Abstract: A method, an apparatus and a device for suppressing a first HVDC commutation failure under an AC system fault are provided. The method includes: obtaining a three-phase voltage of a converter bus, and calculating a zero-sequence component amplitude and an ?? component amplitude; calculating a first trigger-angle command for a single-phase fault and a second trigger-angle command for a three-phase fault; selecting a smaller one of the first trigger angle command and the second trigger angle command as a trigger-angle command for an extinction-angle controller; and adjusting a trigger angle of the HVDC transmission system by using the trigger-angle command as an upper limit value for an output of the extinction-angle controller of the HVDC transmission system.

Abstract: Disclosed are a tungsten hexafluoride preparation method and apparatus based on photoelectric synergy. A photocatalyst and metal tungsten are sequentially filled in a discharge area of a plasma reactor in a direction of gas entry, and the discharge area of the plasma reactor is irradiated with light at the same time; the background gas generates a large amount of plasma in the discharge area, SF6 undergoes decomposition under the synergistic effect of photocatalysis and plasma, SF6 is decomposed to generate fluorine atoms and low-fluorine sulfides such as SF5 and SF4. The generated fluorine ions, SF5, SF4 and low-fluorine sulfides further react with metal tungsten to generate WF6 specialty gas, which not only realizes the utilization of fluorine resources of SF6, but also replaces highly toxic fluorine gas with non-toxic SF6 exhaust gas in the plasma reactor for reaction, thereby ensuring safe operation and low energy consumption.

Abstract: Method for determining parameter of a passive impedance adapter applicable to VSC-HVDC, including: S1. obtaining VSC-HVDC impedance and VSC-HVDC impedance curve X(f) based on VSC-HVDC impedance; S2. estimating upper limit value of the main capacitor in the passive impedance adapter; S3. calculating adapter parameter curve Xadapter(f); S4. determining value of the main capacitor and varying value of the main resistor until min[X(f)?Xadapter(f)] is maximized; determining whether min[X(f)?Xadapter(f)]>k holds; S5. If min[X(f)?Xadapter(f)]>k does not hold, increasing the value of the main capacitor and performing steps S2-S4 until min[X(f)?Xadapter(f)]>k holds when the value of the main capacitor is within the range of the value of the main capacitor, storing the parameters in an available parameter set; S6. reducing the value of the main capacitor, and storing the parameters when min[X(f)?Xadapter(f)]>k holds in the available parameter set; S7.

Abstract: Disclosed are a tungsten hexafluoride preparation method and apparatus based on photoelectric synergy. A photocatalyst and metal tungsten are sequentially filled in a discharge area of a plasma reactor in a direction of gas entry, and the discharge area of the plasma reactor is irradiated with light at the same time; the background gas generates a large amount of plasma in the discharge area, SF6 undergoes decomposition under the synergistic effect of photocatalysis and plasma, SF6 is decomposed to generate fluorine atoms and low-fluorine sulfides such as SF5 and SF4. The generated fluorine ions, SF5, SF4 and low-fluorine sulfides further react with metal tungsten to generate WF6 specialty gas, which not only realizes the utilization of fluorine resources of SF6, but also replaces highly toxic fluorine gas with non-toxic SF6 exhaust gas in the plasma reactor for reaction, thereby ensuring safe operation and low energy consumption.

Abstract: A voltage source type direct-current ice melting apparatus, a flexible interconnection system and a control method are provided. The voltage source type direct-current ice melting apparatus includes a starting unit, a modular multi-level converter and a measurement control unit. The flexible interconnection system includes two voltage source type direct-current ice melting apparatuses having the same circuit structure. The measurement control unit acquires set values, that are input by a user, of relevant parameters and then processes the set values, that are input by the user, of the relevant parameters and measured values, measured in real time by the measurement control unit, of the relevant parameters, thereby determining and sending a control signal, so as to control an operating state of the modular multi-level converter in the apparatus or system.

Abstract: The present invention discloses a maleic anhydride modified voltage stabilizer, a preparation method, and use thereof, which belongs to the technical field of high voltage and insulation. The present invention discloses a maleic anhydride modified voltage stabilizer represented by Formula 1 and a preparation method thereof. (1) Maleic anhydride and 2,4-dihydroxybenzophenone are dissolved in tetrahydrofuran to obtain a mixture. (2) In a protective gas atmosphere, the mixture obtained in step (1) is added with a catalyst and stirred, centrifuged with added water, and an obtained precipitate is dried, thereby achieving the maleic anhydride modified voltage stabilizer. The present invention also provides the use of the maleic anhydride modified voltage stabilizer in a cross-linked polyethylene high voltage AC cable insulating material.

Abstract: A lattice-based proxy signature method, apparatus and device, a lattice-based proxy signature verification method, apparatus and device, and a storage medium. Polynomials are randomly selected in rings to calculate public and private keys of nodes, and the magnitudes of proxy public and private keys are the same as the magnitudes of public and private keys of an original signer. Therefore, compared with existing proxy signature schemes, the present application has smaller lengths of public and private keys and higher storage efficiency. Proxy signature information generated in the present application shows a signature of the original signer and also shows a signature of a proxy signer. Once a proxy signature is created, the proxy signature cannot be repudiated by the proxy signer, and has strong non-repudiation and strong unforgeability. The proxy signature method has the advantage of resisting quantum computer attack.

Abstract: A rapid detection device for multi-channel sporadic transient partial discharge, comprising a CPU and several partial discharge detection circuits. The partial discharge detection circuits are connected to a plurality of ports of the CPU one to one, respectively. First, a partial discharge pulse signal is filtered and amplified by means of a partial discharge pulse signal processing module in the partial discharge detection circuits, and is then inputted to a comparator, and a reference voltage passes through the CPU and is sent to a reference voltage processing module for amplification, filtering and other processing, and then is inputted to the comparator, so that the comparator processes same according to the partial discharge pulse signal and the reference voltage and then inputs same to a trigger. Finally, according to a level signal at an output terminal of the trigger, the CPU determines whether partial discharge occurs in a circuit to be detected.

Abstract: Disclosed are a passive triggered-power electronic tap-changer device and a contact device. The power electronic tap-changer device comprises: two taps, a main contact, two auxiliary contacts, two trigger contacts, an output terminal, two thyristors, and four voltage divider resistors, which can achieve the passive triggering of a power electronic switch by means of controlling the auxiliary contacts and the trigger contacts. Provided in the present invention is a contact device for the passive triggered-power electronic tap-changer, comprising: at least two stationary contacts, a main contact, two thyristor trigger contacts, two thyristor auxiliary contacts, and a drive shaft, wherein the main contact, the thyristor trigger contacts, and the thyristor auxiliary contacts are fixed to the drive shaft, the contact device can switch the power electronic switch to different stationary contacts by means of controlling the rotation of the drive shaft, and maintains the switching time sequence of passive triggering.

Abstract: The present application relates to a composite resin-based semi-conductive shielding material, prepared from raw materials including following components: 55 to 65 parts by mass of a composite resin, 20 to 30 parts by mass of electrically conductive fillers, and 0.9 to 2 parts by mass of a cross-linking agent, wherein the composite resin is a composite of a low-density polyethylene resin and an ethylene-acrylic acid resin, and the ethylene-acrylic acid resin is at least one of an ethylene-ethyl acrylate resin or an ethylene-butyl acrylate resin.

Abstract: An electric power stability control simulation model construction method and apparatus, and an electric power stability control simulation system. According to an external interface function extracted from a stability control device program, a corresponding callback interface function is generated by using the external interface function, and an electric power stability control simulation model is constructed by means of the callback interface function in combination with the correspondence between the callback interface function and the external interface function. When the electric power stability control simulation model is executed to perform a simulation test, the corresponding external interface function can be called by means of the callback interface function, so that the function simulation of the corresponding stability control device program can be realized.

Abstract: A device, a method for determining relative positions of power consumers based on a high-frequency signal, and a computer-readable storage medium are provided. The device is applied to a distribution transformer supply zone. The device includes a resonance or signal generator and a direction detector, the resonance or signal generator is disposed in a user electricity meter, the direction detector is disposed on a power line, the resonance or signal generator is configured to transmit a high-frequency signal or generate resonance in response to the high-frequency signal; the direction detector is configured to monitor a voltage and a current of the high-frequency signal flowing into the user electricity meter, and determine, based on a phase difference between the voltage and the current, a relative position relationship of two adjacent user electricity meters on the power line.

Abstract: A response interaction system for intelligently interacting with a low-voltage user includes: a distribution network and system master station, an intelligent electric meter, a mobile APP, an intelligent interaction terminal, an intelligent gateway, and a low-voltage user load. In the process of the low-voltage user participating in the demand response, the distribution network and system master station publishes a demand response plan and a demand response notification through the mobile APP, the low-voltage user receives the demand response plan and the demand response notification through the mobile APP, the low-voltage user is connected to the intelligent interaction terminal through the mobile APP and controls a load to operate or not operate through the intelligent gateway, to perform the demand response task.

Abstract: A method and a system for determining a direct current (DC) loop impedance are provided. The method includes: establishing an impedance model for a DC loop of a high-voltage direct current (HVDC) system; scanning parameters in the HVDC system based on the impedance model, to obtain a feasible region of each of the parameters; substituting, for each of the parameters, the parameter in the feasible region into a DC loop impedance equation, to obtain an impedance corresponding to the parameter, the DC loop impedance equation being obtained by transforming the impedance model; and comparing, for each of the parameters, the impedance corresponding to the parameter with a target impedance value, and determining the impedance that meets the target impedance value and the parameter corresponding to the impedance as an optimal impedance and an optimal parameter of the DC loop.

Abstract: The present disclosure provides a parameter design method for a series passive impedance adapter applicable to a VSC-HVDC transmission system, to resolve the technical problem that high-frequency resonance may occur when impedance of a VSC-HVDC transmission system is mismatched with that of a sending-end or receiving-end grid. A parameter design goal of the present disclosure is that reactive power consumed by a series passive impedance adapter is not more than A times rated power of a converter, and a loss of the series passive impedance adapter in a fundamental wave is B times the rated power of the converter. The parameter design method for a series passive impedance adapter applicable to a VSC-HVDC transmission system in the present disclosure can realize a positive impedance characteristic within a concerned frequency band and completely eliminate a risk of harmonic resonance.

Abstract: An integrated circuit-based nano-relay, comprising: an integrated circuit system of the nano-relay constructed according to an integrated circuit module built from a combinational logic circuit. An integrated power data processing algorithm is called by means of the integrated circuit module to perform signal processing on an input power signal, and power service data is output, that is, an integrated circuit is mainly constructed by means of the combinational logic circuit, the protection logic of the nano-relay is achieved by means of a hardware circuit module, and a response speed of the relay is improved.

Abstract: The present invention provides a polypropylene cable protective layer and a preparation method thereof. The polypropylene cable protective layer sequentially includes a dielectric layer, a buffer layer and an insulating layer from the inside to the outside, and the thickness of the dielectric layer accounts for 5%˜12% of the thickness of the polypropylene cable protective layer; the thickness of the buffer layer accounts for 17%˜25% of the thickness of the polypropylene cable protective layer; the dielectric layer, the buffer layer and the insulating layer are respectively obtained by the wrapping of a polypropylene film A, a polypropylene film B and a polypropylene film C. The polypropylene cable protective layer of the present invention forms a dielectric gradient, and realizes the improvement of the insulation strength and voltage level of the power cable, and the increase of the transmission capability.

Abstract: A trusted anonymous voting method includes: performing a hash operation on original voting content to obtain a hash output including a commitment value cvi; blinding the commitment value cvi based on information of other voters to obtain commitment value tuples {tilde over (c)} and {tilde over (x)}; signing the commitment value tuple {tilde over (c)} by using an ESDSA to obtain a signature tuple {tilde over (s)}; and establishing a vote tuple ({tilde over (c)}, {tilde over (s)}, {tilde over (d)}) based on the commitment value tuple {tilde over (c)}, the signature tuple {tilde over (s)} and a signature tuple {acute over (d)} of other voters, and uploading the vote tuple (?, ?, {acute over (d)}) and the commitment value tuple {tilde over (x)} to the blockchain, where signature tuple {tilde over (d)} is generated in a case that other voters verify the signature tuple {tilde over (s)} and the signature tuple {tilde over (s)} passes the verification, and the commitment value tuple {tilde over (x)} is used to decry

Abstract: A timestamp generation method and apparatus, and an electronic device and a storage medium, which are used for solving the technical problem of recorded information being easily leaked because a trusted third party is usually needed as a timestamp authority for recording in a traditional trusted timestamp generation method. In the present invention, the method comprises: acquiring a file record; calculating a hash value of the file record; sending the hash value to a random issuer, and receiving a signature result returned by the random issuer, wherein the signature result is generated after the random issuer signs the hash value and a receiving time, and the receiving time is the time when the random issuer receives the hash value; and storing the signature result in a blockchain as a timestamp of the file record.

Abstract: Disclosed are a voltage source converter based high voltage direct current (VSC-HVDC) high-frequency resonance suppression method, system, and device. The method includes: when an effective value of an actually input alternating current (AC) voltage is reduced from a normal value to meet a preset condition, making the virtual electrical quantity completely equal to the actual electrical quantity, and performing full real-time tracking for the actual electrical quantity to improve dynamic characteristics of a power system at the moment of a fault; and after performing the full tracking for a period of time, if the effective value of the actual AC voltage is less than a preset threshold, performing adaptive tracking until the actual electrical quantity recovers to a stable value. The present disclosure can reduce a risk of high-frequency resonance of a VSC-HVDC, avoid deteriorating dynamic characteristics of the VSC-HVDC, and improve safety of fault ride-through of the VSC-HVDC.