Abstract: An electrical power supply system includes a freestanding primary electrical unit, a non-freestanding accessory unit, and an accessory unit support system. The primary electrical unit includes a freestanding cabinet containing a primary electrical component. The accessory unit includes a non-freestanding accessory cabinet containing an accessory electrical component. The accessory unit support system is configured to couple the accessory cabinet to the primary cabinet such that the accessory unit is thereby structurally supported by the primary electrical unit. The accessory cabinet can be selectively decoupled from the primary cabinet and alternatively structurally supported using the accessory support system.

Abstract: An electrical power supply system includes a freestanding primary electrical unit, a non-freestanding accessory unit, and an accessory unit support system. The primary electrical unit includes a freestanding cabinet containing a primary electrical component. The accessory unit includes a non-freestanding accessory cabinet containing an accessory electrical component. The accessory unit support system is configured to couple the accessory cabinet to the primary cabinet such that the accessory unit is thereby structurally supported by the primary electrical unit. The accessory cabinet can be selectively decoupled from the primary cabinet and alternatively structurally supported using the accessory support system.

Abstract: An uninterruptible power supply (UPS) apparatus can include an uninterruptible power supply circuit configured to provide electrical power to a load corresponding to a loss of line power, a network communications interface circuit associated with the uninterruptible power supply circuit, configured to be coupled to a network and a self-identification circuit that determines network identifier availability responsive to communications on the network and assigns a determined available network identifier responsive to an identification enable signal. Methods of self-identification of a device in a network, include determining an identifier via a self-identification process responsive to a relative position in the network.

Abstract: An uninterruptible power supply (UPS) system includes an AC input configured to be coupled to an AC power source, an AC output configured to be coupled to a load, a power conversion circuit comprising a first converter circuit configured to receive power from a variably available power source, a second converter circuit coupled to the AC output, a DC link coupling the first and second converter circuits, and a switching circuit, e.g., a bypass circuit, configured to selectively couple and decouple the AC input and the AC output. The UPS system further includes a control circuit operatively associated with the power conversion circuit and the switching circuit and configured to cause concurrent transfer of power to a load at the AC output from the AC power source and the variably available power source via the switching circuit and the power conversion circuit, respectively.

Abstract: An uninterruptible power supply (UPS) system includes a power transfer circuit having a power output configured to be coupled to a load, a UPS circuit having first power input configured to be coupled to a generator, such as a diesel- or gas-powered engine-generator set. The UPS circuit also has a second power input configured to be coupled to a backup power source, such as a battery or other energy storage device. The UPS circuit further has a power output configured to be coupled in common to the load with the power output of the power transfer circuit. The UPS system further includes a control circuit operatively associated with the UPS circuit and configured to control provision of power to the load from the generator and the backup power source via the UPS circuit responsive to a status of the power transfer circuit. The power transfer circuit may include, for example, another UPS circuit or other power transfer device, such as a static switch.

Abstract: An uninterruptible power supply (UPS) system includes an AC input configured to be coupled to an AC power source, an AC output configured to be coupled to a load, a power conversion circuit comprising a first converter circuit configured to receive power from a variably available power source, a second converter circuit coupled to the AC output, a DC link coupling the first and second converter circuits, and a switching circuit, e.g., a bypass circuit, configured to selectively couple and decouple the AC input and the AC output. The UPS system further includes a control circuit operatively associated with the power conversion circuit and the switching circuit and configured to cause concurrent transfer of power to a load at the AC output from the AC power source and the variably available power source via the switching circuit and the power conversion circuit, respectively.

Abstract: Uninterruptible power supply (UPS) systems include an AC input configured to be coupled to an AC power source, an AC output configured to be coupled to a load and a UPS circuit including a first converter circuit coupled to the AC input, a second converter circuit coupled to the AC output and a DC bus coupling the first converter circuit to the second converter circuit. The system further includes a third converter circuit having an output coupled to the AC output and an input configured to receive power from a variably available power source and a control circuit operatively associated with the UPS circuit and the third converter circuit and configured to cooperatively control the UPS circuit and the third converter circuit to selectively transfer power to the load from the AC power source and the variably available power source.

Abstract: An uninterruptible power supply (UPS) of a UPS system including a plurality of UPSs connected in parallel at a load bus and configured to provide power thereto from respective batteries of a plurality of batteries is operated such that a difference between a variable, for example, battery voltage, indicative of battery capacity for a battery associated with the subject UPS and an average value of the variable for the plurality of batteries is determined and a power flow between the subject UPS and the load bus is controlled responsive to the determined difference. Controlling a power flow between the subject UPS and the load bus responsive to the determined difference may include, for example, controlling a phase of an inverter of the subject UPS responsive to the determined difference.

Abstract: An uninterruptible power supply (UPS) of a UPS system including a plurality of UPSs connected in parallel at a load bus and configured to provide power thereto from respective batteries of a plurality of batteries is operated such that a difference between a variable, for example, battery voltage, indicative of battery capacity for a battery associated with the subject UPS and an average value of the variable for the plurality of batteries is determined and a power flow between the subject UPS and the load bus is controlled responsive to the determined difference. Controlling a power flow between the subject UPS and the load bus responsive to the determined difference may include, for example, controlling a phase of an inverter of the subject I 0 UPS responsive to the determined difference.

Abstract: An apparatus can include a fault condition detector configured to detect a fault condition in an electrical system, a delta d-q power value generator configured to generate a delta d-q power value temporally corresponding to the detected fault condition, and a characterizer circuit configured to characterize the fault condition relative to the apparatus responsive to the delta d-q power value. Methods can include detecting a fault condition in an electrical system and determining changes in d-q component voltage and current temporally corresponding to the detected fault condition. Such methods can further include characterizing the fault condition responsive to the determined first and second changes and controlling an apparatus based on characterizing the fault condition.

Abstract: An uninterruptible power supply (UPS) apparatus can include an uninterruptible power supply circuit configured to provide electrical power to a load corresponding to a loss of line power, a network communications interface circuit associated with the uninterruptible power supply circuit, configured to be coupled to a network and a self-identification circuit that determines network identifier availability responsive to communications on the network and assigns a determined available network identifier responsive to an identification enable signal. Methods of self-identification of a device in a network, include determining an identifier via a self-identification process responsive to a relative position in the network.

Abstract: An apparatus can include a fault condition detector configured to detect a fault condition in an electrical system, a delta d-q power value generator configured to generate a delta d-q power value temporally corresponding to the detected fault condition, and a characterizer circuit configured to characterize the fault condition relative to the apparatus responsive to the delta d-q power value. Methods can include detecting a fault condition in an electrical system and determining changes in d-q component voltage and current temporally corresponding to the detected fault condition. Such methods can further include characterizing the fault condition responsive to the determined first and second changes and controlling an apparatus based on characterizing the fault condition.