A miniature circuit breaker for providing short circuit and overload protection is disclosed herein. The miniature circuit breaker features a field effect transistor (FET), which may be a depletion mode metal oxide semiconductor FET (D MOSFET), a junction field-effect transistor (JFET), or a silicon carbide JFET, the FET being connected to a bi-metallic switch, where the bi-metallic switch acts as a temperature sensing circuit breaker. In combination, the D MOSFET and bi-metallic switch are able to limit current to downstream circuit components, thus protecting the components from damage.

A method of operating a Fault Current Limiter Circuit Breaker including a plurality of FLCB modules connected in series, including at least a first module and a second module. Each module includes a plurality of parallel component legs including a mechanical switch leg including a mechanical switch, a semiconductor switch leg including a semiconductor switch, and a Metal Oxide Varistor leg including a MOV. The method includes, when the FLBC is in an open configuration, obtaining an indication that the FLCB should be closed; in response to the obtained indication, closing the semiconductor switch of each of the modules; and, after the closing of the semiconductor switches and while the mechanical switch of the second module remains open, closing the mechanical switch of the first module.

A system is disclosed which eliminates problems caused by surges of electric energy which is generated on a utility customer's property and which is fed back onto a utility-owned service line by maintaining a minimum utility provided percentage (MUPP) of power being provided onto a customer-owned dead-end service line. Where the electric energy generated by a utility customer is incrementally excluded from the customer-owned dead-end service line through a plurality of contactors which are controlled by a 120 volt command line.

Provided are a protection circuit and a photovoltaic system capable of irreversibly interrupting a current path of photovoltaic units such as solar cells by a signal in an emergency such as a fire. The protection circuit includes: a photovoltaic units 26, a protection element 2 provided on a current path of the photovoltaic units 26, and a switch 3 for activating the protection element 2, wherein the protection element 2 irreversibly interrupts the current path of the photovoltaic units 26.

A current interrupting device includes a current limiting element on a power supply path from a predetermined power supply to a load device. The current limiting element is configured to exhibit a current limiting action when current flowing in the power supply path exceeds a first current threshold value. The current interrupting device further includes a current diversion path switch, and a controller programmed to control on and off of the current diversion path switch. The controller is programmed to switch a current diversion path switch on from an off state when it is detected that current flowing in the current limiting element is limited to a second current threshold value after the current flowing in the current limiting element has exceeded the first current threshold value, and switch the switch off again after a predetermined switched-on holding time has elapsed since the switch has been switched on.

The present invention provides a system and computer program product for implementing a smart transformer, comprising a processor, and a balancing algorithm residing on the processor, wherein the balancing algorithm is stored on a non-transitory computer readable medium having computer executable program code embodied thereon, the computer executable program code configured to cause the system to monitor and control an electric customer load and generation in order to optimize the performance of a distribution transformer, wherein the processor receives a plurality of system inputs and uses the balancing algorithm to determine a rating of the transformer and an amount of customer load.

A control device for connecting between two portions of an electrical power supply line. The device includes a bipolar transistor including a wide bandgap semiconductor material and having its emitter connected to one portion of the power supply line, its collector connected to another portion of the power supply line, and the device also including control connected to the base of the transistor.

A DC electrical network comprising DC terminals operatively connectable to a converter; and DC transmission paths arranged to interconnect the DC terminals, and including a DC power transmission medium and a switching apparatus. The DC network further including: an active power electronic device connected in at the DC transmission paths, the active power electronic device; a detector configured to detect faults in the DC transmission paths; and a control unit programmed to operate the active power electronic device to vary an apparent impedance of a faulty DC transmission path to force a current flowing in the faulty DC transmission path to reduce to a target current level, and operate the switching apparatus to block current from flowing in the faulty DC transmission path when the current flowing in the faulty corresponding DC transmission path is reduced to the target current level.

A solid-state zero current switching circuit breaker is configured to interrupt current flow between a voltage input and a load. The solid-state zero current switching circuit breaker includes at least one resonant capacitor cell having an input configured to receive a source voltage and an output configured to deliver drive current to the load. The resonant capacitor cell is configured to selectively limit the drive current to the output based on a variable voltage. The solid-state zero current switching circuit breaker further includes at least one voltage clamping switch configured to detect a short-circuit fault or an overload condition. The voltage clamping switch adjusts the variable voltage in response to detecting the short-circuit fault condition or the overload condition such that the resonant capacitor cell limits the drive current.

A fault clearing circuitry provided for connecting to at least one electrical line transmitting power includes: an electrical energy storage; at least one controllable switch connectable between the electrical energy storage and at least one electric line; and a control circuit for monitoring the at least one electric line for a fault and to close the at least one controllable switch if a fault is detected. The electrical energy storage stores an amount of electrical energy dimensioned to be sufficient for releasing one or more circuit breakers or clearing one or more fuses in the at least one electrical line in order to clear the fault. The control circuit closes the at least one controllable switch if a fault is detected such that a discharging of the electrical energy stored in the electrical energy storage is incurred injecting a current pulse in the at least one electrical line.