Power Electronics

Power electronics technology is still an emerging technology, and it has found its way into many applications, from renewable energy generation (i.e., wind power and solar power) to electrical vehicles (EVs), biomedical devices, and small appliances such as laptop chargers. In the near future, electrical energy will be provided and handled by power electronics and consumed through power electronics; this not only will intensify the role of power electronic technology in power conversion processes, but also implies that power systems are undergoing a paradigm shift, from centralized distribution to distributed generation. Today, more than 1000 gigawatts (GW) renewables (photovoltaic (PV) and wind) have been installed, all of which are handled by power electronics technology. However, areas such as energy-saving and electrification transportation are booming, creating a huge market not only for power devices but also for packaging technology and power converter design. Some of the driving forces of the technology are their cost, volume, weight, functionality as well as reliability. At the moment, the technology is seeing a change from being purely silicon-based to being built upon wide bandgaps (WBG) technology, such as silicon carbide (SiC) and gallium nitride (GaN), which demands a completely new paradigm in power converter design and layout, as those devices can operate at least an order of magnitude faster. The area of power electronics is so vast that an everyday average of 12 billion kilowatts per hour of power which is more than 80 % of the power generated is converted or processed or recycled by some of the power electronic devices.

We can define power electronics as a subject that is a hybrid of power engineering, analog electronics, semiconductor devices, and control systems. We derive the fundamentals of each subject and apply it in an amalgamated way so as to get a regulated form of electrical energy. Electrical energy in itself is not usable until it is converted into a tangible form of energy such as motion, light, sound, heat, etc. In order to regulate these forms of energy, an effective way is to regulate the electrical energy itself and this forms the content of the subject power electronics.

We can trace the overwhelming advancement in the subject back to the development of commercial thyristors or silicon-controlled rectifiers (SCR) by General Electric Co. in 1958. Before this, the control of electrical energy was mainly done using thyratrons and mercury arc rectifiers which work on the principle of physical phenomena in gases and vapors.

After SCR, a great many power electronic devices have emerged like GTO, IGBT, SIT, MCT, TRIAC, DIAC, IEGT, IGCT, and so on. These devices are rated for several hundreds of volts and ampere,s unlike the signal level devices which work at few volts and mill amperes.

In order to achieve the purpose of power electronics, the devices are made to work as nothing more than a switch. All the power electronic devices act as a switch and have two modes, i.e. ON and OFF

Majorly there are five types of power electronic circuits, each having a different purpose-

1. Rectifiers – converts fixed AC to variable DC (such as half-wave rectifiers or full-wave rectifiers)
2. Choppers – converts fixed DC to variable DC
3. Inverters – converts DC to AC having a variable amplitude and variable frequency
4. Voltage Regulators – converts fixed AC to variable AC at the same input frequency
5. Cycloconverters – converts fixed AC to AC with variable frequency

There is a common misconception about the term converter. The converter is basically any circuit that converts electrical power from one form to another. Above we have explored the five different types of converters.

It is literally impossible to list all the applications of power electronics today; it has penetrated almost all the fields where electrical energy is in the picture. This trend is an ever-increasing one especially with present trends of new devices and integrated design of power semiconductor devices and controllers. The ease of manufacturing has also led to the availability of these devices in a vast range of ratings and gradually has appeared in high voltage and extra-high voltage systems also. The day is not far when all of the electrical energy in the world will pass through power electronic systems.

Application of Power Electronics

Below is an attempt to briefly present the diaspora of power electronics.

Application of power electronics

• Our Daily Life: If we look around ourselves, we can find a whole lot of power electronics applications such as a fan regulator, light dimmer, air-conditioning, induction cooking, emergency lights, personal computers, vacuum cleaners, UPS (uninterrupted power system), battery charges, etc.
• Automotive and Traction: Subways, hybrid electric vehicles, trolleys, fork-lifts, and many more. A modern car itself has so many components where power electronic is used such as ignition switch, windshield wiper control, adaptive front lighting, interior lighting, electric power steering, and so on. Besides power electronics are extensively used in modern traction systems and ships.
• Industries: Almost all the motors employed in the industries are controlled by power electronic drives, for eg. Rolling mills, textile mills, cement mills, compressors, pumps, fans, blowers, elevators, rotary kilns, etc. Other applications include welding, arc furnace, cranes, heating applications, emergency power systems, construction machinery, excavators, etc.
• Defense and Aerospace: Power supplies in aircraft, satellites, space shuttles, advance control in missiles, unmanned vehicles, and other defense equipment.
• Renewable Energy: Generation systems such as solar, wind, etc. needs power conditioning systems, storage systems, and conversion systems in order to become usable. For example, solar cells generate DC power and for the general application, we need AC power and hence power electronic converter is used.
• Utility System: HVDC transmission, VAR compensation (SVC), static circuit breakers, generator excitation systems, FACTS, smart grids, etc.

Application of solid-state devices such as a diode, silicon-controlled rectifier (SCR), thyristors, gate turn-off thyristors, TRIAC, bipolar junction transistor (BJT), Power MOSFET, and so on for control and conversion of electric power is called as power electronics. The application of power electronics in automotive applications plays a major role in controlling automotive electronics. Automotive electronics include modern electric power steering, HEV main inverter, central body control, braking system, seat control, and so on.

Power Electronics Application in Electrical Engineering

Power Electronics is nothing but a way of converting electrical energy from one form to another, the output by the conversion is better, more efficient, error-free, clean, compact, simple, and convenient to use.

The area of power electronics is so vast that an everyday average of 12 billion kilowatts per hour of power which is more than 80 % of the power generated is converted or processed or recycled by some of the power electronic devices.

As power semiconductor devices improve in performance, efficiency and if the cost will be reduced, more systems will undoubtedly use power electronics.

Residential

• Refrigeration and freezers
• Space heating
• Air conditioning
• Cooking
• Lighting
• Electronics (PCs, other entertainment equipment

Commercial

• Heating, ventilating, and air conditioning
• Central refrigeration
• Lighting
• Computers and office equipment
• Uninterruptible power supplies (UPSs)
• Elevators
• Industrial
• Pumps
• Compressors
• Blowers and fans
• Machine tools (robots)
• Arc furnaces and induction furnaces
• Lighting
• Industrial lasers
• Induction heating
• Welding

Transportation

• Traction control of electric vehicles
• Battery chargers for electric vehicles
• Electric locomotives
• Streetcars, trolleybuses
• Subways
• Automotive electronics, including engine controls
• Utility systems
• HVDC
• SVC
• Supplemental energy sources (wind, photovoltaic), fuel cells
• Energy storage systems
• Induced draft fans and boiler feedwater pumps
• Aerospace
• Space shuttle power supply systems
• Satellite power systems
• Aircraft power systems
• Telecommunications
• Battery chargers
• Power supplies (DC and UPS)

It is literally impossible to list all the applications of power electronics today; it has covered almost all the areas where electrical energy is being used. This has become a trend now and it is increasing, especially with the present scenario of new devices and integrated design of power semiconductor devices and controllers. The ease of manufacturing has also helped these devices to be available so now a day these devices exist in a vast range of ratings and gradually have appeared in high voltage and extra-high voltage systems also. In the end, it can be summaries in the words that, the day is not far when all of the electrical energy in the world will pass through power electronic systems

Choosing the right Power electronics

Power electronics is one of the contemporary subjects of electrical engineering which has seen a lot of advancements in recent times and has impacted human life in almost every sphere. We over selves use numerous power electronic applications in our daily life, without also understanding t. Now the concern stands as, “what is power electronics?”

We can define power electronic devices as a subject that is a hybrid of power design, analog electronic devices, semiconductor devices, and also control systems. We obtain the fundamentals of each topic and also apply it in an amalgamated method so as to obtain a controlled form of electrical power. Electrical energy by itself is not usable till it is converted into a tangible kind of energy such as movement, light, audio, heat, etc. In order to manage these kinds of power, a reliable method is to control the electric power itself and this creates the content of the subject power electronics.

Gallon Electric can be your trusted supplier for power electronics components because of its best price & quality and we are also committed to ensuring better technical support for you.

We can trace the overwhelming advancement in the subject back to the development of commercial thyristors or silicon-controlled rectifiers (SCR) by General Electric Co. in 1958. Before this, the control of electrical energy was generally done making use of thyratrons and also mercury arc rectifiers which service the principle of physical phenomena in gases as well as vapors.

After SCR, an excellent numerous powerful electronic tools have emerged like GTO, IGBT, SIT, MCT, TRIAC, DIAC, IEGT, IGCT, and so on. These tools are rated for numerous hundreds of volts as well as ampere, unlike the signal level devices which at few volts as well as mill amperes. In order to accomplish the purpose of power electronic devices, the tools are made to work as nothing more than a switch. All the power electronic devices act as a button and also have 2 modes, i.e. ON and OFF

Gallon Electric can be the best choice for its ability to offer various types of powers electronics components like:

Power Diodes

A power diode is a type of diode that is commonly used in power electronics circuits. Just like a regular diode, a power diode has two-terminals and conducts current in one direction. A power diode varies in construction from a standard diode to enable this higher current rating.

In power electronic circuits, this diode plays an essential role. It can be used as a rectifier in converter circuits, voltage regulation circuits, flyback / freewheeling diode, reverse voltage protection, etc.

These diodes are related to signal diodes except for a slight disparity in their construction. The doping level in signal diode for both P-layer & N-layer is the same whereas, in power diodes, the junction can be formed among a heavily doped P+ layer & lightly doped N– layer.

Types of Power Diode

The classification of these diodes can be done based on the reverse recovery time, the process of manufacturing & the depletion region penetration in reversed bias condition.

The power diodes depending on the reverse recovery time as well as the process of manufacturing are classified into three types such as

• General Purpose Diodes
• Fast Recovery Diodes
• Schottky Diodes

How to Select?

The selection of power diode can be done based on the IF (forward current) & VRRM (the peak inverse) voltage.

These diodes are protected by using snubber circuits from the spikes of overvoltage. This may occur while doing the process of reverse recovery. A snubber circuit used for power diode mainly includes a resistor & a capacitor that is connected in parallel with the diode

Metal Oxide Semiconductor Field Effect Transistor (MOSFET)

Power MOSFET is a type of MOSFET which is specially meant to handle high levels of power. These exhibit high switching speed and can work much better in comparison with other normal MOSFETs in the case of low voltage levels. However, its operating principle is similar to that of any other general MOSFET. Power MOSFETs that are most widely used are n-channel Enhancement-mode or p-channel Enhancement-mode or n-channel depletion-mode in nature

There are a wide variety of power MOSFET structures like Vertical Diffused MOS (VDMOS) or Double-Diffused MOS or DMOS, UMOS or Trench-MOS, VMOS, etc

Although the structures of the normal MOSFETs and the power MOSFETs are seen to be different, the basic principle behind their work remains unaltered. That is, in both of them the formation of the conduction channel is the same which is nothing but the suitable bias applied at the gate terminal resulting in an inversion layer.

Power Bipolar Junction Transistor (BJT)

The power bipolar junction transistor (BJT) blocks a high voltage in the off state and high current carrying capacity in the on-state. The power handling capacity is very high.

• Application of Power BJT:
• Switched Mode Power Supply (SMPS)
• Power Amplifier
• Relay and Drivers
• AC motor speed controller
• DC/AC inverter
• As series pass transistor in the regulated power supply
• The audio amplifier in the stereo system
• Power control circuit

Power BJT is used traditionally for many applications. However, IGBT (Insulated-Gate Bipolar Transistor) and MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) have replaced it for most of the applications but still, they are used in some areas due to their lower saturation voltage over the operating temperature range. IGBT and MOSFET have higher input capacitance as compared to BJT. Thus, in the case of IGBT and MOSFET, the drive circuit must be capable to charge and discharge the internal capacitances.

Insulated-Gate Bipolar Transistor (IGBT)

IGBT combines the physics of both BJT and power MOSFET to gain the advantages of both worlds. It is controlled by the gate voltage. It has a high input impedance like a power MOSFET and also has low on-state power loss as in the case of BJT. There is no even additional breakdown and also not have long switching time as in the case of BJT. It has much better conduction characteristics as contrasted to MOSFET as a result of its bipolar nature. It has no body diode as in the case of MOSFET but this can be viewed as an advantage to using an external fast recovery diode for specific applications. They are changing the MOSFET for a lot of the high voltage applications with much fewer conduction losses.

Thyristors (SCR, GTO, MCT)

Thyristors are the family of solid-state devices extensively used in power electronics circuitry such as SCR (silicon-controlled rectifier), DIAC (diode on AC), TRIAC (the triode on AC), GTO (gate turn-off thyristors), MCT (MOS-controlled thyristor), RCT, PUT, UJT, LASCR, LASCS, SIT, SITh, SIS, SBS, SUS, SBS and etc. SCR is the oldest member and the head of this family; and usually referred to with the name “thyristor”.

They are operated as bistable switches that are either working in the non-conducting or conducting state. Traditional thyristors are designed without gate-controlled turn-off capability in which the thyristor can come from conducting state to non-conducting state when only anode current falls below the holding current. While GTO is a type of thyristor that has a gate-controlled turn-off capability.

SCR

SCR usually has three terminals and four layers of alternating p and n-type materials. The structure of the thyristor can be split into two sections: NPN and PNP transistors for simple analysis purposes. It has three terminals named  cathode, anode, and gate

GTO (Gate Turn-off Thyristor)

GTO can be turned on with the positive gate current pulse and turned off with the negative gate current pulse.Its capability to turn off is due to the diversion of PNP collector current by the gate and thus breaking the regenerative feedback effect.

Actually, the layout of GTO is made as though the PNP present gain of GTO is lowered. Highly doped n places in the anode player develop a shorted emitter effect and also ultimately lowers the current gain of GTO for reduced current regeneration and additionally the reverse voltage obstructing ability. This reduction backward obstructing capacity can be enhanced by diffusing gold however this minimizes the carrier lifetime.

MCT (MOS-Controlled Thyristor)

Out of many semiconductor-controlled devices, MCT is considered to be the latest. The device is basically a thyristor with two MOSFETs built into the gate structure. A MOSFET is used for turning ON the MCT and another one is used for turning it OFF. The device is mostly used for switching applications and has other characteristics like high frequency, high power, and low conduction drop, and so on. An MCT combines the feature of both conventional four-layer thyristor having regenerative action and MOS- gate structure. In this device, all the gate signals are applied with respect to the anode, which is kept as the reference. In a normally used SCR, the cathode is kept as the reference terminal for gate signals.

Advantages of MCT

• Low forward conduction drop
• Fast TURN-ON and then OFF times
• Low switching losses
• High gate input impedance

What to expect from Gallon Electric?

With all the risk awaiting you when purchasing Power Electronics components globally, you definitely want to contract with a genuine and a trusted wholesaler that will help you place orders and see your order delivered. That is exactly what Gallon Electric offers you.

Why Gallon Electric?

Power Electronics are very vital for any industrial and power-related company types of machinery. If you are looking for those Power Electronics components Gallon Electric might be your best choice.

Gallon Electric can be your trusted supplier for Power Electronics components because of its best price & quality and we are also committed to ensuring better technical support for you.

Gallon Electric is committed to providing customers with authorized genuine components with the least risk of counterfeit. We can provide full traceability on the commercial components sold. From sales to shipping Gallon Electric is committed to meeting your requirements for the right product, on time

Gallon Electric can be your trusted supplier for buying power electronics related devices and components because of its best price & quality and we are also committed to ensuring better technical support for you. Gallon Electric commits to quality products, high service, and timely delivery to our customers.