By early 2002, it remains clear that utility investments related to substation automation and integration programs remain underfunded on a global scale, but nowhere is this more apparent than in North America. This situation has several plausible reasons, including:

• 2001 utility focus on shoring up transmission infrastructure to prepare for deregulation.
• Continued uncertainty in many states and provinces regarding deregulation legislation and a lack of uniform application of performance-based rate structures.
• Complexity and cost of substation refurbishment projects versus the new substation construction situation. (The United States and Canada have about 70,000 utility-operated substations, and add/replace only about 1200 per year.)
• Perception among upper management that automation benefits are largely qualitative, not quantitative. Some still fear losing their investments to restructuring, with an uncertain future for such asset ownership.

Nonetheless, most large utilities around the world are making some progress with substation automation activities, be it in a slower phased approach, or limited to the integration of currently installed equipment, or forging ahead with complete automation solutions.

RTUs with PLC Capabilities

As the table illustrates, more than 50% of the officials in a recent study indicated that their utility had installed remote terminal units (RTUs) with programmable logic controller (PLC) capabilities into one or more of their substations. While only a few utilities were using PLCs simply as replacements for RTUs, more than 40% were using PLCs to enact or initiate process automation sequences at the substation level.

The applications these PLC-like RTUs performed included feeder reconfiguration, VAR/voltage control, capacitor control, reclosing and some additional local control.

More than 40% of substation officials are indeed making some use of “non-traditional” information derived from the automation of their substations. Many respondents provided specific mentions of such use of substation data. Breaker condition monitoring, fault distance information, transformer loading and intelligent alarming were among the “individual” uses provided.

Concerning any use of other advanced technology equipment installations, officials indicated that they had already been using such equipment in their substations prior to the current automation project. Digital fault recorders (DFRs), multifunction meters and large power transformer monitors all were frequently mentioned.

Substations Communications RTU and PLC Findings	Percent Indicating
RTUs having PLC capabilities	56%
PLCs used to enact process or information automation sequences at substation level	42%
PLCs being used to replace RTUs	8%

Establishment of a Cross-Department Team

Many utilities are finding that the only way they can successfully address the concerns of would-be substation-data users is to assemble a cross-department team to deal with the substation technology upgrade program. Among utilities that had taken this “cross-functional, interdepartmental” approach, most indicated that these empowered teams were a help in ensuring the success of the substation technology upgrade program, not a hindrance.

The findings reported here suggest to me that a “piece-meal” (equipment- or problem-specific) approach to substation automation may be all that many utilities can undertake at this time, given an era of tight budgets, limited staff and some degree of management indifference.

Nonetheless, it is important to take note that many utilities are attempting to address their weakest-performing links in or around the substation, whether that is fault identification, transformer diagnostics, accurate power metering or any other substation-related activity.

The final point to note is that each step forward in substation integration involves data communications, and thus becomes an enabler for remote access to field operational data, whether this is piecemeal or substation-wide. If properly implemented, each step will whet the utility’s appetite for further progress in substation automation and integration.