无刷直流电机

无厘头

用RMxprt对无刷直流电机进行计算分析，计算清单中显示每相电枢电阻R=0.00681976欧姆，而电枢电流为Ia=186.332A(电机额定电压Un=600V,每相管压降DU=1.5V，线感应电动势E=546V，采用三相六状态导通方式)，而按计算公式Ia=(Un-2*DU-E)/2/R计算，Ia=3739.1345A，为什么会有这么大差距啊？在手算设计时我的电枢电流和绕组线规的选择也一直有问题，不知道哪里出了差错，希望能有人帮忙解答一下~下面是我RMxprt的计算清单
BRUSHLESS PERMANENT MAGNET DC MOTOR DESIGN

                      File: Setup1.res


     GENERAL DATA

Rated Output Power (kW):        100
Rated Voltage (V):        600
Number of Poles:        4
Given Rated Speed (rpm):        30000
Frictional Loss (W):        600
Windage Loss (W):        200
Rotor Position:        Inner
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):        1
One-Diode Voltage Drop (V):        0.5
Operating Temperature (C):        75
Maximum Current for CCC (A):        0
Minimum Current for CCC (A):        0


     STATOR DATA

Number of Stator Slots:        6
Outer Diameter of Stator (mm):          198
Inner Diameter of Stator (mm):          122

Type of Stator Slot:        4
Stator Slot       
            hs0 (mm):          4
            hs1 (mm):          0
            hs2 (mm):          10
            bs0 (mm):          3
            bs1 (mm):          37
            bs2 (mm):          46
            rs (mm):          0.5

Top Tooth Width (mm):          32.9386
Bottom Tooth Width (mm):          35.1444
Skew Width (Number of Slots)        0

Length of Stator Core (mm):          192.5
Stacking Factor of Stator Core:        0.95
Type of Steel:        D23_50
Designed Wedge Thickness (mm):          5
Slot Insulation Thickness (mm):          0.3
Layer Insulation Thickness (mm):          0.3
End Length Adjustment (mm):          70
Number of Parallel Branches:        1
Number of Conductors per Slot:        6
Type of Coils:        20
Average Coil Pitch:        1
Number of Wires per Conductor:        5
Wire Diameter (mm):          1.97
Wire Wrap Thickness (mm):          0.07
Slot Area (mm^2):        449.893
Net Slot Area (mm^2):        187.212
Limited Slot Fill Factor (%):        75
Stator Slot Fill Factor (%):        66.6881
Coil Half-Turn Length (mm):          399.135


     ROTOR DATA

Minimum Air Gap (mm):          2
Inner Diameter (mm):          55
Length of Rotor (mm):          192.5
Stacking Factor of Iron Core:        0.95
Type of Steel:        D23_50
Polar Arc Radius (mm):          59
Mechanical Pole Embrace:        0.8
Electrical Pole Embrace:        0.798323
Max. Thickness of Magnet (mm):          7.7
Width of Magnet (mm):          69.3035
Type of Magnet:        Material1
Type of Rotor:        1
Magnetic Shaft:        No


     PERMANENT MAGNET DATA

Residual Flux Density (Tesla):        0.95
Coercive Force (kA/m):        740
Maximum Energy Density (kJ/m^3):        175.75
Relative Recoil Permeability:        1.02163
Demagnetized Flux Density (Tesla):        5.79834e-005
Recoil Residual Flux Density (Tesla):        0.95
Recoil Coercive Force (kA/m):        740

     MATERIAL CONSUMPTION

Armature Copper Density (kg/m^3):          8900
Permanent Magnet Density (kg/m^3):          7800
Armature Core Steel Density (kg/m^3):          7820
Rotor Core Steel Density (kg/m^3):          7820

Armature Copper Weight (kg):          1.94897
Permanent Magnet Weight (kg):          3.20503
Armature Core Steel Weight (kg):          23.4555
Rotor Core Steel Weight (kg):          8.42586
Total Net Weight (kg):          37.0354

Armature Core Steel Consumption (kg):          45.2517
Rotor Core Steel Consumption (kg):          12.525


     STEADY STATE PARAMETERS

Stator Winding Factor:        0.866025
D-Axis Reactive Inductance Lad (H):        1.70504e-005
Q-Axis Reactive Inductance Laq (H):        1.70504e-005
D-Axis Inductance L1+Lad(H):        5.63978e-005
Q-Axis Inductance L1+Laq(H):        5.63978e-005
Armature Leakage Inductance L1 (H):        3.93474e-005
Zero-Sequence Inductance L0 (H):        1.41836e-005
Armature Phase Resistance R1 (ohm):        0.00681976
Armature Phase Resistance at 20C (ohm):        0.0056098
D-Axis Time Constant (s):        0.00250014
Q-Axis Time Constant (s):        0.00250014

Ideal Back-EMF Constant KE (Vs/rad):        0.163088
Start Torque Constant KT (Nm/A):        0.0591956
Rated Torque Constant KT (Nm/A):        0.172047


     NO-LOAD MAGNETIC DATA

Stator-Teeth Flux Density (Tesla):        1.36958
Stator-Yoke Flux Density (Tesla):        1.33885
Rotor-Yoke Flux Density (Tesla):        1.15716
Air-Gap Flux Density (Tesla):        0.670139
Magnet Flux Density (Tesla):        0.756625

Stator-Teeth By-Pass Factor:        0.0013785
Stator-Yoke By-Pass Factor:        5.19773e-005
Rotor-Yoke By-Pass Factor:        3.33974e-005

Stator-Teeth Ampere Turns (A.T):        15.0993
Stator-Yoke Ampere Turns (A.T):        31.0227
Rotor-Yoke Ampere Turns (A.T):        9.48486
Air-Gap Ampere Turns (A.T):        1104.27
Magnet Ampere Turns (A.T):        -1159.84

Armature Reactive Ampere Turns
  at Start Operation (A.T):        67857.2
Leakage-Flux Factor:        1
Correction Factor for Magnetic
  Circuit Length of Stator Yoke:        0.439046
Correction Factor for Magnetic
  Circuit Length of Rotor Yoke:        0.528494

No-Load Speed (rpm):        35319.7
Cogging Torque (N.m):        1.06336


     FULL-LOAD DATA

Average Input Current (A):        186.332
Root-Mean-Square Armature Current (A):        158.923
Armature Thermal Load (A^2/mm^3):        155.659
Specific Electric Loading (A/mm):        14.9273
Armature Current Density (A/mm^2):        10.4279
Frictional and Windage Loss (W):        800.893
Iron-Core Loss (W):        10113.3
Armature Copper Loss (W):        516.732
Transistor Loss (W):        367.216
Diode Loss (W):        14.1904
Total Loss (W):        11812.3
Output Power (W):        99986.8
Input Power (W):        111799
Efficiency (%):        89.4343

Rated Speed (rpm):        30022.3
Rated Torque (N.m):        31.8031

Locked-Rotor Torque (N.m):        2590.4
Locked-Rotor Current (A):        43763.2


     WINDING ARRANGEMENT


Angle per slot (elec. degrees):        120
Phase-A axis (elec. degrees):        60
First slot center (elec. degrees):        0



     TRANSIENT FEA INPUT DATA

For Armature Winding:
  Number of Turns:        6
  Parallel Branches:        1
  Terminal Resistance (ohm):        0.00681976
  End Leakage Inductance (H):        9.46128e-006
2D Equivalent Value:
  Equivalent Model Depth (mm):        192.5
  Equivalent Stator Stacking Factor:        0.95
  Equivalent Rotor Stacking Factor:        0.95
  Equivalent Br (Tesla):        0.95
  Equivalent Hc (kA/m):        740
Estimated Rotor Moment of Inertia (kg m^2):        0.0285794

无厘头

有人可以帮忙的吗？

沙隆巴斯

多年以来一直认为rm算的有点问题，换成speed会好很多。包括之前JMAG的解析模块算出来都效果不好。

无厘头

沙隆巴斯 发表于 2018-4-25 19:45
多年以来一直认为rm算的有点问题，换成speed会好很多。包括之前JMAG的解析模块算出来都效果不好。

speed是什么软件啊，不好意思，刚接触电机设计不久，对这些不太了解

samuelrzg22

无厘头 发表于 2018-4-27 22:35
speed是什么软件啊，不好意思，刚接触电机设计不久，对这些不太了解

你的空载转速为什么是3万多？

samuelrzg22

还有就是你的空载反电势电是怎么得到的？

无厘头

samuelrzg22 发表于 2018-5-4 16:18
你的空载转速为什么是3万多？

额定转速是30000，空载转速30000+算是正常的吧

无厘头

samuelrzg22 发表于 2018-5-4 16:19
还有就是你的空载反电势电是怎么得到的？

这个上面好像没有空载反电动势，需要自己计算吧，就我刚刚跟你说的公式

samuelrzg22

无厘头 发表于 2018-5-4 16:37
额定转速是30000，空载转速30000+算是正常的吧

我看错了，看成600了