Maxwell与Workbench联合仿真电磁噪声 仿真结果与实验数据偏差太大

逗叉派来的谜鹿

用ANSYS EM 仿真电磁噪声
8极12槽无刷直流电机   仿真结果声压级最高有100+    但是装有电机的轴流风机 噪声测试 SPL也就50+   按常理电机噪声40dB左右
求问各路大神 帮我提点一下关键问题点 非常非常感谢bq2_11
新手一个 可能有些地方说得很不专业 敬请谅解

下面附一些 仿真数据

电机是由rmxprt 参照实物、风机规格和用户手册生成的

电机信息
  GENERAL DATA

Rated Output Power (kW):        0.096
Rated Voltage (V):        48
Number of Poles:        8
Given Rated Speed (rpm):        11500
Frictional Loss (W):        12.3214
Windage Loss (W):        5.41264
Rotor Position:        Outer
Type of Load:        Constant Power
Type of Circuit:        Y3
Lead Angle of Trigger in Elec. Degrees:        0
Trigger Pulse Width in Elec. Degrees:        120
One-Transistor Voltage Drop (V):        2
One-Diode Voltage Drop (V):        2
Operating Temperature (C):        70
Maximum Current for CCC (A):        0
Minimum Current for CCC (A):        0


     STATOR DATA

Number of Stator Slots:        12
Outer Diameter of Stator (mm):          50
Inner Diameter of Stator (mm):          18

Type of Stator Slot:        3
Stator Slot       
            hs0 (mm):          1
            hs1 (mm):          1.35843
            hs2 (mm):          6.25655
            bs0 (mm):          2
            bs1 (mm):          6.70575
            bs2 (mm):          3.35287
            rs (mm):          1

Top Tooth Width (mm):          5.23253
Bottom Tooth Width (mm):          5.23253
Skew Width (Number of Slots)        0

Length of Stator Core (mm):          13
Stacking Factor of Stator Core:        0.95
Type of Steel:        DW540_50
Designed Wedge Thickness (mm):          1
Slot Insulation Thickness (mm):          0.3
Layer Insulation Thickness (mm):          0.3
End Length Adjustment (mm):          0
Number of Parallel Branches:        1
Number of Conductors per Slot:        60
Type of Coils:        21
Average Coil Pitch:        2
Number of Wires per Conductor:        1
Wire Diameter (mm):          0.31
Wire Wrap Thickness (mm):          0.06
Slot Area (mm^2):        42.3029
Net Slot Area (mm^2):        26.2987
Limited Slot Fill Factor (%):        75
Stator Slot Fill Factor (%):        31.2334
Coil Half-Turn Length (mm):          43.5042


     ROTOR DATA

Minimum Air Gap (mm):          1
Outer Diameter (mm):          60
Length of Rotor (mm):          24
Stacking Factor of Iron Core:        0.95
Type of Steel:        DW540_50
Polar Arc Radius (mm):          26
Mechanical Pole Embrace:        0.7
Electrical Pole Embrace:        0.693968
Max. Thickness of Magnet (mm):          3
Width of Magnet (mm):          14.1149
Type of Magnet:        NdFe30
Type of Rotor:        1
Magnetic Shaft:        No


     PERMANENT MAGNET DATA

Residual Flux Density (Tesla):        1.1
Coercive Force (kA/m):        838
Maximum Energy Density (kJ/m^3):        230.45
Relative Recoil Permeability:        1.0446
Demagnetized Flux Density (Tesla):        0.3746
Recoil Residual Flux Density (Tesla):        1.1
Recoil Coercive Force (kA/m):        838

     MATERIAL CONSUMPTION

Armature Copper Density (kg/m^3):          8900
Permanent Magnet Density (kg/m^3):          7550
Armature Core Steel Density (kg/m^3):          7750
Rotor Core Steel Density (kg/m^3):          7750

Armature Copper Weight (kg):          0.021041
Permanent Magnet Weight (kg):          0.0657491
Armature Core Steel Weight (kg):          0.114988
Rotor Core Steel Weight (kg):          0.032752
Total Net Weight (kg):          0.23453

Armature Core Steel Consumption (kg):          0.211159
Rotor Core Steel Consumption (kg):          0.31149


     STEADY STATE PARAMETERS

Stator Winding Factor:        0.866025
D-Axis Reactive Inductance Lad (H):        0.000179826
Q-Axis Reactive Inductance Laq (H):        0.000179826
D-Axis Inductance L1+Lad(H):        0.000587461
Q-Axis Inductance L1+Laq(H):        0.000587461
Armature Leakage Inductance L1 (H):        0.000407635
Zero-Sequence Inductance L0 (H):        0.000170671
Armature Phase Resistance R1 (ohm):        2.95343
Armature Phase Resistance at 20C (ohm):        2.46926
D-Axis Time Constant (s):        6.08873e-005
Q-Axis Time Constant (s):        6.08873e-005

Ideal Back-EMF Constant KE (Vs/rad):        0.0863343
Start Torque Constant KT (Nm/A):        0.0860784
Rated Torque Constant KT (Nm/A):        0.0869897


     NO-LOAD MAGNETIC DATA

Stator-Teeth Flux Density (Tesla):        1.83159
Stator-Yoke Flux Density (Tesla):        0.773204
Rotor-Yoke Flux Density (Tesla):        2.81377
Air-Gap Flux Density (Tesla):        0.627759
Magnet Flux Density (Tesla):        0.382053

Stator-Teeth By-Pass Factor:        0.00828268
Stator-Yoke By-Pass Factor:        8.58081e-006
Rotor-Yoke By-Pass Factor:        0.133002

Stator-Teeth Ampere Turns (A.T):        90.124
Stator-Yoke Ampere Turns (A.T):        0.402307
Rotor-Yoke Ampere Turns (A.T):        1031.26
Air-Gap Ampere Turns (A.T):        519.32
Magnet Ampere Turns (A.T):        -1640.84

Armature Reactive Ampere Turns
  at Start Operation (A.T):        117.195
Leakage-Flux Factor:        1
Correction Factor for Magnetic
  Circuit Length of Stator Yoke:        0.826864
Correction Factor for Magnetic
  Circuit Length of Rotor Yoke:        0.350737

No-Load Speed (rpm):        4789.71
Cogging Torque (N.m):        0.0225528


     FULL-LOAD DATA

Note:
This motor cannot offer the given rated output power.
The following results are of the maximum output.

Average Input Current (A):        3.63779
Root-Mean-Square Armature Current (A):        2.97273
Armature Thermal Load (A^2/mm^3):        536.674
Specific Electric Loading (A/mm):        13.626
Armature Current Density (A/mm^2):        39.3861
Frictional and Windage Loss (W):        2.55459
Iron-Core Loss (W):        4.16376
Armature Copper Loss (W):        78.2996
Transistor Loss (W):        14.3878
Diode Loss (W):        0.164198
Total Loss (W):        99.57
Output Power (W):        75.0439
Input Power (W):        174.614
Efficiency (%):        42.977

Rated Speed (rpm):        2341.64
Rated Torque (N.m):        0.306032

Locked-Rotor Torque (N.m):        0.630618
Locked-Rotor Current (A):        7.44494


     WINDING ARRANGEMENT

The 3-phase, 2-layer winding can be arranged in 3 slots as below:

ABC


Angle per slot (elec. degrees):        120
Phase-A axis (elec. degrees):        120
First slot center (elec. degrees):        0



     TRANSIENT FEA INPUT DATA

For Armature Winding:
  Number of Turns:        120
  Parallel Branches:        1
  Terminal Resistance (ohm):        2.95343
  End Leakage Inductance (H):        0.000103903
2D Equivalent Value:
  Equivalent Model Depth (mm):        13
  Equivalent Stator Stacking Factor:        0.95
  Equivalent Rotor Stacking Factor:        1.75385
  Equivalent Br (Tesla):        2.03077
  Equivalent Hc (kA/m):        838
Estimated Rotor Moment of Inertia (kg m^2):        0.000235242

逗叉派来的谜鹿

仿真数据图C:\Users\F2A85\Desktop\222

254339861

Frictional Loss (W):        12.3214
Windage Loss (W):        5.41264
这数据有问题，先调整这两个参数，具体去看计算公式，不是随便填的。
噪声测试是带风叶空载测试吗？
请上测试噪声频谱图和仿真的频谱图

逗叉派来的谜鹿

254339861 发表于 2016-10-14 13:20
Frictional Loss (W):        12.3214
Windage Loss (W):        5.41264
这数据有问题，先调整这两个参 ...

设置的是12和5  然后资料生成 显示了这两个数据

逗叉派来的谜鹿

254339861 发表于 2016-10-14 13:20
Frictional Loss (W):        12.3214
Windage Loss (W):        5.41264
这数据有问题，先调整这两个参 ...

嗯 噪声测试是带风页空载时的噪声
风机单体自由状态入风口1米处噪声

254339861

从目前这些信息，请先把电磁模型调整和你测试时一样的。

254339861

我记得我很你说过，外转子电机的径向力是加在转子上面，定子振动主要通过轴承传递到外壳上，由于轴承具有弹性和一定的阻尼作用，传到外壳的高频振动会明显衰减。而转子一般直接连
接到电机外壳上，相比于定子振动，转子振动更容易引起外壳的振动和噪声。

逗叉派来的谜鹿

254339861 发表于 2016-10-17 12:55
我记得我很你说过，外转子电机的径向力是加在转子上面，定子振动主要通过轴承传递到外壳上，由于轴承具有弹 ...

可是我看实物，转子是连接风扇，定子连接了外壳……这样不就是定子更容易产生振动么？

flashchen

你实测的是dB A计权，而你计算结果是什么计权方式呀，这个你考虑考虑，我也是初学，进来学习讨论的。

flashchen

你实测的是dB A计权，而你计算结果是什么计权方式呀，这个你考虑考虑，我也是初学，进来学习讨论的。

夏tianxian

254339861 发表于 2016-10-17 12:55
我记得我很你说过，外转子电机的径向力是加在转子上面，定子振动主要通过轴承传递到外壳上，由于轴承具有弹 ...

你好，请问一下，workbench结构场如何看加速度的频域波形？谢谢！！