A Harmonic Mitigation Method Based on the PV and ESS Collaborative Operation

The rapid development of new power systems has placed new demands on the quality of power supply to the grid. A large number of new energy systems connected to the distribution networks, such as photovoltaic (PV) and energy storage systems (ESS), can be used to suppress harmonics in the distribution networks because their grid-connected inverters are similar to the topology of power quality control devices. In this paper, an optimization model is proposed for the harmonic mitigation of multiple harmonic sources (HSs) using PV-ESS inverters in synergy, in the scenario where the degree of the grid-wide harmonic distortion is known. With the optimal harmonic level of the whole network as the objective function, and the power flows, bus voltages, total harmonic distortions of voltage, inverter capacities and harmonic mitigation costs as constraints, the PV and ESS in the distribution network are jointly controlled to suppress the harmonics of the whole network, which could also reduce the mitigation costs. The validity and economics of the proposed method have been analyzed in the case studies using a modified IEEE 13 bus test feeder.