I need to simulate a PMSG and I have found a commercial generator. According to the available information in datasheet, I can calculate the stator resistance, inertia, voltage constant, and flux linkage. However, I need to calculate the d- and q-axis inductance or at least the line to line inductance curve. Although it is possible to measure this curve in lab, I do not have access to the generator and I need to predict these values just from the information available in datasheet.
If you have all the information, you can calculate the d-q axis inductance of the generator, check the literature: Power system stability and control, the author : Kundur., hope this could help you, Best regards!
As long as my knowledge, the d-q model inductance does not depend on PMSG or not. It depends on the rotor type of generator. The salient pole generator can derived by two axis model and one axis model for other. If you have the hold information, I think you can obtain it. You can also read the textbook of Power System Analysis by J.J Granger and W.D Stevenson. In the Chapter SG, they illustrate it. Regards.
I presume the generator has a symmetrically wound three phase stator winding with the PM located on the rotor. In the case of a PMSM and unlike the traditional wound or squirrel cage rotor induction machine no induction takes place from stator to rotor as there is no need to induce rotor currents to create a rotating magnetic field on the rotor as the PM themselves are a source of flux or stored magnetic energy and may be considered a very high (infinite) resistance. Thus electromagnetic torque is created simply when stator current flows and the resultant magnetic field interacts with the PM Field on the rotor.
As such the stator d and q self-inductance only consist of leakage, as there is no mutual component Ls = L11 + LM = Ll + Lm + Lm = Ll + 2Lm. But as Lm = 0 for the PMSM we have L11 = Ll. This is why PMSM servo motors require much faster switching devices as they have much faster stator time constant due to lower stator self-inductance.
Thus if one had two machines one a conventional three phase squirrel cage induction machine and the other a PMSM machine and both have identical stator windings then the only difference in the d,q stator axis inductance will be Lm.
Thus for SCIM L11 = Li + Lm
for PMSM L11 = Li
Thus if you considered a similar rated SCIM then I would say that the leakage inductances will be very similar if not the same.
In the past we have modified a conventional SCIM to a PMSM and found this to be the only real difference in terms of the stator d,q axis inductances.
I am not sure if this will help but it is a practical engineering solution if you have access to the parameters of a similar rated SCIM.
G. Diana : Thank you very much for your answer. However, I am wondering if it is possible to calculate these parameters from the information available in datasheets without doing practical measurements. I am not so familiar with this concepts and I am sorry if my question is not so accurate.
Queval Loic: Would you please let me know how can I do that? What I need is the values of the d-q inductance when I just have the datasheet of the machine. I have no access to the machine itself and I cannot do any practical measurements.
Queval Loic: Please find attached a sample datasheet of a PMSG suitable for direct-drive appications. As I understand, I can calculate the voltage constant as the slope of the open-circuit voltage vs. the angular velocity. Using the open-circuit vs. the angular velocity, I can calculate the flux linkage multiplied the pole pairs as a curve for different values of the angular velocity. Hence I can also calculate the torque constant. However, I need the Ld and Lq for simulating the machine.
http://ginlong.com/download/200908/GL-PMG-12k_Horizontal_Specification_Sheet.pdf
After checking your datasheet, You can not estimate the inductances .... No way.
If you have data of phase resistance and short-circuit current, you can try to estimate Xd and Xq.
Dear Arash,
The data you have is for 10 kW machine. There are many 10 kW induction machines available from many manufacturers which have the parameters freely printed in the catalogue and as mentioned above why would they differ!
Alternatively just write to the manufacturer in China and ask them?
Dear Diana,
Actually, I asked them and they gave me the values; however, it seems that manufacturers normally are not providing them as part of their datasheet and I am looking for a systematic algorithm to extract them from the information available in the datasheet.
By the way, it seems that there is no such a big number of manufacturers which are producing the PMSGs appropriate for the small-sized direct-drive applications. I searched and most of manufacturers were Chinese (no surprising :)). Would you please let me know if you know any specific manufacturer?
Regards
Dahaman Ishak, It seems so. I think I need some practical measurements.
Oladapo Ogidi, Thank you for your help; however, all these companies are either the manufacturers or solution providers of the integrated wind turbines. They are not the PMSG manufacturers.
If you have no access to the machine for measurements or a lamination drawing depicting the magnetic anisotropy of the magnetic circuit, there will be no chance to get these parameters exactly. It depends very much on the construction of the rotor. If the magnets are surface mounted xd equals xq. If the magnets are embedded you often find xd
how to calculate dq-axis inductance and resistance in induction motor?
Muhammad Rizani Rusli the dq inductances are equal in a symmetrical induction motor.
Dear Muhammad Rizani Rusli
Would you please clarify more your statement?
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