6291results about "Arrangements responsive to excess current" patented technology

In embodiments of the present invention improved capabilities are described for autonomous shifting of at least a portion of a lighting load off an energy distribution grid, comprising electrically connecting a lighting device to the energy distribution grid; causing the lighting device to interpret information obtained from an information source proximate the lighting device; and causing the lighting device to select from at least two different power sources based on the interpretation, where selecting may include a sharing of the load between the two different power sources, and where one power source may be the energy distribution grid.

A power supply control device for controlling power supply to a pair of terminals to which a load is connected, comprising a voltage measuring part for measuring a voltage which has a predetermined relationship with the voltage of the pair of terminals, a short circuit detecting part for detecting whether a short circuit exists between the pair of terminals based on the measured voltage and for making power supply to the pair of terminals stop when existence of a short circuit is detected, and a constant current supplying part for supplying a constant current though the pair of terminals; wherein the short circuit detecting part is configured to detect that the previously detected short circuit is eliminated when the voltage measured by the voltage measuring part is equal to or greater than a predetermined threshold value upon supplying the constant current through the pair of terminals.

A programmable power (PPSE) switching element including a front power transistor, a main switching transistor, and at least one reverse current blocking transistor in series, a gate of each of which is connected to a gate driver; an inductor and a shunt resistor connected in series with the transistors; a charge storage capacitor connected between ground and a junction located between the inductor and the shunt resistor; a high-speed NPN transistor, a collector of which is connected to the front power transistor and an emitter of which is connected to an output of the main switching transistor via the shunt resistor; a current measurement element in parallel to the shunt resistor; a voltage amplifier; and a high-speed MCU.

A fault detection mechanism for a LED string comprising a plurality of serially connected LEDs, the fault detection mechanism comprising: a control circuitry; and a voltage measuring means, in communication with the control circuitry, arranged to measure the voltage drop across at least one LED of the LED string, the control circuitry being operable to: measure the voltage drop, via the voltage measuring means, at a plurality of times, compare at least two of the measured voltage drops, and in the event the comparison of the at least two voltage drops is indicative of one of a short circuit LED and an open circuit LED, output a fault indicator.

A direct current arc fault circuit interrupter includes separable contacts and a trip circuit to trip open the contacts. The trip circuit includes a number of alternating current sensors structured to sense a current flowing through the separable contacts, a number of filter circuits cooperating with the AC current sensors to output a number of AC signals, a number of peak detectors cooperating with the filter circuits to output a number of peak current signals, and a processor cooperating with at least the peak detectors. The processor inputs the number of peak current signals as a plurality of peak current signals or inputs the number of peak current signals and determines the plurality of peak current signals. The processor also determines if the peak current signals exceed corresponding predetermined thresholds for a predetermined time, and responsively causes the contacts to trip open.

A method and apparatus for aggregating power from multiple sources generates a single direct current regulated voltage. The apparatus comprises a plurality of slave voltage converters and a master pulse width modulator circuit. Providing a plurality of direct current power sources, current is drawn through a plurality of lines connected to the plurality of direct current power sources. An open circuit voltage for each direct current power source is unknown. Each line of the plurality of lines has a line resistance. The line resistance of at least some of the plurality of lines may be unknown. The line resistance of at least some of the plurality of lines is large. The single direct current regulated voltage is generated from the drawn current.

A method and apparatus for managing DC arc faults. At least a portion of the method is performed by a controller comprising at least one processor. In one embodiment, the method comprises analyzing a signature of a signal of a power converter and determining, based on analysis of the signature, whether an arc fault exists.

The present invention provides a power regulation system and method with high speed signal settling capabilities for providing rapid active transient response to a microelectronic device. An active transient response system includes a power supply configured to receive external and / or internal signals indicating the occurrence of transient load conditions and to respond to the transient load conditions based on one or more of these signals. The system may further include a transient suppressor configured for early detection of transients, assisting in transient suppression, and early signaling of transient activity to the power supply.The system provides rapid recovery to steady state operation from the active transient response mode by using a digital compensator to quickly modifying the duty cycle and provide a voltage offset proportional to the transient microprocessor load step. Recovery is further improved by current rephasing techniques.

A protection circuit for a boost power converter provides input under-voltage protection and output over-voltage and over-current protection. The protection circuit includes a control power MOSFET connected in series between the ground of the boost power converter and the ground of the load. The arrangement of the circuit makes it easy to drive the gate of an N-channel power MOSFET and is ideal for current-limiting control, which utilizes the Rds-on of the MOSFET as a current sensing element. Neither a specific gate-driver nor a current sensing resistor is required, and thus high efficiency can be achieved. Furthermore, the slow slew-rate at the gate of the MOSFET provides a soft-start to the load. The protection circuit includes a temperature compensation circuitry to offset the variation of the Rds-on. A time delay circuit prevents the switching elements and protection elements from overload damage.

An electrical load is supplied with power from a driving power source, and a microprocessor (CPU) controls the opening / closing current supply rate (duty factor) of an opening / closing element in accordance with target current and driving power source voltage so that open loop control is carried out to achieve predetermined target current. The voltage between both the ends of a current detecting resistor connected to the ground side of the opening / closing element is input as a monitoring voltage from a current detecting amplifying circuit portion through a multichannel AD converter to CPU. When the error between the comparison target voltage corresponding to the target current and the monitoring voltage is above a first permissible error, CPU judges that there is an abnormality sign, and if the error is above a larger second permissible error, CPU judges that there is appearing abnormality. Accordingly, an abnormality sign of a semi-wire-breaking / semi-short-circuit state of the electrical load can be sensed, and abnormality notification can be carried out.

A method and apparatus for managing DC arc faults. At least a portion of the method is performed by a controller comprising at least one processor. In one embodiment, the method comprises analyzing a signature of a signal of a power converter and determining, based on analysis of the signature, whether an arc fault exists.

A voltage limiter device of an assembly of photovoltaic modules, including: (a) means (Z1) forming an electronic switch for a current of said assembly; (b) comparison means (Comp, R1, R2, C2) for comparing a voltage at the output of the limiter with a reference voltage value (Vref); and (c) means for controlling the means forming an electronic switch, depending on the result of the comparison carried out by the comparison means.

An arc fault detector system detects arcing faults in an electrical distribution system by monitoring one or more conductors and producing an input signal representing one or more electrical signal conditions in the circuit to be monitored. This input signal is processed to develop signals representing the electrical current flow through the monitored circuit and broadband noise signal components. The system analyzes these signals to determine whether an arcing fault is present, and if so, outputs a trip signal which may be used directly or indirectly to trip a circuit breaker or other circuit interruption device.

A system for providing real-time modeling of protective device in an electrical system under management is disclosed. The system includes a data acquisition component, a virtual system modeling engine, and an analytics engine. The data acquisition component is communicatively connected to a sensor configured to provide real-time measurements of data output from protective devices within the system under management. The virtual system modeling engine is configured to update a virtual mode of the system based on the status of the protective devices and to generate predicted data for the system using the updated virtual model. The analytics engine is communicatively connected to the data acquisition system and the virtual system modeling engine and is configured to monitor and analyze a difference between the real-time data output and the predicted data output. The analytics engine is also configured to determine the bracing capabilities for the protective devices.

System and method for protecting a power converter. A system includes a threshold generator configured to generate a threshold signal, and a first comparator configured to receive the threshold signal and a first signal and to generate a comparison signal. The first signal is associated with an input current for a power converter. Additionally, the system includes a pulse-width-modulation generator configured to receive the comparison signal and generate a modulation signal in response to the comparison signal, and a switch configured to receive the modulation signal and adjust the input current for the power converter. The threshold signal is associated with a threshold magnitude as a function of time. The threshold magnitude increases with time at a first slope during a first period, and the threshold magnitude increases with time at a second slope during a second period. The first slope and the second slope are different.

A new and improved type of ground fault interruption receptacle is mainly consists of an upper housing, a middle supporter and a lower holder. Two sets of female power-output socket 5, 6, a simulation test button (i.e. test button for fault detecting) and a reset button are disposed on the upper housing. A metal mounting plate is disposed between the upper housing and the middle supporter. At the two sides of the middle supporter is disposed a pair of metal conductors. Between the middle supporter and the lower holder is disposed a printed circuit board, and thereon a differential transformer within which an iron core is inserted, a reset guide member and a flat spring type of resilient off locking switch are arranged. Using the differential transformer and the resilient off locking switch, the receptacle of the present invention may detect whether the fault current exists and whether the damage of a certain element or member for power transmission occurs. If so, the receptacle of the present invention can electrically disconnect the power-out connectors with the relevant power-input connectors so as to accomplish the ground fault interruption.

A microprocessor based overcurrent trip unit which generates trip signals as an adjustable function of current and time, has a visual representation of the trip function on a front panel with 2-color LEDs associated with the trip function serving as indicators of trip conditions when red, and of a selected programmable parameter when green. The green LEDs flash to indicate parameter selected for modification in a program mode and illuminate steady in a view mode.

System and method for protecting a power converter. The system includes a duty-cycle detection component configured to receive a modulation signal, determine a first duty cycle corresponding to a first period of the modulation signal, compare the first duty cycle with a threshold duty cycle, and generate a duty-cycle comparison signal. Additionally, the system includes a threshold generator configured to receive the duty-cycle comparison signal and generate a threshold signal corresponding to a second period of the modulation signal, the second period being after the first period, and a comparator configured to receive the threshold signal and a first signal and to generate a first comparison signal. The first signal is associated with an input current for a power converter. Moreover, the system includes a pulse-width-modulation component configured to receive the first comparison signal and generate the modulation signal for adjusting the input current for the power converter.

The present invention is directed to a protective device configured to be disposed in an electrical distribution system between a source of electrical power and an electrical load. The electrical distribution system includes at least one line hot conductor, a line neutral conductor, and a line ground conductor. The line neutral conductor is connected to the line ground conductor at a termination point in the electrical distribution system. The electrical load includes at least one load hot conductor, a load neutral conductor, and a load ground conductor, the device comprises a conditioning circuit configured to monitor a differential current flowing through the plurality of line termination elements and configured to generate a conditioning signal in response thereto. The conditioning signal propagates in a path formed by the line neutral conductor and the line ground conductor to thereby reduce a differential current propagating in the at least one line hot conductor and the line neutral conductor. The conditioning circuit also is configured to neutralize a substantial portion of a current associated with a non-fault related electrical perturbation.

A system and method links batteries in parallel to conductors using wire bonds that act as fuses in the event of an overcurrent condition in a battery. To protect the wire bonds in the case of a larger overcurrent condition, a fuse may be added in series to the parallel batteries.

Disclosed is an adjustable over current protection circuit which advances the timing of enabling an over current protection mechanism according to an input voltage, therefore the delay problem resulting from the non-instant response of the over current protection circuit is compensated with a low power loss. The over current protection circuit includes a voltage divider, a voltage-to-current converting circuit, an adjusting circuit and a comparing circuit. The voltage divider divides an input voltage to generate an adjusted input voltage, and the adjusted input voltage is converted into an adjusted input current by the voltage-to-current converting circuit. The adjusting circuit then adjusts a current sensing voltage according to the adjusted input current to generate an adjusted current sensing voltage. Finally, the comparing circuit compares the adjusted current sensing voltage with a predetermined over current protection reference voltage to selectively enable the over current protection mechanism according to a comparison result.

A semiconductor switching element driving circuit comprises an overcurrent limiting circuit which instantaneously drops a voltage of a gate terminal of an IGBT when a main IGBT current becomes larger than a predetermined level i1. An overcurrent protection circuit which first decreases the main IGBT current at a first inclination when the main IGBT current becomes larger than the other level i2 lower than the i1 and then reduces the main IGBT current at a steep second inclination when it becomes smaller than another level i3.

A charging monitor has: a switch that is disposed between a load section having a storage battery and an external AC power supply supplying a current to the load section via a plurality of lines and interrupts the supply of the current from the external AC power supply to the load section; a current detection circuit that outputs a detection signal corresponding to a difference in level between currents flowing through the lines; a suppression circuit that suppresses a DC component contained in the detection signal; a filter circuit that filters a plurality of frequency components contained in the detection signal so that attenuation increases as a frequency becomes high; a rectifier smoothing circuit that rectifies and smoothens an output signal obtained when the detection signal passes through the filter circuit and the suppression circuit; and an electric leakage determination circuit that detects an electric leakage and shuts off the switch when the level of the signal smoothened by the rectifier smoothing circuit exceeds a preset reference level.

A non-invasive powerline communications system includes: means for generating communication signals at a first location for transmission on a powerline; means for reactively coupling the communication signals to the powerline; and means for receiving said communication signals at a second location.

A system for producing a simulated ground fault when arcing is present in an electrical circuit includes a sensor which monitors the electrical circuit. An arcing fault detection circuit determines whether an arcing fault is present in response to the sensor and produces a trip signal in response to a determination that an arcing fault is present in the electrical circuit. A ground fault simulator circuit produces a simulated ground fault in response to the trip signal.

A solid-state relay / breaker that can replace mechanical units to control any type of AC or DC load. Power MOSFETs or other transistors control a load current. A bypass current sensing path monitors MOSFET current and causes a shutdown through signal processing in the event of an over-current condition. This shutdown resembles that of a slow-blow fuse where the rate of shutdown is proportional to the value of the current. This prevents shutdown on momentary spikes or in-rush. In addition, temperature and internal power supply voltages are monitored to determine additional operational conditions where over-temperature or voltages out of range can also cause shutdown. The MOSFET and current sensing path are turned on and off in staggered timing with different slew rates to provide built-in hysteresis. The device can be manufactured in any type of package to match any type of environment or existing replacement requirement.

A circuit interrupter includes band pass filters cooperating with a current sensor to output bands having different, non-overlapping ranges of frequencies, peak detectors cooperating with the filters to detect corresponding peak current values, envelope detectors cooperating with the filters to detect corresponding occurrences from the bands being within corresponding predetermined magnitude ranges, a counter counting the occurrences, and a processor providing and disabling series arc detection when sensed current is greater than a first predetermined value. The processor determines tallies responsive to peak current values exceeding corresponding thresholds, determines series arcing from sensed current being less than the first predetermined value for a predetermined time, the tally for a current half-cycle being nonzero, and a count for the current half-cycle being different than the count for an immediately previous half-cycle of like polarity by at least a second predetermined value. A series chaos accumulator is increased responsive to series arcing.

An arc fault circuit interrupter system for use with an electrical circuit includes an arcing fault detector which monitors the electrical circuit and a controller which generates a trip signal in response to the detection of arcing faults. The controller may also generate one or more communication signals corresponding to information relating to the operation of the arcing fault circuit interrupter. The system may also include one or more of the following: a communication port which communicates to a user the information relating to operation of the arc fault circuit interrupter in response to the communication signals; a memory for retaining predetermined information related to the condition and operation of the arcing fault circuit interrupter, with or without a backup memory; and a combined self-test / reset switch.