초록 ▼

An equalizer for equalizing the charge on several series-connected cells includes a transformer having plural windings on a core corresponding to the number of cells. The windings are tightly coupled to one another. A switching device such as a MOSFET is connected to each of the windings, and a wind

An equalizer for equalizing the charge on several series-connected cells includes a transformer having plural windings on a core corresponding to the number of cells. The windings are tightly coupled to one another. A switching device such as a MOSFET is connected to each of the windings, and a winding and a switching device are connected across each of the cells. The switching devices are simultaneously switched at a relatively high frequency, e.g., 20 Hz, and the voltage across the highest charged cell appears across each of the windings when the switching devices are on. Current flows from the most highly charged cell to a cell or to cells of lower charge, with the charging current being proportional to the difference in voltage between the highest charged cell and each of the lesser charged cells. Equalization is carried out with very little power consumption by the equalizer, allowing charging to take place in a rapid manner.

대표청구항 ▼

A method of equalizing the charge on two or more cell units connected in series, comprising the steps of: (a) providing a transformer having two windings on a core for each cell unit, the two windings for each cell unit connected in parallel to such cell unit, the two windings for each cell unit com

A method of equalizing the charge on two or more cell units connected in series, comprising the steps of: (a) providing a transformer having two windings on a core for each cell unit, the two windings for each cell unit connected in parallel to such cell unit, the two windings for each cell unit comprising a first winding and a second winding, each of the first windings having the same number of turns and being tightly coupled to one another and each of the second windings having the same number of turns and being tightly coupled to one another; and (b) simultaneously electrically connecting each one of the first or second windings to one of the cell units for a selected period of time such that the voltage at the highest charged cell unit appears across each of the windings to transfer energy from the most highly charged cell unit to a cell unit of lower charge, and then simultaneously disconnecting the windings from the cell units, wherein the step of simultaneously electrically connecting and disconnecting is carried out alternatively for the first windings and then the second windings, and repeating the step of connecting and disconnecting the windings from the cell units at a selected frequency thereby to equalize the charge on the cell units.