A direct current circuit breaker includes main circuit for carrying a main-path current, and a transient circuit for carrying a transient-path current. The main circuit includes a first solid state switch and a main contactor. The first solid state switch is coupled in series with the main contactor. The transient circuit is coupled in parallel with the main circuit. The transient circuit includes an auxiliary contactor coupled in series with a second solid state switch. The second solid state switch closes when the main-path current exceeds a first threshold. The first solid state switch then opens. The main contactor opens when the main-path current falls below a second threshold. Then the second solid state switch opens. The auxiliary contactor opens when the transient-path current falls below the second threshold and after the second solid state switch opens.

A circuit breaker with a switching path has at least one line interruption apparatus, wherein the circuit breaker has a disconnection unit and a connection unit which are each connected to the line interruption apparatus. The switching device has at least one measuring arrangement for measuring at least one electrical variable on the at least one switching path. The disconnection unit further has a comparison and decision unit, which comparison and decision unit is connected to the measuring arrangement and to the line interruption apparatus. The circuit breaker has a first data interface, which first data interface is designed to receive at least one connection command and/or one disconnection command, and wherein the first data interface is connected to the disconnection unit and the connection unit.

An active inrush current limiter and method of limiting inrush current actively monitor line voltage and voltage drop across a current limiting resistance in a manner that eliminates the impact of fluctuations of line voltage on the decision of when to close a relay and bypass a current limiting resistance between the AC source and a group of power supplies. The active inrush current limiter includes a microcontroller connected to control the electronic switch and relay. The microcontroller is configured to sample the source AC power and detect a pattern of current flow through the electronic switch and current limiting resistance. A program executed in the microcontroller includes calculations that determine when to close the relay and bypass the current limiting resistance by detecting changes in power flow through the current limiting resistance that reliably correspond to a time when the capacitors in the power supplies have completed charging.

Electrostatic discharge clamp devices are described. In one embodiment, the semiconductor device includes a first transistor, the first transistor including a first source/drain and a second source/drain, the first source/drain coupled to a first potential node, the second source/drain coupled to a second potential node. The device further includes a OR logic block, a first input of the OR logic block coupled to the first potential node through a capacitor, the first input of the OR logic block being coupled to the second potential node through a resistor, and a second input of the OR logic block coupled to a substrate pickup node of the first transistor.

An electro-static discharge (ESD) protection circuit utilizes a gate-drain breakdown characteristic of high electron mobility transistors (HEMTs) in a dual stacked configuration to provide a discharge path for electro-static discharges, while having a minimal effect on the associated circuit which is being protected.

Embodiments described herein are directed to inrush current limiters having a transformer. In one embodiment, an inrush current limiter includes a transformer including a primary winding, a secondary winding and a saturable magnetic core shared therebetween, a resistor connected in parallel with the secondary winding, wherein an impedance of the resistor is reflected across the transformer when a voltage is applied across the primary winding and the saturable magnetic core is not saturated, and a diode connected between the primary winding and ground.

A current electronic distributing device that can limit maximum output currents of a plurality of input/output (I/O) ports to a first current or a second current. The current electronic distributing device includes a plurality of current detection units, a plurality of current limiting units, a control unit, and a power supply unit. The power supply unit supplies power to the current electronic distributing device. Each of the current detection units respectively detects consumption currents of each of the I/O ports. The control unit calculates a sum of the consumption currents of the plurality of I/O ports, and controls each of the current limiting units to limit the maximum output currents of each of the I/O ports to the first current or the second current according to the sum of the consumption currents of the plurality of I/O ports.

An IC, comprising a first rail supply, a second rail supply, an external pad coupled to one of the first rail supply and the second rail supply, and an ESD protection circuit coupled to the external pad. The ESD protection circuit includes a slew rate detector coupled to the external pad, an amplifier coupled to an output of the slew rate detector, a one-shot coupled to an output of the amplifier, and a clamp circuit coupled an output of the one-shot.

The present invention is concerned with pre-magnetizing a Modular Multilevel power Converters connected transformer in order to moderate inrush currents upon connecting the transformer to an electric grid. The invention takes advantage of the high amount of stored energy in MMC converters as compared to other converter types. This stored energy is used to pre-magnetize the converter-connected transformer, therefore no additional or dedicated pre-magnetizing hardware is required in addition to the charging hardware provided to charge the converter capacitors. As the transformer pre-magnetizing takes place subsequent to the converter charging, the converter charging circuit is not used to, and therefore does not need to be designed to, directly magnetize the transformer.

An AC switching arrangement is provided with an energy transfer arrangement connected in parallel with a switching mechanism. The energy transfer arrangement comprises a capacitance arrangement and a diode arrangement. The switching mechanism normally closed in a first state, and on reception of a signal indicating the second state, the switching mechanism is arranged to open. When the switching mechanism is in the second state, the diode arrangement is arranged in each AC half cycle to enable energy (source energy, stored inductance energy, etc.) to transfer from the grid to the capacitance arrangement but to prevent energy transfer from the capacitance arrangement back to the grid.