_{Professor emeritus of power electronics, University of Tennessee, Knoxville, D. Phil, Calcutta University.}

_{Grainger Professor of Power Electronics and Electrical Machines Emeritus, University of Wisconsin-Madision, Ph.D. University of Wisconsin-Madision.}

Power electronics is a sub-field of electrical engineering that deals with the design, control, and conversion of electrical power. It involves the use of electronic devices, such as semiconductors, to efficiently convert and control electrical energy. Power electronics is a rapidly growing field with a wide range of applications in areas such as renewable energy, transportation, and industrial automation.

One of the main areas of study in power electronics is power converters, which are devices that convert electrical energy from one form to another. This includes devices such as rectifiers, inverters, and DC-DC converters, which are used to convert AC to DC, DC to AC, and to change the voltage level of DC. This is useful in applications such as renewable energy systems, electric vehicles, and industrial automation.

Another important area of study in power electronics is power control. This involves the use of electronic devices and control techniques to control the flow of electrical power. This includes devices such as thyristors, transistors, and gate-turn-off thyristors, which are used to control the flow of electrical power in different applications.

A third area of study in power electronics is power quality. This involves the study of the behavior of electrical power systems and the impact of power electronics on power quality. This includes the study of power harmonics, power factor, and power disturbances, and how power electronics devices can be used to improve power quality.

A fourth area of study in power electronics is power transmission and distribution. This involves the use of power electronics devices to improve the efficiency and reliability of electrical power systems. This includes the study of high-voltage DC transmission, flexible AC transmission systems, and the use of power electronics in the smart grid.

A fifth area of study in power electronics is renewable energy systems. This involves the use of power electronics devices to convert and control renewable energy sources such as solar, wind, and hydro power. This includes the study of power electronics devices such as solar inverters, wind power converters, and hydro power converters which are used to convert the energy from these sources into usable electrical power.

A sixth area of study in power electronics is electric vehicles. This involves the use of power electronics devices to convert and control the electrical energy used in electric vehicles. This includes the study of battery management systems, electric motor controllers, and charging systems for electric vehicles.

A seventh area of study in power electronics is the integration of power electronics into industrial systems. This involves the use of power electronics devices to improve the efficiency and reliability of industrial systems. This includes the study of power electronics devices such as variable frequency drives, uninterruptible power supplies, and motor control systems.

Finally, an eighth area of study in power electronics is the energy storage systems. This involves the use of power electronics to store, manage and control the electrical energy. This includes the study of power electronics devices such as battery management systems, supercapacitors, and flywheels, which are used to store and manage electrical energy.

Overall, power electronics is a rapidly growing field with a wide range of applications in areas such as renewable energy, transportation, and industrial automation. It involves the use of electronic devices and control techniques to convert, control, and manage electrical power, and plays a critical role in the development of a sustainable energy future.