Parallel operation of active and passive filters for variable speed cycloconverter drive systems

Abstract

A passive filter has the following drawbacks.It hardly compensates harmonics which frequencies * It causes a parallel resonance, a series resonance, or These drawbacks of the passive filter can be alleviated by the combined use of the active and passive filters and by appropriately coordinating their operations. That is, of the harmonics generated by the cycloconverter, the varying frequency components are absorbed by the active filter' and the fixed frequency components by the passive filters. This provides a good harmonic compensation over the entire operation range for the irregularly varying frequency harmonic current generated by the cycloconverter. In addition, this arrangement suppresses parallel and series resonances.The authors prepared a digital simulation program consisting of a passive filter, active filter, cycloconverter and power supply system and studied a variety o f combinations of passive and active filters in terms of harmonic compensation, parallel resonance suppression, and series resonance suppression. This paper describes the passive and active filter combination techniques and t h e characteristics of each combination. are constantly changing. both which distorts voltages.

A novel control method of PAPF for harmonics compensation and resonance damping in power system

“…Appling PAPF in the power transmission/distribution system that contains capacitors is an effective way to suppress harmonic distortion. However, it is obtained from industrial applications that the capacitors can influence the system stability when PAPF using traditional load current detecting method [11][12][13][14][15]. In this paper, a novel control method of PAPF is proposed to improve the system stability and achieve better compensation performance.…”