Could a cable failure shut down your HV asset?
A taste of the technical presentation to be delivered at Mainstream Conference, Melbourne, August 2-3, 2023.
When you think of critical electrical assets, feeders and switchgear are often the second-class citizens, that connect the ‘sexy’ big machines, transformers, and generators.
However, the health of your feeders and switchgear is a critical element of maintaining your network optimum health and reliability.
In this article I will explore the critical assets, present an approach to effectively monitor their condition, and the importance of creating comprehensive testing strategies.
Pic 1: Failed 11kV cable due to installation issuePic 2: Cable termination damaged ot spot within the cable sheet connectionPic 3: Partial discharge within a 33kV AIR insulated switchgear due to bad installationWhy Are Cables and Switchgear Critical?
Cables and switchgear are indeed critical components in any healthy electrical asset.
Their significance lies in their responsibility to carry heavy loads and distribute power efficiently. The importance of individual cabling components is determined by factors including redundancy in the system. Redundancy is of course necessary to provide backup options in case of failure.
These assets are also critical for the online detection of issues within other electrical assets. In fact, useful information, in form of high frequencies currents, propagates through the network via cables and switchgear.
How to Plan for Effective Condition Monitoring of the critical assets?
To ensure the reliability and longevity of any electrical asset, an effective monitoring system is essential.
Here an approach for an effective condition assessment:
1. Categorise your assets
The first step is to accurately classify the assets based on their type, characteristics, and criticality to prioritise your testing/inspection schedule.
2. Identify failure mechanisms
Next, understand potential failure mechanisms, which can exist into the different assets due to design and asset characteristics.
3. Define test schedule
Then, you’ll need to establish a test schedule that fit the operational needs consider the asset criticality and is capable of measuring benchmark for the identification of the different failure mechanisms.
4. Define the testing criteria
To properly interpret the test results, criteria have to be developed for each test, considering international standards, asset life stages, and most importantly expert knowledge. Plus, an overall-criteria has to be developed to rank the different assets on the network.
5. Implement a follow-up strategy
Finally, based on the results analysis, implement an appropriate follow-up strategy to address any issues identified by the condition assessment.
In the full presentation for Mainstream Conference 2023, I will go through in some detail the challenges you’re likely to face when monitoring your assets and how to develop a comprehensive evaluation criteria for optimum asset health and comparison.
To sum up, cables and switchgear are often the unsung heroes of HV electrical system. Understanding their health is vital for the reliability of the network to provide continuous operation and to monitor the connected assets.
By implementing an effective monitoring strategy and comprehensive evaluation criteria, potential failures can be identified and addressed proactively. With proper monitoring and timely actions, you can ensure the longevity and efficiency of these vital components, reducing the risk of unexpected failures and enhancing overall system reliability.
Luca Gargnani will be speaking in depth about managing cable failure and asset reliability at Mainstream Conference 2023.
COO-OptMonitor, Luca Garagnani.
Luca Garagnani holds a Master’s Degree in Electrical Engineering with particular expertise in Partial Discharge Testing.
His experience has centered around the measurement and analysis of MV/HV cables, transformers, switchgear and rotating machines throughout Europe, USA, Asia, and the Middle East. He also regularly conducts teaching and tutoring on the theory of partial discharge, monitoring and measurement techniques.
Pic 1: Failed 11kV cable due to installation issuePic 2: Cable termination damaged ot spot within the cable sheet connectionPic 3: Partial discharge within a 33kV AIR insulated switchgear due to bad installation