Power electronics is one of those technologies that is embedded in everything (we use almost every day) without being noticed. Power electronics is behind all of your household electronics, renewable energy systems, EVs, and even industrial equipment.

Power electronics helps create smart and efficient systems and energy controls in various applications on a device, machine, system, or equipment level.

As industries begin to shift towards decreasing operating costs while improving system performance and workplace conditions, thermal acoustic insulation would help meet those needs. In fact, GMI Research predicts the Power Electronics Market will exceed USD 66.2 billion in 2030.

What Is Power Electronics?

Power electronics combines the principles of electrical engineering with semiconductor devices, and is used to manipulate and optimize the flow of electric power from a source to a load in a reliable, compact, and efficient manner.

There are differences between the fields of general and power electronics. Traditional or general electronics deal with relatively low power signals. On the other hand, power electronics deal with much higher power levels.

Three major concepts form the foundation of power electronics: solid state, conversion and control.

Solid state power consists of semiconductor devices used to switch and control energy in the form of electric power. Power conversion relates to the transformation of one form of electric power to other forms (i.e. AC to DC, DC to AC, etc.) or to variations of voltage and/or current. Control systems regulate the output to meet the application's requirements.

The combination of the three major concepts of power electronics allows for a wide variety of applications.

How has Power Electronics Advanced?

The development of power electronics can be traced back to the early 1900's. Early systems used rectifiers of low complexity to convert AC to DC. The Walther Edwin Horn, who worked at AT&T, invented the first DC rectifier diode using a vacuum tube to control a DC current. His work was later improved on by others, who replaced the Selinium-based devices with diodes.

In 1950, the development of the thyristor, a silicon-controlled switch, pioneered the field of modern-day power electronic controls and conversion.

The development of power MOSFETs and IGTs during the 1970s and 1980s drastically increased the field of power electronics. Power MOSFETs, IGBTs, and other devices of similar function made power electronic systems smaller and more user friendly because of decreased size, improved switching, efficiency, and enhanced power capacity.

The development of variable frequency drives (VFDs) had a great deal of impact on industry. Using VFDs, industrial energy consumption could be slashed while permitting control of motor speeds and torque.

Another shift occurred in the 1990s as digital technology progressed. Specifically, the advent of microcontrollers and DSPs (digital signal processors) provided engineers with tools to make increasingly precise control systems of great adaptability.

Today, the power electronics industry is beginning to move well beyond silicon. New semiconductor materials based on wide-bandgap semiconductors, such as silicon carbide (SiC) and gallium nitride (GaN), enable increased efficiency, power density, operating temperatures, and voltages. These enable further innovations in electric vehicles, as well as other advanced systems in industry, energy, and electronics.

What Are the Key Components of Power Electronics?

Each has a role to play in a power electronic system. Controlling and adjusting the output is done with controllers and regulators, while converters effect the transformation of energy. Semiconductors perform the switching and control of current flow.

What Role Do Semiconductors Play?

Semiconductors are the fundamental subsystems of power electronics. Amongst others, power systems use diodes, transistors, and integrated circuits.

Rectifying current flow in one direction is done with diodes. While silicon and germanium are used to make power diodes, high voltage diode systems may use silicon carbide or gallium nitride.

SiC-based diodes are effective at higher voltages and temperatures.

Transistors function as either switches or amplifier devices in power electronic circuits. Examples include BJTs, FETs, MOSFETs, and IGBTs.

In power electronic circuits, MOSFETs are good choices for low to medium power and fast switching applications. IGBTs also can switch fast, but can handle the power levels associated with higher power applications.

What Are Power Electronic Converters?

Power converters transform electrical power from one form to another. The type of converter needed varies based on the specific application.

AC-to-DC Converters

AC-to-DC converters, or rectifiers, change the form of alternating current to direct current. Rectifiers range widely from simple single-phase diode bridges to complex three-phase controlled rectifiers.

Applications of this type of conversion include battery chargers and DC motor drives.

DC-to-AC Converters

Inverters are DC-to-AC converters. The opposite of rectification is performed by an inverter, which changes direct current to alternating current.

These converters are utilized in the power systems of electric vehicles, as well as additional power systems, like solar power systems. Modern designs are capable of controlling the voltage and frequency of the output in order to fulfill the requirements of the grid, or the requirements of a particular load.

Why Are Controllers and Regulators Important?

The conversion of power is only one of many functions a complete system must perform. The output of a given system must be kept constant and controlled.

Controllers

The operation of converters and inverters are dictated by controllers. The operation of a controller is to adjust the output in order to meet the defined requirements of the system.

A controller can be a very basic analog circuit or a complex digital system that uses a microprocessor or a digital signal processor, depending on the application.

This specific kind of control is necessary in applications where torque and speed are needed to be controlled, such as in motor drives.

Regulators

Regulators focus on controlling the output voltage or current in case the input voltage or the load changes, respectively.

For this reason, they can be used in power supply units or battery chargers in which variation of input voltage/current can damage sensitive electrical components and also affect the system as a whole.

A reliable regulator helps to keep the output of the power electronic system stable and therefore helps the system to function safely.