Battery dynamic grouping system and operation control method thereof

Abstract

The invention relates to a battery dynamic grouping system based on modular bidirectional charge and discharge controllers. The system comprises the plurality of modular bidirectional charge and discharge controllers, a series access switch, a parallel access switch, a bypass switch, a plurality of battery energy storage units and a dynamic battery pack operation management system. Each battery energy storage unit accesses a low voltage side of the corresponding modular bidirectional charge and discharge controller, and high voltage sides of the modular bidirectional charge and discharge controllers carry out serial-parallel dynamic connection via the series access switch and the parallel access switch, and then access a direct current bus of the battery dynamic grouping system. The dynamic online series-parallel grouping of the battery energy storage units can be realized, and the charge and discharge process of each battery energy storage unit can be accurately managed, which can effectively improve the operational reliability and stability of a large-scale battery grouping system.

Description

technical field [0001] The invention belongs to the technical field of energy storage, and relates to a battery dynamic grouping system based on a modular bidirectional charge-discharge controller and an operation control method thereof. Background technique [0002] Among many energy storage methods, battery energy storage technology has developed the most rapidly and the technology is relatively mature. As an energy storage unit, batteries have been widely used due to their high energy storage density and cost performance. However, due to the limited voltage and capacity that a single battery can provide, it cannot meet the needs of practical applications in most cases, so it is necessary to connect multiple batteries in series or parallel to build a battery pack to meet the requirements of the system. Due to differences in internal characteristics such as internal resistance of each single cell, the operating state of each cell in the battery pack cannot be kept consisten...

AI Technical Summary

Problems solved by technology

However, since the conventional battery management system (BMS) is essentially unable to accurately manage the charging and discharging process of each battery cell, the design and strategy of its active equalization circuit face great challenges. Very limited reliability during operation

At the same time, the use of the battery management system (BMS) cannot solve the problem of the outage of the large-scale battery pack system caused by the failure of a single battery. The faulty battery must be replaced manually to restore the operation of the large-scale battery pack system.

However, the internal characteristics of the replaced new single cells are quite different from those of the original single cells in the large-scale battery pack system, which will significantly increase the difficulty of operation control of the battery management system (BMS) after the replacement of single cells

With the continuous replacement of new single batteries, the operating reliability of the battery pack system will be significantly reduced

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