The Multi-index Comprehensive Evaluation Method Of Peak Load Shifting Using Battery Energy Storage System

As the battery energy storage has fast response speed and isn’t limited by the geographical conditions and has many other advantages, it is used in power system more and more widely. At present, peak-valley load difference in some parts of the grid is large, which leads to frequent start-stop and operation efficiency drop of the unit. Also, power supply reliability is reduced and power risk of users is increased. Peak load shifting using BESS is an effective way to solve this phenomenon. Peak load shifting using BESS is of great significance.In this paper, a multi-index comprehensive evaluation method is proposed considering economy, reliability and load smoothness, for single evaluation has some limitations in peak load shifting using BESS. The evaluation method considers the effect indicators of battery energy storage system comprehensively, which can analyze and evaluate various schemes. It is more comprehensive and objective compared to a single evaluation index.Peak load shifting optimization model of battery energy storage system(BESS) is proposed firstly, which is solved by using the improved Particle Swarm Optimization(PSO) algorithm containing double loop and disturbed link. Then, the costs and benefits of energy storage battery is analyzed detailed. Considering the influence of depth of discharge of the energy storage battery on its life, calculate the life of battery using the rain flow counting method, which is based on the state of charge(SOC) curve from the result. Analyze the cost and benefit of BESS using present value index method and the concept of "concurrent present value index" is introduced as the economic index with the present value index and investment cost. At last, calculate the reliability index of the system and establish comprehensive evaluation index considering economy, reliability and load smoothness. Different capacity configurations, different limits of discharge times and different types of batteries are analyzed and evaluated. The result shows that the evaluation method can be used to compare peak load shifting of good or bad in a variety of circumstances.