IEEE Power & Energy Magazine - March/April 2021 - 63

Vision for a New Operational Paradigm
The analysis of recent grid events and trends in system
operation demonstrate that improvements in the current operational philosophy, or even a new philosophy,
are needed to ensure power system security in an everchanging environment. In this section, we discuss elements that shall have a central role in a new successful
operational paradigm.

analytics can be applied to evaluate the effectiveness of historical remedial actions. A possible approach would start
with assessing the accuracy of the congestion forecast tool
and proceed with analyzing and classifying historical grid
snapshots. More precisely, for each grid snapshot with security violations, the goal would be to determine the root cause
such as 1) no congestion warning was issued due to poor
forecast quality of generation and/or load; 2) congestion
was correctly predicted, but the selected remedial action
turned out to be inefficient; and 3) congestion was correctly
predicted, but there was no available remedial action to
mitigate the insecurity event. This analysis can help a TSO

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Redispatched Energy (GWh)

Finally, there have been several recent grid situations
where avoiding N−1 violations by applying separated busbar
operations in several substations would lead to a low degree
of connectivity in the transmission grid. In the worst case
after a busbar operation, if a substation is connected to the
rest of the grid with only one transmission line, the unexpected tripping of this line (e.g., a lightning strike) would
cause the loss of the substation and the interruption of supply
in the underlying distribution grid.
To summarize, the number of remedial actions against
N−1 or voltage violations has been increasing over the last
years, which increases the burden on the system operators in
the control room. As mentioned earlier, remedial actions are
mostly determined based on experience and rules of thumb
derived from simulation-based approaches. We believe that
system operation would benefit from a DSS that provides the
operators with suggested remedial actions against N−1 and
voltage violations. More importantly, the DSS could efficiently account for possible undesired side effects of actions
against one problem (e.g., N−1 violation) on other operational criteria (e.g., voltage profiles and degree of transmission network connectivity).

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CH-Decrease
CH-Increase
International-Decrease
International-Increase

Analytics and Visualization

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figure 5. The trend in redispatched energy due to remedial actions. CH: Swiss national.

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International
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Number of Days
With Redispatch Actions

Secure power system operation requires taking fast and
effective actions under critical grid conditions. Typically,
many alarms are displayed on the large monitor of a TSO
control center in case of a grid event. In some cases, the
system operators must visually process this information
and identify the most important alarms. Analytics and
artificial intelligence applied to real-time monitoring data
can help classify the alarms into first priority (for example, alarms associated with the root cause of an event) and
second priority (for example, alarms activated as a consequence of other alarms). Such methods, in combination
with modern visualization approaches that, for example,
display the alarms according to their assigned priorities,
can help the operators obtain valuable insights into the
ongoing grid conditions and increase their reaction speed.
Moreover, algorithms running on monitoring data could
help predict imminent grid events and provide recommendations of remedial actions to the operator to further
reduce the reaction time.
Automated ex-post data analytics can help identify the
root causes of past events of grid insecurity, learn from
them, and better prepare for the future. For example, ex-post

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figure 6. The trend in the number of days per year when
redispatch actions were implemented.
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IEEE Power & Energy Magazine - March/April 2021

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