DYNAMIC EQUALIZATION CIRCUIT OF BATTERY MANAGEMENT SYSTEM, AND DYNAMIC EQUALIZATION METHOD THEREFOR

摘要

A dynamic equalization circuit of a battery management system, and a dynamic equalization method therefor. In the circuit, the first cell or the last cell in a group of cells connected in series is connected to a corresponding cell selection switch and a corresponding voltage sample switch by means of a sample wire and an equalization wire separated from each other, respectively; each of the remaining cells is connected to a corresponding cell selection switch and a corresponding voltage sample switch by means of a same wire; during normal operation, and on the basis of impedance values of the sample wires calculated according to a equalization test current condition, a CPU measures sample voltages of the cells and calculates the actual cell voltages by eliminating voltage drops on the wires from the sample voltages, and then performs dynamic equalization control according to the actual cell voltages. The present invention greatly reduces required wire harness cost, and can meet real-time cell voltage sample requirements while equalizing cells, prevent the sample precision from being affected by voltage drops on equalization wires, and make the cell voltage sample correct.