Abstract: According to at least one aspect of the disclosure, an inverter is provided comprising an input configured to receive input DC power from a DC source, an output configured to provide output AC power to a load, a plurality of DC rails coupled to the input and configured to receive the input DC power from the DC source, a plurality of switches coupled between the plurality of DC rails and configured to convert the input DC power into the output AC power, each switch of the plurality of switches having a parasitic capacitance, and at least one ZVS network coupled across at least two switches of the plurality of switches, the ZVS network including at least two inductors configured to resonate with the parasitic capacitance of at least one switch of the plurality of switches to provide soft switching of at least one switch of the plurality of switches.

Abstract: According to one aspect, embodiments of the invention provide an electrical-converter system comprising a printed circuit board including at least a first layer and a second layer, a switching node disposed on the second layer, a first transistor, a second transistor, a third transistor, and a fourth transistor disposed on the first layer, a first conduction path from a source of the first transistor, through the switching node, to a drain of the fourth transistor, the first conduction path having a first length, and a second conduction path from the source of the first transistor, through the switching node, to a drain of the second transistor, the second conduction path having a second length, wherein the first length of the first conduction path is greater than the second length of the second conduction path.

Abstract: A power system includes a base module including a system management controller (SMC) and a power distribution unit (PDU), an uninterruptible power supply (UPS) module including a UPS, and a battery module including a battery. The base module includes a first edge, and the battery module is detachable from UPS module in a direction perpendicular to the first edge.

Abstract: According to at least one aspect of the disclosure, an inverter is provided comprising an input configured to receive input DC power from a DC source, an output configured to provide output AC power to a load, a plurality of DC rails coupled to the input and configured to receive the input DC power from the DC source, a plurality of switches coupled between the plurality of DC rails and configured to convert the input DC power into the output AC power, each switch of the plurality of switches having a parasitic capacitance, and at least one ZVS network coupled across at least two switches of the plurality of switches, the ZVS network including at least two inductors configured to resonate with the parasitic capacitance of at least one switch of the plurality of switches to provide soft switching of at least one switch of the plurality of switches.

Abstract: According to at least one aspect of the disclosure, an inverter is provided comprising an input configured to receive input DC power from a DC source, an output configured to provide output AC power to a load, a plurality of DC rails coupled to the input and configured to receive the input DC power from the DC source, a plurality of switches coupled between the plurality of DC rails and configured to convert the input DC power into the output AC power, each switch of the plurality of switches having a parasitic capacitance, and at least one ZVS network coupled across at least two switches of the plurality of switches, the ZVS network including at least two inductors configured to resonate with the parasitic capacitance of at least one switch of the plurality of switches to provide soft switching of at least one switch of the plurality of switches.

Abstract: According to one aspect, embodiments herein provide a power switching circuit, comprising a first terminal, a second terminal, a third terminal, and a plurality of switching devices, each switching device having a first transistor having a first gate, a first source, and a first drain, a second transistor having a second gate, a second source, a second drain coupled to the first source, and a bipolar body diode coupled between the second drain and the second source, and a unipolar diode configured to prevent a transition voltage applied across the first gate and the first source from exceeding a degradation threshold of the first transistor during a transition period, wherein a first switching device of the plurality of switching devices is coupled between the first and third terminals and the and a second switching device of the plurality of switching devices is coupled between the second and third terminals.

Abstract: According to at least one aspect of the disclosure, an inverter is provided comprising an input configured to receive input DC power from a DC source, an output configured to provide output AC power to a load, a plurality of DC rails coupled to the input and configured to receive the input DC power from the DC source, a plurality of switches coupled between the plurality of DC rails and configured to convert the input DC power into the output AC power, each switch of the plurality of switches having a parasitic capacitance, and at least one ZVS network coupled across at least two switches of the plurality of switches, the ZVS network including at least two inductors configured to resonate with the parasitic capacitance of at least one switch of the plurality of switches to provide soft switching of at least one switch of the plurality of switches.

Abstract: According to one aspect, embodiments of the invention provide an electrical-converter system comprising a printed circuit board including at least a first layer and a second layer, a switching node disposed on the second layer, a first transistor, a second transistor, a third transistor, and a fourth transistor disposed on the first layer, a first conduction path from a source of the first transistor, through the switching node, to a drain of the fourth transistor, the first conduction path having a first length, and a second conduction path from the source of the first transistor, through the switching node, to a drain of the second transistor, the second conduction path having a second length, wherein the first length of the first conduction path is greater than the second length of the second conduction path.

Abstract: According to one aspect, a DC power supply is provided. The power supply includes a first input configured to be coupled to an AC power source, a second input configured to be coupled to a battery, an output, a transformer, and a controller coupled to the transformer. The transformer includes a first winding configured to be coupled to the first input, a second winding configured to be coupled to the second input, and a third winding configured to be coupled to the output. The controller controls, in a first mode, the first winding to generate, based on power received from the AC power source, a first voltage across the second winding to charge the battery, and a second voltage across the third winding, and control, in a second mode, the second winding to generate, based on power received from the battery, a third voltage across the third winding.

Abstract: A system for monitoring a fan used to cool equipment includes memory storing controller-executable instructions, and a controller configured to execute the instructions, which cause the controller to operate a fan, perform a deceleration test on the fan to obtain deceleration test data, calculate a variance of the deceleration test data, make a determination that the fan is susceptible to imminent failure based on the variance, and generate a signal for the equipment to enter a low-heat producing mode based on the determination.

Abstract: According to one aspect, embodiments herein provide a power switching circuit, comprising a first terminal, a second terminal, a third terminal, and a plurality of switching devices, each switching device having a first transistor having a first gate, a first source, and a first drain, a second transistor having a second gate, a second source, a second drain coupled to the first source, and a bipolar body diode coupled between the second drain and the second source, and a unipolar diode configured to prevent a transition voltage applied across the first gate and the first source from exceeding a degradation threshold of the first transistor during a transition period, wherein a first switching device of the plurality of switching devices is coupled between the first and third terminals and the and a second switching device of the plurality of switching devices is coupled between the second and third terminals.

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: 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: According to one aspect, a DC power supply is provided. The power supply includes a first input configured to be coupled to an AC power source, a second input configured to be coupled to a battery, an output, a transformer, and a controller coupled to the transformer. The transformer includes a first winding configured to be coupled to the first input, a second winding configured to be coupled to the second input, and a third winding configured to be coupled to the output. The controller controls, in a first mode, the first winding to generate, based on power received from the AC power source, a first voltage across the second winding to charge the battery, and a second voltage across the third winding, and control, in a second mode, the second winding to generate, based on power received from the battery, a third voltage across the third winding.

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 UPS system comprising an input, an output, a converter, an inverter configured to convert DC power into output AC power, and a controller configured to operate the inverter to introduce a voltage droop to the output AC power, wherein the controller includes an active power droop controller including a first moving average filter configured to sample instantaneous active power of the inverter to obtain instantaneous active power samples and calculate a first DC component of the instantaneous active power samples, and a first Min-Max filter configured to receive the first DC component of the instantaneous active power samples and output a second DC component of the instantaneous active power samples having a convergence time less than the first DC component, wherein the active power droop controller is configured to calculate the voltage droop based on the second DC component.

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 UPS system comprising an input, an output, a converter, an inverter configured to convert DC power into output AC power, and a controller configured to operate the inverter to introduce a voltage droop to the output AC power, wherein the controller includes an active power droop controller including a first moving average filter configured to sample instantaneous active power of the inverter to obtain instantaneous active power samples and calculate a first DC component of the instantaneous active power samples, and a first Min-Max filter configured to receive the first DC component of the instantaneous active power samples and output a second DC component of the instantaneous active power samples having a convergence time less than the first DC component, wherein the active power droop controller is configured to calculate the voltage droop based on the second DC component.

Abstract: According to one aspect, embodiments herein provide a bidirectional converter comprising a first interface, an input bridge coupled to the first interface, an inverter portion coupled to the input bridge and comprising a first bidirectional converter, a second bidirectional converter, and an output filter coupled to the first bidirectional converter and the second bidirectional converter, a second interface coupled to the output filter, and a controller configured to operate the input bridge to draw DC power from a DC source and provide power to the inverter portion, to operate, in a first mode, the first bidirectional converter, in conjunction with the output filter, to generate a positive half cycle of an output voltage waveform at the second interface, and to operate, in a second mode, the second bidirectional converter, in conjunction with the output filter, to generate a negative half cycle of the output voltage waveform at the second interface.