A large-scale flow battery system shutdown protection equipment and its control strategy

Abstract

The invention discloses a large-scale flow battery system shutdown protection device and a control strategy thereof. The control strategy comprises issuing charging and discharging power values and charging and discharging states of a power storage station through a power station monitoring system, dividing battery cells needing shutdown into charging battery cells and shutdown discharging batterycells through a battery management system according to a power storage station charging / discharging rate and a charging coefficient K, charging the charging battery cells through the shutdown discharging battery cells, and repeating the above steps until the battery cells needing shutdown realize shutdown and discharge. The large-scale flow battery system shutdown protection device solves the problem that power cannot be fed back to a power network after shutdown of a large-scale flow battery system, effectively treats pile internal energy, prevents sudden increasing of the temperature in thepile, protects the pile, prolongs a service life of the battery system, maximally improves the use rate and efficiency of the flow battery system and reduces a system energy loss.

Description

technical field [0001] The invention relates to a liquid flow battery system, in particular to a shutdown protection device of a large-scale liquid flow battery system and a control strategy thereof. Background technique [0002] There are a large number of pipelines and electrolytes in the all-vanadium redox flow battery system. After the system is shut down, a certain amount of electrolyte must remain in the stack. The leakage current formed is converted in the form of heat, resulting in an increase in the temperature of the electrolyte. When the flow battery system is charged and shuts down, the remaining electric energy in the stack will be released in the form of leakage. At this time, the electrolyte will no longer flow, causing its temperature to rise rapidly. Once the temperature exceeds the tolerance range of the stack material, it is bound to cause damage to the stack material. Inflict irreversible damage and burn out the stack. Therefore, the processing of energy...

AI Technical Summary

Problems solved by technology

The Chinese patent with the patent number CN103247814 discloses the method of discharging the load, but it is more effective for the all-vanadium redox flow battery system of tens or hundreds of KW. However, with the continuous development of the all-vanadium redox flow battery system, for For MW+ large-scale battery systems, the above methods are difficult to achieve the expected technical effect, the fundamental reason is that it is difficult to find the corresponding matching load

In addition, the above method causes huge energy loss and reduces the working efficiency of the battery system.

To sum up, after the large-scale all-vanadium redox flow battery system shuts down, in order to protect the stack, it is necessary to release the energy of the stack, and the conventional method is not allowed in some occasions.

However, the unloading resistor or load discharge method after the system shuts down is only suitable for small systems, and the large-scale all-vanadium redox flow battery system has a large discharge power when shutting down, and it is impossible to find a suitable load.

Images