Electric machines and apparatus

 

 

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In electrical engineering, electric machine is a general term for machines using electromagnetic forces, such as electric motors, electric generators, and others. They are electromechanical energy converters: an electric motor converts electricity to mechanical power while an electric generator converts mechanical power to electricity.

 

The moving parts in a machine can be rotating (rotating machines) or linear (linear machines). Besides motors and generators, a third category often included is transformers, which although they do not have any moving parts are also energy converters, changing the voltage level of an alternating current.

 

An electric generator is an electrical machine which converts mechanical energy into electrical energy. A generator works on the principle of electromagnetic induction. It states that whenever a conductor moves in a magnetic field, an emf gets induced within the conductor. This phenomenon is called as generator action.

 

Faraday’s laws of electromagnetic induction explains the relationship between electric circuit and magnetic field. This law is the basic working principle of the most of the electrical motors, generators, transformers, inductors etc.

 

A motor is an electrical machine which converts electrical energy into mechanical energy. When a current carrying conductor is placed in a magnetic field, the conductor experiences a mechanical force and this is the principle behind motoring action.

 

Transformers do not actually make conversion between mechanical and electrical energy, but they transfer electric power from one circuit to another circuit. They can increase or decrease (step-up or step-down) the voltage while transferring the power without changing the frequency.

 

Input power and output power of an electrical transformer should ideally be the same. Step up transformers increases the voltage level from primary to secondary but with the corresponding decrease in the current.

 

 

 

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Electrical complexes and systems

 

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Electrical systems are groups of electrical components connected to carry out some operation. Often the systems are combined with other systems. They might be subsystems of larger systems and have subsystems of their own.

 

An electrical network is an interconnection of electrical components (e.g. batteries, resistors, inductors, capacitors, switches) or a model of such an interconnection, consisting of electrical elements (e.g. voltage sources, current sources, resistances, inductances, capacitances).

 

An electrical circuit is a network consisting of a closed loop, giving a return path for the current.

 

Linear electrical networks, a special type consisting only of sources (voltage or current), linear lumped elements (resistors, capacitors, inductors), and linear distributed elements (transmission lines), have the property that signals are linearly superimposable.

 

An electric power system is a network of electrical components deployed to supply, transfer, store, and use electric power. An example of an electric power system is the grid that provides power to an extended area.

 

An electrical grid power system can be broadly divided into the generators that supply the power, the transmission system that carries the power from the generating centres to the load centres, and the distribution system that feeds the power to nearby homes and industries.

 

Using transducers, physical properties such as temperature, pressure, flow, force, and many others can be converted into electrical signals, which can then be conveniently measured and recorded.

 

 

 

 

 

 

 

 

 

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Power Electronics

 

 

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Power electronics is the application of solid-state electronics to the control and conversion of electric power.In contrast to electronic systems concerned with transmission and processing of signals and data.

 

Solid-state electronics means semiconductor electronics; electronic equipment using semiconductor devices such as semiconductor diodes, transistors, and integrated circuits (ICs).

 

The term is used for devices in which semiconductor electronics which have no moving parts replace devices with moving parts, such as the solid-state relay in which transistor switches are used in place of a moving-arm electromechanical relay, or the solid state disk (SSD) a type of semiconductor memory used in computers to replace hard disk drives, which store data on a rotating disk.

 

Today almost all electronics is solid state, except in some applications such as radio transmitters in which vacuum tubes are still used, and some power industrial control circuits which use electromechanical devices such as relays.

 

Additional examples of solid state electronic devices are the microprocessor chip, LED lamp, solar cell, charge coupled device (CCD) image sensor used in cameras, and semiconductor laser.

 

As the trend towards electrification and renewable energies increases, enabling technologies such as power electronics are becoming ever more important.

 

Power electronics is an umbrella term that encompasses the systems and products involved in converting and controlling the flow of electrical energy.

 

 

 

 

 

 

 

 

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Electrical engineering and electrophysics

 

 

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Electrophysics represents the overlap between physics and electrical and computer engineering, and the products of Electrophysics ultimately fit into other areas of electrical and computer engineering such as: communications and signal processing, computer engineering, microelectronics, and controls.

 

Electrophysics is an essential component to bring concepts grounded in the principles of physics together with systems engineering to create complex systems that work in real life. Devices that emerge from Electro physics are embedded in almost all modern electronics.

 

Electrophysics education and research deals with optics, lasers, detectors, microwaves, particle beams, nanotechnology, magnetics, and electromagnetic phenomena at all wavelengths, from x-rays, to radio waves.

 

The Master of Science program in Electrophysics prepares students to work at the interface between electrical engineering and physics, where new engineering applications of various physical phenomena are developed. Emphasis is on wave propagation, microwave circuits, electroptics and plasmas.

 

An electrical engineer is someone who designs and develops new electrical equipment, solves problems and tests equipment. They work with all kinds of electronic devices, from the smallest pocket devices to large supercomputers. Electrical engineering deals with electricity, electro-magnetism and electronics.

 

Electrical engineering has now subdivided into a wide range of subfields including electronics, digital computers, computer engineering, power engineering, telecommunications, control systems, robotics, cybersecurity, radio-frequency engineering, signal processing, instrumentation, and microelectronics.

 

From the Global Positioning System to electric power generation, electrical engineers have contributed to the development of a wide range of technologies. They design, develop, test, and supervise the deployment of electrical systems and electronic devices.

 

 

 

 

 

 

 

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