Direct Measurement of Rotational Rate of Asynchronous Electrical Submersible Motors for Oil Production

One considers the measurement of the rotationrate of the asynchronous submersible electrical motors (SEM) by placing on its shaft on dielectric beams located at the two end sides of k non-magnetic intermediate bearings of the rotor of 4k four-pole magnets with radially magnetized zones of different polarities, oriented strictly to the same direction. Measuring information is generated directly by SEM stator winding and is transmitted to the surface via a power cable and is removed through the current transformer and a bandpass filter from the cable line phase. The results of circuit simulation are presented in software package confirming the validity of the measuring data.