Charging and discharging dynamic voltage-balancing circuit and power supply using same

Abstract

The invention relates to a charging and discharging dynamic voltage-balancing circuit which is applied to a power supply composed of multiple cell units which are connected in series. In the process of discharging the power supply, when a first transistor is on, the power supply charges the cell units with relatively low voltage out of the multiple cell units on a priority basis and enables the multiple cell units to reach balanced voltage; while in the process of charging the power supply, when a third transistor is off, a primary winding, the first transistor and the power supply form a BUCK follow current loop, so as to charge the cell units with relatively low voltage out of the multiple cell units on a priority basis and enable the multiple cell units to reach balanced voltage. The invention also relates to a power supply using the charging and discharging dynamic voltage-balancing circuit. In the invention, through the relation of an original secondary winding of the transformer, Ton time slot in the discharging process of a BOOST circuit and Toff time slot in the charging process of the BUCK circuit are effectively utilized to carry out dynamic voltage balancing on the cell units which are connected in series in the power supply.

Description

technical field [0001] The invention relates to the technical field of battery energy storage, and more specifically, to a charging and discharging dynamic voltage equalization circuit and a power supply using the circuit. Background technique [0002] With the introduction of the national smart grid concept, more and more large-scale energy storage systems are being used. At present, no matter whether traditional lead-acid batteries are used or new lithium batteries, lithium-iron batteries or super capacitors are used, there is a fatal problem, that is, the battery Unit series voltage equalization problem. [0003] The traditional power supply composed of series battery cells adopts a voltage equalizing circuit in the process of charging and discharging, which mainly achieves the purpose of voltage equalizing by consuming energy, and has a short life. In addition, there are the following disadvantages: [0004] First, energy is consumed unnecessary, which reduces system ef...

AI Technical Summary

Problems solved by technology

[0008] The technical problem to be solved by the present invention is to provide a voltage equalization circuit in the prior art for the defects of large energy consumption, low voltage equalization accuracy, complex debugging and control circuits, and inability to ensure voltage equalization during discharge and dynamic processes. Charge and discharge dynamic voltage equalization circuit and power supply using the circuit

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