摘要
Abstract
In order to solve the problem of lightning protection system failure caused by faults such as breakage and poor contact of wind turbine blade lightning protection downleads,and to overcome the shortcomings of traditional resistance measurement methods that require shutdown and disassembly and low efficiency,a portable rapid detection system based on Time Domain Reflectometry(TDR)technology was designed and developed.The system injects high-frequency pulse signals into the lightning conductor,determines and locates faults by analyzing the characteristics of reflected waves;the hardware integrates a pulse generation module(pulse width 100～200 ns,amplitude adjustable),a high-speed acquisition module(50 MHz ADC),a processing unit(FPGA+microprocessor)and a human-machine interface.The fault distance is calculated by using the pulse propagation speed and reflection time difference in the conductor,and the fault type(open circuit,short circuit)is determined through the reflection coefficient.Through actual blade testing in the laboratory and wind farm,the system's positioning error for open and short circuit faults on 20～200 m conductors is less than 5%(the laboratory standard deviation is less than 2%),and the relative error for actual blade detection on site is less than 3%.In addition,the detection accuracy in a strong interference environment exceeds 90%,and the positioning error is controlled within±2%.The average time for a single detection process(including wiring,measurement,and analysis)is less than 5 minutes.The results show that the time domain reflection technology detection system realizes non-contact,rapid and accurate location and type judgment of lightning protection downlead faults of wind turbine blades,and can improve the efficiency and safety of wind power operation and maintenance.关键词
风机叶片/防雷接地系统/故障检测/时域反射技术/故障定位/脉冲反射/便携式检测系统/风电场维护Key words
wind turbine blade/lightning protection grounding system/fault detection/time domain reflection technology/fault location/pulse reflection/portable diagnostic system/wind farm maintenance分类
建筑与水利
