Magnetizing inrush current recognition method and recognition device
A technology of excitation inrush current and identification method, which is applied in measurement devices, measurement of current/voltage, measurement using digital measurement technology, etc., can solve the problems of many influencing factors of second harmonic measurement, insufficient identification accuracy, and high hardware requirements, Achieve good engineering application prospects, improve accuracy and reliability, and achieve the effect of less measurement data
Active Publication Date: 2018-03-06
CHINA ELECTRIC POWER RES INST +2
View PDF9 Cites 6 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
[0006] In order to overcome the disadvantages of insufficient identification accuracy in the existing excitation inrush current identification technology, many factors affecting the second harmonic measurement, and high hardware requirements for the discontinuity angle measurement, the present invention provides a method based on the attenuation characteristics of the harmonic distortion rate of the transformer current. The excitation inrush current identification method can accurately distinguish the fault current and excitation inrush current of the transformer, so as to ensure the correct rate of transformer differential protection action
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment
[0099] Such as figure 2 The simplified wiring diagram of the two-terminal network shown is for a rated voltage of In the UHV three-winding transformer, the characteristic difference between the short-circuit current when a three-phase short-circuit fault occurs on the 500kV side and the excitation inrush current when the 500kV side is closed and no-load main transformer is simulated and calculated, and the transformer-based transformer proposed by the present invention is analyzed. The application effect of the excitation inrush current identification method based on the attenuation characteristics of the current harmonic distortion rate. The circuit breakers on the 1000kV side and 500kV side of the transformer are not equipped with closing resistors.
[0100] The typical waveform schematic diagram of the excitation inrush current when the main transformer is closed and no-load and the short-circuit current when the transformer outlet is faulty is obtained by the simulatio...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention provides a magnetizing inrush current recognition method and recognition device. The magnetizing inrush current recognition method comprises setting a time interval reference; calculating the total harmonics distortion of current through an outlet breaker at the high-voltage and medium-voltage sides of a transformer; carrying out logical judgment on current data of the transformer outlet breaker, identifying magnetizing inrush current and fault current, and ensuring the correct rate of transformer differential protection operation. The magnetizing inrush current recognition device comprises a digital simulation unit, a current measuring unit, a data processing unit, a criterion making unit and an identification unit. According to the technical scheme, less measured data is needed, and the magnetizing inrush current recognition method and recognition device are simple and easy to implement, three phases are independently discriminated, restraint is carried out according tothe phases without being affected by saturation of a current transformer, correct operation of transformer differential protection is ensured, and the magnetizing inrush current recognition method and recognition device are reliable and effective in an application scene that the transformer outlet breaker is not provided with a closing resistor.
Description
technical field [0001] The invention relates to the field of excitation inrush current identification, in particular to an excitation inrush current identification method and an identification device. Background technique [0002] As one of the core components of EHV and UHV transmission systems, transformers have high requirements on the reliability and quickness of their main protection. For a long time, the correct operation rate of transformer protection has been low. For the commonly used transformer differential protection at present, the excitation inrush current is an important reason for its incorrect operation. How to prevent the excitation inrush current from causing malfunction is one of the important research topics of transformer protection. . [0003] At present, the differential protection of transformers in field operation mainly adopts the principle of second harmonic braking and the principle of discontinuity angle to identify the inrush current, and the ...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More IPC IPC(8): G01R19/25
CPCG01R19/2506
Inventor 郑彬项祖涛班连庚滕文涛周佩朋李岩军韩亚楠杜宁王晓彤
Owner CHINA ELECTRIC POWER RES INST