Optimal Two-Level Allocation of Grid-Connected Capacity of PV Plants Based on Multi-state Modeling

In the grid-connected system of independently operating photovoltaic power plants with a high proportion of access to renewable energy, the uncertainty and fluctuation of its output and load power, and the existence of waste of renewable energy, optimize the configuration of photovoltaic and energy storage capacity so that the operation of the whole photovoltaic power plant achieves the minimum investment construction cost and operation cost economy. A two-layer optimization model is used in capacity optimization planning. The outer model deals with PV output and load through multi-state theory to establish a capacity optimization model under an uncertainty framework, while the inner model considers operational costs and energy storage life loss during operation. Using the rain flow counting method to calculate the energy storage life, the various factors affecting the life of the energy storage equipment can be fully considered. A particle swarm two-layer optimization algorithm is used to calculate the energy storage capacity optimization for grid-connected systems of photovoltaic power plants, and the results verify the feasibility of this method.