Interblock equalization circuit of power battery system and equalization method

Abstract

The invention discloses an interblock equalization circuit of a power battery system and an equalization method; the power battery system formed by linking multiple physically independent battery groups in series is performed with active equalization. The control system adopts a master / slave mode and transmits data information through a CAN bus; the internal equalization and interblock equalization of the battery system are completed by a redundant battery completely; compared with the same type of battery without the interblock equalization function, the power battery system is only added with two equalization power lines for connecting these battery groups together. For the interblock equalization does not need isolation, the outer part is free from additional circuit, and the equalization circuit is not related to the series and parallel linking structures of the battery group; the system and the method are featured by low system cost, simple production and installing techniques of the power battery system, easy maintenance and quick equalization speed.

Description

technical field [0001] The invention belongs to the field of power batteries for electric vehicles, and in particular relates to a method for actively equalizing the capacities of battery packs constituting a new energy vehicle battery system. Background technique [0002] With the increasing popularity and application of electric vehicles, power batteries are becoming more and more widely used. Since single batteries cannot meet the requirements of electric vehicles in terms of voltage and energy, it is necessary to use multiple single batteries to form high voltage and large capacity through series and parallel connection. The power battery system for electric vehicles, and the inconsistency of the internal parameters such as the capacity and internal resistance of the single battery will cause the power battery system to not be able to effectively use its full available capacity, and with the use of the battery, this inconsistency will become more obvious, making the power...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide a method for balancing power battery systems between groups, aiming to solve the above problem of balancing the available capacity among the battery groups in the power battery system of electric vehicles. The battery system includes i×j battery groups, Each battery pack contains P single cells and a redundant battery for balancing within the battery pack and balancing between the battery packs; the battery pack is internally integrated with a local battery management unit, which communicates with the central management unit through the CAN bus Unit communication, the local battery management unit directly controls the on-off of the redundant battery in the battery pack and the balance circuit between the packs or other batteries in the pack

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