A team of researchers at Sandia National Laboratories has created a computer model designed to help grid operators quickly restore power to the grid after an outage.

According to the Sandia scientists, the model combines restoration optimization models and computer models that illustrate how grid operators make decisions when they don't fully know each generator and distribution line.

The researchers say the model provides insight into how individual generators, distribution substations and transmission lines respond during the restoration of power.

The model can also simulate black starts triggered by disruptions such as successful cyber attacks.

When it comes to optimizing power restoration, the model evaluates the grid and its components to determine how to restore power as quickly as possible, said Sandia computer scientist Bryan Arguello.

An example of an optimal approach might be to start substation A with generator 1, Arguello said. Once substation A is energized, generators 2-4 can be safely started. These in turn will provide power to substations B, C and D, as well as some critical infrastructure such as water purification plants or district hospitals. Once substation D is energized, power plants 5-8 can start, and so on until the entire grid is restored.

Once a power restoration plan is developed, an algorithm compares it to physical constraints to determine if the plan is feasible, Arguello said. The process is based on a similar model created by researchers at Lawrence Livermore National Laboratory and the University of California, Berkeley.

"The challenge here is to bring in the right amount of information so that the model can make an informed decision without getting bogged down in too much detail," Arguello said.

According to the researchers, the model can also accurately approximate alternating current, which they say is more complex than direct current. The model also provides a more accurate representation of the grid during severe disruptions such as black start conditions.