Abstract: A disconnecting device for interrupting the direct current between a direct current source, in particular in the direct voltage range between 300 VDc and/or in the nominal current range between 4A and 250A, and a load. The device has at least one protection switch with a protection switch arrangement having a magnetic trigger, and has semiconductor electronics which are connected in parallel to the at least one protection switch and which block the current when the protection switch arrangement is in a current-conducting state and which conducts current at least temporarily when the protection switch arrangement is triggered. A current, in particular an electric arc current generated as a result of an electric arc, is switched, when the protection switch arrangement is triggered, from the at least one protection switch to the semiconductor electronics.

Abstract: An electrical protection unit A including a main conductor and, for each main conductor, a current limiter device connected in series with the main conductor to limit the current when a current or temperature threshold is exceeded, the limiter device including an element made of a material having a positive temperature coefficient, called PTC, and being capable of controlling a device for tripping the mechanism M for opening the contacts of the protection unit D, to cause the opening of the contacts of the unit when the threshold is exceeded leading to a change of state of the element between a low resistance state and a high resistance state. The PTC element includes the trip device, in such a way that this element itself provides the functions of fault current limitation and of tripping the mechanism for opening the contacts.

Abstract: An interrupter device for interrupting a direct current between a direct current source and an electrical device, for example, between a photovoltaic generator and an inverter. The interrupter device has a mechanical switch which has a first fixed contact, a second fixed contact, and a contact bridge that can be moved between a first position and a second position. The contact bridge and the first fixed contact are electrically contacted to a semiconductor switch which blocks a current when the contact bridge is in the first position. A control input of the semiconductor switch is connected to the mechanical switch such that an arc voltage generated as a result of an arc across the switch connects the semiconductor switch so as to conduct a current when the contact bridge is moved into the second position.

Abstract: Integrated circuits with electrostatic discharge (ESD) protection and methods of providing ESD protection in an integrated circuit are provided. An ESD protection circuit the ESD protection circuit may incorporate a transistor, such as a MOSFET, and a voltage limiter coupled to a gate of the transistor. The voltage limiter may be configured such that with an ESD disturbance on the voltage supply rail, Vdd, a gate voltage of the transistor of the ESD protection circuit is held below the supply voltage (Vdd) inducing base current, Isub, within the transistor to effectively shunt a current arising from the ESD event from the voltage supply rail Vdd to the voltage supply rail Vss.

Abstract: A device for switching a direct current includes an operating current path which has a mechanical switch, a switch-off current path which is connected in parallel to the operating current path and has a power-electronic switch, and a commutation device which allows commutation of the direct current from the operating current path into the switch-off current path. The commutation device includes a transformer.

Abstract: The present invention relates to a high-voltage direct current (DC) circuit breaker for cutting off a fault current from flowing through a line during a malfunction in a high-voltage DC line. A DC circuit breaker according to the present invention comprises: a mechanical switch disposed on a DC line; an L/C circuit connected in parallel with the mechanical switch (110), and comprising a capacitor and a reactor connected in series to each other to generate LC resonance; a first semiconductor switch, connected in parallel to the L/C circuit, for switching the unidirectional flow of the current; and a second semiconductor switch, connected in parallel to the first semiconductor switch, for switching the uni- and reverse-directional flow of current.

Abstract: Some embodiments of the present disclosure relate to a direct current circuit breaker capable of shortening a cut-off operation time and reducing a magnitude of a required reverse current. The direct current circuit breaker includes: a main circuit line which is connected between a power supply and a load, the main circuit line includes a main breaker and a first diode connected in parallel; a charging circuit line which is disposed in the rear stage of the main breaker and is connected in parallel to the load, the charging circuit line includes a first capacitor, a reactor and a second diode connected in series; and a switch line including one end connected in parallel to the front stage of the main breaker and the other end connected between the reactor and the second diode, the switch line includes a third diode and a current switch connected in series.

Abstract: A method of and apparatus for protecting a MEMS switch is provided. The method and apparatus improve the integrity of MEMS switches by reducing their vulnerability to current flow through them during switching of the MEMS switch between on and off or vice versa. The protection circuit provides for a parallel path, known as a shunt, around the MEMS component. However, components within the shunt circuit can themselves be removed from the shunt when they are not required. This improves the electrical performance of the shunt when the switch is supposed to be in an off state.

Abstract: A circuit interrupter including a ground fault circuit interrupter circuit structured to detect a ground fault based on current flowing in line and neutral conductors of the circuit interrupter, a ground fault circuit interrupter monitor circuit structured to perform a self-test on the circuit interrupter to determine the functional status of the ground fault circuit interrupter, and a bridge circuit structured to harvest power from the line and neutral conductors and supply said harvested power to the ground fault circuit interrupter circuit and the ground fault circuit interrupter monitor circuit.

Abstract: A solid-state circuit breaker for a DC power system which may operate unidirectional and bidirectional and does not require an external power supply to provide current interruption protection during an event of a short circuit fault.

Abstract: A voltage monitoring test circuit includes a switching control signal generation unit configured to receive first and second switching signals, control the first and second switching signals such that an enable period of the first switching signal and an enable period of the second switching signal do not overlap with each other, and generate first and second switching control signals where a first voltage is transmitted in response to the first switching control signal and a second voltage is transmitted in response to the second switching control signal.

Abstract: Embodiments are directed to a discrete input circuit comprising: a switch, a capacitor coupled to the switch, a first resistor connected in series with the capacitor and coupled to a power supply, and a second resistor coupled to the power supply and the switch, wherein a value of the capacitor, a value of the first resistor, and a value of the second resistor are selected to provide a wetting current from the power supply to the switch when the switch is closed in order to clean contacts associated with the switch.

Abstract: A shutdown apparatus and method for use in conjunction with automatic test equipment (ATE) is provided. A unit under test (UUT) is inserted into an ATE receiver that couples the UUT to at least one electronic device during test and extracted from the ATE receiver after test. The shutdown apparatus comprises an electro-mechanical interface that inserts the UUT into the receiver prior to test and extracts the UUT from the receiver after test A shutdown module is coupled to the electronic device and to the electro-mechanical interface and connects the electronic device to the receiver after insertion of the UUT into the receiver and disconnects the electronic device from the receiver prior to extraction of the UUT from the receiver.

Abstract: A high voltage surge arrester, including a varistor element arranged so as to be connected to a high voltage source and to carry a high voltage when being positioned in its operative position, and an electric insulator that encloses and is in contact with the varistor element and forms an outer surface of the apparatus, wherein the electric insulator includes a silicone-based rubber. The silicone based rubber includes particles chosen from the group consisting of Al2O3, BN and ZnO, to such an extent that the thermal conductivity of the silicone-based rubber is equal to or above 0.8 W/mK.

Abstract: An arrester for preventing an insulator supporting a power line from experiencing an electrical flashover comprises an electrode, a varistor, and a separating device. The electrode is spaced apart from the power line or a conductor that is electrically tied to the power line so as to define an external gap therebetween. The separating device, in turn, comprises two portions operative to separate from one another when the varistor experiences an electrical condition sufficient to cause the varistor to fail. The electrode, the external gap, the separating device, and the varistor are arranged in electrical series with one another and in electrical parallel with the insulator.

Abstract: A hybrid circuit breaker, including a first circuit that includes: a main current path which includes a mechanical switch element, a commutation path arranged in parallel with the main current path and including a controllable semi-conductor switch element. The breaker also includes a first capacitor provided in the commutation path in series with the controllable semi-conductor switch element, and a second circuit, arranged in series with the first circuit and including a second capacitor and an inductance-generating element arranged in series with each other.

Abstract: A quench propagation arrangement for a superconducting magnet comprising a plurality of series-connected superconducting coils, the arrangement comprising: a positive supply line connected to cathodes of first diodes, of which respective anodes are connected to each respective node of the series connection of superconducting coils; a negative supply line connected to anodes of second diodes, of which respective cathodes are connected to each respective node of the series connection of superconducting coils; a number of heaters, respectively thermally connected to each of the superconducting coils and electrically connected between the positive supply line and the negative supply line; and a voltage limiter connected between the positive supply line and the negative supply line, in parallel with the heaters.

Abstract: An apparatus, such as a switch module, is provided. The apparatus can include an electromechanical switch structure configured to move between an open configuration and a fully-closed configuration (associated with a minimum characteristic resistance) over a characteristic time. A commutation circuit can be connected in parallel with the electromechanical switch structure, and can include a balanced diode bridge configured to suppress arc formation between contacts of the electromechanical switch structure and a pulse circuit including a pulse capacitor configured to form a pulse signal (in connection with a switching event of the electromechanical switch structure) for causing flow of a pulse current through the balanced diode bridge. The electromechanical switch structure and the balanced diode bridge can be disposed such that a total inductance associated with the commutation circuit is less than or equal to a product of the characteristic time and the minimum characteristic resistance.

Abstract: A motor drive circuit comprises positive and negative input terminals for connection of the motor circuit to a DC supply, a DC link filter connected between the input terminals: an electric motor having at least two phases, a plurality of motor drive sub-circuits, each connected to a respective phase of the electric motor and which each control the flow of current into or out of the respective phase of the motor that has been drawn from the supply through the DC link filter, and a switching means provided in the electrical path between the DC link filter and the electric motor drive sub-circuits, the switching means being movable between a closed position in which it connects the DC link filter to the motor drive sub-circuits, and an open position which isolates the DC link filter from the motor drive sub-circuits.

Abstract: A DC noise absorbing device for preventing surges and regulating voltages includes a surge inhibitor, a fuse wire, a plurality of diodes, a plurality of Zener diodes, a plurality of diode alternate current switches (DIACs), a plurality of capacitors, and a circuit for indicating light emission, all of which are disposed on or between two wires respectively of positive voltage and negative voltage. The surge inhibitor and the fuse wire are connected in series on the wire of positive voltage; the plurality of diodes, the plurality of Zener diodes, the plurality of DIACs, the plurality of capacitors, which are identically specified, and the circuit for indicating light emission are orderly connected in parallel between the wires of positive voltage and negative voltage so as to form a staircase arrangement of cut-in switching voltages.

Abstract: In an actively triggered ESD protection structure, the control electrode is triggered by an RC circuit, wherein the capacitor is a diffusion capacitor implemented as one or more forward or reverse biased p-n junctions.

Abstract: An apparatus for providing electrostatic discharge protection includes a plurality of conductive circumferential extensions defined by overlapping circular voids between a first conductor surface and a second conductor surface.

Abstract: In an ESD protection structure and method utilizing substrate triggering for a high-voltage tolerant pad on a substrate, an ESD protection device has a source connected to the pad and a gate and a drain both connected to a ground, and a substrate-triggering control circuit is used to keep the substrate at a low voltage during a normal operation, and pumping the substrate to a high voltage during an ESD event for the ESD protection device to be triggered much easier. The substrate-triggering control circuit is implemented with an active device, thereby reducing the chip size for the circuit and the loading effect on the pad.

Abstract: A load is connected with a power supply. An energizing electric contact and a transient current contact are connected electrically in parallel with each other and can do time-coordinated making and breaking operation. A capacitor is connected in series with the transient current contact. During breaking operation of the energizing contact and keeping making state of the transient current contact, a transient current from the power supply flows into the capacitor and delay voltage increase of the energizing contact using voltage drop at an internal resistance of the power supply and the load.

Abstract: In an ion bean acceleration system, transient electrical arc suppression and ion beam accelerator biasing circuitry. Two-terminal circuitry, connectable in series, for suppressing arcs by automatically sensing arc conditions and switch from at least a first operating state providing a relatively low resistance electrical pathway for current between source and load terminals to at least a second, relatively high resistance electrical pathway. Selection of circuit component characteristics permits controlling the delay in returning from the second state to the first state after the arc has been suppressed.

Abstract: A noise-immune electronic circuit includes an input circuit for receiving an inbound signal through an input transmission line and comparing the inbound signal with a decision threshold to produce input data of the electronic circuit having one of predefined discrete levels depending on relative magnitudes of the inbound signal and the decision threshold and an output circuit for receiving output data of the electronic circuit and producing therefrom an outbound signal and forwarding the outbound signal onto an output transmission line. The input and output transmission lines are inductively coupled together so that a noise is introduced to the received inbound signal when a voltage transition occurs in the forwarded outbound signal.

Abstract: A solid state relay prevents the damage to photothyristor couplers when their performance characteristics vary slightly and enables phase angle control of an AC power supply using a less costly configuration than relays with photothyristor couplers having zero-crossing functions. The solid state relay includes a pair of input terminals configured to receive a control signal, a pair of output terminals configured to be connected to an AC power supply, a thyristor in parallel to the pair of output terminals configured to switch the AC power supply in response to the control signal. The solid state relay further includes two photothyristor couplers, each having a photothyristor, that are connected in series at a midpoint connection. The two photothyristor couplers are connected in parallel to the thyristor and are configured to control the thyristor. The solid state relay further includes two surge arresters connected in series at a midpoint connection that is connected to the photothyristor midpoint connection.

Abstract: A combination load controller for controlling application of power to a load such as a motor, has an input terminal coupleable to a power source, and an output terminal coupleable to a load. A conductive polymer and a protective, electromagnetic switch are disposed along a current path between the input and output terminals. The conductive polymer has a relatively low electrical resistance during conduction at nominal currents. The resistance of the conductive polymer increases substantially promptly upon conduction of excessive current, e.g., due to a short-circuit. In this manner the load is protected from even short bursts of excessively high, short-circuit current by the insertion of additional series resistance by the conductive polymer. The electromagnetic switch protects the line and load by opening the current path. The switch includes a current or voltage sensor coupled to a logic controller that opens the switch if over-current or under-voltage conditions persist for a predetermined period.

Abstract: A superconducting coil system includes an excitation power source, a superconducting coil, a DC circuit breaker connected in series between the excitation power source and the superconducting coil to disconnect them when quenching occurs, a protective resistor connected in a parallel manner to the superconducting coil for dissipating the energy accumulated in the superconducting coil when the quenching occurs, and a switch provided as a bypass of the DC circuit breaker, the switch being closed during the normal operation to pass the energy from the excitation power source to the superconducting coil through a resistor and being opened when the quenching occurs.

Abstract: A vacuum circuit breaker particularly suitable for use in an electric motor vehicle. The circuit breaker includes a vacuum interrupter to which a voltage is applied, the series combination of a capacitor and a switch which are connected in parallel with the vacuum interrupter, a provision for charging the capacitor with a voltage opposite the voltage applied to the vacuum interrupter, and a resistance connected in parallel with the vacuum interrupter. The vacuum interrupter, the resistance, and the series combination of the capacitor and switch form oscillation circuit having an oscillation frequency at least 2 KHz and an inductance of at least 1 .mu.H, with a commutating current of at least 5000 A for consuming energy stored in the circuit.

Abstract: A superconducting coil protective system comprises a quenching detector (QD) for detecting occurrence of a quenching in a superconducting coil (L) and generating a quenching signal indicative of the occurrence of the quenching. In response to the quenching signal, a voltage controller (VC) reduces an output voltage from a power source (PS) to zero or to a negative polarity. A current interrupter (CI) including a circuit breaker (CB) or a fuse (F) is connected in parallel to the superconducting coil (L) for allowing a first commutation of a current from the superconducting coil (L) to the current interrupter (CI) upon the reduction of the output voltage from the power source (PS). The system also comprises a protective resistor (RD) connected in parallel to the current interrupter (CI) for allowing a second commutation of the first-commutated current thereto upon the opening of the current interrupter (CI), whereby energy of the second-commutated current is dissipated in the protective resistor.

Abstract: Arrangement for arcless interruption of a-c load current in response to a current interruption command. Separable contact means serially connected with controlled impedance means, and parallel connected diversion means are intermediate the a-c source and the load. The controlled impedance comprises field effect transistors (FETs). Since FETs usually have only a single inherent junction, at least a pair of the FETs are oppositely poled so that load current can be cut off notwithstanding the direction of current flow when interruption is commanded. The pair of FETs may be connected back to back. An alternative embodiment has two branch circuits each comprising a FET and a separable contact means. Upon interruption load current is sequentially transferred from one to the other branch circuit and then to the diversion means.

Abstract: A device for protecting a direct current electrical power supply from disturbances caused by connecting to it or disconnecting from it an electronic system comprises at least one variable impedance component. The impedance of this component is controlled so that it has a very high first value when said electronic system is disconnected, a very low second value when said system is connected, a value varying slowly from said first value to said second value on changing from the disconnected state to the connected state and a value varying quickly from said second value to said first value on changing from the connected state to the disconnected state. The output current from said variable impedance component constitutes the supply current of said electronic system.

Abstract: A high tension circuit breaker comprising at least one circuit-breaking chamber and, in parallel with the circuit-breaking chamber, firstly a varistor in series with an interrupter, and secondly a tension-distributing capacitor. The circuit breaker has a linear resistor having a resistance lying in the range range 30 ohms to 300 ohms inserted in series with the varistor. The invention is particularly suitable for reactance circuit breakers.

Abstract: A fault current limiter according to the invention comprises a contact device (K) to the contacts of which is connected a resistor/inductor combination comprising a series connection of a first (R1) and a second (R2) resistor as well as a third resistor/inductor (R3) connected in parallel with the series-connected resistors. The second resistor consists of a resistor with superconducting properties, dimensioned such that the change from superconducting to normally-conducting state occurs when the critical current density of the resistor is attained.

Abstract: A circuit for limiting switch-on surge current to a load including a large capacitance includes a MOSFET whose controlled path is connected in series with the capacitance across power supply terminals. A resistor and a capacitor, having a relatively small capacitance, are also connected in series with the controlled path, and a junction between the resistor and capacitor is connected to a gate of the MOSFET via a further resistor to provide a negative feedback path for charging the load capacitance with a constant current when power is applied. A further capacitor prevents initial turn-on of the MOSFET, and a zener diode limits the gate voltage. An alternative arrangement using a differential amplifier is described. The resistive part of the load can be connected in parallel with the load capacitance, or to the power supply terminals for which it can be separately switched in dependence upon the gate voltage.

Abstract: An asymmetrical overvoltage protection circuit includes a series connection of varistors with a capacitance in parallel with only one of the varistors. The asymmetry may also involve a parallel connection of an inductance with the other of the varistors.

Abstract: A protection circuit for a semiconductor device is disclosed. This circuit is connected in series with a power semiconductor device to be protected, and is comprised of a circuit breaker and current-limiting device. The current-limiting device limits the overcurrent, thereby providing a time allowance until the circuit breaker begins operate.

Abstract: An electrical safety barrier which is adapted to pass a current returning from a hazardous area to a safe area but which will transmit negligible energy from the safe area to the hazardous area under fault conditions has in its return channel a fuse, shunt diodes and additional diodes. These additional diodes are either conventional rectifier diodes positioned at the safe-area end of the return channel or are Schottky diodes or diodes with a low forward voltage drop positioned at the hazardous-area end of the return channel.

Abstract: The contacts of an electrical switch, such as a magnetic contact reed switch or a magnetic contact reed relay used in a burglar alarm system, are protected from being fused together by transient current surges. This protection is accomplished by providing a normally nonconductive shunting path in parallel with the switch. The shunting path includes a voltage responsive device which is biased to conduction in response to a current surge to thereby complete the shunting path and allow the current surge to bypass the switch.

Abstract: An impedance arrangement is provided for use in a high-voltage circuit. For example, the impedance arrangement is useful in a circuit which includes reactance elements and a high-voltage circuit-switching device. The impedance arrangement limits transient inrush current and/or voltages in a first frequency range which occur in the circuit during closure of the circuit-switching device and damps transients in a second frequency range which occur in the circuit during opening of the circuit-switching device. The impedance arrangement is also useful in applications requiring tuning reactors and current-limiting to limit abnormal power-frequency currents, harmonics, transients, and/or high-frequency inrush currents. The impedance arrangement functions predominantly as an inductive impedance over a first frequency range; e.g., corresponding to the frequencies of transients encountered during the closing of a circuit-switching device.

Abstract: An electric protection apparatus is provided for protection against current faults of different intensities, including, in series in an internal circuit, a first switch with automatic opening, which is controlled by moderate current levels, and a second switch with automatic opening having short circuit current limiting properties; a zinc oxide voltage limiting component, which is placed in parallel across this latter, has a fairly low stabilization threshold so that diverted currents, flowing through it at the time of opening on a short circuit, extend as far as the resistive portion of the characteristic which follows the stabilization level portion.

Abstract: The circuit breaker displays a commutation device (4) and a semiconductor valve arrangement (6) which is connected in parallel with the commutation device (4), an isolating switching point (5) connected in series with the semiconductor valve arrangement (6) and a control circuit (11). The control circuit detects the polarity of the current to be disconnected and, together with a switching-off command (24), emits a response command to the commutation device (4) when the detected current flows in the direction of conduction of the semiconductor valve arrangement (6). When the current to be disconnected is interrupted in the semiconductor valve arrangement (6) after the commutation device (4) has responded, the control circuit (11) emits a release command to the isolating switching point (5) forming an isolating gap. As a result, the semiconductor valve arrangement (6) is isolated and the switching-off process is terminated.

Abstract: In a circuit having an electro-mechanical relay, the contacts of which are subject to arcing, bridging across the electro-mechanical relay in a manner configured to begin conducting electrical current around the electro-mechanical relay prior to closing the electro-mechanical relay and to continue conducting electrical power around the electro-mechanical relay for a predetermined time after the onset of separation of contacts of the electro-mechanical relay pursuant to discontinuance of current flow through the electro-mechanical relay. An optical coupler is provided to ascertain a current flow through the relay coil effected to close the electro-mechanical relay contacts, and activates a shunt device in bridging electrical current flow around the electro-mechanical relay. The shunt device is provided to be substantially non-load carrying while the electro-mechanical relay is closed. Utility is found in protecting electro-mechanical relay contacts against damage due to arcing.

Abstract: An input protection circuit is provided which prevents positive and negative voltages significantly higher than a supply voltage potential from damaging operational circuitry connected to an input terminal. A bipolar transistor has current conducting electrodes connected between the supply voltage and the input terminal. A first MOS transistor is coupled to the bipolar transistor for selectively eliminating a forward biased junction between the base and collector of the bipolar transistor in response to the sign and magnitude of an input signal. A second MOS transistor is coupled to the bipolar transistor for selectively eliminating a forward biased junction between the base and emitter of the bipolar transistor in responses to the sign and magnitude of the input signal.

Abstract: Load current is diverted from a circuit breaker, when it is opened, through a commutation circuit. The latter has a capacitor, inductance and solid state switch serially connected with the output of a bridge rectifier. The input of the bridge is connected across the breaker. The switch is turned on to discharge the precharged capacitor to form a current pulse, presenting an extremely low resistance across the bridge input and causing load current diversion.

Abstract: Power to a load is controlled by actuation of an inductive circuit from a first condition of low inductance to a second condition of higher inductance in response to a preselected overcurrent condition. In a first preferred embodiment, the inductive circuit comprises a pair of coils electrically connectible so that magnetic fields produced by current flow in the coils oppose each other in the first condition, reducing the magnetic flux and thus the effective inductance of the circuit. The magnetic fields are either neutral to each other or reinforce each other in the second condition, giving rise to a higher inductance. Alternatively, the inductive circuit may include one or more fixed value inductors interposed between a power supply and a load in response to an overcurrent condition.

Abstract: An inductive device composed of a bead (10) of magnetic material, such as ferrite, has an aperture through which an electrical conductor (13) is adapted to pass and a reset winding (14) wound thereon and connected to a source of constant current. The constant reset current resets the bead of magnetic material so that the maximum volt-second absorbtion capability of the bead is available for preventing destructively high current spikes from flowing through the electrical conductor. The inductive device is advantageously used in the d.c. supply of the power transistors (101 and 102) of an inverter (100) to protect the transistors from current surges due to the simultaneous conduction of the transistors.

Abstract: A spark suppression circuit for a battery charger includes a large filter capacitor connected in series with a semiconductor switch across the terminals of the battery charger. The battery charger does not have any output voltage even though the input is energized because the circuit includes a device to delay supplying of voltage until after the charger output terminals are connected to a battery to be charged. The semiconductor switch is non-conductive until the battery charger output terminals are actually connected to the battery to be charged. At this time, a bias circuit connected across the charger output terminals supplies a bias to turn on the semiconductor switch so that only at that time is the filter capacitor connected across the charger output terminals, and hence this suppresses the possibility of a spark upon connection of the charger output terminals to the battery to be charged.

Abstract: Arcless circuit interruption from metallic contacts is accomplished by the combination of a solid state current interrupter with a control circuit and an impedance circuit. The impedance circuit diverts the contact circuit current through the solid state current interrupter prior to initiating contact separation. The contacts then open without sufficient current transfer to establish an arc.