Design Of Wind Turbine Blade Lightning Wire Break Detection System

If the wind turbine is struck by lightning during the normal operation of power generation,it will lead to the local failure of mechanical system or electrical system.In serious cases,it will cause serious accidents such as blade burst and fire,and lead to a long shutdown time,thus causing a large amount of loss of power generation.In addition,the wind turbine has high cost.If struck by lightning,especially valuable parts such as blades and generators,it will not only delay power generation due to maintenance and thus lose power generation,but also bring huge transportation and lifting costs to remove and replace damaged parts.The imperfect lightning protection system of wind turbine will cause fire in serious cases.In addition to ensuring the safe and stable operation of the wind turbine during the thunderstorm season,the design of the wind turbine lightning protection system also ensures the safety of the personnel who maintain the wind turbine during the thunderstorm season.Therefore,the lightning protection system design of large wind turbine plays an important role in the design of the whole wind turbine,which is worthy of further study and application.In this paper,a wind turbine blade lightning wire break line test system is proposed,which mainly consists of pulse signal generator,high frequency current sensor,signal pre-processing system,signal acquisition system and upper computer software.Pulse signal generator and high frequency current sensor installed in the leaf root part of the wind turbine blade,high frequency current sensor in the form of Rogovsky coil,blade lightning line is located in the center of the sensor,the output of the high frequency current sensor is connected to the signal pre-processing system,the signal pre-processing system includes integrated amplifiers and filters.After the signal pre-processing system access signal acquisition system,the signal acquisition system adopts the high-speed acquisition card,after the acquisition card enters the upper machine software power-out system,the signal processing and discrimination.Compared with the existing lightning-rod wire break test device and technical methods,with the obvious technical advantages of easy test and test ingress position,the test device is lightweight and compact,can be tested only by installing at the root of the leaf,compared with the conventional Ohm test system,no need to use artificial lifting device,and the test system's external wiring,At the same time,the test method can accurately locate the exact location of the lightning line break.This is a significant improvement over the previous Omacta.The pulse control signal of the test system and the excitation pulse control signal of the generator control signal are square wave test signal.The signal of the square wave test needs to have pulse rising motion edge and pulse falling motion edge with bandwidth less than 20 ns.The output amplitude is more than 5 VPP,the output frequency range is 1 KHz~500 KHz bandwidth range adjustable.acquisition card for high-speed signals with a bandwidth of not less than 500 M.The system can quickly collect and store a large amount of data in the complex testing process,at the same time,it can accurately and conveniently determine the location of each fault occurrence point,and the accuracy of the detection data is within 0.5 meters.