The Closed-Loop Revolution

The year is 1970. An engineer with one of the world's most innovative protective relay developers glides an office chair back toward her desk. She sits in a massive, windowless room lit by high-bay fluorescents; the low hum of fans is the only soundtrack to her work. She checks the system specification again, squints toward the wall behind her, and finally gets up to reconfigure the final components. The perimeter of the room is lined with panels of analogue circuit components - thousands upon thousands in total - and she's spent the better part of a week reconfiguring them. With several other groups waiting to use the analogue simulator, she's been working as quickly as possible. Her motivation is no more than a series of satisfying clicks: the tripping of electromechanical distance protection relays, which will give her team the confidence to provide the technology to a customer in a novel network context. To see the relay operate in response to a true, albeit scaled-down, fault signal in the laboratory environment - that assurance is worth the unprecedented investment in the equipment that surrounds her.