13results about "Reactive/real component measurements" patented technology

The invention relates to the technical field of power system court management, and particularly discloses a court identification and user binding method based on a special transformer acquisition terminal, which comprises the following steps: separating harmonic interference generated by start and stop of an electric welding machine through a kurtosis index and time-frequency energy entropy fusion detection method, and extracting a fundamental voltage and a pure power signal; constructing a dynamic time bending model containing phase consistency and gradient feature constraint based on the fundamental wave voltage, and calculating voltage track similarity to judge electrical coupling; for the users with electrical coupling, dynamic weight power cross-correlation analysis is fused to generate a comprehensive decision value, and a space-time diagram neural network is utilized to update a transformer area topology structure online in combination with a historical topology change event, so that the dynamic determination of the transformer area to which the users belong is realized; through multi-dimensional feature fusion and anti-interference algorithm design, the problems of phase deviation and waveform distortion caused by electric welding machine harmonic waves are reduced, and the transformer area identification accuracy and real-time performance are improved.

The invention provides a mechanical characteristic monitoring method and system for a switch cabinet, and belongs to the field of power equipment detection, and the method comprises the steps: respectively obtaining the contact stroke of each phase of contact, the isolation knife current of each phase, the grounding knife current of each phase, and the motor current of each phase of a three-phase discrete switch of the switch cabinet in the switching-on and switching-off process; obtaining opening and closing time data of the circuit breaker in the opening and closing process; obtaining stroke characteristics of each phase of contact according to the contact stroke of each phase of contact; obtaining current characteristics of each phase according to the isolating knife current of each phase, the grounding knife current of each phase and the motor current of each phase; obtaining opening and closing characteristics according to the opening and closing time data; and monitoring the mechanical characteristics of the switch cabinet according to the contact stroke characteristics of each phase, the current characteristics of each phase and the opening and closing characteristics. The comprehensiveness and the accuracy of monitoring the mechanical characteristics of the switch cabinet and the effectiveness of fault identification can be improved.

The application discloses a non-invasive electrical appliance identification method based on a harmonic similarity algorithm. The method comprises the following steps: 1, first, learning process is carried out on the electrical appliance to be identified, in the learning process, the fundamental active power, the fundamental reactive power, the active power of each harmonic and the reactive power of each harmonic of each sample electrical appliance under the rated condition are measured; 2, the operation number N of the electrical appliance identification algorithm is initialized, N=0, and the N=N+1 operation is started; 3, the voltage and current time domain data of the unknown electrical appliance on the bus are collected; 4, the collected voltage and current time domain data are converted into frequency domain data through fast Fourier transform (FFT); 5, according to the current and voltage harmonics of different frequencies in the frequency domain data, the total fundamental active power, the active power of each harmonic and the reactive power of each harmonic under the current power consumption state are calculated. The non-invasive electrical appliance identification method based on the harmonic similarity provided by the application has a wider application occasion compared with the prior art.

A voltage management device according to the present disclosure includes a communication unit that obtains, for each of sections in a power system, a measurement value of a voltage measured by a smart meter connected to that section, where the sections are generated by segmentation between monitoring points, and a voltage estimation unit that estimates, for each of the sections, a voltage drop quantity and a voltage rise quantity in that section using the measurement value.

The invention provides a frequency power output characteristic test method and device, electronic equipment and a storage medium, and the test equipment is connected with tested equipment through an isolation transformer, and obtains a real-time active component and a real-time reactive component of a current signal outputted by the tested equipment in a two-phase rotating coordinate system; the test equipment changes the output power and frequency of the tested equipment based on the real-time active component, the real-time reactive component and a preset control strategy; and obtaining a frequency-power output characteristic curve of the tested equipment through a fitting algorithm.

The present disclosure is directed toward systems and methods for measuring electric current in a multi-wire cable, as well as the apparent and real power associated with an electrical load connected to the cable. A probe comprising an array of small form-factor, high-speed magnetometers is operatively coupled with the cable such that the magnetometers partially surround the cable. Each magnetometer detects the composite magnetic field at its location, and this plurality of measurements is used to generate a magnetic-field map. The contributions of the current flow in each wire are identified by deconvolving the magnetic-field map, enabling their locations to be determined and monitoring of the current and power flow. A sensor included in the probe is used to determine the phase of the applied voltage. The phase difference between the voltage and current is then used to determine the real power dissipation of the load.

The invention provides a method and device for testing output characteristics of a converter, electronic equipment and a storage medium. The voltage-power output characteristics of the converter are tested through the following steps: acquiring a three-phase voltage value at a common connection point and a three-phase current value injected by test equipment; tracking a PCC voltage phase in real time, and establishing a synchronous two-phase rotating coordinate system; converting the sampled three-phase current value from a three-phase static coordinate system to a two-phase rotating coordinate system to obtain a corresponding collected active component and a collected reactive component; the test equipment controls the output current based on the difference value between the given active component and the collected active component and the difference value between the given reactive component and the collected reactive component, so that the converter generates corresponding voltage response; and obtaining a voltage-power output characteristic curve of the converter based on the change of the three-phase voltage value at the common connection point under different disturbance conditions. The problem of a black box current device in an existing train auxiliary power supply system is solved.

The invention provides a station fault voltage ride-through index automatic identification method based on step response analysis, and the method comprises the steps: collecting measurement data before and after fault voltage ride-through, carrying out the preprocessing of the measurement data, obtaining a line voltage effective value, and drawing a line voltage effective value curve, an active power curve, and a reactive current curve; searching split1-4 on the line voltage effective value curve, searching point1, point3, point5 and point6 on the voltage effective value curve according to the split1-4, and calculating to obtain a line voltage effective value qualification index based on coordinate values of the point1, the point3, the point5 and the point6; according to the split1-4, point7-16 is searched on the active power curve, and an active power eligibility index is obtained through calculation based on the coordinate value of the point7-16; according to the split1-4, point17-22 is searched on the reactive current curve, and on the basis of the coordinate value of the point17-22, a reactive current eligibility index is obtained through calculation; a line voltage effective value eligibility index, an active power eligibility index and a reactive current eligibility index are stored, and eligibility analysis can be rapidly and accurately carried out on fault voltage ride-through of the new energy station.

This application provides a traveling wave ranging device, distribution terminal, fault monitoring system, and method for distribution networks, relating to the field of distribution network fault monitoring technology. The device includes: a current transformer for acquiring voltage / current traveling wave signals at corresponding detection points; a data processing unit, including: a phase-mode transformation module for performing phase-mode transformation on the voltage / current traveling wave signals to extract the line-mode components of each voltage / current traveling wave signal; a wavelet analysis module for decomposing the extracted line-mode components based on wavelet transform to obtain corresponding wavelet transform coefficients, performing modulus maxima search on all obtained wavelet transform coefficients, and generating a first detection signal representing the detection of the target modulus maxima if a target modulus maxima representing a line fault is determined; and a ranging calculation unit for determining the first fault location information based on the first detection signal. This application enables high-speed sampling and processing of traveling wave data, effectively improving the accuracy of distribution network fault location.

A method of diagnosing a fault in a home appliance may include applying, to a plurality of switches included in an inverter, switching control signals that change on and off states of the plurality of switches; obtaining, through a current sensor, current peak value information about the motor based on the switching control signals; and identifying the fault in the home appliance by applying the obtained current peak value information to a fault diagnosis model that is pre-trained to infer the fault in the home appliance.

There is provided a system and method for determining active and reactive currents during asymmetrical low-voltage ride through (LVRT) conditions at an inverter. The method including: receiving an indication of an LVRT condition; and where the largest phase current magnitude does not exceed a phase current limit, determining a maximum active current for associated positive-sequence and negative-sequence reactive currents by determining a largest active current magnitude and outputting the largest active current and associated positive-sequence and negative-sequence reactive currents to the inverter, otherwise: scaling down each of the positive-sequence and negative-sequence reactive currents, or superimposed positive-sequence and negative-sequence reactive currents, uniformly or non-uniformly to determine revised positive-sequence and negative-sequence reactive currents; where the magnitudes of all of the phase currents are below the phase current limit, determining a non-zero positive-sequence revised active current; and outputting the revised active current and the revised positive-sequence and negative-sequence reactive currents to the inverter.

The application relates to the technical field of power system transformer area management, and specifically discloses a transformer area identification and user binding method based on a special transformer acquisition terminal, which comprises the following steps: separating the harmonic interference generated by the start and stop of electric welders through a kurtosis index and time-frequency energy entropy fusion detection method, and extracting a fundamental wave voltage and a pure power signal; constructing a dynamic time warping model containing phase consistency and gradient feature constraints based on the fundamental wave voltage, calculating voltage trajectory similarity to determine electrical coupling; for users with electrical coupling, fusing dynamic weight power cross-correlation analysis to generate a comprehensive judgment value, combining historical topology change events, and using a space-time graph neural network to update the transformer area topology structure online, so that the dynamic determination of the transformer area to which the user belongs is realized; through multi-dimensional feature fusion and anti-interference algorithm design, the phase shift and waveform distortion problems caused by the electric welder harmonics are reduced, and the transformer area identification accuracy and real-time performance are improved.

The application provides a kind of network construction converter fault current calculation method, device, equipment and storage medium, it is related to network construction converter fault characteristic analysis technical field, method includes: the equivalent circuit model suitable for network construction converter grid-connected system fault current analytical calculation is constructed;Based on the dynamic equation of reactive power-voltage control link of network construction converter, the internal potential analytical expression of network construction converter is solved;The internal potential analytical expression is substituted into the dynamic equation of positive sequence equivalent circuit, and the analytical expression of fault current positive sequence component is solved;Based on the dynamic equation of negative sequence equivalent circuit, the analytical expression of fault current negative sequence component is solved;The analytical expression of fault current positive sequence component and the analytical expression of fault current negative sequence component are superimposed, and the analytical expression of total fault current of network construction converter is obtained.The calculation result of the application is high in accuracy and wide in applicability.