I want to know whether there is major differences in simulation of BLDC with Trapezoidal commutation and sinusoidal commutation. Seems like there is problem in the Hall sensors detecting the electrical angle sequences with sinusoidal commutation. Can anyone suggest me the ways for perfect commutation in BLDC motor with sinusoidal back emf for positive and negative switching states?
There are many questions in your post, it is not very easy to grasp what you are really interested in. I will try to answer some of them.
A BLDC motor is just a Permanent Magnet Synchronous Motor (PMSM) with trapezoidal back-emf. Often a BLDC motor is fitted with Hall sensors so as to easily implement a so-called six-step control scheme. On the other hand, a sinusoidal PMSM is not fitted with Hall sensors; if you want to implement a control scheme with position feedback, an encoder is needed. This is the case when high-precision positionning is required (as in machine-tools); on the other hand, if you are interested only in velocity control (as in many industrial machines, pumps, fans, etc.), you can avoid the costly and fragile (for industrial standards) position sensor, and use a "sensorless" control scheme. Sensorless schemes are more complicated, since they must somewhow extract the rotor position information from the measured electric signals; tthe schemes for trapezoidal and sinusoidal motors are usually quite different (and so are the expected levels of performance).
As far as simulation is concerned, there is no difference, the model equations are nearly the same (in fact you could without more diffculty simulate a PMSM with an any prescribed back-emf).
Anyway, your questions are too vast to be answered in a short message. I suggest you read one of the many books on the subject, for instance "Modeling and High Performance Control of Electric Machines" by J. Chiasson.
https://books.google.fr/books?id=cq6RPPsOyt8C&redir_esc=y
Hello,
there is no 'problem' with the hall sensors in sinusoidal control - other than that the hall sensor information is simply not sufficient.
Sinusoidal control requires a higher resolution information about the rotor position than the hall sensors can deliver. Thus sinusoidal control either uses position sensors like sin/cos magnetical or incremental position sensors. Or position sensing via current sensing is applied.
Regards
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