An Integrated High Voltage Energy Metering Device And Its Application In Smart Power Distribution Grid

The information, interactive features of smart grid led to a multi-parameter intelligent, information-based development of electrical equipment. To apply advanced sensor measurement technology, communications technology, information technology on primary electrical equipment for intelligence, and a combination of primary equipment and secondary equipment to enhance the performance, intelligence and information level of electrical equipment is the future smart grid trends.This paper is focus on high voltage energy meter device in lOkV distribution power network. The current energy metering device is composed of power transformers, power meters and middle connection wire links. This combination of varies equipments leads high cost and inconvenience of installation, and the intermediate links easily lead to errors and so affect the measurement accuracy of the results. Therefore this paper aims to develop a new type of integrated energy metering device, which can replace the combinations of conventional power transformers, power meters and their wire connection links. The new device has higher integrated accuracy grade and intelligence level.The paper adopts principle of Faraday cage to make meter circuit working at high voltage level, which can reduce the volume and weight of HVEM to 1/3 of conventional energy meter device. It has characteristics of low power consumption, resource-saving, easy installation, and intelligent information. As the metering device directly connected to high voltage side, and with the same output of power meter, energy data and the energy pulse, it can be called high voltage energy meter (HVEM) in this paper for the sake of description convenience. The HVEM has higher integrated accuracy grade, and with the meter circuit working at high voltage side, it can basically eliminate electricity stealing behavior at the low voltage side. The widely application of HVEM can increase the measurable point in distribution network, which help people perceive state of power network and improve its efficiency.This paper describes the principle of HVEM, and key issues in development process. Such as material selection of capacitor voltage transducer, inner and outer insulation of device, how to acquire the working power at high voltage and how to transmit data to ground potential from high voltage.The accuracy grade of novel HVEM must be defined by integrated error calibration system. The conventional energy meter devices are calibrated by corresponding standard separately, then derived an estimated error from complex error formula. Based on the conventional principle of standards traceability, this paper developed novel measurement standards, and had carried on its error analysis. The measurement standards can not only be able to calibrate HVEM, but also the conventional power metering device.The novel HVEM is directly used on high voltage power line, the same working condition with power transformer and energy meter. Reference to the state standards of power transformer and power meter, this paper researched tests methods, such as reliability, accuracy test and environmental test, and analyzed data of tests results. It also analyzed and estimated field testing results of HVEM.Finally, the paper describes the special application in the intelligent power grid. In addition to replace conventional measuring device, the HVEM can be used as "integrated metering standards". Therefore, in addition to replace conventional meter device, the HVEM can be used as on-line monitoring metering standards for important customer. It also can be applied as metering device on high voltage power line, which constitutes a hierarchical anti-theft system with low voltage customer meters, to facilitate positioning of stealing behavior.