Balancing Series-Connected Electrical Energy Units

摘要

An apparatus and methods to fabricate the apparatus for balancing a string of N series-connected electrical energy units (such as battery cells or modules) comprising: a transformer with a magnetic core and N windings; N switch circuits; N driver circuits, each driver circuit operable to turn ON/OFF a respective switch circuit in a charging or discharging or idling configuration; and a controller circuit. In a novel way, the controller circuit selects each electrical energy unit for charging or discharging or idling, and controls simultaneously coupling all selected-for-discharging electrical energy unit(s) to respective winding(s) in discharging configuration(s) for a first period of time to simultaneously energize the respective winding(s); then immediately or after a short delay, the controller circuit controls simultaneously coupling all selected-for-charging electrical energy unit(s) to respective winding(s) in charging configuration(s) for a second period of time to be charged with respective induced current(s).

主权项

1. An apparatus for balancing a string of N (where N>2) series-connected electrical energy units, the apparatus comprising:
a transformer, the transformer including a magnetic core and N windings corresponding to the N electrical energy units; N switch circuits corresponding to the N electrical energy units, each switch circuit including a plurality of electronic switches operable to couple a respective electrical energy unit to a respective winding in a discharging configuration, or to couple the respective electrical energy unit to the respective winding in a charging configuration, or to uncouple the respective electrical energy unit from the respective winding in an idling configuration; N driver circuits, being respectively coupled to the N switch circuits, each driver circuit being operable to turn ON/OFF electronic switches of a respective switch circuit; and a controller circuit, being coupled to the N driver circuits, and operable to select each electrical energy unit for charging or discharging or idling, and operable to control simultaneously coupling all selected-for-discharging electrical energy unit(s) to respective winding(s) in discharging configuration(s) for a first period of time to simultaneously energize the respective winding(s) to store some energy in the magnetic core, then immediately or after a short delay, operable to control simultaneously coupling all selected-for-charging electrical energy unit(s) to respective winding(s) in charging configuration(s) for a second period of time to be charged with respective current(s) induced from the stored energy in the magnetic core.