Mitigating distribution feeder voltage rise optimally using an on-load tap changing transformer and smart inverters

Abstract

Higher utilization of distributed generation using solar PV can be observed in recent years due to the gradual reduction of solar panel cost. More additions of solar PV generation in the LV grid can be expected in the future. One of the major challenges encountered by distribution grid operators due to high solar penetration is the voltage rise at the far end of the distribution lines. The centralized control of PV inverters and other controllable devices such as on-load tap changer transformers are a potential solution to solve the voltage rise problem. Optimum centralized control is a heavily investigated topic in the recent past. The optimum control of controllable devices in LV grids can prevent the voltage rise while minimising the energy loss due to resistive loss and generation curtailment. Optimum power flow can be utilized for optimum centralized control. Optimum power flow is a non-convex problem, and there are different solutions to solve it. A sequential mixed-integer second-order cone program-based methodology is suggested in this thesis. According to simulation results, the suggested method has a faster execution time and higher accuracy than the methods discussed in the literature. Also, the thesis proves that the voltage rise can be successfully mitigated by applying the proposed algorithm