Optimal Sitting, Sizing, and Operation of Batteries and Passive Filters to Mitigate Over-voltage and Harmonic Problems in Distribution Networks with High Photovoltaic Penetration

Photovoltaic systems (PVs), despite their many advantages, may have effects such as power quality issues (voltage and harmonics increase), short-circuits level increase, protection issues, and transient stability for network. Some of these effects are due to the high PV penetration, which encounters the network with the over-voltage and harmonics problems. In this paper, the location, size and optimal operation of batteries and the passive filters are proposed separately and simultaneously to provide a practical solution to overcome the over-voltage and harmonic problems. In the economic objective function, the fixed and operation costs of batteries and passive filters are considered and constraints are defined to limit the total harmonic voltage and effective voltage of the network buses below the standard ranges. Taking into account the profit of energy arbitrage and reduction of network losses in the objective function, it is concluded that the use of the filter alone has the lowest cost of 736 $ (but results in an effective voltage increase beyond the permissible limit). Also, simultaneous use of battery and filter resulted in the highest loss reduction of 4.1 kWh, with the total harmonic voltage and effective voltage of the network buses are within the 5% range. Also, cables, overhead lines, and transformer are modeled by frequency-dependent characteristics. The studied network is composed of a real low voltage feeder including two PVs; however, in simulations, the PV penetration is increased to study a more challenging situation. Simulations are carried out by using DIgSILENT and MATLAB software and their interface.