Harmonic current counteracting module

Abstract

The invention discloses a harmonic current counteracting module which comprises a direct-current voltage-stabilizing and current-tracking control unit, a drive unit, a three-phase full-bridge conversion circuit, a direct-current voltage-stabilizing capacitor bank, a three-phase single-harmonic filter circuit, a current sensor and a voltage sensor. The invention also discloses a harmonic current counteracting module group consisting of the harmonic current counteracting modules, and the harmonic current counteracting modules are connected in parallel and then connected with a low-voltage powerdistribution busbar through a circuit breaker. The harmonic current counteracting module is convenient for standardized protection by adopting a module structure, is convenient for dilatation, can improve system operation reliability due to N+1 redundancy, and has a harmonic current counteracting effect due to counteracting aiming at single power harmonic and reasonable design of the filter circuit.

Description

technical field [0001] The invention relates to a low-voltage electric power distribution system, in particular to a harmonic current cancellation module applied to the system. Background technique [0002] With the extensive use of semiconductor devices in power systems, the harmonic hazards caused by nonlinear loads have begun to attract attention, and the harmonic problems in low-voltage power distribution systems have also attracted more and more attention. For harmonic suppression and elimination, the main means are adding passive power filter, active power filter and other devices on the power distribution system side; or adding power factor correction links on the power consumption side. The passive power filter device mainly adopts the connection combination of reactor and capacitor, and makes the passive power filter device present reasonable impedance to harmonic voltage or harmonic current through series or parallel resonance, so as to achieve the purpose of harmo...

AI Technical Summary

Problems solved by technology

[0003] The above-mentioned methods have been used. Passive power filtering is limited by the influence of its own frequency characteristics due to the connection combination of reactors and capacitors; active power filtering devices suppress harmonics and elimination, the real-time requirements are also very high, the design and production are relatively difficult, and the cost is high; power factor correction is generally only suitable for small and medium power applications because all power will flow through the power conversion circuit

Images