ABSTRACT
China has implemented large-scale transformation and construction to the grid in recent years, thus cause a large number of dedicated users increase continuously, and strengthen the management of electricity enterprises.[1-6] The concepts of improving power quality and realizing the energy saving and consumption reducing is paid more and more attention, as a result, the multifunctional intelligent electric meters have been widespread attention and application.[7-13]
So, a portable three-phase smart electric meter based on dual AVR and ATmega128L is presented in this paper. The meter utilizes two ATmega128L MCUs as its control core and makes full use of their rich on-chip resources and peripheral equipment, thus can real-time monitor, record, display and large store big users’ three phase voltage, current, active power, reactive power, apparent power, power factor and other electrical parameters which exist in low voltage side of users’ distribution system, meanwhile, the use of Zigbee wireless communication mode[14] realizes that the measurement data are uploaded on time to the upper software and which makes real-time comprehensive power quality treatment analysis. The software is designed based on Matlab and according to China’s power quality standards; it makes corresponding analysis with the data transmitted through Zigbee, and puts forward the improvement scheme, which can effec-
Smart meters put forward in this paper are connected to low voltage side of large users, threephase voltage and current signal and zero phase voltage and current signal from big users’ measuring lines are sampled in the way of instantaneous synchronous by the chip MAX125, and this data sampling process is controlled by 1# ATmega128L, such as real-time tracking frequency signal, synchronous A/D conversion control, voltage and current channel magnification control, and so on. 2# ATmega128L receives sampling data from 1# ATmega128L through SPI synchronous serial communication interface, then implements a series of calculations on these data. On one hand, these data are displayed by LCD module and stored by SD card; on the other hand, the Zigbee Control Module in the Zigbee wireless communication unit is controlled by 1# ATmega128L to receive and send data to the power quality comprehensive management and real-time simulation platform based on Matlab, and this platform utilizes the powerful data analysis functions of Matlab to implement effective distribution management and power quality improvement analysis on the big electricity dedicated users.
