Electric energy measurement method and device suitable for three-half wiring of intelligent substation

Abstract

The invention relates to an electric energy measurement method suitable for three-half wiring in an intelligent substation, comprising: sampling intervals divided by three-half wiring, high-speed acquisition of busbar voltage, middle switch current and side switch current, and The merging unit directly transmits point-to-point transmission to the digital electric energy meter; forwards it through the physical layer of the optical fiber sending port; judges the synchronization state of the merging unit, and selects an appropriate synchronization method for synchronous sampling; The third is the power of the wiring; finally, the power information is output through the MMS message. The invention also discloses an electric energy metering device suitable for three-half wiring of an intelligent substation. The invention avoids that the stability of the network transmission of the sampled value affects the measurement accuracy of three-half of the wiring electric quantity, reduces the dependence of the multi-interval measurement on the clock synchronization system of the total station, increases the synchronization fault tolerance of the digital electric energy meter, and improves the reliability of the overall electric energy measurement. .

Description

technical field [0001] The invention relates to the technical field of measurement of intelligent substations in power systems, in particular to a method and device for measuring electric energy suitable for three-half wiring of intelligent substations. Background technique [0002] The smart substation adopts digital transmission of electrical sampling information, which effectively curbs the repeated configuration of the acquisition equipment, improves the flexibility of information transmission in the substation, and enhances the data interaction and processing capabilities of the substation, but it also complicates the identification of the information relationship and function of the substation. To a certain extent, it increases the difficulty of implementing the on-site work of the substation. [0003] The three-half wiring is composed of three circuit breakers connected in series between the bus bars and two outgoing lines. It has high power supply reliability and ope...

AI Technical Summary

Problems solved by technology

The sampling value network is implemented based on network switches. When the switches work abnormally, data loss points or excessive transmission delays will occur, which will affect the reliability of energy metering.

In particular, the network pressure problem will be introduced after the sampling value network is transmitted. When the network design is unreasonable, the transmission load is heavy, or the network equipment is abnormal, a large number of invalid Ethernet interference messages may be generated in the sampling value network, affecting the switch. The data processing capability even leads to the paralysis of the sampling value network, and the electric energy cannot be measured

[0006] (2) Heavily dependent on the clock synchronization system of the whole station

The reliability of the clock synchronization source, the communication stability of the synchronization optical fiber, and the accuracy of the synchronization algorithm inside the merging unit may affect the synchronization of the sampled data

When the synchronization system in the station fails, the energy meter cannot reliably obtain the required sampling value, and there are certain defects in the realization principle

[0007] (3) The technical advantages of digital metering in smart substations are not fully utilized

In the current digital electric energy metering system, the connection between the electric energy meter and the station control layer of the substation is mainly realized by the DL / T 645 protocol of the traditional RS485 connection. This communication mode is simple to implement, but the data transmission is slow; Sampling, data conversion will lose accuracy; lack of information optimization for the characteristics of equipment at the process level of smart substations, and cannot accurately reflect the abnormal state of digital sampling value transmission

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