996 results about "Protective relay" patented technology

The invention relates to an operation and safety monitoring simulation system for a power system, which comprises a power system full digital real-time simulation subsystem used for simulating the operation of a large-scale power system in real time and providing simulation data to other subsystems, a power market simulation subsystem used for simulating and training power market transaction, a PMU / WAMS subsystem used for carrying out real-time dynamic monitoring and analysis on a simulated power system, an SCADA / EMS subsystem used for monitoring and analyzing the simulated power system, a fault information management subsystem used for managing and comprehensively utilizing fault information, a power system dynamic safety assessment and early warning subsystem used for carrying out safety assessment and early warning on the current power system and carrying out safety verification on the operation mode of a future plan, a safety and stability control system performance test subsystem used for testing the performance of a protective relay device, a power system stabilizer (PSS) and other automated equipment as well as a safety and stability control system and equipment, a power system fault diagnosis subsystem used for carrying out on-line diagnosis and intelligent safety alarming on the fault of the simulated power system and providing a dispatching control decision under the fault condition, and a power system recovery control subsystem used for recognizing the state of the fault of the simulated power system, searching and inferring the power supply path of an outage region and providing a power grid recovery control strategy. The system can simulate the operation of a large-scale power grid in real time, and can be used for searching and comprehensively testing the technology and software of various power systems in dispatching, operation, control and other aspects.

An adapter is provided for a communication device. The adapter includes an elongated hollow shell and a foldable adapting element. The foldable adapting element includes an input half part and an output half part pivotally rotatable with each other between an expansion accommodating position and a fold operation position. The output half part includes an output port for a transmission connector in the communication device. The input half part includes a set of power input ends corresponding to the power output port in the back cover mobile power source of the communication device. When located in the fold operation position, the output port can be plugged into the transmission connector, and the power input ends can be correspondingly connected to the power output port.

Apparatus for determining the frequency of an ac power signal, includes sensing circuitry to sense the ac signal. In a digital implementation of the invention, a double average of the samples is generated by a processor as the sum of the most recent sample, twice the next most recent sample plus the third most recent sample. The least mean square of a running window of the most recent double average signals is generated to avoid discontinuities at the zero crossings and to reduce the effects of noise. The frequency is determined from this least mean square value of the window of double average signals. As implemented in a protective relay, a trip signal is generated if the frequency is out of limits.

A method and system for programming and implementing automated fault isolation and restoration of high-speed fault detection of circuits in power distribution networks using sequential logic and peer-to-peer communication is provided. High-speed fault detection of circuits in power distribution networks uses protective relay devices (14) segmenting a distribution line (11) having Intelligent Electronic Devices (IED) (22) associated with switching devices (20) communicating peer-to-peer via a communication system (30) to provide fast and accurate fault location information in distribution systems with sequential logic.

The invention discloses an electric automobile high-voltage power-on circuit and a control method thereof. The circuit comprises a battery pack, a positive relay, a negative relay, a pre-charge resistor, a pre-charge relay and a pre-charge capacitor, wherein the positive relay, the negative relay, the pre-charge resistor and the pre-charge relay are connected between the battery pack and a load; the pre-charge capacitor is arranged at the two ends of the load; certain ends of the positive relay and the negative relay are connected to a master positive end and a master negative end of the battery pack respectively; the other ends of the positive relay and the negative relay are connected with the load; the pre-charge resistor and the pre-charge relay form a series branch; the series branch is arranged at the two ends of the positive relay and forms a parallel circuit; the pre-charge resistor is connected to the master positive end of the battery pack. The detection of an actual state of the relay is realized, a fault can be timely reported under the condition that a high-voltage loop fails, high-voltage power-on operation is stopped, and the safety of the battery system and the vehicle is guaranteed.

A method for providing interactive self-supporting screen with scalable flexibility. Such a support combined with a flexible computer screen enables reliable touch, writing, mobile drawing, accurate selection, and virtual typing without requiring desk or table space. A flexible screen when rolled up will provide a reduced footprint device for storage or transport and the selective deployment to the required size as the operator desires. Consisting of Protective layer (Flexible-paper feel surface, can be touch enabled), Organic Light Emitting Display (OLED) layer, back light layer (if required), Backing (flexible, slat seam filling; blotter feel), Slats or slabs (Curtin or blinds like), and pullout, telescoping, or swing out cantilever supports.

The present invention relates to protective frames for portable electronic devices that can also be used to support the device in an upright display position. In particular, embodiments of the present invention include protective frames for electronic devices that have a support arm attached to, integrated with, and recessed into the frame by a hinge or other secure mechanism that is movably attached, allowing it to be supported in horizontal and vertical positions. Embodiments of the present invention may be used with any type of portable electronic device including portable media players and portable cellular telephones. It may be particularly useful with portable electronic devices that use a touchscreen input.

Disclosed is an apparatus and method for detecting a loss of a current transformer connection coupling a protective relay to a power system element of a three-phase power system and providing a plurality of secondary current waveforms of the three-phase power system to the protective relay. The apparatus includes a first logic circuit and a second logic configured to provide corresponding first and second binary signals in response to respective comparisons of calculated current value(s) of a plurality of like-phase digitized current sample streams to respective threshold values. The apparatus also includes a set reset flip-flop having a set input adapted to receive the first and second binary signals to provide a third binary signal. The third binary signal indicates loss of a current transformer connection when the set input is asserted and indicates no loss of a current transformer connection when the reset input is asserted.

A differential protection system for power transformers using Rogowski coils as current sensors can support an inrush current detection method based on sensing lows in the derivative of the sensed current. Effective detection of power transformer inrush conditions can enable blocking of a protection relay during inrush where the differential current may exceed a differential threshold value indicative of a fault without the presence of an actual fault. The outputs of the Rogowski coils, being proportional to the first time derivative of the sensed current, may be useful in the inrush detection method. Also, with reduced saturation concerns, the Rogowski coil protection system may employ a single slope response with increased sensitivity. A discrete time sampling technique for identifying low di / dt portions within the sensed current also may be useful in detecting power transformer inrush conditions.

A protective relay having an embedded web server to allow communication with a remote device having a standard web browser package. The relay can receive and transmit HTML files according to the HTTP protocol over a communications network. The relay can receive commands from the remote device, and can generate and return requested data to the remote device.

The invention concerns a method of impedance groundfault detection for differential protection of an overhead transmission line in a three-phase high voltage electric power transmission system which comprises many lines (1,12) and many protection relays (2,4), which comprises the following steps: 1) in prefault condition: —measuring the differential current (I); —measuring the phase voltage (II) at the relay location; —measuring the phase current (III) the relay location; —calculating the differential admittance (IV), with the following equation: (formula (V)). With (VI): the positive sequence impedance of the line-protected. 2) In operating condition: —measuring the differential current (VII); —measuring the phase voltage (VIII) at the relay location; —measuring the phase current (IX) at the relay location; calculating the differential admittance (X), with the following equation: (formula (XI)); —detecting a high impedance groundfault detection, if the following formula is verified: (XII) with (XIII); B0=the total line admittance.I_dphpre(I)U_fphpre(II)I_fphpre(III)Y_dpre(IV)Y_dpre=I_dphpreU_fphpre-0.5ZL1I_fphpre(V)ZL1(VI)I_dph(VII)U_jph(VIII)I_jph(IX)Y_d(X)Y_d-I_dphU_jph-0.5ZL1I_jph(XI)abs(Y_dN)>0.75Bd(XII)Y_dR=Y_d-Y_dpre(XIII)

In preferred embodiments, an expandable and modular protective mobile device case apparatus comprises a protective shell configured to receive a mobile device; a circuit board located within the protective shell said circuit board comprising a USB hub and a mode selection switch, wherein the USB hub is in electrical communication with the mode selection switch; and a male plug member in electrical communication with the mode selection switch and configured to transfer electrical signals from the mode selection switch to the mobile device.

Provided is an operation method of an electric peeling device for the protective cores of waste cable. Clamping mechanisms are arranged at the two ends on an operation table. A heater, a cutting mechanism and a stripping mechanism are sequentially arranged along the running direction of cables between the two clamping mechanisms. An insulating layer collection hole is arranged between the cutting mechanism and the stripping mechanism. The operation method comprises the following steps: adjusting the height of the telescopic rods on the clamping mechanisms; adjusting the distance between the blade of a cutter on the cutting mechanism and the inner core of a cable and the distance between the blade of a separator on the stripping mechanism and the inner core of the cable; adjusting the centers of the mechanisms to the same axis line; and heating, cutting and stripping the insulating layer of a to-be-processed cable in sequence. The device has a simple structure. The operation method is simple. The use effect is good. Operation by workers is facilitated. The labor intensity of workers is reduced greatly. The stripping effect is good, and the production efficiency is high. The method is suitable for stripping the rubber sheaths of all kinds of cables. High cable core recovery efficiency is achieved.

The invention discloses a safety chain system of a wind generating set and a fault rapid identification method thereof. According to different safety chain trigger objects, a non-intelligent safety relay and a conventional relay are adopted to construct a safety chain loop by a hard-wired series mode so as to form a unit safety system; the state of the safety system is effectively monitored; for the same protected object, the safety chain loop adopts a redundancy design mode; and at least two independent safety chain protection connection points can simultaneously operate, so that the state of effectiveness loss of the safety chain, which is caused by output adhesion of a certain equipment object protection relay connection point, can be more effectively prevented. The safety chain system of the wind generating set and the fault rapid identification method thereof, which are disclosed by the invention, are simple to implement, effective to monitor and low in cost; and meanwhile, the safety and reliability of the safety chain system of the wind generating set are protected by adopting a multilevel protection mode.

The invention discloses a method for allowing a protective film or protective glass to be in communication with a mobile phone. The method comprises the steps that a user downloads and installs a mobile phone APP according to mobile phone model network recognition; one or more APP hidden icons are planted into the edge of a display window or a region without operation icons of a mobile phone touch screen by the mobile phone APP; the protective film or the protective glass is attached to the mobile phone touch screen; touch keys are manufactured on the non-touch-response part at the upper end or the lower end of the mobile phone touch screen or the protective film or the protective glass; a certain touch key is operated, so that the changes of capacitive sensing at the APP hidden icons of the touch screen are caused; due to CPU data input and output, the mobile phone APP can be quickly and conveniently waken up or exit. According to the method, besides increasing the traditional use such as scraping resistance and fouling prevention of the mobile phone for the user, through smart phone system development, the user can conveniently download APP settings as needed by himself / herself and operate the region, which originally does not have a touch response, outside the display window of the mobile phone to quickly achieve wake-up or exit of the commonly used and required APP. In this way, the application region of the mobile phone is enlarged, and experience and playability are improved.

An arc suppression circuit in a protection relay having trip contacts is used to turn off a battery-powered solenoid and trip an AC power circuit breaker. The arc suppression circuit uses a switch-control circuit to control the turning off of a semi-conductor switch so that the semi-conductor switch provides a current path around the trip contacts, and is carrying all, or substantially all, of the load current, before the trip contacts are opened. When the trip contacts begin to open, the switch-control circuit holds the semi-conductor switch on for a sufficient time to prevent an arc from becoming established before turning the semi-conductor switch off. In a second embodiment, the arc suppression circuit provides a second switch-control circuit. This second switch-control circuit is configured to accept control signals from a microprocessor within a protection relay. The microprocessor turns the semi-conductor switch on before the contacts begin to open, thereby providing a current path around the contacts before the contacts begin to open. The microprocessor turns the semi-conductor switch off after a time sufficient to prevent an arc from becoming established.

Embodiments of the present disclosure relate to an integrated transformer health monitoring architecture and associated processes. In one embodiment, a method can provide: receiving protection data of a transformer from the at least one protection relay device; receiving health monitoring data of the transformer from the at least one monitoring and diagnostics (M&D) device; analyzing the received protection data and the received health monitoring data using a common time reference; monitoring, diagnosing, analyzing, or predicting a failure of the transformer based at least in part on analysis of the received protection data and the received health monitoring data; and generating an instruction to modify operation of the transformer in response to monitoring, diagnosing, analyzing, or predicting a failure of the transformer.

Disclosed herein is an apparatus for connection to the secondary terminals of a CT to prevent CT damage and electric shock when the secondary terminals are opened, by providing an input signal and operating a relay circuit to short the CT secondary terminals. The apparatus monitors opening of the CT secondary terminals, and to prevent accidental opening, determines opening and provides an over voltage breaking upon opening. To prevent false operation of the protecting relay connected to the secondary terminals caused by the over voltage generated by accident other than opening of the CT secondary terminals, a secondary delay time of operation of the protecting relay is provided that can be variously set by DIP switch or otherwise, allowing the user to choose a desired setting. Further, expected over voltage values can be set according to load characteristics, allowing the apparatus to operate during voltage above the set value.

A method and an adaptive distance protection relay for compensating for a remote line end infeed effect during determination of a distance to a resistive fault on a three-phase power transmission line. It is assumed that a fault current flows through the fault resistance. A fault loop impedance is first calculated by a known algorithm from phase voltages and phase currents. A shift of the fault loop impedance is determined from the fault loop impedance, the impedance of the transmission line for the positive current sequence and the phase angle of a complex fault current distribution factor, where the fault current distribution factor is the ratio of the fault loop current to the fault current. The distance to fault is calculated by subtracting the impedance shift from the fault loop impedance and dividing the result by the impedance of the transmission line for the positive current sequence.

A system for collecting data and monitoring the operation of electrical circuits, such as branch circuits at a substation is provided. The system collects data from a plurality of sensors coupled to a plurality of electrical equipment associated with a circuit. The data from the sensors is collected and used to determine the activation of the electrical equipment, such as a protective relay for example. The data is further transformed to allow assessment of the circuit's performance against desired parameters.

The invention relates to a protective frame for a mobile communication device having a power charging port. The protective frame has a retractable frame body, including a main frame body; a sliding element for reciprocatingly sliding along a direction with respect to the main frame body between a retracted protection position where the mobile communication device is fixedly framed by the retractable frame body and a stretched auxiliary power supply position; and a fastening element for fixing the sliding element with respect to the main frame body at the retracted protection position and the stretched auxiliary power supply position. The protective frame also includes an auxiliary battery adapted for being detachably installed in the retractable frame body and electrically connected to the power charging port of the mobile communication device, when the sliding element are fixed with respect to the main frame body at the stretched auxiliary power supply position.

A method and apparatus for high-speed fault detection of circuits in power distribution networks utilizing protective relay devices (14) segmenting a distribution line (11) having Intelligent Electronic Devices (IED) (22) associated with switching devices (20) communicating peer-to-peer via a communication system (30) to provide fast and accurate fault location information in distribution systems.

A protection relay for an electrical switching apparatus for a load includes a number of voltage sensors structured to sense voltage applied to the load, a number of current sensors structured to sense current flowing to the load, and a processor cooperating with the number of voltage sensors and the number of current sensors. The processor determines a fault current available at the load. An output cooperates with the processor. The output is structured to output the determined fault current and a number of: incident energy at the electrical switching apparatus, and a personal protective equipment level operatively associated with the electrical switching apparatus. The processor determines from the determined fault current the number of: the incident energy at the electrical switching apparatus, and the personal protective equipment level operatively associated with the electrical switching apparatus.

The invention discloses a current adaptive protecting method which belongs to the technical field of an electric power system. The current adaptive protecting method comprises the following steps: utilizing a fault network equivalence simplifying method and a fault steady state component theory to obtain a relation between a node voltage and a fault steady state injection current before failure happens; utilizing a network system parameter matrix to construct the linear mapping relation between the fault steady state injection current and a fault steady state branch current; and utilizing a fault steady state current of a related branch to form novel current adaptive protection. According to the invention, the network system parameter matrix is used for eliminating the effect of a distributed power supply on the fault steady state current of each branch, thereby avoiding a protective relaying false operation caused by the accessing of the distributed power supply. A setting algorithm is simpler and more practical. A main protection scope is 72.88%-72.94% of the full length of a circuit. A protection scope of spare protection which extends to a subordinate circuit is less than the protection scope of main protection; therefore the demand of protection matching is met.

The invention relates to an intelligent monitoring system for a flexible passive protective net. The intelligent monitoring system of the flexible passive protective net includes a dangerous source capture system, a signal processing system and an alarm system. Under a condition that the signal processing system determines that dangers happen in the protective net and / or the protective net reaches a dangerous degree, alarm signals and / or intelligence information are / is sent in one or more methods. Fiber bragg grating sensors are preinstalled on lower support ropes of the flexible passive protective net. Through monitoring the tension of the lower support ropes of the protective net, signals related with rock fall and breakage of the protective net are monitored in a real-time manner and then the signals are returned to a fiber bragg grating demodulator.

A multichip module comprises a flexible circuit having conductive patterns on its surface(s) to which microelectronic device(s) are attached. The flexible circuit is enclosed and supported by two rigid frames, which may further be provided with protective heat spreading covers. Contact pads on the rigid frame(s) may be configured to engage a mating socket or they may be solderable to a printed circuit board.