TI C2000 Delfino - SVGenDQ block outputting negative duty ratios
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Hi there, I've set up a simple test for the PID, IPark and SVGenDQ blocks for a three phase motor control application as shown below. I'm simply setting a reference D and Q axis current, defined by the variables i_d_ref_IQ and i_q_ref_IQ respectively. I'm then setting my own value for the "actual" D and Q axis currents instead of using measured values, since my aim is to just observe the behaviour of the PID, IPark and SVGenDQ blocks. The "actual" currents are defined by the variables i_d_ref_mimicked_IQ and i_q_ref_mimicked_IQ. Note that the IQ suffix indicates a fixed-point data type.
Image A: Setup of the SVGenDQ block. It can be seen that negative duty cycles are obtained at the outputs of the SVGenDQ block even though the documentation claims these outputs should be duty ratios
The PID and IPark blocks seem to be working correctly, but what is of interest is that the SVGenDQ block is outputting negative numbers as seen in the next image.
Image B: Documentation for the SVGenDQ block implies that we should be expecting duty ratios at the outputs, with values between 0 and 1.
Is there an explanation for why the SVGenDQ block is outputting values outside the [0, 1] range as shwon in Image A, particularly negative values?
Please let me know if I'm misinterpreting anything.