Abstract: The invention discloses a method and system for identifying an element parameter and a power correction factor of an electric power system. The method comprises: inputting an active power telemetering steady state value {circumflex over (P)}, a reactive power telemetering steady state value {circumflex over (Q)}, and a voltage telemetering state value Û of a power grid with n elements, to establish P+jQ={circumflex over (P)}+j{circumflex over (Q)}+G(?,{circumflex over (P)},{circumflex over (Q)}) for telemetering power, where G(?,{circumflex over (P)},{circumflex over (Q)}) is power correction function regarding {circumflex over (P)} and {circumflex over (Q)}, and ? is power correction factor; establishing F(Y,P,Q,Û)=0, where Y is an admittance matrix of the n elements; setting F(Y,P,Q,Û)=? and J=?T·?, minimizing J, and determining Y and ?; restoring element parameters including resistance R, reactance X and susceptance B from Y; and outputting R,X,B and ?.

Abstract: The invention discloses a method for identifying full parameters of an electric element by a fault recording data, comprising steps: inputting fault recording data related to an electric element; conducting data processing on the fault recording data; identifying full parameters of the element by intercepted data and a differential equation of the full parameters of the element; and outputting an identified result. Further proposed are a system for identifying full parameters of a power generator by fault recording data and a method for locating a line fault point with fault recording data. With the implementation of the invention, a fault resistance and full parameters of an element such as an electric line and a transformer, etc. can be identified. The invention can obtain full parameters of a fault element and also a non-fault element, and the parameters precision would be increased from the current 20% to less than 1%.

Abstract: An apparatus for AC physical signals measurement and data acquisition and the method for the same are provided. The apparatus for AC physical signals measurement and data acquisition comprises an analog sampling channel for inputting an AC signal and outputting an analog sampling value; a sampling switch for performing re-sampling to obtain data frequency as required by the receiving side; a register for storing a re-sampling value from the sampling switch; a bus for outputting the re-sampling value in the register to the receiving side; a timing controller for controlling the analog sampling channel and the re-sampling frequency of the sampling switch; and a digital low-pass filter, which has an input connected with the analog sampling value outputted by the analog sampling channel and an output connected with the sampling switch, filters out high frequency components from the sampling value, and has a cut-off frequency that should be lower than 0.5 times the re-sampling frequency of the sampling switch.

Abstract: The present invention relates to a data sampling method: sampling a physical quantity according to a sampling frequency fs?fsh, fsh=?max/? being the upper limit of the sampling frequency; and a data sampling method and system: sampling a physical quantity with a sampling frequency satisfying Nyquist theorem, firstly performing low-pass filtering on an obtained sampled sequence, and then re-sampling, the re-sampling frequency fs??max/?, where ? is the Z-domain error of a sampling system, and ?max the maximum error of an S-domain. The present invention also relates to a parameter identification method and system which firstly adopt the above data sampling method and system to obtain sampled data, and then utilize the sampled data to perform dynamic and/or static parameter identification.

Abstract: The invention discloses a method and system for identifying an element parameter and a power correction factor of an electric power system. The method comprises: inputting an active power telemetering steady state value {circumflex over (P)}, a reactive power telemetering steady state value {circumflex over (Q)}, and a voltage telemetering state value Û of a power grid with n elements, to establish P+jQ={circumflex over (P)}+j{circumflex over (Q)}+G(?, {circumflex over (P)}, {circumflex over (Q)}) for telemetering power, where G(?, {circumflex over (P)}, {circumflex over (Q)}) is power correction function regarding {circumflex over (P)} and {circumflex over (Q)}, and ? is power correction factor; establishing F(Y,P,Q,Û)=0, where Y is an admittance matrix of the n elements; setting F(Y,P,Q,Û)=? and J=?T·?, minimizing J, and determining Y and ?; restoring element parameters including resistance R, reactance X and susceptance B from Y; and outputting R,X,B and ?.

Abstract: The invention discloses a method for identifying full parameters of an electric element by a fault recording data, comprising steps: inputting fault recording data related to an electric element; conducting data processing on the fault recording data; identifying full parameters of the element by intercepted data and a differential equation of the full parameters of the element; and outputting an identified result. Further proposed are a system for identifying full parameters of a power generator by fault recording data and a method for locating a line fault point with fault recording data. With the implementation of the invention, a fault resistance and full parameters of an element such as an electric line and a transformer, etc. can be identified. The invention can obtain full parameters of a fault element and also a non-fault element, and the parameters precision would be increased from the current 20% to less than 1%.

Abstract: The present invention relates to a data sampling method: sampling a physical quantity according to a sampling frequency fs?fsh, fsh=?max/? being the upper limit of the sampling frequency; and a data sampling method and system: sampling a physical quantity with a sampling frequency satisfying Nyquist theorem, firstly performing low-pass filtering on an obtained sampled sequence, and then re-sampling, the re-sampling frequency fs??max/?, where ? is the Z-domain error of a sampling system, and ?max the maximum error of an S-domain. The present invention also relates to a parameter identification method and system which firstly adopt the above data sampling method and system to obtain sampled data, and then utilize the sampled data to perform dynamic and/or static parameter identification.

Abstract: Provided is a method for acquiring continuous physical signal such as temperature, pressure and the like. The method comprises the following steps: inputting a voltage signal u representing continuous physical signal; obtaining a sampled signal uk of an analog voltage through an analog sampling channel (1), wherein the sampling frequency is f?h; performing digital low-pass filtering on the uk (6) to obtain a voltage signal ?k subjected to low-pass filtering, and resampling the ?k to obtain a resample signal ?j, wherein the resampling frequency f?y is the same as the sampling frequency required by an application terminal and the sampling frequency f?h is M times of the resampling frequency f?y; and storing and outputting the resample signal ?j to the application terminal. Provided also is a corresponding device.

Abstract: The invention discloses a measuring device and a measuring method for a continuous physical quantity. The measuring device comprises a timing unit for outputting a time base and a time scale; a sampling unit for sampling the continuous physical quantity under control of the time base and at time intervals that meet the Nyquist sampling theorem, and outputting a sampling value; a decision unit for deciding whether the sampling value turns into a transient state from a steady state or turns into the steady state from the transient state; a calculating unit for calculating a steady state value for the sampling value of the sampling unit in the steady state; and an output unit for outputting the start time of the steady state and the steady state value X, and the start time and the sampling value of the transient state according to the result of decision and the time scale. The invention may not only avoid the aliasing and but also reduce the output data volume.

Abstract: Provided is a method for acquiring continuous physical signal such as temperature, pressure and the like. The method comprises the following steps: inputting a voltage signal u representing continuous physical signal; obtaining a sampled signal uk of an analog voltage through an analog sampling channel (1), wherein the sampling frequency is f?h; performing digital low-pass filtering on the uk (6) to obtain a voltage signal ?k subjected to low-pass filtering, and resampling the ?k to obtain a resample signal ?j, wherein the resampling frequency f?y is the same as the sampling frequency required by an application terminal and the sampling frequency f?h is M times of the resampling frequency f?y; and storing and outputting the resample signal ?j to the application terminal. Provided also is a corresponding device.

Abstract: An apparatus for AC physical signals measurement and data acquisition and the method for the same are provided. The apparatus for AC physical signals measurement and data acquisition comprises an analog sampling channel for inputting an AC signal and outputting an analog sampling value; a sampling switch for performing re-sampling to obtain data frequency as required by the receiving side; a register for storing a re-sampling value from the sampling switch; a bus for outputting the re-sampling value in the register to the receiving side; a timing controller for controlling the analog sampling channel and the re-sampling frequency of the sampling switch; and a digital low-pass filter, which has an input connected with the analog sampling value outputted by the analog sampling channel and an output connected with the sampling switch, filters out high frequency components from the sampling value, and has a cut-off frequency that should be lower than 0.5 times the re-sampling frequency of the sampling switch.

Abstract: The invention discloses a measuring device and a measuring method for a continuous physical quantity. The measuring device comprises a timing unit for outputting a time base and a time scale; a sampling unit for sampling the continuous physical quantity under control of the time base and at time intervals that meet the Nyquist sampling theorem, and outputting a sampling value; a decision unit for deciding whether the sampling value turns into a transient state from a steady state or turns into the steady state from the transient state; a calculating unit for calculating a steady state value for the sampling value of the sampling unit in the steady state; and an output unit for outputting the start time of the steady state and the steady state value X, and the start time and the sampling value of the transient state according to the result of decision and the time scale. The invention may not only avoid the aliasing and but also reduce the output data volume.

Abstract: A system and method for measuring phase-angle in electrical power systems includes inputting a reference signal into a receiving terminal of a communication system at a reference station and then sending the reference signal through the communication system. The reference signal is received at a substation and shaped as a quasi-reference signal. A phase difference .beta. between the quasi-reference signal and a tested signal at the substation is then measured. Phase delay of the reference signal caused by the communication system, including phase delay produced from sending means, receiving means, relaying units, and communication channels, is calculated. A phase difference .alpha. is then calculated between the reference signal and the tested signal according to the phase difference .beta. between the quasi-reference signal and the tested signal and the phase delay of the reference signal caused by the communication system.