风力发电机组振动分析技术

第三部分振动分析技术012345672002.01.172002.01.182002.02.072002.03.182002.03.282002.04.092002.04.262002.05.232002.06.282002.07.072002.07.092002.07.152002.07.302002.08.152002.08.222002.08.258H8A9V振动趋势分析的重要性ISO2372(10Hz--1000Hz)振动标准现场设备的周期性振动X（t），不论其振动波形有多复杂，都可以用傅立叶级数表示为许多频率成谐波关系的简谐振动组成：频谱分析技术从时域波形到频谱图时域波形正弦波FFT=FastFourierTransfer快速傅立叶变换振动频谱amplitude-frequencyscale1X频率(水平)1X频率(水平)1X频率(铅垂)1X频率(铅垂)轴向很小轴向很小转子不平衡转子不平衡正确对中平行不对中角度不对中平行和角度不对中轴系不对中timevel,frequency1X3X2X轴系不对中frequency1X3X2X4X5X6X0.5Xvelocity机械松动正常齿轮磨损齿轮齿轮偏心齿轮不对中齿轮故障“时域”图?Y-轴单位:振幅X-轴单位:时间(秒或毫秒)“时域”图?滑动轴承或轴承座松动可能出现的频谱滑动轴承在线频谱分析frequencymm/srms0.45X2X1X油膜涡动引起的半倍频应用滑动轴承的监测——频谱分析frequencymm/srms0.45X2X1X油膜涡动引起的半倍频滑动轴承的监测——轴心轨迹SHAFTSENSORSENSOR应用滚动轴承滚动体BSF=D/2d（1-d²cos²/D²）外环BPFO=Zn/2（1-dcos/D）内环BPFI=Zn/2（1+dcos/D）保持架FTF=n/2（1-dcos/D）d滚动体直径D节园直径接触角Z滚动体数n轴频滚动轴承的特征频率020406080100202xnn0100200300400500600700800900100000.20.40.6不平衡轴承故障Hz滚动轴承的特点——瞬态冲击t0.000010.000020.1600.0050.010.0150.020.0250.030.035202轴承损伤不平衡Resonance00.0050.010.0150.020.0250.030.035202瞬态信号湮没t0.000010.000020.1600.0050.010.0150.020.0250.030.035202频谱分析的改进——包络UnbalancePeaksaroundtheresonansfrequency带通滤波020406080100202xnn0500011041.510421042.510431043.5104410400.05Hz0.100.1带通滤波0.1整流001.包络峰值检测t0.000010.000020.1600.0050.010.0150.020.0250.030.035202Bearingdamage00.1Bearingdamage普通的FFT频谱——纷杂的信号包络谱图——仍不理想包络滤波设置,HP2000Hz，线性频谱功率谱我们竞争对手的“加速度包络”图二：包络频谱（低速轴承）我们竞争对手的“加速度包络”EVAM智能分析评估60504030201001000Hz振动总量VelAcc冲击CrestKurtSkew摩擦NL1NL2NL3NL4征兆齿轮啮合不平衡不对中EVAM®EvaluatedVibrationAnalysisMethod传统的振动分析方法=FFT振动总量的评判标准——ISO108163-1000Hzmm/sRMS00.511.522.53050100150200250hardwaresoftwareevaluationEVAM®时域时域分析状态参数冲击信号CRESTKURTSKEW峰值因子峭度歪度摩擦周期或非周期NL1NL2NL3NL4旋转力产生的振动加速度ACC加速度的均方根值速度VEL速度的均方根值时域计算冲击参数单一瞬时信号CREST=4.210KURT=-1.244SKEW=+0.062重复信号CREST=4.046KURT=-0.227SKEW=+0.319重复信号,反向CREST=4.046KURT=-0.227SKEW=-0.31对于正弦波:CREST=1.414KURT=-1.500SKEW=0.000ABKURTSKEWCRESTvpeakv-3()vt-v3s1nSt~()vt-v4s1nSt~RMS趋势和报警极限•齿轮•其他冲击ACCVEL•不平衡•不对中•松动•磨损•动静部件间摩擦•CRESTKURTSKEWNL1-4征兆评估CONDNo.35-60红5std21-34黄3-5std0-20绿upto3std21-34黄3-5std35-60红5std统计mm/sTime中值.TimeACCm/s2TimeVEL,mm/sCriteriacalculationCriteriacalculation状态参数评估6050403020100旋转力速度加速度Shock幅值因子峭度歪度摩擦NL1NL2NL3NL4频域征兆清单理论征兆EVAM自动搜索0.000.020.040.060.080.100.12020406080100120140160180200Hzmm/secuncertaintyduetoRPMfluctuationin%,+uncertaintyofsymptom,slippageetc.EVAM自动匹配征兆匹配征兆征兆设置征兆驱动轴征兆0,04mm/s0,99mm/sTime2X转频,mm/sCriteriacalculation手动报警设置驱动轴趋势驱动轴征兆齿轮箱3:RDSHAFTBEARINGSKFNJG2332VH(BPFO,BPFI,BPFIM,BSF,BSFM)GEARWHEELZ63(GM,GMMOD)部件1:STSHAFTBEARINGSKF32320GEARWHEELZ132:NDSHAFTBEARINGSKFNCF2944VGEARWHEELZ36EVAM的征兆分析软件设置征兆匹配征兆赋值200BroadbandRMS-value=SymptomRMS-value=776543212vvvvvvvnvnnSymptomsasVALUEorCONDv4v2v3v5v6v7v1mm/sEVAM的结果60504030201001000Hz振动总量VelAcc冲击CrestKurtSkew摩擦NL1NL2NL3NL4征兆齿轮啮合不平衡不对中Atyourservice...@BMAAdvancedInstrumentLtd.2006-01-M02