A non-intrusive load monitoring method based on V-I trajectory and neural network includes: collecting the household voltage, current and active power data in real time; determining whether there is a switching event and whether the load operating state has reached a steady state through the change of the active power; obtaining the voltage, current and power data of the load, converting the V-I trajectory into RGB color image containing the phase difference between the voltage and current, power and other information. After obtaining the RGB color image, performing normalization processing and performing load monitoring through pre-trained convolutional neural network. The present disclosure fully extracts the steady-state feature of the load through the convolutional neural network, and the neural network model can directly run on an embedded device, and does not need to rely on the computing support of a server.

A method for detecting non-technical losses in an electrical power system includes measuring an area under a squared RMS current curve for a power cable in the electrical power system over at least one time interval, measuring an active and a reactive energy for the power cable over the at least one time interval, and characterizing a cable reactance and a cable resistance using the active energy, the reactive energy, and the area under the squared RMS current curve. The method further includes determining an active energy loss and a reactive energy loss over the at least one time interval using the area under the squared RMS current curve and the reactance and the resistance of the cable, and detecting a non-technical loss in the electrical power system based on the active energy loss and the reactive energy loss over the at least one time interval.

A device for testing a power module of a set of power modules connected together includes reactive power compensation means capable of compensating the reactive power transferred between a tested power module and the other power modules, and means for monitoring the power generated by the tested power module including means for comparing said generated power with at least one threshold value.

A method for identifying a location of a fault in an electrical power distribution network that includes identifying an impedance of an electrical line between each pair of adjacent utility poles, measuring a voltage and a current of the power signal at a switching device during the fault, and estimating a voltage at each of the utility poles downstream of the switching device using the impedance of the electrical line between the utility poles and the measured voltage and current during the fault. The method calculates a reactive power value at each of the utility poles using the estimated voltages, where calculating a reactive power value includes compensating for distributed loads along the electrical line that consume reactive power during the fault, and determines the location of the fault based on where the reactive power goes to zero along the electrical line.

The invention relates to an electrical energy meter comprising a current-measuring circuit and a voltage-measuring circuit, the current-measuring circuit comprising a current sensor producing a first analog measuring voltage and a first analog-to-digital converter arranged so as to carry out a first sampling of the first analog measuring voltage in a such a way as to produce first digital values, and the voltage-measuring circuit comprising a voltage sensor-producing a second analog measuring voltage and a second analog-to-digital converter arranged so as to carry out a second sampling of the second analog measuring voltage in such a way as to produce second digital values, the electrical energy meter also comprising a first synchronization circuit arranged so as to synchronize the frequency of the first sampling and the second sampling.

The invention relates to an electrical energy meter comprising a current-measuring circuit and a voltage-measuring circuit, the current-measuring circuit comprising a current sensor producing a first analog measuring voltage and a first analog-to-digital converter arranged so as to carry out a first sampling of the first analog measuring voltage in a such a way as to produce first digital values, and the voltage-measuring circuit comprising a voltage sensor-producing a second analog measuring voltage and a second analog-to-digital converter arranged so as to carry out a second sampling of the second analog measuring voltage in such a way as to produce second digital values, the electrical energy meter also comprising a first synchronization circuit arranged so as to synchronize the frequency of the first sampling and the second sampling.

The invention provides reactive power control equipment that controls the reactive power adjusted by a synchronous condenser coupled to an electric power grid and the reactive power of the electric power supplied to the electric power grid, to optimally control the reactive power in each load terminal point (power consumption area), considering instability of the electric power supplied from renewable energy power generation equipment. The above equipment includes an input portion that inputs information of reactive power including reactive power adjusted by an automatic voltage regulator of automatically adjusting a voltage of electric power generated by an electric power generator and supplied to an electric power grid, reactive power adjusted by a synchronous condenser coupled to the electric power grid, reactive power of electric power generated by the renewable energy power generation equipment, and reactive power set in each load terminal point (consumer area) of consuming the electric power; a calculation unit that calculates each setting value of reactive power adjusted by the synchronous condenser and the automatic voltage regulator, using the information of the reactive power input in the input portion; and an output portion that outputs the setting values of the reactive power calculated by the calculation unit respectively to the synchronous condenser and the automatic voltage regulator.

A method for identifying a location of a fault in an electrical power distribution network that includes identifying an impedance of an electrical line between each pair of adjacent utility poles, measuring a voltage and a current of the power signal at a switching device during the fault, and estimating a voltage at each of the utility poles downstream of the switching device using the impedance of the electrical line between the utility poles and the measured voltage and current during the fault. The method calculates a reactive power value at each of the utility poles using the estimated voltages, where calculating a reactive power value includes compensating for distributed loads along the electrical line that consume reactive power during the fault, and determines the location of the fault based on where the reactive power goes to zero along the electrical line.

Various embodiments are provided for conducting a power flow analysis using a set of line-wise power balance equations. In at least some embodiment, the set of line-wise power balance equations is solved using a Newton-Raphson technique. In various cases, the Jacobian matrix generated by the Newton-Raphson technique may directly indicate the transmission lines, or sets of transmission lines, which are most susceptible to voltage collapse. In at least one example application, the set of line-wise power balance equations may be used as equality constraints in an optimal power flow (OPF) formulation for solving an optimal power flow (OPF) problem.

In a power system voltage reactive power monitoring control device, a balance between the power system voltage and the reactive power can be maintained even when, for example, the output of renewable energy varies over time due to the weather, or the power supply configuration or system configuration changes, and the economic efficiency can be improved. In the power system voltage reactive power monitoring control device, which supplies transmission data to individual devices capable of adjusting the voltage and the reactive power of a power system, indices indicating the stability of the power system are used to determine one or more target value restrictions, information about the target value is obtained from the target value restrictions, transmission data containing information about the target value is supplied to the individual devices, and the voltage and reactive power at the relevant installation site are adjusted by the individual devices.