Motor electrical angle waveform acquisition

studyking

Motor electrical angle waveform acquisition [Copy link]

Hello, teachers. I am using DSP2812 to control a brushless DC motor. I want to collect the electrical angle waveform shown in the figure below. This waveform should be collected with an oscilloscope.

But I can't figure out how to collect it? ?

And how to get the motor speed waveform and torque pulsation waveform?

Please give me some advice, thank you!!

maychang

If you want to measure the electrical angle, you should probably measure the magnetic flux density. If you want to measure the speed, you can differentiate the electrical angle. If you want to measure the average speed over a period of time, you can count the electrical angle cycles. Torque measurement is more complicated.

studyking

maychang posted on 2018-5-9 10:39 Electrical angle, it is estimated that it should measure magnetic flux density. To measure the rotation speed, just differentiate the electrical angle. If it is to measure the average rotation speed over a period of time, you can...

Teacher, hello, I don’t quite understand. If measuring electrical angle is to measure magnetic flux density, there is no way to use an oscilloscope to check this? I don’t know how to use an oscilloscope to display this waveform.

maychang

studyking posted on 2018-5-9 13:57 Hi, teacher. I don't quite understand. If the electrical angle is to measure the magnetic flux density, there is no way to use an oscilloscope to measure it, right? I don't know how to use an oscilloscope...

The magnetic flux density can be measured with a Hall element, and the output of the Hall element can be measured with an oscilloscope.

studyking

maychang posted on 2018-5-9 14:49 Hall elements can be used to measure magnetic flux density, and the output of Hall elements can be measured with an oscilloscope.

That's embarrassing, there are not enough devices. Thank you, teacher!

sanhuasr

Electrical or mechanical?

studyking

sanhuasr posted on 2018-6-6 09:23 Electrical angle or mechanical angle?

Electrical angle, mechanical angle measurement has no practical value, right?

魔人布欧01

studyking posted on 2018-6-20 09:24 Electrical angle, mechanical angle measurement has no practical value, right?

Electrical angle is equal to mechanical angle multiplied by the number of pole pairs of the motor

gangqun

Is it the electrical angle that you control yourself? Or is it the electrical angle of the actual rotor position? If it is controlled, you can use a DAC 8-bit output and connect it to an oscilloscope

zst588

Thank you for sharing!

nian1206

Give a thumbs up, the poster is really a good person for sharing his information so completely.