Creativity without limit, instrument inventions. Today to introduce a national invention patent - a digital energy meter on-line monitoring and evaluation system and methods. The patent by the Guizhou Electric Power Research Institute application, and in the May 10, 2017 was authorized notice.
Content description
The present invention relates to the field of energy metering test technology, and more particularly to a digital meter monitoring and evaluation system and method. The same time as
Background of the invention
With the increasing development of digital power system, digital metering system has been more and more widely used. As an important part of the digital metering system, the demand for digital energy meters is also growing. The input signal of the digital energy meter is an all-digital signal which is collected by the electronic current and voltage transformer and transmitted to the merging unit according to IEC61850-9-1 or IEC61850-9-2 communication protocol. Digital energy meter on the input current, voltage digital signal logic operation, in theory, there is no error in its active energy measurement. But in fact due to sampling accuracy, processor word length and time synchronization and other factors, the error must exist. In the actual operation of what factors on the digital energy meter measurement error greater impact in the face of extreme conditions such as a large number of high-frequency harmonics in the case of whether the normal operation of digital energy meter, digital meter abnormal event records Work reliability and other issues, are the need to study the object. Digital energy meter is still in the development stage, its test methods, the value of transmission, error judgments and reliability, there is no uniform standard, which to the development of digital energy meter and large-scale application has brought great obstacles. The same time as
At present, digital standards have not yet published national standards and verification procedures, and the existing research are for digital energy meter on-site verification, did not mention the working state of digital energy meter long-term, online real-time monitoring and evaluation , For example, the patent number 201210545604 .5 patent "a digital input type energy meter online calibration device" mentioned in the digital energy meter online verification methods and equipment. And the current research is mainly the detection of the measurement error of the targeted digital energy meter, for example, the patent number 201210447903 .5 patent "a digital energy meter accuracy assessment system and its method" describes a digital Energy meter for field testing methods, but also to simulate the message dropped frames, network storms and other abnormal state, the detection of digital energy meter creep, start and harmonic effects, but not concerned about the digital meter abnormal event logging The "Digital energy meter special requirements" clearly stipulates that the digital energy meter should have the power grid abnormal event recording function. The same time as
The contents of the invention
SUMMARY OF THE INVENTION In view of the above technical problems, it is an object of the present invention to provide a system for on-line monitoring and evaluation of a digital electric energy meter, which performs on-line monitoring of an actual running digital energy meter. Through the data analysis and comparison, to monitor the digital meter energy measurement error and event recording function reliability. The same time as
The present invention provides a digital energy meter on-line monitoring and evaluation system comprising: a merging unit for transmitting data to a plurality of digital electric energy meters and the remote computer through the switch, wherein the data comprises a voltage digital signal And a current digital signal; a switch for converting data outputted from a port of the merging unit into multiplexed data and outputting the multiplexed data to the plurality of digital power meters and the remote computer; and RS485 The hub collects the energy value and the abnormal event record of the plurality of digital electric energy meter metering and sends the data to the remote computer.
The remote computer receives the data from the switch, analyzes the voltage and current values by the FFT transform and sends it to the local computer, and analyzes whether or not a grid abnormality event occurs and stores the power grid abnormality event, and also outputs the data from the RS485 hub Obtaining said electric energy value of said plurality of digital energy meter metering and said abnormal event recording and storing. The same time as
Data transmission unit: communicating the parsed voltage, current value, the grid abnormality event, the electric energy value measured by the plurality of digital energy meters, and the abnormal event recording in the remote computer The network is sent back to the local computer; and the local computer: calculating the electric energy value based on the parsed voltage and current values returned in the remote computer, and calculating the calculated electric energy value in each metering period The plurality of digital electric energy meters are analyzed and the long-term on-line operation measurement error of the plurality of digital energy meters is analyzed; and the power consumption of the plurality of digital energy meters is also calculated based on the power consumption anomalies recorded in the remote computer And comparing the reliability of the long-term running event recording function of the plurality of digital power meters with the grid abnormality event records recorded by the plurality of digital power meters, respectively. The same time as
The invention has the following advantages compared with the prior art by the invention as compared with the prior art: The invention realizes the influence factors of the measurement error of the digital energy meter by data analysis and comparison, and promotes the digital energy meter correlation The standard as soon as possible the introduction and improvement; set the digital energy meter to be assessed at regular intervals to ensure that the digital meter to return the data for the same time point data, to avoid the return of data due to time synchronization caused by the error, The local computer analysis by the remote computer FFT analysis of the current and voltage data to determine whether the occurrence of abnormal events, and then digital meter to record the number of abnormal events to compare the analysis of digital energy meter The reliability of the abnormal event record, the promotion of electronic transformer and digital energy meter and other new energy measurement equipment in the digital substation energy metering system application, effectively solve the digital substation energy metering equipment, daily operation and maintenance and energy measurement long-term precision, reliable Sexual problem.