Maintenance method for batteries of frequency modulation energy storage system

Abstract

The invention provides a maintenance method for batteries of a frequency modulation energy storage system. The maintenance method comprises the steps of setting adjusting circuits between battery stacks and between battery clusters in the battery stacks; reading the SOC value, the internal resistance value R and the SOH of each battery or battery module in the energy storage system, judging the deviation amount of the SOC, and carrying out SOC correction on the battery or the battery module with the deviation amount exceeding a limit value; actively adjusting each battery in the same battery cluster to the same SOC value according to the corrected SOC value, and taking the SOC value as the SOC value of the battery cluster; adjusting the SOC values among the battery clusters to the same SOC value; and adjusting the SOC value of each battery stack to a preset value. The daily use of the frequency modulation energy storage system is not affected, the daily charging and discharging energy of the frequency modulation energy storage system can be maximized, the energy waste is further reduced, the service life of each energy storage lithium ion battery is more consistent, and the overall service life of the energy storage system is prolonged.

Description

technical field [0001] The invention relates to the field of battery technology, in particular to a maintenance method for a battery of a frequency modulation energy storage system. Background technique [0002] At present, in the field of frequency modulation energy storage, lithium-ion batteries have become the first choice for frequency modulation energy storage due to their excellent characteristics such as environmental protection, long cycle life, and high power density, and have been widely used. Frequency modulation energy storage Since the lithium-ion battery is in a long-term working state, at present, most of its maintenance is regularly maintained or maintained when it is abnormal. The maintenance is mainly to calibrate the SOC state of the battery, and screen the internal resistance and health of the battery. to keep the system working properly. [0003] The frequency modulation energy storage system has the characteristics of high and variable use rate and lon...

AI Technical Summary

Problems solved by technology

When the battery stack withdraws from the energy storage system, it will affect the charging and discharging capacity of the energy storage system, reducing the income, and the maintenance will take a long time and high maintenance cost

[0005] In the field of frequency modulation energy storage, the continuous and changeable AGC command causes the lithium-ion battery to be in the process of continuous charging and discharging at different rates, so the SOC of the battery is difficult to measure

Due to the long maintenance interval of the battery system, the method of withdrawing the battery stack when an abnormality occurs will cause aggravated differences between lithium-ion batteries. This difference will lead to accelerated deterioration of batteries with poor performance over time, which will affect the frequency modulation energy storage system. Life expectancy, and maintenance time is longer, which eventually leads to a significant reduction in the revenue of frequency regulation energy storage

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