Electrolyte flow dynamic control system and method based on vanadium battery SOC estimation

Abstract

The invention discloses an electrolyte flow dynamic control system based on vanadium battery SOC (State of Charge) estimation, which is characterized in that a plurality of vanadium battery stacks are connected in series between the positive electrode and the negative electrode of an energy storage converter, and the electrolyte of two adjacent vanadium battery stacks is communicated through an electrolyte pipeline; the electrolyte of the vanadium battery test pile is communicated with the electrolyte of one of the vanadium battery piles through an electrolyte pipeline, and the energy storage converter is used for controlling all the vanadium battery piles connected in series to charge and discharge; and the battery management system adjusts the frequency of a frequency converter of a pipeline system of the vanadium battery energy storage system according to the charge state changing along with the time, and dynamically controls the flow of electrolyte in the vanadium battery energy storage system. Under the condition that the SOC value is dynamically obtained, the electrolyte flow is dynamically controlled, data are continuously accumulated through the BMS, appropriate electrolyte flow values of the SOC in different areas are fitted, and it is guaranteed that the charging and discharging energy efficiency of the system is always in a high level state.

Description

technical field [0001] The invention relates to the technical field of vanadium battery energy storage, in particular to a dynamic control system and method for electrolyte flow based on vanadium battery SOC (state of charge) estimation. Background technique [0002] Corresponding release of energy storage documents on the grid side, power supply side, and user side. As an important member of the energy storage family, all-vanadium redox flow batteries are becoming more and more perfect as the vanadium battery energy storage system integration technology is being improved, and the cost of vanadium battery kWh continues to decline. 1. Under the condition that suppliers of vanadium battery energy storage system materials are gradually diversified, the commercial use of vanadium battery energy storage system is becoming more and more popular. [0003] In the battery energy storage system, the state of charge SOC is an important parameter to control the discharge of the system a...

AI Technical Summary

Problems solved by technology

This method is only suitable for laboratory operation, but in actual engineering projects, the charge and discharge of the vanadium battery energy storage system will switch between power mode, current mode, and voltage mode according to needs, while kilowatt-level and megawatt-level energy storage systems Even if the current value at the end of charge and discharge is very high, it does not meet the small current discharge condition of the invention

In the same way, the conversion of SOC value by measuring the concentration of hydrogen ions in the electrolyte through temperature, electrolyte potential, and Nernst equation will be limited by the actual environmental factors of the project site

[0004] The electrolyte flow rate, which also has an important impact on the charge and discharge energy efficiency of the vanadium battery, is still rarely studied in the literature. The current popular method is to use the same constant electrolyte flow rate during the charging and discharging process of the system. Although this treatment method avoids In order to avoid the workload brought by the dynamic control of electrolyte flow rate and flow to system development, it also prevents the impact of electrolyte flow on the charge and discharge energy efficiency of vanadium batteries from being reflected

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