Single-battery power topologies for online UPS systems

摘要

A power converter includes a first power input to receive AC input power, a second power input to receive backup power, a first DC bus configured to provide a positive DC output voltage, a second DC bus configured to provide a negative DC output voltage, and a power conversion circuit coupled to the first DC bus and the second DC bus. The power conversion circuit has an inductor, a first switch device coupled in series with the inductor, a second switch device coupled in series with the first switch device, and a bypass relay coupled in parallel with the second switch device. The power conversion circuit is switchably coupled to the first power input and the second power input, and is operable to charge the inductor and generate the positive and negative DC output voltages.

主权项

1. A power converter, comprising:
a first power input to receive AC input power; a second power input to receive backup power; a first DC, bus configured to provide a positive DC, output voltage; a second DC bus configured to provide a negative DC output voltage; and a power conversion circuit, coupled to the first DC bus and the second DC bus, having an inductor, a first switch device coupled in series with the inductor, a second switch device coupled in series with the first switch device, and a bypass relay coupled in parallel with the second switch device, the power conversion circuit switchably coupled to the first power input and the second power input, the power conversion circuit operable to charge the inductor and generate the positive and negative DC output voltages, the power conversion circuit configured to:
in a line mode of operation and during a positive portion of the AC input power, charge the inductor through a first current path of the power conversion circuit that includes the first switch device, the second switch device, the first power input and the inductor;in the line mode of operation and during a negative portion of the AC input power, charge the inductor through a second current path of the power conversion circuit that includes the first switch device, the second switch device, the first power input and the inductor; andin a backup mode of operation. generate the negative DC output voltage through a third current path of the power conversion circuit that includes the second power input, the inductor, the first switch device and the bypass relay, wherein the third current path bypasses the second switch device through the bypass relay.