故障频率Figure 10有关风电设备故障数据分析在瑞典，风电设备故障数据由Swedpower AB公司收集，每年都会发布报告报告内容是瑞 典境内风力发电机的性能，包括不同部件故障的停机时间下面的故障和停机数据是在2000-2004年内收集的，期间安装了越来越多的风力发电设备显示在2000-2004年内，故障百分比大多数故障与电气故障、传感器、叶片变桨Figure 10: Distribution of number of failures for Swedish ind power plants between 2000-2004 Source: Felanalys^ Daktb^se Swedpower AB 2005 [12]停机Figure 11显示在2000-2004年内，部件故障停机百分比最严重的故障部件是增速箱，其次 是 控 制 系 统 和 电 气 系 统 这Distribution of Downtime [%]Entire unit 17Drive train 2,4Figure 11: Percentage of downtime per component in Sweden between 2000-2004Source: Driftuppfoljning av Vindkraftverk Arsrapport 2000-2004 [9]意味着增速箱比其它部件故障时间都长。
增速箱故障Table 7中，故障最多的部件是轴承和其它不明部件导致故障的主要原因是：磨损Table 7: Type of gearbox failureType of reported failure codeComponentNumber of failures [n]Average downtime [h] (min-max)Number of failures, Cause: B1 [n]Average downtime, Cause: B1 [h]1-1Bearings41562 (15-2067)36601I-2Gearwheefs3272 (57-383)2379I-3Shaft0000J-4Sealing852 (2-218)430I-5Oil system1326 (1-63)536l-otherNot specified44230 (9-1248)19299总结一台风力发电设备每年故障率0.402起，每起故障需要维修的平均时间是170小时故障数量 最多的是：电气系统、传感器、叶片/变桨；停机数量最多的是：增速箱、控制系统、电气 系统；每起故障停机时间最长：驱动链、偏航系统、增速箱；引起增速箱故障的原因主要是磨损。
Table 8: SmniimTy of (hidings fon SwedenFindingsSwedenAverage number of failures0.402 times a yearAverage downtime52 hours per year; 170 hours per faihuMost number of failuresL Electrical system2, Sensors3. Blades,PitchMost amount of downtime1. Gears2. Control system3. Electrical systemLongest downtime per failureL Drive train2. Yaw system3. GearsImportant findings from the failures statistics1. Turbines below 1MW show simik small increase for the first three vc years it decreases.2. Turbines above 1M\V show an iiic operational years.Important findings concerning gearsL The amount of failures has tlecrea?2. The downtime for gearbox failurei3. The majority of the gearbox failur4. No link between brand of turbine < can be proved since lhe amount of types of turbines stand olii compai。