Abstract: Systems and methods for controlling an energy storage system are provided. In one embodiment, a method for controlling an energy storage system includes receiving a power demand associated with a grid service operation for an energy storage system and accessing data indicative of a time shift for responding to the power demand. The method includes implementing the time shift in the power demand to obtain a time shifted power demand; and controlling the charge or discharge of one or more energy storage devices in the energy storage system based at least in part on the time shifted power demand.

Abstract: The present disclosure is directed to a system and method for calibrating state-of-charge (SOC) of an energy storage device. The method includes monitoring, via a battery management system, at least one of an accumulated capacity of the energy storage device after a first SOC calibration or a time period after the first SOC calibration. Another step includes determining, via the battery management system, whether at least one of the accumulated capacity or the time period is above a predetermined threshold. If at least one of the accumulated capacity or the time period is above a predetermined threshold, then the method includes charging, via the battery management system, the energy storage device for a specified duration until the energy storage device reaches a second SOC calibration.

Abstract: Systems and methods for charging a plurality of battery strings are provided. The individual string current of each of the individual battery strings can be monitored and used to regulate a charging output provided by the charger. For instance, the output voltage of charger can be controlled as part of a closed loop control system based on the individual string current of the battery string under the constraint of an individual string current limit and/or a charging voltage limit. As the charging voltage of the charger increases as a result of the closed loop control based on the individual string current, other battery strings can be coupled to the charger when the charging voltage provided by the charger exceeds a battery string voltage associated with the battery string.

Abstract: Systems and methods for controlling power distribution are provided. The method includes receiving a power command, wherein the power command requests a discharge from one or more BESS units, and wherein the one or more BESS units are housed in one or more temperature controlled rooms. For each of the one or more temperature controlled rooms, a lowest energy remaining of the one or more BESS units in the temperature controlled room is determined; a low threshold is determined based on the determined lowest energy remaining and a floor; a limit is determined based on the determined low threshold; and the limit is assigned to each of the one or more BESS units housed in the temperature controlled room. The method includes causing the power command to be at least partially satisfied by the one or more BESS units based on the assigned limits.

Abstract: The present disclosure is directed to a system and method for controlling an energy storage device by more accurately detecting an end-of-discharge voltage of the energy storage device. More specifically, in one embodiment, the method includes determining an end-of-discharge voltage threshold for the energy storage device. Another step includes filtering the end-of-discharge voltage threshold via a filter. The method also includes adjusting a time constant of the filter based on at least one voltage-current condition. Still a further step includes comparing the filtered end-of-discharge voltage threshold and a terminal voltage of the energy storage device. Based on the comparison, the method includes determining a change of state of the energy storage device. Thus, the energy storage device can be controlled based on the change of state.

Abstract: Systems and methods for controlling power distribution are provided. The method includes receiving a power command, wherein the power command requests a discharge from one or more BESS units, and wherein the one or more BESS units are housed in one or more temperature controlled rooms. For each of the one or more temperature controlled rooms, a lowest energy remaining of the one or more BESS units in the temperature controlled room is determined; a low threshold is determined based on the determined lowest energy remaining and a floor; a limit is determined based on the determined low threshold; and the limit is assigned to each of the one or more BESS units housed in the temperature controlled room. The method includes causing the power command to be at least partially satisfied by the one or more BESS units based on the assigned limits.

Abstract: Systems and methods for charging a plurality of battery strings are provided. The individual string current of each of the individual battery strings can be monitored and used to regulate a charging output provided by the charger. For instance, the output voltage of charger can be controlled as part of a closed loop control system based on the individual string current of the battery string under the constraint of an individual string current limit and/or a charging voltage limit. As the charging voltage of the charger increases as a result of the closed loop control based on the individual string current, other battery strings can be coupled to the charger when the charging voltage provided by the charger exceeds a battery string voltage associated with the battery string.

Abstract: Systems and methods for controlling an energy storage system are provided. In one embodiment, a method for controlling an energy storage system includes receiving a power demand associated with a grid service operation for an energy storage system and accessing data indicative of a time shift for responding to the power demand. The method includes implementing the time shift in the power demand to obtain a time shifted power demand; and controlling the charge or discharge of one or more energy storage devices in the energy storage system based at least in part on the time shifted power demand.

Abstract: Systems and methods for charging a plurality of battery strings are provided. The individual string current of each of the individual battery strings can be monitored and used to regulate a charging output provided by the charger. For instance, the output voltage of charger can be controlled as part of a closed loop control system based on the individual string current of the battery string under the constraint of an individual string current limit and/or a charging voltage limit. As the charging voltage of the charger increases as a result of the closed loop control based on the individual string current, other battery strings can be coupled to the charger when the charging voltage provided by the charger exceeds a battery string voltage associated with the battery string.

Abstract: The present disclosure is directed to a system and method for controlling an energy storage device by more accurately detecting an end-of-discharge voltage of the energy storage device. More specifically, in one embodiment, the method includes determining an end-of-discharge voltage threshold for the energy storage device. Another step includes filtering the end-of-discharge voltage threshold via a filter. The method also includes adjusting a time constant of the filter based on at least one voltage-current condition. Still a further step includes comparing the filtered end-of-discharge voltage threshold and a terminal voltage of the energy storage device. Based on the comparison, the method includes determining a change of state of the energy storage device. Thus, the energy storage device can be controlled based on the change of state.

Abstract: Systems and methods for charging a plurality of battery strings are provided. The individual string current of each of the individual battery strings can be monitored and used to regulate a charging output provided by the charger. For instance, the output voltage of charger can be controlled as part of a closed loop control system based on the individual string current of the battery string under the constraint of an individual string current limit and/or a charging voltage limit. As the charging voltage of the charger increases as a result of the closed loop control based on the individual string current, other battery strings can be coupled to the charger when the charging voltage provided by the charger exceeds a battery string voltage associated with the battery string.

Abstract: The present disclosure is directed to a system and method for calibrating state-of-charge (SOC) of an energy storage device. The method includes monitoring, via a battery management system, at least one of an accumulated capacity of the energy storage device after a first SOC calibration or a time period after the first SOC calibration. Another step includes determining, via the battery management system, whether at least one of the accumulated capacity or the time period is above a predetermined threshold. If at least one of the accumulated capacity or the time period is above a predetermined threshold, then the method includes charging, via the battery management system, the energy storage device for a specified duration until the energy storage device reaches a second SOC calibration.

Abstract: A RF current transformer sensor includes a first sensor portion and a second sensor portion. The first and second sensor portions are configured to define a fixed opening for receiving a test object. The RF current transformer sensor is capable of detecting current pulses between the first sensor portion and the second sensor portion for sensing partial discharges from the test object. Further disclosed is a method of partial discharge sensing.

Abstract: A RF current transformer sensor includes a first sensor portion and a second sensor portion. The first and second sensor portions are configured to define a fixed opening for receiving a test object. The RF current transformer sensor is capable of detecting current pulses between the first sensor portion and the second sensor portion for sensing partial discharges from the test object. Further disclosed is a method of partial discharge sensing.

Abstract: A partial discharge sensing system and method for conducting testing inside an enclosure includes a partial discharge sensor, an access port, and a signal cable. The partial discharge sensor is permanently installed at a test location inside the enclosure. The access port is configured so that an analyzer can be connected to the access port from an exterior of the enclosure. The signal cable operably connects the partial discharge sensor and the access port to enable an analyzer connected to the access port from outside the enclosure to interface with the partial discharge sensor for generating test data.

Abstract: A partial discharge sensing system and method for conducting testing inside an enclosure includes a partial discharge sensor, an access port, and a signal cable. The partial discharge sensor is permanently installed at a test location inside the enclosure. The access port is configured so that an analyzer can be connected to the access port from an exterior of the enclosure. The signal cable operably connects the partial discharge sensor and the access port to enable an analyzer connected to the access port from outside the enclosure to interface with the partial discharge sensor for generating test data.