Calculating Load with Magnetometer for Synchronous Motor

AI Thread Summary
The discussion focuses on calculating the load of a synchronous motor using a magnetometer sensor, emphasizing that the load is proportional to the angle between the rotor poles and the stator's rotating magnetic field. The angle, which can be expressed as a phase difference, can be measured using a compass-like device mounted on the rotor. A formula for power is suggested as P = Pmax * sin(θ), where Pmax is a constant based on system specifics. While measuring the rotor angle with a magnetometer is theoretically possible, participants suggest that measuring voltage and current might be simpler for estimating load. The conversation also touches on the applicability of these concepts to synchronous servo motors and the potential use of an accumulator sensor for load detection.
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Looking for any insight on a formula that can be used to calculate the load using a magnetometer sensor for synchronous motor
 
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Synchronous motor load is proportional to the angle between the rotor poles and the rotating magnetic field in the stator. Angle can also be expressed as phase difference.

If you had a compass needle mounted on the outer perimeter of the rotor by at the pole, out would point in the direction of the rotor angle. So it it's the direction of that magnetic field, not the magnitude.
 
Many thanks anorlunda,
Is the increase in the load will affect the magnetic field ?
if it is possible can you help me to write the formula
 
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Where is your magnetometer mounted?
Can it measure direction?
 
If you can measure the rotor angle ##\theta##, the equation for power will then be ##P=P_{max}\sin\theta##.

Where ##P_{max}## is a constant dependent on the details of the grid and the load and the wiring and the voltages.
 
anorlunda said:
Where is your magnetometer mounted?
Can it measure direction?
yes, it can measure the direction
 
anorlunda said:
Synchronous motor load is proportional to the angle between the rotor poles and the rotating magnetic field in the stator. Angle can also be expressed as phase difference.

If you had a compass needle mounted on the outer perimeter of the rotor by at the pole, out would point in the direction of the rotor angle. So it it's the direction of that magnetic field, not the magnitude.
Hi @anorlunda, I just want to check if I have a synchronous servo motor is this will make any difference
 
It applies to all kinds of synchronous motors.

But there is a lot of engineering needed to measure that angle with a magnetometer. But in principle it is possible.
 
But why not measure voltage and current to estimate load. Those are much easier to deal with IMO.
 
  • #10
DaveE said:
But why not measure voltage and current to estimate load. Those are much easier to deal with IMO.
Because I want to use a magnetic field sensor to get the load, I'm unable to determine the voltage or current in this case.
 
  • #11
I want to ask about If I have accumulator sensor can It be used to detect or determine and calculate the load
 
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