628results about How to "Prevent misoperation" patented technology

A three-busbar two-section switch standby self-casting apparatus, belonging to power distribution field, includes two power supply lead-in circuit breakers, three busbar segments and two section breakers. Two standby self-casting devices being mounted on the position of the two section breakers; the standby self-casting device being equipped with a current detection loop, a voltage detection loop and a control circuit; the current detection loop using the signal of a two-path lead-in current transformer as ''non stream'' criterion, and using the current signal of the corresponding section breaker as ''over current'' criterion; while the voltage detection loop using the voltage signals of the two busbar segments, neighboring the corresponding section breaker, as ''pressure / non-pressure'' criterion. The standby power supply self-casting device includes a electrification discrimination circuit, a first and a second startup condition judgment circuit, a standby self-casting motion circuit and a rear acceleration motion circuit. The invention also discloses standby self-casting method for the apparatus. The apparatus implements power supply rapid automatic switching when the lead-in is failure under different running modes of the three-section busbar, and ensures the power supply reliability under accidents status.

The invention discloses a thunder-lightening induced solid-phase arc-extinguishing lightning arrester. The thunder-lightening induced solid-phase arc-extinguishing lightning arrester mainly consists of a lightning arrester shell, an arc-extinguishing rotary table, an electric conduction metal plate, a starting rod, a clamping rod, an induction coil, an arc-extinguishing barrel and a counting pointer; the arc-extinguishing rotary table is arranged inside the lightning arrester shell, and a flat spiral spring for pushing the arc-extinguishing rotary table to rotate is arranged at the central position of the arc-extinguishing rotary table; the electric conduction metal plate is arranged at the upper part of the arc-extinguishing rotary table; the arc-extinguishing rotary table is provided with a plurality of arc-extinguishing gas pills in the peripheral direction; one side of each arc-extinguishing gas pill is provided with a trigger electrode and a groove respectively, one end of each trigger electrode is connected with one of trigger ends of the corresponding arc-extinguishing gas pill through a lead, and the other ends of the trigger electrodes extend out of the edge of the arc-extinguishing rotary table; and the other of the trigger ends of the corresponding arc-extinguishing gas pill is connected with the electric conduction metal plate through a lead. The thunder-lightening induced solid-phase arc-extinguishing lightning arrester is simple in structure, reasonable in design, high in arc-extinguishing ability and stable and reliable to work, and the arc-extinguishing gas pills are changed quickly and conveniently.

R, G and B LEDs are used as a light source of an electronic flash. Electric energy is supplied to a capacitor to the LEDs. A system controller controls light emitting amounts of the LEDs so that a color temperature of the electronic flash light becomes a color temperature that has been manually set with a color temperature setting switch or a color temperature of a light source determined by color temperature sensors.

The invention relates to the technology of relay protection, in particular to an adaptive judging method for distinguishing transformer excitation surge current from failure current; the defects of easily causing false action of transformer differential protection and delayed protection exist in the prior art; in the invention, sampling calculation of current on each side, ratio differential calculation, harmonic braking calculation, switching condition judgment, external failure judgment, timely or gate harmonic braking judgment and harmonic increment judgment are carried out in turn, and then final judgment result of each phase is obtained according to the ratio differential, harmonic braking signal, harmonic increment signal and timely or gate harmonic braking signal of each phase so that whether to have tripping operation is determined. The method avoids the generation of false action, saves unnecessary overhauling, and also guarantees the security of system.

The invention relates to a method for positioning a short-circuit fault of a distribution network based on distributed intelligent multi-calibration. The method comprises the following steps of: arranging a plurality of intelligent agents in the distribution network and establishing a modeled multilevel multi-verification short-circuit fault positioning rule for different operating modes of the distribution network; in the operation process of the distribution network, monitoring operation information of a local current distribution network in real time through each distributed intelligent agent; once the current is out of limit, sending a current out-of-limit signal to the directly-adjacent intelligent agent and a superior intelligent agent and checking whether a short-circuit fault early-warning signal exists locally; if so, assuring that the short-circuit fault happens locally; otherwise, waiting for receiving the current out-of-limit signal sent by the directly-adjacent intelligent agent; and after delaying the signal for time t, according to the local current out-of-limit signal and the received current out-of-limit signal, carrying out rule matching and multi-condition calibration to determine a fault diagnosis result by utilizing a local short-circuit fault positioning rule library and combining a wiring type of the distribution network and the position of the intelligent agent.

The invention relates to an adaptive cascade direction interlocking relaying method based on GOOSE (Generic Object Oriented Substation Event), which comprises the following steps: 1) initial interlocking directions of protective relays are set according to an initial interlocking direction tuning rule; 2) a directional element judges the direction of a current fault current which is compared with the initial interlocking directions by a direction comparator to judge whether the directions of two parts are the same, if yes, the step 3) is carried out, if not, IN2 is gated, and a interlocking signal is output to OUT2; 3) the direction comparator gates IN1, and outputs the interlocking signal to the OUT1 and the direction of the output signal is opposite from the initial interlocking direction at this time; 4) a receiving virtual terminal judges whether the interlocking signal is received, if yes, the interlocking is carried, if not, the step 5) is carried out; and 5) an over-current element judges whether the current fault current exceeds a local over-current protection starting fixed value, if yes, a trip signal is sent. In comparison with the prior art, the method has the advantages that the safe and reliable operation of a system is ensured and applicability is good.

The invention discloses a new bus protection method for realizing rapid CT wire break based on current variation and a complete of technical scheme. In the invention, the variations of the original current sampling values of connecting units of a bus are compared with a preset threshold to form the number of upward changed current units, the number of downward changed units and the number of units without change. By means of comparison between the number of three changed units and the variation direction of braking current, normal CT wire break and faults of the bus are distinguished, thus the CT wire break can be effectively judged and misoperation for bus protection can be prevented.

The invention provides an exciting current emulation calculating method at the time of direct-current magnetic biasing. The calculating method comprises the steps of: constructing an electric network model according to a target electric network; building a transformer magnetizing current curve according to the transformer no-load excitation characteristic curve; setting direct-current magnetic biasing exciting current I0, and revising the transformer magnetizing current curve; after setting other node and shunt parameters of the electric network, carrying out emulation operation; and obtaining steady-state exciting current according to the emulation data, calculating the direct-current component I'0, revising the transformer magnetizing current curve again until I'0=I0, when I'0=I0, comparing I2 and KxbI1, and carrying out inrush current locking operation when |I2| is larger than kxb * |I1|. According to the invention, emulation calculation can be rapidly carried out on the transformer exciting current at the time of set direct-current magnetic biasing, the harmonic wave characteristics of the transformer exciting current can be effectively identified, and the influence of the exciting current at the time of direct-current magnetic biasing on the transformer protection is analyzed, thus the phenomenon that the protection element fails to operate or has unwanted operation is prevented and favorable influence is brought for the power transmission and transformation system.

The invention provides a hidden failure diagnostic method of a digital transformer protector measuring loop, which belongs to the technical field of secondary power device failure diagnosis. The hidden failure diagnostic method comprises the following steps: 1. a hidden failure diagnostic computer collects the current measuring value amplitude at the high voltage side and the low voltage side of a differential protector of the digital transformer and the current and voltage measuring values of a back-up protector (1) and a back-up protector (2) in real time; 2. the collected current and voltage measuring values are respectively analyzed and compared by a method of analysis of variance according to the relativity of the input information of the differential protector as well as the back-up protector (1) and the back-up protector (2); and 3. the hidden failure diagnostic result is analyzed and outputted. The method can monitor whether the current and voltage measuring values of the digital transformer protector as well as the back-up protector (1) and the back-up protector (2) are normal or not in real time and judge whether the measuring loops of the digital transformer protector as well as the back-up protector (1) and the back-up protector (2) have failure or not hereby.

This invention refers to a TA saturation identifying method and current differential protection method for same, which adopts the sectional wave shape integral method to judge whether the TA occurring, it needs a cycle and is simple and effective, said method does not influence protection action speed in area serious fault and effectively prevent error action in out area fault. Said invention is a self-adaptive method with very less influence to performance of protected unit.

The invention relates to an anti-interference electricity protecting method and an anti-interference electricity protecting apparatus for a motor or electric equipment under an interference electricity state of a grid. The method comprises a step of judging and identifying an interference electricity fault of the grid, which is the step for a process of judging the timeout of the over-current locking under-voltage, as well as a step of charging the protecting device; and the method can transmit an interference electricity recovering restarting signal depending on a set value of the delayed starting time. The anti-interference electricity protecting apparatus comprises a hardware module which is used for implementing an anti-interference electricity protecting function and an interference electricity state judging logic function module which is used for identifying an interference electricity fault of the grid. According to the technical scheme of the grid interference electricity identifying, the over-current locking under-voltage judgment, the under-voltage timeout locking judgment and the voltage recovery judgment are adopted, to effectively distinguish the grid fault from a motor short circuit accident, a grid interference electricity fault and a grid power-loss accident as well as other faults or accident events differing in property and type, thereby avoiding error action events of the protecting device in case of the motor short circuit accident and the grid power-loss accident, and guaranteeing the equipment and the personnel security.

A method for locating a touch position is provided. The method is adaptable to an optical touch panel, wherein the optical touch panel has a plurality of visible light sensors and a plurality of corresponding invisible light sensors that are arranged as an array. In the present method, sensing signals of the visible light sensors and the invisible light sensors are read. The sensing signal of each visible light sensor is converted into a first binary code according to a first setting parameter, and the sensing signal of each invisible light sensor is converted into a second binary code according to a second setting parameter and a third setting parameter. An AND operation is performed on all the first binary codes and all the second binary codes to obtain a plurality of logic operation values, so as to locate a position touched by a user on the optical touch panel.

The invention discloses a method for judging lock by zero sequence voltage and current, relating to a line protection method. In the existing line protection, in particular in weakly electrically and strongly magnetically connected double circuits, a mutual inductance electric potential is easy to cause longitudinal zero sequence direction protection misoperation. The technical scheme of the method disclosed by the invention comprises the following steps of: (1) sampling voltage and current wave forms of a mutual inductor by a line protecting device, and figuring out the sizes of zero sequence voltage and zero sequence current of a fundamental wave; and (2) when the line protecting device judges that a power grid is abnormal and zero sequence power flows from a line to a bus, allowing an element in a zero sequence direction to operate if the zero sequence voltage is larger than a zero sequence voltage threshold value and the zero sequence current is larger than a zero sequence current threshold value; otherwise, locking the elements in the zero sequence direction. Zero sequence current locking and zero sequence voltage locking conditions are added to protection in a longitudinal zero sequence direction, thus non-fault line longitudinal zero sequence direction protection misoperation caused by zero sequence mutual inductance can be prevented, and the reliability of longitudinal zero sequence direction protection in the weakly electrically and strongly magnetically connected double circuits is improved.

The invention relates to a checking method and device for correctness of virtual terminator association configuration of an intelligent substation. The method comprises the steps that primary equipment and the topological relation of the intelligent substation are obtained according to an SSD file of the intelligent substation; the secondary function configuration, corresponding to the primary equipment, of secondary equipment is obtained according to the SSD file; the logic connection relation between secondary functions of the secondary equipment of the intelligent substation is obtained according to the primary equipment, the topological relation and the secondary function configuration corresponding to the primary equipment; correctness of virtual terminator two-end IED / LD / LN association configuration in the logic connection relation is checked according to a preset rule. Secondary virtual circuit logic connection errors caused by virtual association configuration errors can be rapidly and effectively checked, maloperation caused by the virtual terminator association configuration errors is avoided, risk of misoperation of running equipment is reduced in the reorganization, expansion and debugging process of the intelligent substation, and safe production and reliable operation of the intelligent substation are ensured.

The invention relates to a fault locking method for relay protection in a digital substation. In the relay protection, a plurality of IED (Intelligent Electronic Device) distributed fault detection elements are integrated with various fault identification criterions to effectively identify faults of a power system; a protection device and intelligent unit double-fault locking mechanism is adopted, wherein a process layer communication CPU (Central Processing Unit) on the protection device only releases GOOSE (Generic Object Oriented Substation Event) trip locking and forwards a GOOSE trip signal to an intelligent unit on the premise that a trip command for protecting the CPU and a fault detection FD open command exist simultaneously; and the intelligent unit only releases locking and trips on the premise that the GOOSE trip command and the FD open command are received simultaneously. On the basis of network information sharing, the fault locking method provided by the invention is integrated with various fault identification criterions to effectively identify the fault of the power system by adopting the plurality of the IED detection elements, and prevents false tripping caused by IED abnormality so as to improve the reliability of the power system.

The invention discloses a standardized Hausdorff graphic similarity matching identification-based zero-sequence differential protection algorithm for a transformer. Waveform similarity matching identification is carried out on a self-produced zero-sequence current sequence and a neutral line TA current sequence for zero-sequence differential protection for the transformer by a standardized Hausdorff distance algorithm. The zero-sequence differential protection algorithm disclosed by the invention can effectively prevent maloperation of traditional zero-sequence differential protection caused by recovery surge after an external earth fault is eliminated under the condition of ensuring the same protection scope and transition resistance resisting ability as those of the traditional zero-sequence differential protection, and has obvious advantages in the aspect of quickness.

The invention discloses a method for preventing differential protection misoperation of a digital transformer caused by such errors as short circuit, open circuit and etc. on the secondary circuit of a current transformer. Criterions for the errors in the TA secondary circuit are as follows: when a digital transformer protection device is running normally (a primary system accessed by the transformer does not go out of order), if the TA secondary circuit error is determined as that one- or two-phase current drops by 30 percent or higher, and difference current exists, then, the TA secondary circuit is determined as being out of order. On the premise of sudden current change: the current after the sudden change drops rather than increases, and the primary system has errors, or at least one-phase current will increase; therefore, one- or two-phase current of three-phase current drops by 30 percent or higher at the side; meanwhile, the three-phase current at other sides does not vary. If the conditions are met, the TA secondary circuit is determined as being out of order; after the TA secondary circuit goes out of order, an alarm signal is launched, and a latched or an unlatched difference protection outlet can be selected.

The invention relates to an automatic switching transport network self-healing recovery method based on break before make, which is characterized in that an original service is firstly broken, a new service path is then established, and the transmitting and receiving of the line protection service are guaranteed to be in same route at any time; the self-healing recovery method concretely comprises two processes of service self-healing when the failure of a line fiber differential protection channel occurs, and service recovery when the failure of an original communication network is corrected; (1) when the failure of the line fiber differential protection channel occurs, the service self-healing process is as follows: a dynamic recovery channel based on control plane is arranged in the line fiber differential protection channel, the channel based on break before make is formed, the blocking state is opened, the channel time delay is recalculated, the operational parameters of a device are adjusted, and the self-healing process is finished; and (2) when the failure of an original communication network is corrected, the service recovery process is as follows: the ASON (automatic switch optical network) fault is corrected, the service reroute is broken to recover the channel, a line protection device monitors a channel fault, the ASON reestablishes the original designed route channel, and the service recovery is realized. The automatic switching transport network self-healing recovery method based on break before make realizes that the transmitting and receiving of the fiber differential protection channel are carried out in the same route at any time, the time delay during transmitting and receiving is maintained the same, and the automatic switching transport network self-healing recovery method based on break before make is applicable to the power line fiber differential protection service.

The invention discloses an adaptive-slope transformer zero-sequence differential protection method comprising the following steps: the zero-sequence current at the output end of a Y winding side of a transformer and the grounding zero-sequence current at a neutral point side of the transformer are compared to calculate the zero-sequence differential current and the brake current of the transformer; the size and direction of obtained zero-sequence power are calculated based on the zero-sequence voltage and the zero-sequence current at the output end of the Y winding side of the transformer, and the zero-sequence differential braking slope of the transformer is dynamically adjusted; when an external fault occurs, dynamically adjusted high slope is adopted in zero-sequence differential protection to prevent external metallic grounding and prevent transformer zero-sequence differential protection malfunction caused by CT saturation of the grounding zero-sequence current at the neutral point side; and when an internal fault occurs, low slope is adopted in zero-sequence differential protection. The invention further provides a corresponding device. The method and the device are used to monitor to-ground insulation of a power transformer in real time. An external grounding fault and an internal grounding fault of a transformer can be distinguished quickly and accurately. High sensitivity to internal faults is realized. Reliable braking can be achieved with use of high slope for an external fault.

A fault direction judgment method based on positive-sequence polarization voltage phase comparison includes the steps that the measuring voltage Um, the measuring current Im and the bus positive-sequence voltage Um1 at the installation position of a directional element are respectively acquired after a smart distribution network breaks down; a working voltage Uop is set; the direction of the fault is judged. The fault direction judgment method has the advantages that due to limitation of the minimum value, it can be guaranteed that correct actions can be carried out when a short circuit occurs at the tail end of the protection range due to the resistance smaller than the largest transition resistance, and the reverse-direction fault can be judged with high reliability. The fault direction judgment method has the advantages that a voltage dead area does not exist, the capacity for resisting transition resistance is high, the working characteristics are stable, and influences cannot be caused by large changes of the operating mode of a power distribution network system or obvious difference between distributed power supplies or complex load types or other working conditions.

The invention relates to a quick starting and vector calculation method for intelligent substation integrated protection, which belongs to the technical field of electric system protection and control. The method comprises the following steps: carrying out quick starting and vector calculation for a protection object 1; judging whether the protection object 1 carries out secondary starting or not, if so, carrying out protection processing according to the result of the vector calculation, judging whether faults occur, and taking corresponding measurements, otherwise, carrying out the quick starting and the vector calculation for a protection object 2; and in such a way, carrying out the quick starting and the vector calculation for a protection object m, and judging whether the protection object m carries out secondary starting or not, if so, carrying out protection processing, otherwise, terminating the quick starting and vector calculation. According to the quick starting and vector calculation method, the CPU resource can be flexibly utilized, so as to achieve an effect that an integrated protection platform has better stability, reliability, openness, scalability and maintainability.

The invention discloses a bus protection method for quick locking in CT (current transformer) asymmetric wire breakage. The bus protection method comprises the following steps of: calculating the electrical quantities of a differential current, a brake current, the sudden-change current of each branch, a zero-sequence current and the like; judging that the CT wire breakage occurs according to a criterion that the differential current increases while the brake current is unchanged, and starting differential protection if the CT wire breakage does not occur; selecting a suspected CT wire breakage branch according to whether a current exits in the branch of each circuit, and starting differential protection if the suspected CT wire breakage branch is not selected; and confirming the CT wire breakage according to information of the sudden-change currents and the zero-sequence currents of other branches except for the suspected CT wire breakage branch, and starting differential protection if the CT wire breakage cannot be determined. The protection method disclosed by the invention is capable of preventing the mistaken action of bus differential protection in case of CT asymmetric wire breakage and no high short-circuit current, and ensuring the correct action of bus differential protection regardless of whether the CT asymmetric wire breakage occurs in case of a high short-circuit current.

The invention provides a prediction method for current transformer saturation. The prediction method comprises the following steps: detecting a first current output from a high-voltage side current transformer of a transformer, and detecting a second current output from a low-voltage side current transformer of the transformer; calculating a first fundamental wave vector, a first DC (direct-current) component and a first total effective value of the first current, and calculating a second fundamental wave vector, a second DC component and a second total effective value of the second current; generating a current transformer saturation prediction signal according to the first fundamental wave vector, the first DC component, the first total effective value, the second fundamental wave vector, the second DC component and the second total effective value. By the method, the current transformer saturation can be predicted or detected effectively before the differential protection of the transformer caused by the current transformer saturation, so that the maloperation of the differential protection of the transformer can be effectively avoided.

The invention relates to an anti-TA saturation differential protection method and a device for a transformer. The differential protection method comprises the steps of collecting the current of a to-be-protected element; collecting N current sampling points with a current cycle; determining a starting time of a fault; on the condition that the variation of a braking current and the variation of a differential current occur simultaneously, judging the occurrence of an internal fault and starting the differential protection; on the condition that the variation of the braking current occurs before the variation of the differential current, judging the occurrence of an external fault and locking the differential protection; during the occurrence of the external fault, judging the conversion of the fault type from the external fault to the internal fault and starting the differential protection. According to the invention, whether an internal fault or an external fault occurs can be judged more accurately based on a preset criterion. Therefore, the differential protection malfunction of the current can be effectively prevented.

An electrical receptacle to prevent injuries deduced by misoperation is provided in the present invention. The electrical receptacle includes a power socket, a direct current (DC) power supply, a detecting switch, a controller, and a relay form a circuit loop for detecting whether a power plug is inserted into the power socket. The detecting switch is placed under the power socket without any electrical connection with the power socket. A live wire is connected to the power socket via a switch of the relay and a neutral wire is connected to the power socket directly. The switch of the relay closes on condition of the relay is electrified by the DC power supply.

The invention relates to a relay protection information safety protection method of electrical power system, which is based on mode match in the network. The inventive method uses the digital mutual inductor to collect the data of current and voltage to be transmitted to the transformer substation via the network; when the relay protection data judges that the electric network has accidence according to received data, to output motion signal, the relay protector via the network of transformer substation to collect the data of current and voltage of all circuits and bus in said substation to be output to be probability neural net, via which it processes the mode match and judges if the current and voltage data match known accidence mode to avoid the error motion of relay protection. The invention uses probability neural net to process mode match between the accidence data and the known accidence data to recognize the false accidence, to improve the information safety protection ability of relay protector, and the error motion of relay protector caused by receiving mistake data signal.

The invention relates to fault protection methods of converters, specifically to a modular multilevel converter bridge arm short circuit fault protection method. The method comprises the following steps of 1) setting a fault detection time gap [delta]t of modular multilevel converter bridge arm parallel protection switches; 2) setting a fault motion threshold value Q; 3) setting voltage threshold values Ulim.ac and Ulim.arm; 4) detecting voltage to ground Uac(t) of the alternating-current end of a modular multilevel converter and computing Q1=abs(aveage(Uac([delta]t)))-Ulim.ac; 5) detecting bridge arm voltage Uarm(t) of the modular multilevel converter and computing Q2= abs(aveage(Uarm([delta]t)))-Ulim.arm; 6) determining that a bridge arm short circuit fault occurs if Q2 x Q 1 > Q; and 7) trigging the bridge arm parallel protection switch of a sound phase when it is determined that the modular multilevel converter has the bridge arm short circuit fault. According to the invention, by employing the bridge arm parallel protection switches, the bridge arm short circuit fault time duration of the modular multilevel converter is shortened; the direct-current bias voltage borne by a transformer and the overvoltage borne by converter bridge arms are reduced; the equipment requirement and cost are lowered; and the economical efficiency and security are improved.

The invention provides a method and system for delay judgment of the fault direction of a bus circuit, a computer device and a computer readable storage medium. The method comprises the steps that thephase voltage and phase current of each phase in the alternating-current bus circuit of a high-voltage direct-current transmission inverter side are obtained, and the sequence voltage, sequence current and three-phase power of the bus circuit are calculated; whether a fault exists in the bus circuit or not is judged according to the phase voltage and the sequence voltage, and a corresponding fault signal is generated if the fault exists; after the fault signal is generated, the fault component of the sequence voltage, the fault component of the sequence current and the direction of the three-phase power are obtained through delay; according to the fault signal, the fault component of the sequence voltage, the fault component of the sequence current and the direction of the three-phase power, whether the fault happens to the forward direction of the bus circuit or the reverse direction of the bus circuit is judged, the influence of transient power reversing is avoided, and then the situation that a protection system is mistakenly operated is avoided.

The invention discloses a high voltage switch cabinet misoperation preventing device, comprising an operation hole for switch-on-off coaxial operation of a disconnecting switch and an earthing switch, a movable shading plate for controlling opening and closing of the operation hole, an interlocking mechanism of a vacuum circuit breaker and the disconnecting switch as well as the earthing switch, a cabinet door and disconnecting switch interlocking mechanism and an earthing switch and cabinet door interlocking mechanism. The misoperation preventing device can reliably prevent misoperation of switch-on-off operations of the vacuum circuit breaker, the disconnecting switch and the earthing switch and door opening and closing operations of a high voltage switch cabinet, and can ensure safety and reliability of operations; and the high voltage switch cabinet misoperation preventing device has the advantages of being simple in structure, occupying small space, increasing no volume of the high voltage switch cabinet, being simple and convenient to operate, and so on.