electronic circuits process and control electrical energy, and are critical
elements in many kinds of systems. The rapid evolution
of technology is generating
a demand for power electronics whose capabilities
greatly exceed what is presently achievable. Challenges of particular
importance include miniaturization and integration of power electronics,
and improving their cost and dynamic performance. Miniaturization is difficult
in part because the magnetic components used in most power circuits scale down
poorly in size. Likewise, achieving integration and low cost is difficult
because of the diverse materials and assembly methods that are required
group is working to address these challenges through a combination of new
technologies. One research focus is on the development of improved power
passive components. Passive components such as inductors
and capacitors often dominate the size and cost of power circuits,
and limit their efficiency, noise attenuation, and transient performance.
In one effort, we are developing means to improve the performance of passive
filter components by compensating for their parasitics. These
efforts have led to new integrated filter components with
much better performance than conventional passives. Likewise,
developing new types of power passive components that better scale to small sizes and high frequencies.
Construction of these components using microfabrication techniques is also being
explored, with the goal of enabling integrated fabrication of power converters.
A second research
focus is the development of techniques to achieve greatly increased switching
frequencies in power converters.
Higher frequencies are desirable because they enable faster transient response
and reduce passive component requirements. Moreover, at
sufficiently high frequencies, batch fabrication of many circuit components may
become possible, enabling higher levels of integration to be achieved. We
are exploring new system architectures, circuit designs, and control methods
that together enable substantial increases in operating frequency over the
present state of the art. It is anticipated that the technologies under
development will lead to miniaturized, highly integrated power electronics.
In addition to
developing fundamental power conversion technologies, we are applying them in a
variety of applications. Automotive
power generation and control
is one such area. For example, we have
investigated the application of power electronics to enhance the efficiency,
power, and transient performance of automotive alternators. We have also
developed dc/dc converters and other power electronics for automotive
applications, with the goal of enabling improved performance, safety, and
comfort in vehicles. Other areas of interest include power components and
circuits for industrial, commercial, consumer, and medical applications where
improved size, efficiency, and performance are of importance.