Power and Energy

Power and Energy Research

Power and energy systems worldwide are experiencing major changes in terms of energy generation, transmission, delivery, and distribution. The objective is to evolve the electric grid to enhance system control, reliability, efficiency, and safety. Advanced energy systems and technologies such as renewable sources of energy, energy storage systems, and electric vehicles (EVs) as well as equipment such as sensors, smart meters, and communication devices along with innovations in computing technologies, machine learning, and data analytics are used to modernize the electric grid and the way it is planned, operated, and managed.

Power systems engineering involves the generation, transmission and distribution of electric power.  In recent years, renewable energy sources, such as solar and wind, have been developed and integrated into the power grid. There are new government mandates for electric vehicles development and production. These fast changes create demand for engineers who understand the evolving power grid, the power electronics required to address the changes, and the technologies needed for renewable energy such as advanced solar cells.

Renewable energy technology expects to play an important role in fighting against climate change and global warming by reducing carbon dioxide emissions. Among so many different renewable energy technologies photovoltaics provide a direct energy conversion from sunlight into electricity without producing harmful byproducts or noise. In particular, organic photovoltaics (OPVs) have received great interest in recent years due to the promising potential for the development of large-area, low-cost, light-weight solar modules with highly flexible form factors.

The UW Bothell graduate curriculum includes various courses covering renewable energy resources and associated technologies (B EE 542), power electronics for renewable energy conversions (B EE 550, 555, 557), and smart energy transmission and distribution (B EE 571 and 572). For deeper knowledge, students are encouraged to pursue B EE 600 Independent Study or B EE 700 Thesis with a faculty member.

Career Pathways

Experiences from classes in this key focus area of Power and Energy will prepare students for employment in this industry in several capacities. Students should be prepared for competitive consideration of employment positions such as:

  • Power Systems/Transmission Engineer
  • Smart Grid Engineer
  • Power Electronics Engineer
  • Solar Array Electrical Engineering Engineer
  • Power System Engineer

Faculty in Power and Energy

Harry Aintablian

Seungkeun Choi

Mahmoud Ghofrani

Research at UW Bothell

Dr. Harry Aintablian’s research experience is in power electronics for space systems. At UW Bothell he has supervised several student research projects in power conversion, reliability analyses of electronic systems, and power management of photovoltaic systems with energy storage. His current research involves the development of high-voltage, high-frequency power supplies for electrohydrodynamic applications such as Unmanned Aerial Vehicles (UAVs) and a Covid respirator mask.

Dr. Seungkeun Choi’s research interest focuses on the development of highly efficient thin film solar cells based on organic semiconductors. In organic solar cells, organic light-absorbing active layers are sandwiched between two electrodes with a bulk heterojunction where donor and acceptor materials are intermixed. The optimum active layer thickness for efficient charge separation, based on polymer and fullerene derivatives, is found to be ~100 nm. However, at this thickness, a considerable portion of the incoming light is not absorbed. One way to improve light absorption within the active layer thickness is to adopt light trapping schemes in which the path length of photons inside the active layer is maximized once photons enter the layer. Increased path length increases the probability of absorption of photons and results in increased photo-current generation per incident photon. Dr. Choi’s research utilizes several fabrication technologies to fabricate a highly efficient light trapping structure that can be used for thin-film photovoltaics.

Dr. Mahmoud Ghofrani’s research interest and potential projects: Research areas in power and energy systems can include a wide variety of topics as follows: Renewable integration, Transmission and distribution planning, smart and micro grids, electric vehicles, distributed generation, electric markets. Current and future research projects in these areas include but not limited to: Developing optimization frameworks for distribution system operation with renewable DGs and EVs, Renewable generation forecasting, etc.

Study Power and Energy

The curriculum reflects depth and breadth of faculty research expertise and provides graduate students with a solid foundation in power systems, renewable energy, and power electronics. Relevant courses include:

Learning Objectives

In this technical area, students will learn:

  • Various solar cell technologies by covering renewable energy resources, photovoltaic basics and systems, state-of-the-art solar cell technologies including organic solar cells, and manufacturing advancement.
  • Power electronics fundamentals including characterization of power semiconductor devices, design of magnetic components and filters, analysis and design of AC/DC DC/DC, and DC/AC power converters.
  • Advanced power electronics of a range of renewable technologies including solar, wind and hydroelectric.
  • Electrical machines and drives including dc, synchronous, and induction machines for both motors and generators.
  • Iteration and simulation techniques as well as the numerical solutions required to analyze large-scale power systems.
  • Electric power grid and its operation in the US and introduction of renewable energy generation such as wind and solar energy and their integration into the grid.

Emphasis on Project-Based Learning through Class Projects

Many of the courses listed above provide class projects that will enhance student learning. Particularly, students in a team-oriented project learn important skills such as collaboration, communication, and presentation.

[B EE 542] Solar Cells

A typical solar cell has semiconductors sandwiched between two electrodes. One of the electrodes must be transparent for light to pass through. However, transparent electrode is not generally as conductive as a metal electrode, hence, increasing resistive power loss through the increased series resistance. This resistive power loss becomes significant as the solar cell becomes large. In this design project, students design and optimize a metal grid which will be integrated with a transparent electrode in order to lower a resistive power loss.   

This class contains three laboratory sections to fabricate and characterize organic solar cells. Lab one will fabricate bulk heterojunction organic solar cells. Lab two test and analyze cell parameters. Lab three will characterize the surface morphology and chemical elements.

[B EE 550] Introduction to Power Electronics

In a regulated power supply, the output voltage stays constant even when the load or the input voltage varies. The switching dc-dc converter within the power supply feeds back the output to a control circuit which adjusts the duty ratio of the transistor switch. Adding a feedback loop can cause the converter circuit to become unstable. In this project, students design and simulate a given dc-dc converter with feedback control.  Students analyze the stability of the converter with feedback by a circuit simulator.  Additionally, students design and verify a compensator circuit to obtain adequate phase margin and to extend the bandwidth of the feedback loop.

[B EE 557] Electrical/Power Electronic Systems in Renewable Energy

The project involves researching a current topic in renewable energy electrical and electronic systems and presenting recommendations on how to improve the current research or the current technology.    The project report includes results of the current state of research and recommendations on how to further the research. Students are required to include material from at least seven credible references three of which should be “professional” references such as IEEE journal papers. After completion of the research paper, students prepare a set of PowerPoint charts for a 15-20 minute in-class presentation.

[B EE 571] Power Systems Analysis

Power flow analysis is the most common analysis tool in power and energy systems. It provides a comprehensive picture of the system state by calculating the voltage magnitude and phase angle at each bus in a power system under balanced three-phase steady-state condition. As a byproduct of this calculation, real and reactive power flows in equipment such as transmission lines and transformers, as well as equipment losses can be calculated. In this project, students write codes to implement power flow analysis and demonstrate the applicability and adaptability of the implemented analysis for different IEEE sample test systems.