Patent attributes
Systems and methods are provided for an uninterruptable power supply having a positive DC bus, a neutral DC bus, and a negative DC bus. The uninterruptible power supply includes a battery charger circuit having an inductor, a first charger output, and a second charger output. A first switch connected to a first end of the inductor is configured to couple the positive DC bus with the first charger output. A second switch connected to a second end of the inductor is configured to couple the negative DC bus with the inductor. The neutral DC bus can be coupled to the second charger output. The battery charger circuit can be configured to draw power from at least one of the positive DC bus and the negative DC bus to charge a battery coupled to the first charger output and the second charger output.