Enhanced active power filter and its control strategy

Abstract

The invention discloses an enhanced active power filter and a control strategy of the enhanced active power filter. By judging the running mode of the enhanced active power filter in a power grid system, different load current signals are processed according to the transient-state running mode and the steady-state running mode. The enhanced active power filter has all the functions of a traditional APF, meanwhile, the comprehensive governance capacity for typical transient-state electric energy quality problems such as current surges, transient-state impact and voltage dip is enhanced, and the application range of the enhanced active power filter is expanded to a direct-current system. The enhanced active power filter is favorable for achieving comprehensive governance of transient-state and steady-state electric energy quality problems in alternating-current systems and direct-current systems, the electric energy quality and security stability of a local area network can be improved in an all-dimensional mode, and economic loss is reduced.

Description

Technical field [0001] The invention belongs to the research field of power electronic technology and power quality management, and particularly relates to an enhanced active power filter and its control strategy. Background technique [0002] Since the 1970s, energy conservation and environmental protection have gradually become one of the focuses of the industry. In addition to consuming active power, most electrical loads in the industrial and living sectors require a large amount of reactive power, and even generate harmonic pollution and impulsive power. Power quality issues such as these include steel rolling, cement, papermaking, ships, and petroleum. This is particularly evident in industrial fields such as drilling and automobile assembly, and in public transportation fields such as high-speed railways, urban subways, and electric vehicles. The above-mentioned power quality problems have caused a large amount of power loss, and the direct economic loss is very serious, ...

AI Technical Summary

Problems solved by technology

However, the traditional APF is only suitable for AC systems, and can only control steady-state power quality problems such as harmonics and reactive power, but is basically ineffective for transient power quality problems such as surge current, transient impact, and voltage sag.

However, due to the random changes of a large number of loads, the large-scale access of intermittent energy sources, lightning attacks, and operational interference, especially the switching of impact loads, temporary interruptions in power networks, power distribution systems, and micro-grid systems have been caused. The problem of power quality is becoming more and more obvious, which leads to huge direct economic losses, and seriously threatens the safe and stable operation of the power grid and the normal operation of power loads.

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