Optimal multiobjective design of hybrid active power filters considering a distorted environment

Abstract

Abstract-The development of new passive, active and hybrid filtering techniques is important, and the issues of higher quality, reduced complexity, higher efficiency, and lower cost are important conditions that need to be addressed with regard to the expected stringent trends in power quality obligations. This paper suggests a new approach for the optimal sizing of hybrid active power filter (HAPF) parameters, presented for three-phase industrial power systems. Hybrid filter topology can be used to compensate harmonic currents as well as for power factor corrections, without concern for importing and exporting harmonics, or simply the series and parallel resonance that may occur. The new trend in harmonic power filter design is not to obtain the best solution from a single objective optimization, but to obtain a good compromise solution accomplished under other conflicting objectives. FORTRAN Feasible Sequential Quadratic Programming (FFSQP) is used to determine the proposed filter optimal sizing to minimize the total voltage harmonic distortion as the main objective function, where maintaining the load power factor at an acceptable limit is desired. If the total harmonic voltage distortion achieves the specified goal, then the objective is redirected into minimizing the resultant voltage and current total harmonic distortions. The optimal design of the HAPF is analyzed by means of three case studies.

Comparison of Different Optimization Criteria for Optimal Sizing of Hybrid Active Power Filters Parameters

“…Figures (7) - (9) show the effect of variation of K on VTHD, ITHD and PF, respectively, in the nonlinear problem: Objective 2, Case 4. Roughly speaking, large values of K (K>12) improve the hybrid active/passive filter compensation performance [10]. Table V shows the frequency responses of the attenuation factor and ratio of |Z/Z R | before and after compensation (i.e.…”

“…The ratio of the source harmonic current to the load current under the assumption of V Sn equals zero is given in Equation (10). The amplitude of (10) is called "attenuation factor, AF".…”

“…The active filter is controlled as a current-controlled voltage-source system. Recalling [10], the voltage-source converter of the HPF is recognized to suppress harmonic current and enhance the passive facility performance by introducing a voltage-harmonic waveform at its terminals, given as n S n V K*I (1)  where: n is the harmonic order and K is the gain of controlled voltage-source. It is intended to come to zero at the fundamental frequency (n=1).…”

Overview of power quality analysis and control technology for the smart grid

“…[44] presents a multi-PR current controller based on the circuit model, which simplifies the harmonic extraction unit. [45] describes a control method with decoupled fundamental component and harmonic component, resulting in dispensable unit for the harmonic voltage and current detection. Dividing frequency control proposed in [8] and [46] reduces the compensation error of the harmonic current's amplitude and phase, which is suitable for multi-structure active power filters.…”

Influence of data resolution in nonlinear loads model for harmonics prediction

“…Usually, the simplest models of harmonics produced by rectifiers used in the literature, consider that such loads behave as ideal current sources (Norton model with infinite impedance) [8]- [11]. If such behavior were true, the harmonic currents generated by the nonlinear loads (NLL) would not depend on external circumstances such as: harmonics of the supply voltage, supply impedance, harmonics produced by other parallel disturbing loads or on the eventual parallel connection of an active or passive filter (APF) ( Fig.…”