High Accuracy Light Wide Area Measurement Device And System Of Power System

Wide area measurement technique is one of the key research areas on smart grid technology, which can achieve real-time dynamic information and static information at the same time. This technique provides conditions for interval dynamic monitoring control and analysis of the power system, and improves the power system monitoring from a steady-state stage to the dynamic-state stage. With the distributed access of the new energy, power supply points of the electric distribution network are increased, and their dynamic behaviors become increasingly complex. It is vital important to improve the intelligence level of the power grid that expanding the power grid monitoring tools and building panoramic synchronous dynamic monitoring system.In this paper, hardware devices and software development of the high-precision Wide Area Measurement System Light (WAMS Light) of power system are studied. On the condition of the actual situation of China’s power grid, as well as the lack of the WAMS and its Phasor Measurement Unit (PMU), the high-precision and multi-mode PMU Light is designed and developed. It can be installed on the low voltage user side directly, for its convenient installation, maintenance, and low cost. High-precision secondary adaptive data reconstruction frequency algorithm and dual-core microprocessor hardware architecture that the PMU Light use, effectively solved the spectral leakage problem of the conventional Discrete Fourier Transform algorithm (DFT). It significantly improved the measuring accuracy, stability and real-time performance of the PMU Light in a wider range of frequency offset. Multi-mode data transmission can customized select mature wired Internet, GPRS/3G wireless or serial communication, which makes the network more flexible and easier. Dual-mode mutual standby prepare timing system uses GPS and Beidou navigation system spare each grant, which has important strategic significance for synchronous data acquisition and control. PMU Light integrates the operating system in industrial computer, and makes the device in situ implement real-time display of images, on-line analysis and early warning. It enhances the coordination and interaction between the measuring end and the master server. Through the device’s actual performance tests, it is verified that the accuracy, instantaneity and stability of PMU Light are improved significantly over the DFT algorithm in PMU.The application of the high-precision PMU Light, explores the coupling and characterization between various levels information of power system, and extends Wide Area Measurement connotation. The only one set of WAMS Light is a useful supplement to the existing power grid dynamic monitoring system, which fills the gaps in the wide-area synchronized measurements of low-voltage side study in China. It achieves many functions such as frequency safety assessment, monitoring and early warning of low frequency oscillation line, which can be used for analysis of frequency response, checking the validity of the numerical simulation, and the state estimation of distribution network. It will be upgraded to three-phase PMU Light in the next step, adding modules like precision power, current phasor measurements, new energy grid tracking, and so on. The three-phase PMU Light will provide theoretical and applied foundation for the system impressive panoramic control of smart grid systems.