three-phase AC power supply; the AC current collection circuit collects an input current signal of the three-phase AC power supply; the AC voltage collection circuit collects an input voltage signal of the three-phase AC power supply; the DC voltage collection circuit collects an output voltage signal after rectification by the rectification circuit; and the digital signal processor calculates an input current value and an input voltage value of the three-phase AC power supply and an output voltage value of the rectification circuit, carries out real-time feedback calculation to provide a control signal for the rectification circuit according to a feedback calculation result, so that the output voltage of the rectification circuit is stabled in a reference voltage value and the input current phase of the three-phase AC power supply follows the input voltage phase of the three-phase AC power supply. According to schemes of the invention, the power factor is high, the content of harmonic waves is low, and the complex degree and sampling errors of circuits are reduced.

Description

technical field [0001] The invention relates to the control of an inverter air conditioner, in particular to a power conversion device for an inverter air conditioner and a control method thereof. Background technique [0002] In the inverter air conditioner, the AC-DC power supply is generally converted, and the drive signal is provided to the inverter compressor through the rectification and inversion. During the power conversion process, there will be a phase difference between the current and the voltage, which will cause the power quality to decline, and will generate Exchange power loss. [0003] To solve this problem, a power factor correction (Power Factor Correction, PFC for short) technology appears in the prior art. PFC technology is generally divided into passive PFC and active PFC. Among them, the current frequency conversion air conditioner manufacturers generally use passive PFC, and its main technical means is to connect and connect in series with specific ...

AI Technical Summary

Problems solved by technology

The rectified output bus voltage cannot be raised and stabilized, and varies with the cooling and heating modes of the air conditioner, and the load is nonlinear and discrete and fluctuates greatly

[0005] The power factor of active PFC can reach 0.999 or higher, THDi (Total Harmonic Current Distortion, total harmonic current effective value) can be less than 5%, each harmonic can meet the national standard requirements, and expand the torque range of the compressor, that is Increase the load capacity of the air conditioner, but due to the difficulty of active PFC technology and the complicated signal processing process and high cost, few air conditioner manufacturers currently use this technology

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