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BLDC/Inverter current

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treez

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Hello,
When a 550W , BLDC is being supplied by a 3 phase voltage source inverter, and it is spinning at 8000rpm with 34V across it, and the inverter is switching at 400Hz with 400us dead time, what does the current waveform look like flowing into the inverter?
(assuming the DC link is 34V, and the inverter is switching at its maximum duty cycle)

Is it a train of trapezoids, separated by the dead time gap, and the peak current of each trapezoid being given by what?, given that the inductance of each winding is 56uH.

none of the web articles actually show the current waveform into the inverter..
https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.168.3186&rep=rep1&type=pdf
 

A question arises. An inverter implies AC. But your BLDC motor is DC. I guess the AC is rectified, to become DC?

And if 3-phase is rectified, it becomes smooth DC (more or less)?
 
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I see the wave forms depicted on pages 1637 and 1638 of your provided linked doc are the ones you are looking for
 
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thanks but none of those waveforms show the current flowing from the dc link capacitor to the inverter.
All of those waveforms bar one are AC....and its DC pulses which flow to the inverter from the dc link capacitor....the one waveform that's dc is triangular and is obviously not the current from the dc link capacitor.

Are the current pulses to the inverter from the dc link capacitor flat topped or trapezoidal?
 

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