Serial hybrid active filter including harmonic absorber

Abstract

The invention discloses a serial hybrid active filter including a harmonic absorber. The serial hybrid active filter comprises an active filter unit and a passive filter unit, wherein the active filter unit comprises a transformer, an inverter and a detection control unit; a primary side AX of the transformer is connected in series to a power grid; a secondary side of the transformer is connected with the inverter; the detection control unit is used for detecting a voltage or current signal of the primary side, and driving and controlling the on / off of a switch tube of the inverter to generate a voltage or current to be applied to the secondary side of the transformer, so that the primary side AX of the transformer presents low impedance to fundamental waves and presents high impedance to harmonic waves; and the passive filter unit comprises LC series-parallel branches which are connected in parallel to two ends of a harmonic source load. During working, the active filter unit presents low impedance to the fundamental waves and presents high impedance to high-order harmonic waves. A serial part of the passive filter unit generates series resonance at m-order harmonic frequency, and absorbs m-order harmonic current, so that the harmonic waves flow through the passive filter unit instead of flowing into the power grid, and a function of filtering the harmonic waves is realized.

Description

technical field [0001] The invention belongs to the technical field of power filters, and in particular relates to a series hybrid active filter with a harmonic absorber. Background technique [0002] With the rapid development of power electronic device manufacturing technology and converter technology, power electronic technology has been widely used in industrial manufacturing, household appliances, large shopping malls and office buildings, medical institutions, smart grids and other occasions. Since the power electronic device is a nonlinear load, its large-scale application will inevitably bring problems of harmonic interference and low power factor. The problem of harmonic interference can be solved by filtering. Passive filters are currently the most widely used filters. method, but to achieve a good filtering effect, the number of filtering branches of the passive filter must be increased, and the volume of the passive filter is increased. At the same time, the equi...

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Problems solved by technology

[0010] Aiming at the defects of the prior art, the object of the present invention is to provide a series hybrid filter with a harmonic absorber, aiming to solve the problem of the large number of passive filter units and the complicated parameter design of the common series hybrid active filter. problem, and can achieve a good filtering effect at the same time

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