Provided is a power converter capable of reducing cross current. The power converter 1 includes a phase controller 20 that calculate a phase angle reference value θm based on a difference between a commanded active power reference value Pe and an output active power P supplied to a distribution line 5, a voltage controller 10 that calculates a voltage reference values Vu, Vv, and Vw based on the phase angle reference value θm calculated by the phase controller 20, and a power conversion unit 52 that converts, based on the voltage reference values Vu, Vv, and Vw calculated by the voltage controller 10, an electric power supplied from a power supply source 60 into AC power and outputs it to the distribution line 5.

A mobile offshore drilling unit includes a plurality of electric thrusters to dynamically position the drilling unit, and a microgrid electric power generation system for providing power to the plurality of electric thrusters, the microgrid electric power generation system including at least one combustion generator electrically coupled to a main electric power bus and at least one thruster electric power system, the thruster electric power system including a thruster electric power bus, an additional electric power bus connected to the thruster electric power bus via an interface device, and a circuit breaker electrically coupling the additional electric power bus to a main electric power bus for isolating the thruster electric power bus from the main electric power bus in case of loss of power on the main electric power bus.

A method for stabilizing a DC voltage in a DC grid that includes a DC bus connected to a higher-order grid and to which an energy generating system and at least one load are connected. A variable electric grid output is exchanged between the DC bus and the higher-order grid in order to keep the DC voltage in the DC bus at a nominal voltage. The energy generating system includes a PV generator connected to the DC bus via a DC-to-DC converter and which exchanges an electric generator output with the DC bus. In a normal operating mode, the generator output is set to a normal operating output by the DC-to-DC converter on the basis of an MPP output of the PV generator. In a grid support mode, the generator output is set to a grid support output on the basis of the DC voltage in the DC bus in order to counteract a power imbalance between the electric power supplied in total to the DC bus and the power drawn in total from the DC bus.

Various embodiments include a method for controlling an energy exchange among a plurality of energy systems using a control center, wherein a component of one of the plurality of energy systems is coupled to the control center via an interface module for data exchange. The method includes: transmitting a first data set to the interface module with a prediction profile regarding an energy exchange of the component; transmitting a second data set to the control center using the interface module including the first data set and component-specific data of the component; determining control data using the control center using the prediction profile and the component-specific data and data communicated to the control center by further energy systems to determine the control data; transmitting the determined control data to the interface module; and operating the component based on the control data.

The present disclosure provides a system-level protection system and method for sub/super-synchronous resonance/oscillation. The system includes a centralized protection coordinator arranged in a control center and a plurality of distributed protection relays arranged in a plurality of transformer substations or wind farms. Each distributed protection relay is configured to acquire a sub/super-synchronous impedance of the wind farm. The centralized protection coordinator is configured to acquire the sub/super-synchronous impedances measured by the plurality of distributed protection relays, to obtain a sub/super-synchronous aggregate impedance of the system according to a preset circuit topology and the sub/super-synchronous impedances, and to generate a system-level protection signal when the sub/super-synchronous aggregate impedance does not meet a stable condition. Each distributed protection relay is further configured to initiate a system-level protection according to the system-level protection signal.

A charging station for providing power to a physiological monitoring device can include a charging bay and a tray. The charging bay can include a charging port configured to receive power from a power source. The tray can be positioned within and movably mounted relative to the charging bay. The tray can be further configured to secure the physiological monitoring device and move between a first position and a second position. In the first position, the tray can be spaced away from the charging port, and, in the second position, the tray can be positioned proximate the charging port, thereby allowing the physiological monitoring device to electrically connect to the charging port.

A microgrid system includes first and second DC power sources electrically connected to respective first and second DC electrical power busses, a first uninterruptable power module electrically connected to the first DC electrical power bus and configured to be connected to an alternating current (AC) load, a second uninterruptable power module electrically connected to the second DC electrical power bus and configured to be connected to the AC load, a first bi-directional AC/DC inverter having a DC end and an AC end, where the first DC electrical power bus is connected to the DC end of the first bi-directional AC/DC inverter, a second bi-directional AC/DC inverter having DC and AC ends, where the second DC electrical power bus is connected to the DC end of the second bi-directional AC/DC inverter, and an AC electrical power bus electrically connected to the first and second bi-directional AC/DC inverters at their AC ends.

A technique enables microgrid switchover using zero cross detection. A flexible load management system includes a virtual critical load panel (vCLP) that utilizes circuit breakers in combination with companion modules configured to sense power provided to one or more loads to identify zero-crossings. When a preconfigured number of consecutive, missed zero-crossings is detected, the companion module is alerted as to potential main power loss and transitions to a virtual critical load (vCL) mode for load adjustment prior to operation under local power. Upon detection of main power loss, the companion module is configured for load activation (or deactivation) via states of one or more vCL bits that configure each load for either ON or OFF state when operating under local power.

A system and method for controlling a number of load controllers (10), each of which is operatively connected to one or more electrical loads (6) that are connected to a grid, results in a reduction in tracking errors, which arise when aggregated local devices fail to deliver the expected amount of responsive load service. Each load controller (10) monitors the operating frequency of the grid network (8) and is adapted to adjust power consumption of one or more of its electrical loads (6) in response to excursions of the operating network frequency from its nominal value. The load controllers (10) are in communication with a remote controller (14) and aggregated together to provide a responsive load service. The remote controller (14) is adapted to monitor the deviation of grid frequency from its nominal value and to determine adjustments to the responsive load service delivered by the electrical loads of each load controller. The remote controller (14) thereafter sends a correction signal to each load controller (10), which causes the respective load controller (10) to apply a correction to its responsive load service by way of an offset to its power consumption adjustments.

An asset manager controls power distribution within an aggregated distributed energy resources system (“DERs system”) having a plurality of assets. The asset manager is configured to operate with a given asset. As such, the asset manager has 1) an interface to receive asset information relating to the given asset and to communicate with another asset manager in the DERs system, and 2) a function generator configured to produce a local cost function using data relating to the given asset only. The local cost function represents a portion of a system cost function for the DERs system. The asset manager also has 3) a controller configured to use the local cost function for the given asset to manage operation of the given asset in the DERs system. In addition, the controller also is configured to determine, using the local cost function, an operating point for the given asset.