The Development Of PMU Dynamic Performance Detector

The scale of interconnected power grid is growing in our country; the interconnection of nation’s power grid has brought huge challenge to the safe, stable and reliable operation of power system. The synchronized phasor measurement unit(PMU) as the basic unit to the wide area measurement system(WAMS), do a comprehensive and accurate real-time monitoring to the running state on the key point of the whole power grid, provides important guarantee for the safe and stable operation of the whole interconnected power grid. The data quality collected by PMU directly affects the wide-area monitoring master station system analysis the accuracy and effectiveness of the control results, therefore PMU must be tested periodically after be installed, in order to ensure that its performance is good, and can continue to effectively and reliably monitor the power grid.The PMU dynamic performance detector designed by this topic can roundly and effectively detect the PMU device’s dynamic performance, including harmonic influence, amplitude modulation, frequency modulation, analysis of low frequency oscillation and step response under the PC software operation. Detector adopts an architecture with double DSP, while DSP1 complete the work, including network communication, receive GPS message as well as the main control function, and DSP2 is used to generate cosine waveform, harmonic waveform, amplitude modulation waveform, frequency modulation waveform and the simulation waveform. The whole detector is consist of the communication control module, waveform generation module, GPS receiver module, high-speed power amplifier module, acquisition module and the overload protection module. Communication control module uses the Ethernet controller CS8900 A to communicate with network, receives various instructions and parameters send by PC; gets time information via a serial port receives the GPS message; completes the data interaction between the double DSP by using dual port RAM.Waveform generation module uses GPS second pulse(1 PPS) as synchronizing signal, gets cosine waveform data by looking table, and outputs analog signal through a 16 bits digital to analog conversion chip DAC8820. The weak signal produced by waveform generation module can output after amplified by the high-speed power amplifier module. Overload protection module can cut off power supply when output overload in order to protect the power amplifier chip.This paper firstly introduces the background and significance of this topic, tidying the present situation about the technology of synchronous phasor measurement at home and abroad, the application as well as testing of PMU devices. Then according to the national related specification put forward the functions and the performance indicators of the PMU dynamic performance detector designed by this topic, and introduces the methods to realize related functions. Following describes the hardware design and software design of the detector in detail. Finally introduces the debugging process of hardware and software, finds and solves various problems, and completes the whole detector at last, and have a test to it, a detailed record of the result has been done. Test results show that the proposed various functions and indexes have been implemented and meet the requirements, the PMU dynamic performance detector has broad market prospects.