The History of Power Electronics

Introduction

Power electronics or Power engineering can be considered as an underestimated field of engineering, and thus may not be as popular as other forms like VLSI, Embedded but in reality it is not. It also has a great importance in the world since its beginning.

For systems or devices which work on more than one phase, Power Electronics plays an important role there. Power Electronics comprises components which work in  conversion, control, and conditioning of electric power. They manipulate the primary characteristics of electric power like conversion from AC to DC or vice versa, altering voltage and current levels, changing the operating frequency or power factor according to the needs. 

Power Electronics helps in regulating the nonelectrical parameters like the intensity of lighting, the speed of a motor, the rate of an electrochemical process, or the temperature of an oven. Its applications can be found everywhere and have significant impact on global industry. 

In the 21st Century, growth of many different technologies was seen. And with this growth manipulation and conversion of energy sources gained utmost importance. Here, it gave rise to the Power Electronics, which helped humans to use Electricity efficiently.

Power engineering has its impact in many sectors such as residential, industrial, commercial, medical, communications, transportation, aerospace, and military.

The History of Power Electronics

In the initial years when Electronics was just getting popular, the early 1900’s, the emergence of Power Electronics can be said when Peter Cooper Hewitt (an electrical engineer)  in 1902 invented the mercury arc rectifier. The first rectifier which was able to convert AC to DC power without any mechanical aid.

Fig. 1: Peter Cooper Hewitt and the first rectifier

    

    Next great invention we had was the triode (first ever practical amplifier) by Lee De Forest in 1906.

    

Fig. 2: Lee De Forest

    

Many more inventions like Errol Shand’s metal tank rectifier came along, then Joseph Salopian’s ignitron in the 1930s. These all innovations which happened mainly focused on energy control. The main breakthrough came in 1948, some may say it was a revolution in the field of Power Electronics, it was the invention of Silicon Controlled Rectifier at Bell Laboratories. This led to the formation of different devices like thyristors and UJTs, etc.

Fig. 3: Invention of Silicon Controlled Rectifier at Bell Laboratories

Modern Day Power semiconductor devices include bipolar junction transistor (BJT), metal-oxide-field effect transistor (MOSFET),  gate turn-off switch (GTO), SCRs, Thyristors, MOS Controlled Thyristor (MCT) and insulated-gate bipolar junction transistor (IGBT) which is a hybrid device made from BJT and MOSFET.