Do we add Vd term and decoupling term (Id*wL) directly to the output of PI controller or scale down to certain value?
Please refer the attached diagram
Dear Sagar, have a look at my paper, it answers your question.
http://www.ijrer.org/ijrer/index.php/ijrer/article/view/2426
Hi Sagar,
the states in the dq-rotating reference frame, also referred to as synchronous reference frame, are coupled. Which means the states in d- and q-axis are not independent (coupled). For this reason a decoupling technique is needed. Referring to currents in dq-axis, id*w*L is summed at the output of the controller (e.g. a PI) in q-axis, while iq*w*L is subtracted at the output of the controller in d-axis.
Hi Sagar,
as a extension to Federico explanation, a really good analysis of two decoupling techniques (the one that you mention and an alternative one) can be found in the classical paper:
L. Harnefors and H. P. Nee "Model-Based Current Control of AC Machines Using the Internal Model Control Method" IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VOL. 34, NO. 1, JANUARY/FEBRUARY 1998
@ashraf :I went through you paper which includes two control loop current and voltage control loop. How ever i am implementing only current loop in my case.
At the summation point I have three terms (PI controller o/p -Iq*wL+Vd) where the range of pi controller and -iq*wL is very less as compared to Vd. My question is how to add quantities which are very different in magnitude.Do I need to introduce gain to scale them down? I am using simulink platform for implementation.
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