版主，各位请教 电机功角的问题

shenseng123

各位，
如题
在ansoft软件中，这个功角δ到底是定义为合成电流I与Q轴的 夹角，还是I与D轴的夹角？？



谢谢

focus2009

Analysis Approach for Line-Start PM Synchronous Motors
Synchronous motors use a three-phase sinusoidal voltage source to induce a rotating magnetic field in the stator. Applying this three-phase sinusoidal voltage source to the stator winding of a synchro­nous motor yields the rotational magnetic field in the air gap. The permanent magnet poles mounted on the rotor try to align in this rotating field, producing a synchronous torque on the rotor. Upon starting, the damping winding on the rotor generates the asynchronous starting torque, creat­ing a self-starting feature.

The phasor diagram for the line-start permanent-magnet synchronous motor (LSSM) in the fre­quency domain is shown in Figure 6.



In Figure 6, R1, Xd, and Xq are armature resistance, d-axis synchronous reactance, and q-axis syn­chronous reactance, respectively. Xd is the sum of leakage reactance, X1 and d-axis armature reac­tance Xad, and Xq is the sum of X1 and q-axis armature reactance Xaq:





For a given torque angle , the angle that E0 lags U, we have the following:





Solving for Id and Iq yields:





The angle that I legs E0 is:



The power factor angle (or torque angle) that I legs U, is:



The input power (electric power) can now be computed from voltage and current as:



The output power (mechanical power) is:



where Pfw, PCu, and PFe are frictional and wind loss, armature copper loss, and iron-core loss, respectively.

The output mechanical power (torque) T2 is:



where  is the synchronous speed in rad/s.

The efficiency is computed by:



The motor is started the same way as for an induction motor, by using a squirrel-cage-type winding -- called a damper winding in this case -- that is mounted on the rotor, producing the starting torque.

shenseng123

focus2009 发表于 2013-12-18 08:28
Analysis Approach for Line-Start PM Synchronous Motors
Synchronous motors use a three-phase sinusoi ...

可能本人没将问题描述清楚
我有疑问的地方是：

比如在ABC轴，
ia=im*cos（θ+δ）
ib=im*cos（θ+δ-120）
ic=im*cos（θ+δ+120）

计算一个简单的例子，如下：
当t=0，δ=0
按此作派克变换
得到： id=im，iq=0

看了很多文章
基本上对id，iq定义为
id=im*sinδ
iq=im*cosδ
按此计算
得到id=0，iq=im
这时δ定义为im与Q轴的夹角

这个结论与上面的派克变换出来的结果刚好相反
δ换一个数值，结果也是与派克变换出来的结果相反

δ只有定义为im与D轴的夹角才与派克变换相符
（另，试了多个派克变换形式，结果一致，所以不是派克变换的问题）

所以，这个δ到底定义为哪个夹角？？Q轴？D轴？？

请各位指点。

shenseng123

不好意思

疑问是：   控制角δ到底是指哪个夹角？？

missking

看看永磁同步电机向量图就明白了

realchen365

定子电流向量与转子磁场的夹角。转子磁场一般是径向永磁体充磁方向，旋转的永磁体坐标D轴。

hhs78

我也同问这个问题

panyuji

是内电势E与外电压U之间的夹角.

一只会飞的猪

shenseng123 发表于 2013-12-19 13:42
可能本人没将问题描述清楚
我有疑问的地方是：

我感觉你电流表达式中的相位角不是功角而应该是内功率因数角才对

Xander_zHR8h

以下是我对问题的解答