Phase sequence detection circuit, control board and phase sequence protection device

Abstract

The invention discloses a phase sequence detection circuit for a three-phase power supply, wherein the phase sequence detection circuit comprises a power supply signal collecting module (410) and a judging module (420). The judging module (420) comprises comparing units (421a-421c) and time delay units (422a-422c), and is configured as follows: a collected result signal of each phase is respectively compared with a desired voltage waveform signal by the comparing units (421a-421c); a compared result signal of each phase is output, respectively; the compared result signals are respectively received by the time delay units (422a-422c); the compared result signal of each phase is repeatedly detected in a predetermined delay time section, respectively; and subsequently, a phase sequence detection result signal of each phase is respectively output. The phase sequence detection circuit of the invention has the advantages of high timing precision, wide range of application, lighter load for both a CPU (Central Processing Unit) and software, and property for a non-real-time operating system.

Description

technical field [0001] The present invention relates to phase sequence protection of equipment using three-phase power supply, and more particularly relates to a phase sequence detection circuit integrated on a control board. Background technique [0002] Phase sequence protection is mainly used to prevent phase loss and reverse phase caused by three-phase power wiring problems, so as to avoid functional and safety damage to equipment using three-phase power supply. [0003] At present, a dedicated external phase sequence protector is generally used, or a control board integrated with a phase sequence detection circuit is used to realize the phase sequence protection function through hardware or a combination of software and hardware. Among them, the phase sequence protector is an outsourced special device, which generally can only realize the functions provided by the supplier in advance, with high price, less functions and less freedom. The phase sequence detection circui...

AI Technical Summary

Problems solved by technology

[0018] In order to solve the problems of low timing accuracy, narrow application range, heavy load on CPU and software, and inability to be used in non-real-time operating systems in the prior art, the present invention provides a three-phase power supply phase A sequence detection circuit, comprising: a power signal acquisition module (410), which utilizes a virtual central line (N') to respectively acquire the voltage signals of each phase of the three-phase power supply, and output the acquisition result signals of each phase respectively; and a judgment module ( 420), receiving the collection result signal, and judging based on the collection result signal whether the three-phase power supply is out of phase and whether it is in reverse phase, and outputting the phase sequence detection result signals of each phase respectively

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