The present disclosure provides a switch circuit and a control method thereof, a smart switch and a control system. The switch circuit includes a wireless communication module, a switch module coupled to a load, a switch-on power obtaining circuit, an energy storage circuit coupled with the wireless communication module and a switch-off power obtaining circuit. The load is coupled with a neutral wire. The switch-on power obtaining circuit is configured to output a first current to the energy storage circuit in response to the switch module being switched on. The switch-off power obtaining circuit is configured to output a second current to the energy storage circuit via the second power supply terminal in response to the switch module being switched off. The second current is less than the first current.

A remotely controlled switching module that provides switching and preferably dimming functions for one or more AC or DC power distribution lines. The inventive module is preferably sized to fit within existing outlet and switch boxes, while still leaving enough room for the conventional components that are also housed in such enclosures. Remote control is provided wirelessly—preferably using an existing wireless communication protocol. Local control is preferably also provided for the inventive switching module. Local control inputs preferably allow control via existing components—such as two-pole light switches.

Embodiments of present disclosure relates to a modular interconnection device (MID) and an electrical network system. The MID comprises a modular port assembly, a node, a converter and a local controller. The modular port assembly is configured to transmit alternating current and/or direct current. The node is coupled to an AC source via a first switch and the modular port assembly. The first switch is configured to selectively disconnect the modular interconnection device from the AC source. The converter is coupled to the node via a second switch and coupled to a DC source via a third switch. The converter is configured to convert the AC current into DC current or convert DC current into AC current. The local controller is coupled to the first, second and third switches and configured to control operation of the first, second and third switches.

A micro grid system comprises an adapter, a power controller, and secondary energy source. The adapter is in communication with an electric grid and configured to connect and disconnect a connection between the electric grid and a micro grid. The power controller is in communication with the adapter and configured to receive first AC power from the electric grid via the adapter, obtain grid information, and control the adapter to connect and disconnect the connection between the electric grid and the micro grid. The power controller controls the adapter to disconnect the connection in response to determining that the electric grid is abnormal based on the grid information. The secondary energy source is in communication with the power controller and is configured to generate DC power and to supply the DC power to the power controller.

A pathogen sterilization light assembly for a vehicle cabin is provided herein and may include a plurality of sterilization lights mounted spaced apart along a cabin of the vehicle and configured to emit ultraviolet (UV) light directed toward areas within the cabin to sterilize pathogens.

An artificial intelligence reactive power control system for low voltage ride-through in a grid connected distributed generation network includes a grid, a circuit breaker, a distributed generation circuit including 3-phase terminals, and a voltage and current measurement unit connected to the 3-phase terminals and configured to generate a set of measured variables. An intelligent low voltage ride-through detector receives the set of measured variables and identifies a low voltage ride-through status of the utility grid. An intelligent reactive power controller receives a low voltage ride-through status signal from the intelligent low voltage ride-through detector and controls a low voltage ride-through during a grid voltage sag and a voltage reduction by transmitting one or more of an active power reference and a reactive power reference value to the distributed generation circuit based on the low voltage ride-through status signal.

Certain embodiments of the present application relate to a variable frequency drive (VFD) cabin for a pump configuration including a mobile trailer on which the VFD cabin is to be mounted. The VFD cabin generally includes a medium-voltage VFD and a ventilation system. In certain embodiments, the ventilation system is configured to generate an overpressure condition within the cabin to discourage the entry of dust and debris into the cabin. In certain embodiments, one or more components of the medium-voltage VFD are coupled to the floor of the cabin via a vibration damping system. In certain embodiments, the VFD cabin may be directly coupled to a chassis of the mobile trailer without an intervening suspension being provided between the VFD cabin and the chassis.

A method and device for load shedding in an electrical power system is provided. The electrical power system includes a device that electrically couples one or more load feeder lines to the electrical power system, where each load feeder lines provides power to consumers. The method includes: monitoring the electrical frequency of the electrical power system and monitoring a frequency stability parameter, which is dependent on a rate of change of the electrical frequency. A control signal is generated to disconnect at least one load feeder line by the device when the monitored frequency is at or below at least a predetermined disconnection frequency threshold and the monitored frequency stability parameter is at or has passed at least one predetermined frequency stability parameter threshold.

Certain embodiments of the present application relate to a variable frequency drive (VFD) cabin for a pump configuration including a mobile trailer on which the VFD cabin is to be mounted. The VFD cabin generally includes a medium-voltage VFD and a ventilation system. In certain embodiments, the ventilation system is configured to generate an overpressure condition within the cabin to discourage the entry of dust and debris into the cabin. In certain embodiments, one or more components of the medium-voltage VFD are coupled to the floor of the cabin via a vibration damping system. In certain embodiments, the VFD cabin may be directly coupled to a chassis of the mobile trailer without an intervening suspension being provided between the VFD cabin and the chassis.

Systems and methods for verifying correct completion of a power control sequence in a switchgear provide a commissioning agent that can automatically verify correct completion of the power control sequence. The commissioning agent includes a sequence verification tool that can initiate performance of a power control sequence in the switchgear and immediately compare the sequence actually performed to the sequence intended to be performed. If the two sequences do not match in order and timing, the verification tool reports the mismatch and identifies the error. In some embodiments, the commissioning agent further includes a log viewer that captures the sequence actually performed in the switchgear and displays the result for viewing. Such an arrangement provides a faster and more reliable way to double-check the system integrity of the switchgear during initial engineering and after factory and/or field modifications.