The Development Of PMU On-line Detection Device

With the development of phasor measurement technology,the Synchronized Phasor Measurement Unit(PMU),as the basic measurement device of Wide Area Measurement System(WAMS),has been widely used in the branches of interconnected power grids as the effect of comprehensively and effectively monitoring the dynamic operation of power systems.In recent years,the widespread usage of power electronic equipment has seriously interfered with the safe and stable operation of power systems.The increasingly complex and grid environment serves as severe challenges to the stable operation of PMU devices.Therefore,after connected to the network,PMU must be tested regularly in order to accurately reflect the operation of the power system.The subject of PMU on-line detection device has been based on GPS synchronization technology with the core of dual ARM architecture.And the frequency adaptive optimal filter algorithm is used to ensure the measurement accuracy under static conditions and the dynamic performance in transient state with the cooperation of the host computer platform,which can make sure that the PMU online device is an important test device and can be effectively analyzed online in real time without offline detection of the PMU for ensuring the effective operation of the PMU.Actually,the entire device hardware can be divided into two parts: data acquisition module and communication control module.Both modules use STM32F407ZGT6 as data interaction and control center.The data acquisition module converts the large signal of the power grid into a small signal through the sampling circuit,then sends it to the 16-bit high-speed,high-precision sampling chip ADS8568 for asynchronous sampling,and finally transmits the converted digital quantity to the communication control module through the high-speed SPI.For the communication control module,the received sampling data is processed by an algorithm to obtain voltage,current phasor and frequency,and transmitted to the liquid crystal display for real-time display.What's more,the data packet is packaged and matched by a high-precision GPS synchronous clock together with the electrical parameters.And after the standard uploaded to the host computer,the host computer analyzes and compares the received data with the data uploaded by the PMU and performs error check processing to realize online verification of the PMU.The thesis is a review from the theoretical analysis to the design of the program,then to the realization of the specific program.Firstly,on the basis of research background and significance of the PMU online detection device,the research content has been proposed.Secondly according to the research content,the functions and technical indicators of the device are obtained.Then the theoretical simulation,verification of the relevant principles and functional algorithms are carried out.Furthermore,the hardware design and software writing process of each part of the device are introduced.After that,the overall debugging process of the system is elaborated,and the overall function test is carried out by using Fluke 6100 A standard power source and RD-33 standard table.Moreover,the test shows that the performance indicators of the device have reached the expected design requirements.Finally,the insufficiency of the system design has been analyzed and summarized and the improvement measures also has been proposed.