Voltage Control Strategy Using the Rule-Based Reasoning in LV Distribution Networks with PV Penetration Integrating OLTC-Fitted Transformer

A voltage control strategy using the rule-based reasoning (RBR) for On-load Tap Changer (OLTC)-fitted transformer, which could be integrated successfully into the low voltage electric distribution networks (LV EDNs) with different photovoltaic (PV) penetration degrees, has been proposed in the paper. Testing their efficiency has been done in a real LV EDN belonging to a Romanian Distribution Network Operator. The results of the simulation process indicated an improvement of the voltage quality indicators (the maximum voltage and the average voltage deviation during the analyzed period, 24 hours, at the end-users level) following the application of the RBR, mitigating the intermittency of injected powers by the PV prosumers with the positive impact on the operation of the LV EDNs. Also, the limit threshold of the penetration degree (50%) identified over which the efficiency of the proposed voltage control strategy integrating OLTC-fitted transformer decreases, considering the input data and the working assumptions used in the simulation process.