Condition Monitoring of Variable Speed Drives

Predictive maintenance through condition monitoring can help to improve availability of critical assets such as variable speed drives (VSD). It provides a view on the health of assets with early warnings of developing issues to take timely, corrective actions. This can unlock a shift from unplanned to planned downtime, or even avoid downtime altogether and optimization of asset maintenance cost. Condition monitoring of VSDs entails real-time monitoring of critical signals available in VSDs such as thermal, electrical, and mechanical signals which are collected from discrete sensors or estimated signals. Key Performance Indicators (KPIs) are generated by passing collected signals through specific algorithms followed by trending them with respect to time. The deviation of KPI trends is observed continuously between the healthy system and the system with fault. Typically, KPIs are related to bearing temperatures, cooling system, I/O filters, DC bus voltages, Auxiliary system, CPU temperature etc. Monitoring of KPIs for VSDs aids users to identify sub system fault before it propagates to entire system, providing sufficient time to plan corrective maintenance.