Synchronous machine induces vibrations causing trips of other machines on the same rail

Borsig-D Compressor Motor (Synchronous Machine-16MW) induces vibrations approximately 10 seconds after startup, which causes a trip on Borsig-A Compressor Motor(on the same rail@10kV) but does not affect Borsig-C Compressor Motor(on a different rail@10kV). 

This suggests an electrical phenomenon rather than a mechanical connection as the root cause. Potential causes include voltage dips, synchronization issues, frequency fluctuations, excitation instability, or harmonic distortions.

Key Points:

1. Observation:
   • The vibration starts 10 seconds after Borsig-D Compressor Motor is energized, indicating a delayed electrical buildup or interaction.
   • Borsig-C Compressor Motor: No vibration (on a different rail).
   • Borsig-A Compressor Motor: Trips due to vibration (on the same rail as Borsig-D Compressor Motor).
2. Hypotheses for Root Cause:
   • Synchronization Issues: Rotor alignment delays during Borsig-D Compressor Motor’s startup may create transients in the shared electrical system.
   • Voltage Dips or Frequency Fluctuations: Transient instability during Borsig-D Compressor Motor’s startup could propagate to Borsig-A Compressor Motor.
   • Excitation System Instability: Poor control of reactive power or field flux may cause oscillatory behavior.
   • Harmonic Distortions: Harmonic or transient electrical disturbances from Borsig-D Compressor Motor could affect sensitive circuits on the same rail.
   • Sensitivity of Borsig-A Compressor Motor: Overly conservative vibration monitoring or trip thresholds might cause unnecessary trips.

Borsig A, B, C and D are Centrifugal Nitrogen Compressors and the Borsig A, B, C, D Compressor Motors are driving these compressors.

We are looking forward to hear from either solution providers or technical experts that can support to mitigate the issue.