Stability Study of Low Voltage Electrical Distribution Network: Audit and Improvement of DJEGBE Mini Solar Photovoltaic Power Plant in the Commune of OUESSE (Benin)

The supply of quality energy is a major concern for distribution network managers. This is the case for the company ASEMI, whose subscribers on the DJEGBE mini-power station network are faced with problems of current instability, voltage drops, and repetitive outages. This work is part of the search for the stability of the electrical distribution network by focusing on the audit of the DJEGBE mini photovoltaic solar power plant electrical network in the commune of OUESSE (Benin). This aims to highlight malfunctions on the low-voltage network to propose solutions for improving current stability among subscribers. Irregularities were noted, notably the overloading of certain lines of the PV network, implying poor distribution of loads by phase, which is the main cause of voltage drops;repetitive outages linked to overvoltage caused by lightning and overcurrent due to overload;faulty meters, absence of earth connection at subscribers. Peaks in consumption were obtained at night, which shows that consumption is greater in the evening. We examined the existing situation and processed the data collected, then simulated the energy consumption profiles with the network analyzer “LANGLOIS 6830” and “Excel”. The power factor value recorded is an average of 1, and the minimum value is 0.85. The daily output is 131.08 kWh, for a daily demand of 120 kWh and the average daily consumption is 109.92 kWh, or 83.86% of the energy produced per day. These results showed that the dysfunctions are linked to the distribution and the use of produced energy. Finally, we proposed possible solutions for improving the electrical distribution network. Thus, measures without investment and those requiring investment have been proposed.

Optimal Low-voltage Distribution Topology with Integration of PV and Storage for Rural Electrification in Developing Countries:A Case Study of Cambodia

This paper addresses an optimal design of low-voltage(LV)distribution network for rural electrification considering photovoltaic(PV)and battery energy storage(BES).It aims at searching for an optimal topology of an LV distribution system as well as the siting and sizing of PV and storage over a time horizon of 30 years.Firstly,the shortest-path algorithm(SPA)and first-fit bin-packing algorithm(FFBPA)are used to search for the optimal radial topology that minimizes the total length of the distribution line and improves the load balancing.Then,the optimal siting of decentralized BES(DeBES)is determined using a genetic algorithm(GA)to eliminate the undervoltage constraints due to the load consumption.Two iterative techniques are elaborated to size the maximum peak power of PV and the minimum number of DeBES that can be connected to an LV network without violating the voltage and current constraints.Then,the sizing strategy of centralized BES(CeBES)is developed to avoid reverse power flows into the medium-voltage(MV)network.Finally,a Monte Carlo approach is used to study the impact of load profile uncertainties on the topology.A non-electrified village in Cambodia has been chosen as a case study.