Shaping control strategies for active power filters

Abstract

This study presents a general control strategy for active power filters derived from the current-shaping principle previously employed in shunt active filters. The generalisation introduced here and denoted as voltage-current shaping control, exploits the symmetry between the possible wave-shaping solutions, and can be applied to shunt, series, and more complex networks of active filters. Moreover, the proposed generalisation allows the synthesis of specific control schemes with a reduced number of sensors. The relevant properties of the proposed schemes in the application of harmonic mitigation are determined. Further, a discussion of the integration of multiple quasi-resonant schemes is presented. Using this approach, it is possible to fine-tune the mitigation of specific components in the harmonic profile from the voltages or currents in the circuit. Experimental results obtained from using a 1 kVA prototype are presented to support the proposed generalisation.

Adapted near‐state PWM for dual two‐level inverters in order to reduce common‐mode voltage and switching losses

“…Different types of inverters, thanks to the recent advances in the field of power electronics industry, are utilised in a wide range of industrial applications, ranging from low-voltage, low-power devices (such as micro-inverters used in household photovoltaic systems [1]) to high-voltage (HV), high-power systems (such as electric motor drive [2], active filters [3,4], and HV direct current electric power transmission systems [5][6][7][8]). Regarding all considerable advantages offered by industrial inverters, all of them -especially multi-level (ML) inverters -suffer from complicated pulse-width modulation (PWM) techniques [9], unbalanced neutral point voltages [10], and so on.…”

Optimization of DC‐link voltage regulator using Bat algorithm for proportional resonant controller‐based current control of shunt active power filter in distribution network

“…The SAPF is forced to track the current reference by any of the current control algorithms used in literature. [13][14][15][16] i *…”

Enhancing the stability of AHF

“…The AHFs are further classified based on the method adapted for controlling their currents, and they are: (i) direct current control schemes and (ii) indirect current control schemes. The direct current control schemes such as hysteresis control [15] realises the reference current tracking by direct control of the power electronic switches, whereas the indirect current control schemes [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] realise the reference current tracking indirectly by appropriately synthesising the inverter voltage. The direct current control schemes can achieve higher bandwidths at the cost of the variable switching frequency.…”

“…In the literature, various current control schemes have been reported for the AHF [10–33]. Some of these schemes strive towards achieving harmonic compensation of the complete harmonic spectrum achieving total harmonic compensation (THC) [20, 25], wherein the upper limit of the harmonic frequency is governed by the control bandwidth of the AHF.…”