Abstract: The present invention discloses a device for evaluating and demagnetizing residual magnetism quantity of a power transformer. A main circuit comprises a switching power supply the two ends of which are respectively connected with a filter capacitor and a resistor in parallel. A forward end of the switching power supply is connected with a main switch in series. A rear end of the main switch is connected with a series branch of a sixth switch and a first resistor, a series branch of a first switch and a second switch, and a series branch of a third switch and a fourth switch are connected in parallel. A driving circuit is respectively connected with driving ends of the main switch, the sixth, first, second, third and fourth switches. A control circuit is connected with the driving circuit for sending an instruction to the driving circuit.

Abstract: A micro-power wireless access method and apparatus for the Internet of things for power transmission and transformation equipment involves a time synchronization process, a traffic channel access process, a control channel configuration information access process, and a control channel burst information access process. In the time synchronization process, an aggregation node determines a delay parameter and other parameters based on a timeslot in which traffic information randomly transmitted by a sensing terminal is located, and the sensing terminal adjusts transmission time of a corresponding frame based on the parameters. The traffic channel access process adopts a mode in which one-way reporting is mainly used, to minimize working time of a sensor. The present disclosure realizes limited two-way communication on a control channel, supports configuration of a sensor cycle, a threshold, and other parameters, and supports a retransmission mechanism on the control channel for important alarm information.

Abstract: Systems and methods for processing measurement data in an electric power system include acquiring the measurement data by a phasor measurement unit (PMU) coupled to a line of the electric power system, and inputting a plurality of the measurement data within a predetermined time window into a K-nearest neighbor (KNN) for identifying bad data among the plurality of the measurement data, wherein when one of the plurality of measurement data contains a bad datum, the machine learning module sends the bad datum to a denoising autoencoder module for correcting the bad datum, wherein the denoising autoencoder module outputs a corrected part corresponding to the bad datum, and when one of the plurality of measurement data contains no bad datum, the machine learning module bypasses the denoising autoencoder module and outputs the one of the plurality of measurement data as an untouched part.

Abstract: A lightning strike probability-based coordinated power control method for an energy storage system and a load adjusts output power of an energy storage system and a regulatable load based on a real-time predicted lightning strike probability. This reduces a correlation between a power grid in a lightning region and an external power grid, minimizes impact of a lightning strike if any on the external power grid, and decreases an economic loss due to the lightning strike in the lightning region. The present disclosure establishes a relationship between the output power of the energy storage system, the regulated power of the regulatable load, and a lightning strike probability in a same region, and then regulates the power of the energy storage system and the regulatable load in real time based on the lightning strike probability.

Abstract: Provided is a live measurement method for three-winding transformer loss based on windowed frequency shift. The method includes: step 1: providing an improved live calculation equation of a three-winding transformer loss; step 2: processing a collected x(t) signal by windowed frequency shift calculation; step 3: solving an amplitude and a phase of the collected x(t) signal via discrete Fourier transform of a frequency shift signal; and step 4: calculating a no-load loss and a load loss of a three-winding transformer.

Abstract: An SVM-based secure access method for wireless terminals. Step 1, establish a wireless network security model based on the communication scenarios of the wireless terminal and the wireless base station; establish the channel feature vectors based on the wireless network security model and the frames received by the wireless base station; Step 2, use the pre-trained SVM model to examine the channel feature vectors of the frames, determining whether the frames are legitimate signals; Step 3, determine whether the wireless terminal with at least one frame sent is a legitimate terminal based on whether at least one of the frames sent is a legitimate signal. The frames sent by the wireless terminals that access the wireless base station are examined to effectively determine legitimate terminals by improving the SVM parameter combination optimization method of differential evolution and the differential evolution method with an adaptive improvement of the control parameters.

Abstract: Disclosed is a low-voltage DC power distribution fast switching device. The device includes a positive output terminal electrically connected to a positive pole of a load, and no less than two switching circuits connected in parallel with each other; the switching circuit includes a positive input terminal electrically connected to a positive pole of common negative power supplies, a supplementary diode cluster composed of no less than one diode connected in series, and a thyristor connected between the positive input terminal and the positive output terminal; the positive input terminal is electrically connected to an anode of the supplementary diode cluster and an anode of the thyristor, and the positive output terminal is electrically connected to a cathode of the complementary diode cluster and a cathode of the thyristor.

Abstract: State estimation in an electric power system includes acquiring electrical measurements from the electric power system at a reporting rate of the electrical measurements, processing the electrical measurements into sequence data including positive sequence data, processing positive sequence data by an observable state estimator to generate a plurality of estimated states including a plurality of estimated observable states, parameters of the observable state estimator being updated by a first training module in a first time thread, processing the plurality of estimated states by an unobservable state estimator to generate a plurality of estimated unobservable states, parameters of the unobservable state estimator being updated by a second training module in a second time thread independent of the first time thread, and outputting a plurality of final estimated states generated by concatenating the plurality of estimated observable states and the plurality of estimated unobservable states.

Abstract: A lightning prewarning-based method for active protection against a lightning strike on an important transmission channel includes collecting meteorological element data, and establishing a transmission line-specific lightning strike probability prewarning model; using a maximum probability of a lightning strike prewarning level as a lightning strike prewarning level; performing equivalence calculation on a large-scale regional power system, using a minimum sum of a power loss risk cost and a regulation cost as an optimized objective function, and establishing a power flow transfer optimization model; and comparing a sum of a regulation cost and load power loss risk cost caused after the tie line is disconnected if regulation is performed before a lightning strike, and a load power loss risk cost caused if regulation is not performed, and when the regulation cost is not greater than the load power loss risk cost, performing regulation before the lightning strike.

Abstract: Disclosed are a method and apparatus for smoothing a link-line power of an electrothermal microgrid using a thermal storage heat pump cluster.

Abstract: Disclosed are a dynamic lightning protection method and system. The method includes detecting lightning in real time and tracking a position of a thunderstorm; and performing dynamic lightning protection and control on an electrical grid according to an electrical grid control strategy before the thunderstorm reaches or affects the electrical grid. Further disclosed is a dynamic lightning protection system.

Abstract: Disclosed is a fault current controller for a direct current power grid, which includes a primary circuit and a controller. The primary circuit includes an inductor, a filter capacitor, a resistor, an IGBT switch, a diode, a contactor and a Hall current sensor. The inductor, a first resistor and a second contactor are connected in series and are connected to a first contactor in parallel. A first branch including a second resistor and a first diode, a second branch including a third resistor and a second diode, and the inductor are connected in parallel; the filter capacitor, the IGBT switch and the first resistor are connected in parallel. The Hall current sensor is arranged in the series circuit. The controller controls the IGBT switch and the two contactors in the primary circuit to form different on-off combinations.

Abstract: Provided is an accurate load shedding system and method based on a power-dedicated wireless network. The system includes: a control master station layer, a control substation layer and a terminal user access layer. The control master station layer includes a control master station apparatus and an optical/E1 conversion device. The control substation layer includes an optical/E1 conversion device, a control substation apparatus and a wireless access device. The terminal user access layer includes a wireless core network, a base station and a control terminal. The wireless access device is connected to the wireless core network through Ethernet. The wireless core network is connected with the base station through an optical fiber. The control terminal is connected to a wireless network of the base station through customer premise equipment (CPE).

Abstract: Disclosed is a method for calculating radio interference suffered by a communication device mounted on an electric power tower. The method includes: establishing a relative position model of the communication device mounted on the electric power tower and transmission lines, calculating interference field strength of the communication device on the electric power tower, and determining whether the radio interference field strength at the mounting point satisfies the requirements.

Abstract: Provided is an emergency accurate control method and system for large-scale interruptible loads. The method includes: acquiring, by a region control master station, a sheddable load sequence table; acquiring, by the region control master station, a first to-be-shed load; performing, by the region control master station, minimum under-shedding matching layer by layer according to the first to-be-shed load, and shedding a sheddable load corresponding to control substation matching with the first to-be-shed load; and sending, by the region control master station, a second to-be-shed load to the corresponding control substation for load shedding if the second to-be-shed load exists.

Abstract: Disclosed is a method for calculating a transient overvoltage at a direct current (DC) sending end by taking into account a dynamic process of a control system. First, a first reactive power consumed by a converter station is calculated based on system operation parameters and a DC closed-loop transfer function. Then, a transient voltage change rate is calculated based on the first reactive power and a second reactive power on an alternating current (AC) side. Finally, the transient voltage change rate is iterated to obtain the transient overvoltage. According to the technical solution provided by the embodiments of the present disclosure, the transient overvoltage is determined based on the system operation parameters and the closed-loop transfer function of a DC line, the dynamic process of control parameter change caused by a control action of the control system after a fault occurs can be determined by the closed-loop transfer function of the DC line, whereby the transient overvoltage can be determined.

Abstract: Provided are an accurate load shedding system, and a communication method and an access apparatus thereof. The access apparatus includes: two E1 interfaces, eight optical fiber interfaces, a CPU and an FPGA. The two E1 interfaces are respectively connected to a control apparatus A and a control apparatus B of a control substation. The eight optical fiber interfaces are respectively connected to eight control terminals. The FPGA includes eight optical fiber transceivers respectively connected to the eight optical fiber interfaces through serial interfaces, and two E1 transceivers respectively connected to the two E1 interfaces through serial interfaces. Each optical fiber transceiver includes a reset submodule. Each E1 transceiver also includes a reset submodule. The CPU is connected to the FPGA through a parallel bus.

Abstract: Disclosed are a method and apparatus for smoothing a link-line power of an electrothermal microgrid using a thermal storage heat pump cluster.

Abstract: The embodiment of the invention provides a measurement method and a measurement device for quality of a power distribution and utilization channel. The method comprises the steps of determining priority of each branch in the power distribution and utilization channel of which the quality is to be measured; and determining quality of the power distribution and utilization channel of each branch according to the priority. The method and the device are used for improving monitoring strength on a whole optical fiber channel, and enhancing application universality.

Abstract: The present invention discloses a device for evaluating and demagnetizing residual magnetism quantity of a power transformer. A main circuit comprises a switching power supply the two ends of which are respectively connected with a filter capacitor and a resistor in parallel. A forward end of the switching power supply is connected with a main switch in series. A rear end of the main switch is connected with a series branch of a sixth switch and a first resistor, a series branch of a first switch and a second switch, and a series branch of a third switch and a fourth switch are connected in parallel. A driving circuit is respectively connected with driving ends of the main switch, the sixth, first, second, third and fourth switches. A control circuit is connected with the driving circuit for sending an instruction to the driving circuit.