Patent ID: 8120322

Claim:
A charge equalization apparatus for equalizing charges of M*N batteries, the charge equalization apparatus being configured such that the M*N batteries are connected in series and are divided into N battery modules, each having M series-connected batteries, comprising: N intra-module charge equalization units, each connected in parallel with respective M series-connected batteries existing in each battery module, supplied with charge from the M series-connected batteries, and configured to discharge overcharged batteries and to charge undercharged batteries, thus equalizing charges of the M series-connected batteries; an inter-module charge equalization unit connected in parallel with respective N battery modules and configured to discharge overcharged battery modules, among the N battery modules, and to charge undercharged battery modules, thus equalizing charges of the N battery modules; a voltage detection and drive signal generation unit configured to detect voltages of respective M*N batteries, to set an average voltage of the detected voltages as a reference voltage, to generate a drive signal using both the detected voltages and the reference voltage, and to control driving of the N intra-module charge equalization units and the inter-module charge equalization unit by providing the generated drive signal to the N intra-module charge equalization units and the inter-module charge equalization unit; and wherein each of the N intra-module charge equalization units comprises: M first transformer units respectively connected in parallel with the M series-connected batteries, and configured to store a charge supplied by the M series-connected batteries and to supply the stored charge to undercharged batteries among the M series-connected batteries, thus equalizing charges of the M series-connected batteries; M charge/discharge control switches connected between first ends of primary windings of the first transformer units and an anode of a first battery of the M series-connected batteries so as to supply a charge supplied by the M series-connected batteries to the primary windings of the transformer units; and M first semiconductor switching devices connected between first ends of secondary windings of the first transformer units and anodes of the M series-connected batteries so as to prevent a charge supplied by the M series-connected batteries from being supplied to the secondary windings of the first transformer units.