Novel non-resonance passive zero-sequence filter

Abstract

The invention discloses a novel non-resonance passive zero-sequence filter, and relates to a harmonic suppression device for neutral lines of a low-voltage power distribution network. The novel non-resonance passive zero-sequence filter comprises an iron core and a coil. The novel non-resonance passive zero-sequence filter has the advantages that numbers of turns of six windings of the coil are equal, the six windings of the coil are structurally consistent with one another, zero-sequence magnetic fluxes are offset by one another after the iron core and the coil are connected according to a method, currents with zero-sequence properties are leakage-resistant, and low-resistance channels are provided for harmonic waves with zero-sequence properties, so that the harmonic currents with the zero-sequence properties can flow among a harmonic suppression device for neutral lines of a low-voltage power distribution network and nonlinear loads without flowing into a system, and an effect of suppressing the harmonic waves of the neutral lines can be realized; three core columns are completely spatially symmetrical with one another, so that three phases of magnetic circuits can be distributed uniformly, a zero-sequence magnetic flux compensation effect can be optimized, and the harmonic waves of the neutral lines can be effectively filtered.

Description

Technical field [0001] The invention relates to a filter, in particular to a novel non-resonant passive zero sequence filter Background technique [0002] In the low-voltage power distribution system, the three-phase four-wire power supply mode is the most important power supply mode, which is widely used in industrial sites and civil buildings. With the modernization of the city, a large number of large commercial buildings and office buildings have appeared. In these buildings, there are a large number of personal computers, office automation equipment, inverter air conditioners, lighting power supplies and uninterrupted power supplies and other electrical equipment. These devices will generate a large amount of zero-sequence harmonic currents in the power grid. Even if their single power is small, the harmonic pollution caused by them is extremely serious because of their huge total. The zero-sequence harmonic currents (mainly the third harmonic currents) are superimposed on ...

AI Technical Summary

Problems solved by technology

The harmonic characteristics of the passive filter are greatly affected by the system parameters, and it is easy to be overloaded. The capacitor parameters are easy to change with the aging of the medium, and detuning phenomenon occurs, which reduces the filtering effect, and consumes a lot of materials and has a large volume.

However, active filters have certain problems in terms of cost, reliability, and overload capacity, which limit their wide application.

Images