Protecting power grids from cybersecurity breaches

As physical infrastructure such as power grids increasingly become smart – that is, connected and online – researchers are working to mitigate vulnerabilities and protect the systems from cyberattacks.  

Ryerson engineering professor Reza Arani is the Canada Research Chair in Smart Grid Cyber-Physical Security. As part of his research, he is working on strategies to prevent cybersecurity breaches like the one in Ukraine in 2015, when hackers targeted three power distribution centres and left about 230,000 residents without electricity. He is seeking to improve the resilience of physical infrastructure, such as improving cybersecurity or ensuring that new sustainable energy sources like wind power can effectively integrate with power grids. 

Professor Arani and his collaborators were the first to examine synchronization systems used in power microgrids for vulnerabilities and shared their results in a recent publication. Synchronization systems play an important day-to-day role in electricity systems, says professor Arani. They help connect different power grids to each other, sending communications signals to generators to match frequencies with the other grids and optimizing performance. Microgrids are smaller sections of a wider power system that can be separated from and later rejoin the main grid, synchronizing frequencies once reconnected. He says protecting microgrids from disruption is particularly important in contexts such as maintaining electricity for sensitive users such as hospitals, which often have their own microgrids. The researchers looked for vulnerabilities by creating a realistic simulation based on an existing medium-voltage distribution system in Ontario.

Their research found that the synchronization systems could be hacked. These systems are vulnerable to attack through false communications signals that would interfere with the power generator by sending unauthorized instructions.  Through their research, they discovered the patterns in these false signals are quite different from the patterns of legitimate signals sent as part of the system’s routine operations. 

To counter such attacks, the researchers developed two strategies based around these signal pattern differences. The first relies on data analytics to detect the types of signal patterns that would be used for sending false instructions and trigger an alarm. The second, professor Arani explains, is more straightforward: modifying the generator’s synchronization control mechanism to remove the vulnerability. That way, manipulated content would not harm the generator.

These mitigation strategies mean that even if the hackers bypass the cyber defence mechanism and get access to the system, disruption would be still prevented. “What we have done there is the last line of defence. We assume they’ve gotten access to the communication system as they want, but we want to make sure that even if they’ve got access to the parts they want, if they can intrude in our system, that still, there is no vulnerability for them to exploit,” said professor Arani. He is continuing to research this area, examining the cybersecurity of additional aspects of the power system to develop holistic solutions.  

Professor Arani and his collaborators, Amr S. Mohamed and professor Deepa Kundur of the University of Toronto and Amir Abiri Jahromi of the University of Leeds, published their findings in the prestigious journal IEEE Transactions on Smart Grid (external link, opens in new window)  earlier this year. 

October is Cyber Security Awareness Month in Canada. (external link, opens in new window) 

Related links:

Collaborating with industry at the leading edge of cybersecurity research (October, 2020)

Using big data and virtual reality to plan for connected and autonomous vehicles  (October, 2020)

Rogers Cybersecure Catalyst