With a total installed capacity of 36,912 Megawatts, Hydro-Québec provides a clean, renewable and reliable supply of electricity to all Quebecers. It also sells power on wholesale markets in northeastern North America. The company’s substations play a key role in controlling power flows. For example, they divide long lines into smaller sections, which helps to minimize any disruption to the continuity of service when a section is not functional, such as during a fault or maintenance period.
The various components found in a substation include instruments for measuring current and voltage, protective equipment such as circuit breakers for interrupting a line’s current, control devices, and disconnect switches which are used to switch energy from one line to another almost instantaneously when sections are out-of-service.
Savoie supervises 45 engineers and 35 technicians as well as several external engineering firms who are responsible for substation design. In the past, engineers created and maintained well over 1,000 wiring diagrams and panel layouts for substations by selecting symbols to represent equipment and snaking cables through the diagrams to connect them together. They created parts lists and cable lists by entering each part on a spreadsheet as they added it to a drawing.
The first pass usually went relatively smoothly but the process got more complicated when changes were required. For example, if space was tight, simply adding a cable that stretched from one sheet to another might require considerable redrawing of both sheets to make room for the new cable. Moving a component required moving all the cables connected to that component and reconnecting them in the new location. In some cases, these cables might pass between numerous drawings and each of these drawings had to be located and updated to properly implement the change. Each change to the wiring diagram required a corresponding change to the parts list and cable lists and this was easy to overlook or enter incorrectly, leading to inconsistency between drawings and costing time and effort finding and correcting the errors.