Method for realizing active equalization among battery pack modules and circuit

Abstract

The invention provides an equalization method and a circuit, and particularly relates to a method for realizing active equalization among battery pack modules and a circuit. The method for realizing active equalization among the battery pack modules includes detecting voltage of the various battery pack modules; sorting the voltage of the battery pack modules; finding the battery pack module with the maximum voltage and the battery pack module with the minimum voltage; and charging the battery pack module with the minimum voltage by the battery pack module with the maximum voltage when voltage difference between the two battery pack modules reaches a set equalization standard voltage difference value. The battery pack module with the maximum voltage charges the battery pack module with the minimum voltage in a constant-voltage current limiting mode, the maximum output voltage is voltage of the battery pack module, and output current is equalizing effective current. By the aid of the method and the circuit, power equalizing devices, inductance devices and the like are omitted, conduction and radiation are effectively controlled, active equalizing current is increased, active equalization efficiency is improved, cost of an equalization module is lowered, and EMC (electro-magnetic compatibility) and EMI (electro-magnetic interference) of the integral circuit are controllable.

Description

technical field [0001] The invention provides an equalization method and circuit, in particular to an active equalization method and circuit between battery pack modules. Background technique [0002] Under the premise of the development of today's society, lithium batteries are accompanied by applications such as electric vehicles, hybrid vehicles, base stations, backup power supplies, mobile power supplies, and grid energy storage. Battery series connection has been widely used in various applications. However, this series of battery pack modules has brought great trouble to the management system-the capacity mismatch between the single cells and the battery modules. This problem will become more and more serious with the prolongation of use time, and eventually lead to the complete failure of the battery - can not charge, can not discharge. [0003] Of course, the solution to this problem is equalization technology. So far, many engineers have adopted resistance consum...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the embodiments of the present invention is to provide an active equalization method and circuit between battery pack modules, aiming to solve the problem that the existing resistance consumption equalization technology has no effect in high-power fast charging and discharging appliances, and the existing active equalization technology Due to the use of the principle of switching power supply, it is very troublesome in terms of EMC, and the current equalization technology realized by using the flying capacitor mode will not have a long service life if ordinary relays are used, and the problem of expensive semiconductor photo-controlled relays

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