Since 1994, the University of Minnesota has been undertaking a long overdue restructuring of power electronics and electric machines/drives courses. This restructuring allows digital control to be integrated into first courses, thereby teaching students what they need to learn, making these courses appealing, and providing a seamless continuity to advanced courses. By a concise presentation in just two undergraduate courses, this restructuring motivates students to take related courses in programmable logic controllers, microcontrollers and digital signal processor applications. This ensures a first-rate education that is meaningful in the workplace as well as in graduate education leading to a research and development oriented career. This restructuring has several components to it. Outdated topics that waste time and mislead students are deleted. To integrate control in the first courses, unique approaches are developed to convey information more effectively. In the first course in power electronics, a building block is identified in commonly used power converter topologies in order to unify their analysis. In the field of electric drives, the use of space vectors is introduced on a physical basis to describe operation of ac machines in steady state in the first course, and to discuss their optimum control under dynamic conditions in the advanced course. Appropriate simulation software and software-reconfigurable hardware laboratories using a DSP-based rapid prototyping tool are used to support the analytical discussion.

Abstracf-Operating a bridge-type PWM switch mode power converter with asymmetrical duty ratios can eliminate switching losses with no increase in conduction loss. This is a new circuit topology that combines the best features of resonant (zero switching loss) and switch mode (low conduction loss) circuits. Design equations for just such a circuit are presented.

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We describe an approach to educating for systemic change in energy systems by integrating technical knowledge of solutions with reflection on paradigms and norms, facilitated by experiential and art‐based forms of learning. The course, “Power Systems Journey: Making the Invisible Visible and Actionable,” is part of the University of Minnesota interdisciplinary grand‐challenge curriculum. Students take on the challenge of public science communication about how to change the electric‐grid system (from power generation to consumption) as part of an energy transition to respond to climate change. The course integrates electrical engineering, history of science and technology, systems thinking, design thinking, paradigms, art, humanities, science communication, storytelling, experiential learning, and the creation of GIS story‐maps and museum exhibits. The design context and elements of the course are described and include: the grand challenge of the energy transition itself, the context of energy‐transition education, the nature of the grand‐challenge curriculum, the collaborative and teaching philosophy, the role of students, the interdisciplinary course framework, the special focus on the role of arts and humanities in energy education, and the course‐curricular structure, which uses the “Earth Systems Journey” curriculum model. The centerpiece of the article describes the “Power Systems Journey” experience in narrative form to match the pedagogical approach of the course using artwork examples from students as they investigated the grid. The article concludes with reflections from students and teachers on what the course offers and where to go from here.

Following the precepts of an ideal dc-dc power converter, the asymmetrical duty-cycle power converter, a zeroswitching loss converter, is, in a demonstrable way, a new direction in dc power conversion. Its benefits include low conduction loss, low EMI generation, and lossless switching. This paper includes conceptual discourse on the nature of the asymmetrical converter, as well as experimental results.

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