Research On A High-precision3-phase Multi-functions Industrial Power Meter

With the coming of the21st century, the economy of our country enters a rapid development stage, which pushes the research on a high-precision3-phase multi-functions industrial power meter to an exciting climax. On the one hand, in current domestic market, the multi-functions industrial power meter bases only on a single chip, which has many problems such as poorly match, slowly and no reliable data communication, low precision and as well as many defects exist in EMC. On the other hand, the fast transient burst compatibility should also be improved. However, the power meter from the foreign market which performs the similar functions has a stable performance and high price. So our research and development of3-phase high-precision multi-functions industrial power meter which bases on the dual-core scheme of high performance ARM processor and special measure integrated chip is very meaningful.Therefore, we study and explore this high-precision3-phase multi-functions industrial power meter which bases on STM32F207ZE of ST as a control heart and ADE7880of Analog Device Instrument as a measure heart. The measurement of this electrical energy accuracy can reach0.2S, the error voltage of current and frequency is less than0.1%, the harmonic accuracy reaches Class A, the error voltage of three-phase imbalance degree is less than0.2%, the error current of three-phase imbalance degree is less than0.1%and the error clock is less than0.1s per day. This system fits the standards of DL/T645-2007multi-function watt-hour meter communication protocol and supports two RS485interfaces independently. At the same time, it meets the standards of GB/T19862-2005power quality monitoring equipment general requirements. The design of this project of an upgraded version of dual-core high-precision three-phase multi-functional industrial power meter is in mass production now and it has passed the certification of Electrical and Instrument of Harbin Institute. The main work of this paper includes:1. Firstly, we study the background and trends of watt-hour meter, including electric energy metering chip at home and abroad. Then, we analyze the principle of the meter measurement and propose the design scheme of this paper.2. We discuss the part of the hardware of high-precision3-phase multi-functions industrial power meter. Firstly, we sketch out the product feature of ADE7880and its principle of metering. Then we plan and design the hardware schematic diagram of the whole system, including the design of power supply circuit, measurement circuit, main control circuit etc. After that, we plan of the structure of the whole system, select components of the encapsulations and the terminal specifications, complete the layout of PCB. Finally, we assemble the entity by welding the all parts.3. We discuss the part of software design of high-precision three-phase multi-functions industrial power meter, including introducing the development environment of system software, planning of the design process of system software, and the distribution of its related parameter addresses.4. We discuss the testing and calibration of the3-phase high-precision multi-functions industrial power meter. Firstly, we introduce the commonly used calibration methods of3-phase industrial power meter. Secondly, we analyze the high efficient calibration method of power meter. Finally, we describe the whole testing of power meter, including the functional testing, the accuracy testing and the electrical performance testing etc. On this basis, we search for the mistakes and make the correction of the hardware and software parts.