Variable time scale optimization of distribution network for distributed photovoltaic access

With the increasing proportion of distributed PV power connected to the distribution grid, the stochasticity and uncertainty of photovoltaic power generation output to the distribution grid brings voltage fluctuations and other adverse effects are becoming more and more obvious. Therefore, this paper proposed a variable time scale optimization active-reactive co-optimization scheme for distributed photovoltaic (PV) access to the distribution network to achieve the purpose of reducing voltage fluctuation and network loss. The optimization is divided into two phases: day-ahead and real-time. The stage of day-ahead is based on an improved multi-objective particle swarm algorithm to derive the scheduling results of the next devices. The real-time phase uses the device scheduling results of the day-ahead phase as the reference trajectory to derive the device scheduling results as well as the optimized voltage and network loss changes. Extensive simulations and comparisons are performed at the IEEE33 node test system. The results show that the model improves the voltage stability of the distribution network containing PV access while reducing the operating costs. The strategy proposed in this paper is effectively validated.