All-vanadium redox flow battery energy storage system equivalent method based on electric-thermal coupling

Abstract

The invention discloses an all-vanadium redox flow battery energy storage system equivalence method based on electric-thermal coupling. The method comprises: 1, performing modeling on electrical characteristics of a VRB according to a second-order resistance-capacitance network; 2, performing parameter identification by using a particle swarm algorithm; 3, analyzing the heat production condition of each module in the operation of the battery; 4, analyzing the heat transfer process of the VRB system; 5, based on an electric-thermal ratio fitting principle, a heat transfer path being equivalent; and 6, combining all the states obtained in the step 2 and the step 5 to obtain a complete state space equation of the VRB energy storage system electric heating coupling model. According to the method, the electrical characteristics and the heat generation characteristics of the VRB energy storage system during operation and the coupling relation between the electrical characteristics and the heat generation characteristics are comprehensively considered, the charge state, the terminal voltage and the temperature states of all parts of the battery can be accurately predicted, and safe and stable operation of the VRB is effectively guaranteed.

Description

technical field [0001] The invention relates to the technical field of electric power system battery modeling, specifically refers to an equivalent method for an all-vanadium redox flow battery energy storage system based on electrothermal coupling, and proposes an electrical equivalent model suitable for power grid energy storage system simulation. Background technique [0002] With the aggravation of environmental pollution and energy crisis, it is particularly important to use renewable energy such as solar energy, wind energy, and water energy to generate electricity. However, the inherent randomness and intermittent characteristics of renewable energy seriously hinder the safe and economical operation of the grid system. The dispatchability of the energy storage system can effectively improve the problems caused by the instability of new energy power generation. All-vanadium redox flow batteries have become one of the preferred technologies for large-scale energy stora...

AI Technical Summary

Problems solved by technology

Improper temperature control will lead to precipitation of reactants and even blockage of flow channels, which will affect the safe and efficient operation of the battery

However, the existing electrical equivalent models do not consider the influence of temperature on the external characteristics of flow batteries

In the current research, the patent "An Equivalent Simulation Method for All Vanadium Redox Flow Battery Energy Storage System" (Patent No.: 201410089721.4) proposed a second-order dynamic equivalent model; ") compared and analyzed the basic principles and respective characteristics of different equivalent circuit models, and proposed a commonly used equivalent model; The vanadium redox flow battery energy storage system modeling research is carried out. In this paper, it is assumed that the temperature remains constant during the reaction process, and the error caused by the large difference between the set temperature and the actual operating temperature is not considered.

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