Appointed subharmonic compensation APF (active power filter) and harmonic detection and control method thereof

Abstract

The invention discloses an appointed subharmonic compensation APF (active power filter) and a harmonic detection and control method thereof. The APF comprises a signal sampling module (1), a human-computer interaction interface (2), an appointed subharmonic current detection module (3), a current tracking control module (4) and a power circuit module (5), wherein the signal sampling module transmits a collected signal to the appointed subharmonic current detection module; the human-computer interaction interface is connected with the appointed subharmonic current detection module; the appointed subharmonic current detection module is connected with the power circuit module via the current tracking control module. According to the APF, one or multiple times of harmonic of the harmonic current generated by load in a power grid can be appointed to carry out harmonic separation detection and compensation by the human-computer interaction interface, and various different working condition requirements can be satisfied in a flexible working mode. With the method, the stability and the reliability of harmonic detection and compensation current are enhanced so as to enhance the system stability and improve the system reliability.

Description

technical field [0001] The invention relates to an APF and a harmonic detection and compensation current tracking control method thereof, in particular to a specified harmonic compensation APF and a harmonic detection and control method thereof, which belong to the field of harmonic detection and harmonic control. Background technique [0002] With the rapid development of the economy, power electronic conversion devices have been widely used in the industrial field, making the harmonic pollution of the power grid more and more serious. The active power filter (APF) is recognized as a A new type of power electronic device that dynamically suppresses harmonic pollution of the power grid, which can compensate for harmonics that vary in size and frequency and reactive power that varies. According to the way the active power filter is connected to the grid, its basic topology can be divided into two types: parallel type and series type. The parallel type and series type active p...

AI Technical Summary

Problems solved by technology

[0004] 1. Harmonic detection based on instantaneous reactive power theory can separate active current and reactive current in real time, and the detection is not affected by grid voltage distortion. However, this method requires a large number of coordinate transformations and requires the design of high-performance low-pass filters, so The system has contradictions in accuracy and stability, and this method cannot be applied to single-phase systems;

[0005] 2. Based on Fourier transform fast FFT detection, a certain harmonic can be selectively eliminated. The basis of this method is Fourier transform, which requires the collected data waveform to have the characteristics of periodic transformation, and there are problems such as leakage and aliasing. , and the Fourier transform and its inverse transform require a lot of calculations, so the time delay is large, and the real-time performance of harmonic detection is poor;

These disadvantages limit the application of sliding mode variable structure control.

Images