“When I was a student in Taiwan, I spent a fortune on an engineering calculator for classes and bid farewell to the slide rule,” laughs Chen-Ching Liu, director of the Power and Energy Center (PEC) and American Electric Power Professor of Electrical and Computer Engineering. “The new computer science concept gave me a vision that computers were going to shape the future,” he adds.

A long way from that early vision that sparked his interest in engineering, Chen-Ching Liu was recently elected to the National Academy of Engineering (NAE). This is one of the highest honors for engineers in the United States and recognizes a lifetime of achievement.

In conferring the honor, the NAE cited Liu’s “contributions to computational methods for power system restoration and cybersecurity.” He has spent his career improving the resilience of power systems by studying how they should be operated under abnormal conditions such as outages and disruptions.

Members of the NAE are charged with promoting the engineering profession and offering guidance to government leaders. They are nominated and elected by other NAE members. In the 2020 class, 87 engineers were admitted.

Ahead of the Curve

When Liu was first exposed to computers as a student at National Taiwan University, they took up entire rooms and served exclusively as computing machines. He saw firsthand how computers and microprocessors drove the expansion of the electronics industry, and understood their potential to transform everyday life.

He moved to California to pursue his doctorate in electrical engineering and computer science at the University of California-Berkeley, which he completed in 1983. “I was attracted to artificial intelligence in the ’80s,” he says, “when it was turning from computer science concepts to engineering tools such as expert systems, fuzzy logic, and neural networks. The pursuit of new artificial intelligence and other computational tools for power engineering kept me occupied for the next 30 years.”

Now AI-inspired functions have become a mainstay of power systems research. Throughout his career, Liu has led his field by anticipating the needs of the grid.

Resilience

Liu’s research in recent years has focused on improving power systems’ resilience, or their capacity to fend off and compensate for threats. 

In one of his ongoing projects, he is helping develop microgrid technologies that can be deployed after disasters in areas that have lost power. Catastrophic outages caused by Hurricane Maria in Puerto Rico in 2017 demonstrated the urgency of this effort: areas with no electricity for months struggled to provide medical care to at-risk populations, resulting in otherwise preventable deaths.

“The purpose of resiliency,” Liu explains, “is to make sure the system has embedded energy resources to continue serving the critical load such as hospitals if the power grid is wiped out. We can build a microgrid with local generators and perhaps renewables and battery storage that will be able to serve critical load until the utility comes back online.”

Despite the value of this technology, the dynamics of such small systems have not been studied in depth. “With a small generator trying to pick up a hospital’s load, the relative impact on the system is high,” Liu observes. “So, you have to figure out a way to make sure this tiny power system can provide the frequency and voltage you need. You need more careful analysis and more careful control to be able to keep that tiny power system stable. ”

A major obstacle to deploying microgrids in large scale, however, is their cost. “Microgrids are perceived to be expensive,” Liu explains, “So it’s important to lower cost and improve performance.” 

To achieve this, Liu is developing building blocks for microgrids with researchers in PEC and the Center for Power Electronics Systems (CPES). “The idea is to have a building block that handles power conversion, which is the power electronics function, and also control and monitoring functions, which would be the cyber-physical system function.” Having a single standardized component to integrate these functions would make it less costly, and less complicated, to build, install, and maintain microgrids. The project is supported by the Office of Electricity, Department of Energy, through Pacific Northwest National Lab.

Physical Damage from Virtual Attacks

Liu’s other current research focus is improving the cybersecurity of the power grid. Here again, his research has been prescient, anticipating events that broke into the headlines in recent years. In 2015, hackers took control of the power grid in Ukraine and sent commands that left over 230,000 people without power for several hours. They also overwrote firmware and disrupted remote functions, which meant engineers had to operate circuit breakers manually at more than a dozen substations. 

“Today, the power grid has this information technology and communication system on top that collects all the data, does all the computation, and delivers control commands to the right area of the power grid,” explains Liu. “It’s not just an electrical system anymore, it’s a cyber power grid.”

“The new challenge,” he explains, “is that this cyber system is so critical for monitoring and control that cyber intrusions and cyberattacks can do damage to the physical system.” For example, hackers like those that attacked Ukraine’s power grid could target substations and falsify a command to open all the circuit breakers, causing a widespread outage and damaging costly equipment.

“How can we plug that hole?” asks Liu, “We have to make sure these falsified commands will be captured before they hit the physical grid. It has to happen in the cyber system, so we don’t have much time to find it and stop it. We have milliseconds for the new cyber security technology to identify the problem and kick out the intruder.”

Always Looking to the Future

With decades of experience in his field, Liu is well-positioned to see where power systems research is headed next. Information technology, renewable energy, battery storage, and flexible load are the areas he expects to transform power grids in the coming decade. 

“When I think back, the challenge when I began was more about developing new technologies; the grid itself was changing fairly slowly. But, when you look at the power grid today, all these major fundamental changes are taking place. There’s no shortage of new research challenges for the future,” he laughs.