Control and stability of future power systems with up to 100% renewable generation (FULLY FUNDED)

Supporting company:
Siemens

Supervising academics:
Dr Robin Preece

Student background required:
Interested students should have either electrical engineering, physics, or computer science degrees with good mathematics skills.

Benefit to / Impact on Industry:
In recent years, changes in the energy sector have been driven by a strong growing use of renewable sources, in particular wind and solar energy. Simultaneously, there is a strong trend of phasing out of existing conventional power plants. This rapidly changing generation mix is resulting in decreasing system inertia which requires advanced control solutions to maintain system frequency during disturbances.

What novelty will the student base their PhD on?
There is currently little work on transmission systems operating with low (or no) inertia. The increase in penetration of renewable energy resources and international interconnectors is creating frequency regulation challenges, but also provides fast controllability which could be exploited to solve those challenges – this trade-off needs investigation and will be extremely novel.

Project overview:
Traditional electricity generation uses fuels like coal and gas to make large turbines spin. These systems have large amounts of mechanical inertia which helps to keep the electrical system frequency stable and the system secure and operational. As power systems integrate larger amounts of renewable energy, these power plants are being replaced by low (or no) inertia systems (there is no inertia in a solar cell). This means that maintain a constant steady frequency (which is vital) requires fast active control. As the number of renewable energy sources increases (potentially up to 100%), we will need to completely rethink the way system frequency is regulated and controlled. This project will identify the problems that will occur and develop mitigation strategies to enable secure and safe system operation – ensuring maximum possible renewable energy usage and informing national policy decisions about the future design of the electricity network.

Outline of Proposed Project Plan:
Year 1: Taught courses and preparatory study
Year 2: The second year will focus on developing typical network models for transmission systems with increasing levels of renewable energy source penetration (up to 100%). A wide variety of simulation will then be performed in order to characterise the system response and identify the risks to system security.
Year 3: Year 3 will focus on control design to mitigate the problems identified during the Year 2 studies. This will take the form of extensions to traditional hierarchical frequency control schemes, as well as new control designs focussed on distributed localised control. Potential schemes will be thoroughly evaluated.
Year 4: In the final year, the research will focus on the trade-off between the decrease in system inertia and the increase in controllability on system frequency regulation brought about by increased renewable penetration. Recommendations about optimal system configurations and control schemes will be made.