A Medium-term Vision for Grid Controls
By Anuradha Annaswamy
A new report from IEEE, “Vision for Smart Grid Controls: 2030 and Beyond,” explores what is implied by a power system that can gather any and all available information, facilitate the functioning of resilient transmission and distribution networks, shape any and all loads that are responsive, and allocate all dispatchable generators, storage and electric vehicles to deliver reliable and affordable power everywhere and at all times.
The traditional roles of control in power grids have been largely confined to the regulation of frequency and voltage, and reactive power control. With the ushering in of the smart grid, roles are significantly enlarged, with drivers ranging from environmental concerns, growing energy demand and increasing electrified transportation to aging infrastructures and empowerment of consumers. Whatever the future scenario is thought to be, whether it involves a radical redesign of the entire power system or consists in overhauls of specific areas—markets, demand-response systems, microgrids, transportation, distribution, transmission, renewable generation—loci of control will emerge and expand in new ways and in new contexts.
Thus, full realization of a cyber-enabled transformation of the electric power system requires a vision that encompasses controls. Without their further development, it would be impossible to design and build a smart grid that can gather any and all available information, facilitate the functioning of resilient transmission and distribution networks, shape any and all loads that are responsive, and allocate all dispatchable generators, storage and electric vehicles to deliver reliable and affordable power everywhere and at all times.
A new report from IEEE, Vision for Smart Grid Controls: 2030 and Beyond, explores this vision. Produced by a group that I led, the report starts with a snapshot of the current status of controls in power grids and drivers that are producing a transformation, and proceeds to possible scenarios that can emerge and the associated control-centric research challenges.
“It is not an exaggeration to claim that every system and process in the future grid—from operation planning to unit control, from generation to end-user consumption, with dynamics ranging from years to milliseconds—will be influenced by some aspect of control,” says the report. Sections of the report describe innovations in the traditional subsystems of generation, transmission, and distribution; emerging roles in areas the smart grid has opened for a control-oriented perspective and solution; and a controls perspective across the entire grid, requiring new approaches and paradigms. Yet another section discusses “possible game changers that could result in a radical re-architecting of the grid, leading to a grid with a huge number of active endpoints, collectively achieving the desired goals of power delivery and a self-healing grid that responds, corrects, and restores power delivery following any anomaly."
To achieve the transformations envisioned in the electric power grid, it is clear that the following objectives have to be met:
- enable integration of intermittent renewable energy sources and help decarbonize power systems,
- allow reliable and secure two-way power and information flows,
- enable energy efficiency, effective demand management, and customer choice,
- provide self-healing from power disturbance events, and
- operate resiliently against physical and cyber-attacks.
It is these objectives that necessitate an increased deployment of feedback and communication, which in turn implies that loops need to be closed where they have never been. These feedback loops have to be designed and implemented across multiple temporal and spatial scales, thereby creating a gold mine of opportunities for control. With able support provided by advances in ICT and in power electronics, research investigations need to be launched in new methodologies for transmission, distribution, renewable energy and storage; new roles in emerging topics such as electricity markets, demand-response, microgrids and virtual power plants; and new solutions for efficiency, heating and cooling, and security all of which are needed to provide a blueprint for smart management of information.
Examples of investigations could include enhancements to wind forecasting; power regulation markets that would enable wind energy, when curtailed, to participate in the regulation of grid frequency; and development of computationally efficient distributed architectures for transient stability with suitable redundancies that ensure protection to communication lapses and cyber-attacks; design of intra-day markets and market mechanisms that incorporate storage and PHEV costs; control methods that enable transitions from one operational mode to another in a microgrid, while maintaining balances between generation and loads; dynamic aggregation of a large number of small-scale production units and of consuming units; and modeling of various attack vectors as well as detection and mitigation schemes at all vulnerable points in the grid.
Such examples and more can be collected under the rubric of a system of systems, necessitating new control themes, architectures and algorithms. They in turn must acknowledge the inherent complexity of the grid: large-scale, distributed, hierarchical, stochastic and uncertain. With information and communication technologies and advanced power electronics providing the infrastructure, these architectures and algorithms will need to provide the smarts, and leverage all advances in communications and computation. Together, they usher in new horizons for control, such as building interfaces to social sciences including economics, sociology and psychology. And they provide a blueprint for critical infrastructure systems not only in energy but beyond, such as networks in water, transportation, health-care and biology.
Anuradha Annaswamy, an IEEE Fellow, is Director of the Active-Adaptive Control Laboratory and a Senior Research Scientist in the department of mechanical engineering at MIT. She received the doctorate in electrical engineering from Yale University in 1985, and taught at Yale and Boston University before joining the MIT faculty. Her research interests pertain to adaptive control theory and applications to aerospace and automotive control, active control of noise in thermo-fluid systems, control of autonomous systems, decision and control in smart grids and co-design of control and distributed embedded systems. She is a recipient of best paper awards from the IEEE Control Systems Society, NSF's Presidential Young Investigator Award, the Hans Fisher Senior Fellowship from the Institute for Advanced Study at the Technische Universität München, and the Donald Groen Julius Prize from the Institute of Mechanical Engineers.