Application And Realization For Online Automatic Verification And Calibration System Of Verification Device Of Electrical Energy Meter

Electrical energy meter is compulsory verification instruments to measure electrical energy used by customers of the whole society according to national regulations and its accuracy need to be tested by Verification Device of Electrical Energy Meters (hereinafter to be referred as "Device"). The accuracy and reliability of Device should be tested by Device Verification System (hereinafter referred to as the "System") in accordance with the national verification regulation of Verification equipment for AC electrical energy meters (No.JJG597-2005). Therefore, the components and application of System is focus of metrological services.For many years, verifications to Device with artificial manual operation System have not been adapted to the development of metrological services in our country. According to national regulations of verification at present, too many items are requested and most processes of operation are complicated. At same time, owing to huge size, Device can not be sent to the laboratory and it was always verificated in the place of itself. Moreover, it needed a long time to complete the whole verification process because a great deal of original data needed to be recorded and calculated and then verification certificate would be worked out finally. And it is difficult for manual verification to reach to request of regulations due to inevitable error from the person. Now, more and more devices are sent to the provincial-level metrological service institution to verify and artificial manual operation system has affected the whole work process gravely. For above reasons, it is urgent to realize to automatic check and adjustment operation to improve the quality, the efficiency and the level of verification. Therefore, a research on design and application of the automatic System is carried out to provide valuable information to automatic metrology study in our country.Firstly, the necessary components of System were chosen according to national regulation items and their requirements. Modular design was adopted for System hardware and the main hardware included test standard device, supplementary equipments, the Device and the notebook computer. Among them, notebook computer was the core controller in order to control the whole detection. The core of test standard device was A/D transform technology and Digital Signal Processor (DSP) technology. Furthermore, built-in microprocessor was the core controller in order to exchange data with DSP. According to different signal, different cables between hardware were applied and different connection styles were also used in accordance with different test items. After repeated use, it was found that the System measurement accuracy was 0.02%, which meant the design requirement had been meet.Secondly, relevant software was developed according to hardware in the System. This software adopted VB6.0 as platform, because VB6.0 was widely used to make software interface. This software made use of modular programming method, in which included the error test module, instrument communication and control module, data management module and certificate module. After times of effort, this software fulfilled purposes to the entire site verification process. It can be used for data collection, recording, processing, reporting, storing and searching.Finally, we conducted assessment many times to ensure the System's accuracy and reliability. It was showed that the total expanded uncertainty was up to 0.014%. That meant the System could achieve design requirements due to small error.The completion of this project could help automatic verification of Device in metrological services in Shandong Province, which could ensure the accuracy, reliability, speed and efficiency of electricity transmission value in our province. In addition, the automatic System would also help to establish electrical energy meter testing equipment files, to manage and query easily, to provide basis for verification cyclically. To some extent, this automatic System promoted development of electrical energy metrology in Shandong province and neighborhood provinces, and protection of electrical energy meter quality before it was shipped from factory. It could reduce electricity disputes, safeguard the legitimate rights and interests, and improve electrical energy efficiency with obvious social and economic benefits.