Three-phase alternating current phase sequence detection apparatus and method

Abstract

The invention discloses a three-phase alternating current phase sequence detecting device and a method thereof. The detecting device comprises a three-phase alternating current sampling module, a coordinate system transformation module, an angular frequency signal acquirement module and a phase sequence direction judgment module. The detecting device includes the following detecting method: A. the three-phase alternating current sampling module samples the instantaneous values of current three-phase alternating current to obtain a sampling instantaneous value; B. the coordinate system transformation module converts the sampling instantaneous value into a two-phase synchronous rotating coordinate system from a three-phase static coordinate system, and q axis component xq can be worked out; C. the angular frequency signal acquirement module receives xq and obtains an error signal; the error signal can be adjusted to change the value of the xq; the acquired value of the angular frequency Omega 0 can be output to a feedback channel module thereof and the phase sequence direction judgment module; the feedback channel module outputs Omega 0 to the coordinate system transformation module; D. the phase sequence direction judgment module distinguishes the mark of Omega 0 and determines the phase sequence direction. The device provided by the invention can detect the real-time condition of the phase sequence. The device provided by the invention is simple and practical and has excellent capacity of resisting disturbance.

Description

technical field [0001] The invention belongs to the field of three-phase alternating current, and in particular relates to a three-phase alternating current phase sequence detection device and a detection method thereof. Background technique [0002] In many three-phase equipment application fields, the phase sequence of three-phase AC has an important impact on the normal operation of electrical equipment, and in many cases, the opposite power supply phase sequence is not allowed. Take three-phase AC traction power transmission equipment as an example, such as elevators and lathes, etc. AC motor traction equipment controls the running direction of the transmission equipment by changing the phase sequence of the motor supply voltage. In normal operation, once the phase sequence is reversed, The direction of operation will also change, so it is necessary to introduce phase sequence detection in the control of transmission equipment, otherwise it will cause equipment failure o...

AI Technical Summary

Problems solved by technology

The problem with this phase sequence detection circuit is that when the three-phase input is severely distorted, the signals input to the counter pulse input terminal and the reset terminal no longer differ by 120°, which may cause misjudgment or detection lag

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