Abstract: According to one aspect, embodiments herein provide a UPS comprising a transformer including a first primary winding configured to be coupled to a DC source, a second primary winding configured to be coupled to an AC source, and at least one secondary winding, control logic, and at least one output line, wherein the control logic is configured, in a first mode of operation, to enable the first primary winding to generate, based on power received from the DC source, a first output voltage at the at least one output line, and to disable the second primary winding, and wherein the control logic is configured, in a second mode of operation, to enable the second primary winding to generate, based on power received from the AC source, a second output voltage at the at least one output line, and to disable the first primary winding.

Abstract: An uninterruptible power supply system (UPS) includes an interconnect circuit configured to receive three-phase AC input power from an AC power source and a plurality of UPS subsystems each coupled to the interconnect circuit. A first UPS subsystem includes first and second single-phase AC-to-DC converters. At least one second UPS subsystem includes third and fourth single-phase AC-to-DC converters. In a first mode of operation, the interconnect circuit is configured to conduct at least one phase of the AC input power to the first UPS subsystem and at least one phase of the AC input power to the second UPS subsystem, and, in a second mode of operation, to disconnect the AC input power from the first UPS subsystem and to conduct at least one phase of the AC input power to the second UPS subsystem.

Abstract: According to at least one aspect, embodiments herein provide an adaptive battery pack module comprising a Li-ion battery, a low-voltage bus coupled to the Li-ion battery, a bi-directional DC-DC converter coupled to the low-voltage bus, a low-voltage output coupled to the low-voltage bus, a high-voltage output, and a high-voltage bus coupled between the bi-directional DC-DC converter and the high-voltage output, wherein the low-voltage output is configured to be coupled to at least one Li-ion battery of at least one external battery pack module, and wherein the bi-directional DC-DC converter is configured to receive DC power from the Li-ion battery and the at least one Li-ion battery of the at least one external battery pack module via the low-voltage bus, convert the received DC power into output DC power, and provide the output DC power to the high-voltage bus.

Abstract: According to one aspect, embodiments herein provide an AC-DC converter comprising a rectifier, a capacitor, a DC bus coupled to the capacitor, a plurality of first switches coupled to the DC bus, a plurality of second switches coupled between the rectifier and the first switches, a transformer having a primary winding and a secondary winding, the primary winding coupled to the plurality of first switches, the plurality of second switches, and the rectifier, and the secondary winding coupled to an output, and a controller configured, in response to a determination that the input AC power is acceptable, to operate the plurality of second switches and the plurality of first switches such that output DC voltage is maintained at a desired output DC voltage level, and operate the plurality of first switches such that a DC bus voltage on the DC bus is maintained at a desired DC bus voltage level.

Abstract: According to at least one aspect embodiments herein provide a rack power system for providing DC power to equipment installed in a rack, comprising a first shelf containing a plurality of power supplies, each of the plurality of power supplies configured to receive AC power and to provide DC power to equipment installed in the rack, a second shelf containing a plurality of battery units, each of the plurality of battery units configured to provide DC power, and a controller coupled to the first shelf and the second shelf and configured to control each of the plurality of power supplies and configured to control each of the plurality of battery units.

Abstract: According to one aspect, embodiments of the invention provide a method for operating an AC-DC rectifier, the method comprising receiving, with a converter, input AC power having an input AC voltage waveform, controlling, during a positive half line cycle of the input AC voltage waveform, the converter to couple a second DC bus to ground, controlling, during the positive half line cycle of the input AC voltage waveform, the converter to maintain a positive DC link voltage on a first DC bus, controlling, during the positive half line cycle of the input AC voltage waveform, output circuitry to charge a first output capacitor and provide a positive output voltage to a positive output, and discharging, during the positive half line cycle of the input AC voltage waveform, a second output capacitor to provide a negative output voltage to a negative output.

Abstract: According to one aspect, embodiments herein provide a flyback converter comprising an input, an output, a rectifier, a transformer having a primary winding and a secondary winding, a switch, the switch being closed in a first mode of operation and open in a second and third mode of operation, and a regenerative snubber circuit, wherein the flyback converter is configured such that in the first mode of operation, the DC power from the rectifier charges the transformer, wherein the flyback converter is configured such that, in the second mode of operation, the snubber circuit is configured to store leakage energy from the primary winding, and wherein the flyback converter is configured such that, in the third mode of operation, the snubber circuit is configured to provide the stored energy to the primary winding. The flyback converter may also have high power factor at the input while operating from AC input.

Abstract: According to at least one aspect, embodiments herein provide a method for providing regulated DC power to a load, the method comprising receiving input AC power, generating rectified AC power, the rectified AC power derived from the input AC power, converting the rectified AC power into regulated DC output power, and providing the regulated DC output power to an output coupled to the load.

Abstract: According to one aspect, embodiments of the invention provide an inverter system including an input having a positive DC node and a negative DC node coupled to a DC power source to receive input DC power, an output coupled to a load to provide output AC power, a first inverter leg including a first and a second switching device, a second inverter leg including a third and a fourth switching device, the first inverter leg and the second inverter leg being adapted to convert the input DC power to the output AC power, a current sensor coupled to one of the negative and the positive DC node, and a controller assembly adapted to measure a current through the current sensor and determine an inductor current through an inductor coupled to the output, an input current, and an output current based at least on the current through the current sensor.

Abstract: According to at least one aspect, embodiments herein provide a UPS comprising an input to receive input power, an interface to receive DC battery power, a bi-directional converter coupled to the interface and configured to provide DC charging power, derived from the input power, to the battery in a first mode of operation and to convert the DC battery power into backup DC power in a second mode of operation, an output to provide output power to a load derived from at least one of the input power and the backup DC power, and a controller coupled to the bi-directional converter and configured to operate the bi-directional converter at a first frequency in the first mode of operation to generate the DC charging power and to operate the bi-directional converter at a second frequency in the second mode of operation to generate the backup DC power.

Abstract: An uninterruptible power system described herein includes a first input and a second input and an AC output. The uninterruptible power system also includes power circuitry coupled to the first input, the second input, and the AC output, the power circuitry including an inverter having a first pair of switching elements including a first switching element and a second switching element and a second pair of switching elements including a third switching element and a fourth switching element, wherein the first switching element, the second switching element, the third switching element and the fourth switching element have an identical voltage rating; and a controller coupled to the second pair of switching elements and configured to control the third switching element and the fourth switching element to prevent occurrence of an overvoltage condition.

Abstract: An Uninterruptible Power Supply (UPS) system is provided. The UPS system comprises: an input (102) configured to receive input power having an input voltage level, an output (110) configured to provide output AC power to a load, a converter (104) coupled to the input (102) and configured to convert the input power into DC power having a DC voltage level, a DC bus (106) coupled to the converter (104) and configured to receive the DC power, an inverter (108) coupled to the DC bus (106) and configured to convert the DC power from the DC bus (106) into the output AC power and provide the output AC Power to the output (110), and a controller (114) configured to monitor the input voltage level, monitor a level of the output AC power, and operate the converter (104) to regulate the DC voltage level based on the input voltage level and the output AC power level.

Abstract: According to one aspect, embodiments of the invention provide a method for operating an AC-DC rectifier, the method comprising receiving, with a converter, input AC power having an input AC voltage waveform, controlling, during a positive half line cycle of the input AC voltage waveform, the converter to couple a second DC bus to ground, controlling, during the positive half line cycle of the input AC voltage waveform, the converter to maintain a positive DC link voltage on a first DC bus, controlling, during the positive half line cycle of the input AC voltage waveform, output circuitry to charge a first output capacitor and provide a positive output voltage to a positive output, and discharging, during the positive half line cycle of the input AC voltage waveform, a second output capacitor to provide a negative output voltage to a negative output.

Abstract: According to one aspect, embodiments of the invention provide a power system including an input configured to be coupled to a power source and to receive input power from the power source, an output configured to be coupled to a load and to provide output power to the load, a power converter coupled between the input and the output, and an active ripple filter coupled to one of the output and the input including a DC link having at least one DC link capacitor and configured to generate a cancelling ripple voltage to cancel a ripple current associated with the power converter.

Abstract: According to at least one aspect, embodiments herein provide an adaptive battery pack module comprising a Li-ion battery, a low-voltage bus coupled to the Li-ion battery, a bi-directional DC-DC converter coupled to the low-voltage bus, a low-voltage output coupled to the low-voltage bus, a high-voltage output, and a high-voltage bus coupled between the bi-directional DC-DC converter and the high-voltage output, wherein the low-voltage output is configured to be coupled to at least one Li-ion battery of at least one external battery pack module, and wherein the bi-directional DC-DC converter is configured to receive DC power from the Li-ion battery and the at least one Li-ion battery of the at least one external battery pack module via the low-voltage bus, convert the received DC power into output DC power, and provide the output DC power to the high-voltage bus.

Abstract: Systems and methods of operating uninterruptible power supplies in parallel in a power distribution system to provide power to a load are provided. At least one uninterruptible power supply inverter provides power to the load. A communication interface provides a measured value of at least one of inverter output current of a first uninterruptible power supply and a measured value of the load current to a second uninterruptible power supply, and receives a measured value of at least one of inverter output current of the second uninterruptible power supply and the load current. A controller controls the uninterruptible power supplies to operate in one of a master state and a slave state.

Abstract: According to one aspect, embodiments herein provide a UPS comprising a transformer including a first primary winding configured to be coupled to a DC source, a second primary winding configured to be coupled to an AC source, and at least one secondary winding, control logic, and at least one output line, wherein the control logic is configured, in a first mode of operation, to enable the first primary winding to generate, based on power received from the DC source, a first output voltage at the at least one output line, and to disable the second primary winding, and wherein the control logic is configured, in a second mode of operation, to enable the second primary winding to generate, based on power received from the AC source, a second output voltage at the at least one output line, and to disable the first primary winding.

Abstract: According to one aspect, embodiments herein provide a flyback converter comprising an input, an output, a rectifier, a transformer having a primary winding and a secondary winding, a switch, the switch being closed in a first mode of operation and open in a second and third mode of operation, and a regenerative snubber circuit, wherein the flyback converter is configured such that in the first mode of operation, the DC power from the rectifier charges the transformer, wherein the flyback converter is configured such that, in the second mode of operation, the snubber circuit is configured to store leakage energy from the primary winding, and wherein the flyback converter is configured such that, in the third mode of operation, the snubber circuit is configured to provide the stored energy to the primary winding. The flyback converter may also have high power factor at the input while operating from AC input.

Abstract: 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.

Abstract: A power converter includes a battery having a positive terminal and a negative terminal, a first power input to receive AC input power, a second power input to receive DC input power from the battery, a first power output to charge the battery, a second power output to provide power to a load, a rectifier circuit coupled to the first power input, and a non-isolated single-stage power conversion circuit having an input and configured as a buck-boost converter. The power at the second power output is derived from the first power input and/or the second power input. The single-stage power conversion circuit is configured to convert an AC voltage to a DC voltage using a common energy storage element, and is coupled to the first power output and the rectifier circuit.