Voltage control in distribution networks with penetration of solar PV: Estimated voltages as a control input

摘要

This paper analyses the effectiveness of voltage estimations used as a new control logic for a traditional 110/20kV Medium Voltage (MV) On-Load Tap Changing (OLTC) transformer in order to regulate over-voltages in a residential Low Voltage (LV) network. This study is carried out on a radial distribution feeder modelled in MATLAB and simulations are run for 24 hour periods. A number of cases were tested to observe the effectiveness of voltage estimation as control logic with varying Photovoltaic (PV) penetrations. For a number of test cases, PV is not evenly distributed on each phase, leading to an unbalance between the three phases, a realistic possibility in future networks. The voltage estimation control logic is compared to traditional OLTC voltage regulation for each test case. This initial study indicates that voltage estimations prove more effective at reducing over-voltages caused by PV in the LV network than traditional OLTC regulation for this network. Voltage unbalance was observed to lead to under-voltages at times for both cases, indicating the requirement for additional voltage regulators in the network.