Patent ID: 7378818
Filing Date: 2008-05-27
Classification: B60L,B60W,H01M,H02J,Y02E,Y02T

Abstract:
1. A system, comprising: a string of electrical energy storage units; and a power converter selectively coupled to an individual storage unit of the string of storage units, the power converter being configured to transfer energy bidirectionally between the individual storage unit and the string of storage units, and to balance state of charge of the individual storage unit to a target state of charge, the state of charge of the individual storage unit being determined from an impedance of the individual storage unit, a current of the individual storage unit, and the terminal voltage of the individual storage unit, wherein the power converter comprises: a primary inductor; a first secondary inductor magnetically coupled to the primary inductor; a first switch selectively coupling the individual storage unit to the primary inductor; and the first secondary inductor coupling to an output capacitor; the output capacitor coupled in parallel to the string of storage units; the system further comprises; a first pulse generator configured to provide first enable signals to the first switch; the first switch being configured to couple the individual storage unit to the primary inductor in response to the first enable signals, and to transfer energy from the individual storage unit to the string of storage units, and a second pulse generator configured to provide second enable signals to the first pulse generator; the first pulse generator being configured to provide first enable signals in response to the second enable signals, the second enable signals being capable of controlling a transfer of energy from the individual storage unit to the string of storage units at a controllable rate.