Optimal Placement and Sizing of Active Harmonic Filters in Distribution Systems: A Second-Order Cone Programming Approach

Abstract

This research proposes a novel deterministic strategy based on second-order cone programming (SOCP) to solve the problem of optimal placement and sizing of active harmonic filters (AHFs) for unbalanced three-phase four-wire distribution networks with deep penetration of photovoltaic (PV) generation and with nonlinear loads, such as data centers. To conduct the study, the simplified version of the IEEE European Low Voltage Test Feeder (116 buses) extended to a three-phase four-wire power distribution system is used in combination with real measurements (10-minute resolution) of power consumption and harmonic emission collected from a low-voltage-connected data center, a commercial building and a household, according to the European power quality standards IEC 61000-4-30 and IEC 61000-4-7. Real PV power production measurements are also used. Finally, a case study considering three-phase three-wire (3P3W) and three-phase four-wire (3P4W) AHF with different current operating limits is examined. According to the results, AHFs located at the edges of the network, and close to commercial buildings and data centers, injected more distortion current to mitigate voltage distortion. Nevertheless, given the significant neutral current in some buses of the network, 3P3W AHFs were found to be much less effective compared to 3P4W AHFs. In all scenarios considered, the objective function (average voltage distortion) converged to 0.51 V as the current capacity of the AHFs increased, whereas its value without compensation devices was 4.37 V.