Digital Tools Approach Based On ‘Gerun’ And Online Partial Discharge Monitoring Project To Resolve Alternator’s Failure

Abstract

There is no online monitoring system and digital tools to monitor generator gas turbine healthiness led to generator failure caused un-planned outages resulted power import and penalty chargers. Maintenance program for generator is based on time-based method. Since 2016 to 2020, Asset Team spent millions of ringgit Malaysia for generator rectification and incurred power import cost due to the failure. To overcome the tripping issues, Generator Health Monitoring System was initiated as a research/pilot project as tools to monitor healthiness of Gas Turbine Generator. This project was categorized as digital transformation initiative (Revolution 4.0) as to enable online monitoring & performing diagnostic & prescriptive. The initiative consisted of 2 main pillars which are Generator Rotor Unhealthiness Notification (GERUN) and Online Partial Discharge Monitoring System (PD ONLINE). The aim of this paper is to share the experience in monitoring, economical way, diagnosis, condition evaluation, and possibility of predicting the performance of the generator. The methodology of the Generator Healthiness is to monitor the real time performance of the generator during running condition through rotor thermal losses, ratio of excitation current over the real output power and stator partial discharge pattern. This real time monitoring can improve the maintenance strategy and planning. As a result, plant’s OEE can be increased, reduce the MTBF and more importantly the repair cost. The parameters have been introduced to prevent the generator sudden failure event and bridge the gap condition monitoring especially on the generator part. Arriving to the objective, this project was categorized as digital transformation initiative (Revolution 4.0) as to enable online monitoring & performing diagnostic & prescriptive. The initiative consisted of 2 main pillars which are Generator Rotor Unhealthiness Notification (GERUN) and Online Partial Discharge monitoring system (PD ONLINE) project. Diagnose & prescriptive and provide asset owners with insights on alternator’s health, subsequently prevent unforeseen failure in real time and prescribe operational mitigations to prolong alternator’s life. Recommends targeted test and maintenance (3rd level maintenance predictive) addressing the exact health issue of the alternator value creation & cost saving by eliminating tripping, scope reduction for major inspection, non-dependable on FSR, internal troubleshooting and etc. The system has been implemented across gas processing and utilities Petronas Gas Berhad for 14 units of gas turbine generator. In view of the success implementation, this digital tool will be duplicate to others Petronas Operating Unit.