Stationary and Rotary Frames
Stationary and Rotary Frames
(OP)
Hi,
I have been searching for an explanation for some time online and in books about this, but none offered a clear explanation. Maybe someone here can help me. What does a stationary or a rotary frame mean when applied to Park and Clarke Transformations, please?
Thanks
I have been searching for an explanation for some time online and in books about this, but none offered a clear explanation. Maybe someone here can help me. What does a stationary or a rotary frame mean when applied to Park and Clarke Transformations, please?
Thanks





RE: Stationary and Rotary Frames
I like to think of the rotor of a machine when I think of these representations. If I'm observing the rotor from outside, I see the αβγ representation. If I'm sitting on the rotor and spinning with it, what appeared to be rotating phasors are now stationary vectors from my point of view, and I see the dq0 representation.
xnuke
"Live and act within the limit of your knowledge and keep expanding it to the limit of your life." Ayn Rand, Atlas Shrugged.
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: Stationary and Rotary Frames
So if I understood correctly in the case of the Clarke Transformation when it is stated that the transformation converts time domain signals from a stationary 3-phase phase coordinate system (ABC) to a stationary 2-phase coordinate system (αβγ), what is meant is that the frame (ABC) is stationary while the voltages (or currents) Va, Vb, Vc are rotating and the frame (αβγ) is also stationary while voltages (or currents) Vα, Vβγ, Vγ are rotating.
Again, if I understood correctly for the Park Transformation, it converts time domain signals from a stationary phase coordinate system (ABC) to a rotating coordinate system (dq0), where the frame (ABC) is stationary while the voltages (or currents) Va, Vb, Vc are rotating and the frame (dq0) is rotating while voltages (or currents) Vd, Vq, V0 are stationary.
So this is what makes the 3-phase voltages (or currents) after the (dq0) transformation appear as a constant (like a DC value) representing the magnitude?
RE: Stationary and Rotary Frames
xnuke
"Live and act within the limit of your knowledge and keep expanding it to the limit of your life." Ayn Rand, Atlas Shrugged.
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: Stationary and Rotary Frames
Thanks for the great help, xnuke, I really appreciate it.