Monitoring Parameters for Large Electrical Machines

The critical nature of large electrical machines justifies continuous monitoring using several complementary techniques.

Predictive techniques applicable to large electrical machines are one of the areas where researchers are focusing most of their attention in order to develop predictive technologies that are easy to implement and offer more reliable diagnostic capabilities:

• Air gap. Air gap control during operation is a measurement technique that uses capacitive sensors immune to eddy current induction. This technology has been around for about 10 years, and there are more than 400 “online” installations in large-scale hydraulic alternators and turbines.
• Air Gap Flux. This is an inductive measurement system used to detect eccentricity issues in turbo-generators and short circuits in the windings of salient-pole machines.
• Stator Bar Vibrations (SBV). Based on capacitive sensors, this technique monitors the vibration of the bars inside the stator slots of alternators to prevent fatigue-induced dislodgement.
• Coil Head Vibrations (EWV). This technique uses fiber-optic accelerometers for predictive monitoring of vibrations in coil heads, to prevent insulation breakdown due to fatigue and the resulting electrical discharge.

Contact one of our engineers specializing in predictive maintenance for advice on monitoring parameters for large electrical machines: info@preditec.com