Three-phase synchronous rectification circuit and control method thereof

Abstract

The invention relates to a three-phase synchronous rectification circuit, which is applied to a four-quadrant frequency converter and is provided with a direct current end and an alternating current end. The three-phase synchronous rectification circuit comprises at least three double-tube packaged insulated gate bipolar transistors and a diode, wherein the diode is connected in reverse parallel with each insulated gate bipolar transistor; the at least three double-tube packaged insulated gate bipolar transistors are connected in parallel to form a three-phase bridge circuit; a controller is also connected between the three-phase synchronous rectification circuit and a power system and is used for controlling the conduction of each insulated gate bipolar transistor according to a phase position of a three-phase alternating voltage input by the power system; when the input voltage in the four-quadrant frequency converter is greater than the voltage of a direct current bus, the three-phase synchronous rectification circuit is in a rectification state; and when the voltage of the direct current bus in the four-quadrant frequency converter is greater than the input voltage, the three-phase synchronous rectification circuit is in an energy feedback state. As the rectification circuit is controlled by the phase position, the three-phase synchronous rectification circuit has the advantages of low cost, low switching loss and anti-interference capacity. Besides, the invention also provides a control method for the synchronous rectification circuit.

Description

technical field [0001] The invention relates to the field of electronic power, in particular to a three-phase synchronous rectification circuit applied to a four-quadrant frequency converter and a control method for the synchronous rectification circuit. Background technique [0002] As the country's energy-saving and emission-reduction policies become clearer and deeper, as a large power-consuming device, the proportion of motors using frequency converters for speed regulation is also increasing. Inverter is a power control device that converts power frequency power to another frequency by using the on-off function of power semiconductor devices. Its most important feature is its high-efficiency drive performance and good control characteristics. Simply put, the frequency converter first converts the electric energy of the AC power supply into DC power, and then changes the DC power into AC power with variable frequency to drive the load, such as changing the motor speed by...

AI Technical Summary

Problems solved by technology

Although it can realize the perfect energy feedback function, it has the disadvantages of high system cost and large interference. At present, it is only used in high-end industries that require high performance but not too much cost. However, it is still lacking in the general-purpose inverter industry that requires low cost. Competitiveness

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