Case Study: Sharing an Alternating Current Mitigation System

An alternating current (AC) interference study was conducted in 2019 following a utility development with a new substation and 24 km of powerline upgrades in Alberta, Canada. The study comprised six powerlines by one utility and eight pipelines by two operators. Computer modelling showed voltage hazards under steady-state and fault conditions, susceptibility to AC corrosion, and high coating stress in the unmitigated state. A shared AC mitigation system was designed to eliminate these hazards while reducing mitigation requirements, site visits, construction footprint, environmental impact, and project costs. This article describes the design, installation, commissioning, and benefits of the shared mitigation system.