current we are working in a project assigned for monitoring submersible pump. the method chosen is electrical motor current signature. my question is there any ready sensor for acquiring electrical current signal available in the market or we should design and construct our sensor ?
Dear Prof Salem. A. Al-Hashmi
The current sensors in the market can be generalized into three categories: the Clamp-on Current Probe, the Rogowski Coil Current Probe, and the Sense Resistor/Shunt Resistor. A comprehensive comparison between these current sensors can be found in
http://literature.cdn.keysight.com/litweb/pdf/5992-2656EN.pdf
What kind of motor are you using? What creates the current ripple and how is the current ripple influenced by by motor production spread?
Reason for the question:
We once (1990s) tried to create an automotive seat positioning system counting motor current ripples (of a 12V DC motors). At that time we learned:
1. The ripple mainly is caused by unintentional asymmetries in the motor.
2. Motor manufacturers want to reduce the ripple having the target of producing no ripple at all!
3. We found motor samples where the ripple really disappeared at certain mechanical loads and rotation speeds.
4. We found motors that have ripple at double the frequency.
5. We could change the shape, spectrum and amplitude of the ripple by mechanical impact on the motor. (sudden blocking of the rotation)
Finally the project was stopped and motor movement was controlled by a magnet on a wheel and a hall sensor. This was more expensive but reliable.
We never tried ripple counting later anymore.
- Badges
- Science method
- Similar topics
- Methodology