PD technique monitors motors and generators

Partial Discharge (PD) monitoring is a valuable method of identifying insulation deterioration of generators and high voltage electric motors, reports Rovsing Dynamics. The Denmark-based condition monitoring specialist says it is important to know well in advance that sparking is degrading insulation as repairing HV components dictates long outage time.

PD converters from the Swiss company PDTech convert high frequency sparks occurring between HV parts into signals measurable by Rovsing Dynamics’ OPENpredictor system, which can monitor, trend and forecast the PD levels so that appropriate diagnosis and inspections can be scheduled.

The PD levels depend on load and winding temperature conditions and must therefore be interpreted with care. OPENpredictor’s reportedly unique pre-classification methodology is used to create comparable process circumstances for trending, warning and forecasts of PD levels.

An instantaneous AutoDiagnosis facility automatically warns of increased PD levels for similar operating conditions, indicating the need for detailed diagnosis to identify the root cause. This is executed with an offline partial discharge analyser, also from PD Tech. Based on the results, an inspection of the affected parts can be scheduled. MP