The traditional operational limits established through static transmission line rating methodologies are dependent on several volatile environmental variables identified in IEEE Standard 738-2006. The current common practice for transmission line rating is to select conservative values for these environmental variables within the standard that would equate to a low probability that conductor sag will exceed those operational limits for a very short duration.
This methodology acknowledges that operational limits of transmission lines are often conservative and inherently accepts the operational risk of a relatively low probability of exceeding the established static ratings. The implication of this methodology is often significant transmission grid congestion, resulting in bottlenecks that limit the system operator's ability to transfer power. The weaknesses of this methodology and the need to evolve to a true dynamic line rating methodology have been recognized for many years without a viable and comprehensive solution being available.
The SMARTLINE solution is a new comprehensive dynamic line rating and forecasting solution that resolves the challenges that have prevented grid operators from maximizing transmission line power-transfer capabilities. The SMARTLINE system is a turn-key dynamic grid management solution comprised of an accurate and durable direct spot LiDAR monitoring device, plug-and-play communications systems, expert line rating engineering and a secure comprehensive IT server solution for monitoring and forecasting system capacity. The solution can be fully deployed hot, without the need for difficult and costly outages. The solution also provides a suite of valuable data and analytics that can be used for fault analysis and a variety of line condition monitoring protocols as well as comprehensive transmission system asset management.
The ultimate goal and benefit of using SMARTLINE ratings are realized by the ability to provide accurate and reliable 24- and 48-hour forecasts, which allow a transmission operator/planner to accurately understand the conductor sag and temperature relationship, then analytics correlates the results with the related forecasted load and weather to produce predictable and consistent forecasts. This will allow a utility, ISO or RTO to utilize the full capacity of their transmission facilities.