Next week, members of Enspec Power’s Consultancy team will travel to Canada for the CIGRE Energy Forum 2026 in Calgary, where Power Systems Engineer Ayesha Irfan will present new research into Transient Recovery Voltage (TRV).
The paper, Assessment of Circuit Breaker TRV Requirements for Passive Harmonic Filters Considering Different Grounding Arrangements, is co-authored with Kerim Ozer and Tim Rastall and will be presented as part of C4 – Power System Technical Performance.
The research builds on previous TRV work at Enspec, developing an earlier case study to look more closely at how different system earthing arrangements can influence TRV requirements.
Why Transient Recovery Voltage studies matter
Transient Recovery Voltage is the voltage that appears across a circuit breaker following current interruption. During normal switching or when clearing a fault, stored energy within the electrical system can produce a fast, high-frequency voltage across the breaker.
A TRV study assesses the voltage that could occur and how quickly it develops, comparing this against the capability of the circuit breaker. This allows engineers to understand whether the selected equipment is suitable for the conditions it may experience in operation.
For Enspec, TRV studies are frequently associated with the design and supply of passive harmonic filters, where the filter is connected behind a circuit breaker. The assessment is not limited to harmonic filter applications, however, and can be carried out for circuit breakers elsewhere within an electrical system.
The timing of this work can also have implications for a project.
Experience from TRV studies undertaken by Enspec has included cases where the assessment has been carried out relatively late, after the circuit breaker has already been selected. Identifying an issue at that point can leave a project needing to reconsider equipment when procurement decisions have already been made.
This is one reason Enspec is increasingly looking at how studies such as TRV can provide greater value when considered earlier in project development.
A return to Calgary
The conference has an additional significance for Ayesha.
Calgary is also Ayesha’s home city.
The presentation therefore brings Enspec’s technical work to a city with a personal connection, while providing an opportunity to share the research with an international engineering audience.
Ayesha first joined Enspec as a placement student while completing a Master’s degree at the University of Liverpool. TRV studies formed part of that work from the placement onwards, before a subsequent move into a full-time role as a Power Systems Engineer.
Speaking ahead of the conference, Ayesha said “the aim is to offer useful technical insight and encourage discussion with other engineers working on similar challenges. Returning to Calgary to represent Enspec internationally adds another dimension to the occasion.”
Other members of Enspec’s Consultancy team including Enspec’s Director of Consultancy Kerim Ozer and Power Systems Intern Seyma Korum will also be attending the CIGRE Energy Forum throughout the week.
Following the presentation, we will share more from the paper and explore the technical findings in greater detail.
