Power Electronics

College of BVC institute of Science and Technology

Introduction

Outline What is power electronics? The history Applications About this course

I. What is power electronics?

1) Definition

Power Electronics: is the electronics applied to conversion and

control of electric power.

Range of power scale :

milliwatts(mW) megawatts(MW) gigawatts(GW)

A more exact explanation:

The primary task of power electronics is to process and control the

flow of electric energy by supplying voltages and currents in a

form that is optimally suited for user loads.

Conversion of electric power

Other names for electric

power converter:

-Power converter

-Converter

-Switching converter

-Power electronic circuit

-Power electronic converter

Electric Power Converter

Power output

Power input

Control input

Power electronic system

Generic structure of a power electronic system

Control is invariably required.Power converter along with its controller

including the corresponding measurement and interface circuits, is

also called power electronic system.

Power Converter

Control input Controller

Reference

Power input

Power output

Feedback (measurements of output signals )

Feedforward ( measurements of input signals )

A typical power electronic system

The task of power electronics has been recently extended to also ensuring the currents and power consumed by power converters and loads to meet the requirement of electric

energy sources.

Power Converter

Measurements

Controller Reference

Power input

Power output

Electric Motor light heating other electric equipment power converter

Electric utility battery other electric energy source power converter

Source

Load

io

Vo

ii

Vi

2) Relation with information electronics

A Classification of electronics by processing object

Other classifications of electronics

Electronics

Information electronics: to process information Power electronics: to process electric power

Electronics

Vacuum electronics: using vacuum devices, e.g, vacuum tubes devices

Solid (Solid state) electronics: using solid state devices,

e.g, semiconductor devices

Electronics

Physical electronics: physics,material,fabrication, and manufacturing of electronic devices

Applied electronics: application of electronic

devices to various areas

3) The interdisciplinary natureWilliam E. Newell’s description

Power electronics is the interface between electronics and power.

Power Electronics

学

Electronics

Power

学

Control

Continuous,

discrete

连续、离

散

Static & rotating

power equipment

Devices,circuits

Relation with multiple disciplines

Power electronics is currently the most active discipline in electric power engineering.

Power electronics

electronics electr

Electric machines

Circuit Ct theory

Systems& Control theory

Control

theory

Signal processing

Simulation & computing

electronics

Solid state

physics

Electromagnetics

Power systems

4) Position and significance in the human society

Electric power is used in almost every part and everywhere of modern

human society.

Electric power is the major form of energy source used in modern

human society.

The objective of power electronics is right on how to use electric power,

and how to use it effectively and efficiently, and how to improve the

quality and utilization of electric power.

Power electronics and information electronics make two poles of

modern technology and human society: information electronics is the

brain, and power electronics is the muscle.

III. Applications

Industrial applications

Motor drives

Electrolysis

Electroplating

Induction heating

Welding

Arc furnaces and ovens

Lighting

Transportation applications Trains & locomotives Subways Trolley buses Magnetic levitation Electric vehicles Automotive electronics Ship power systems Aircraft power systems

Utility stems applications High- voltage dc transmission(HVDC)Flexible ac transmission(FACTS)Static var compensation & harmonicssuppression: TCR, TSC, SVG, APFCustom power & power quality controlSupplemental energy sources :wind, photovoltaic, fuel cellsEnergy storage systems

Telecommunication Applications

Battery charges Power supplies SMPS UPS Cell phone

charges

Power supplies for electronic equipment

Computers

Office equipment

Electronic instruments

Portable or mobile

electronics

Residential and home appliances

Lighting

Heating

Air conditioning

Refrigeration & freezers

Cooking

Cleaning

Entertaining

Applications in space technology

Spaceship power systems

Satellite power systems

Space vehicle power systems

Other applications

Nuclear reactor control

Power systems for particle accelerators

Environmental engineering

TYPES OF LED’S APPLICATIONS OF LED’S

PHOTOGRAPHY WITH LED’S

Because LEDs are cheap. Having a ton of LEDs allows you to position a huge amount of light sources on any miniature detail oriented given setup that the setup is small enough.

LED’S WIYH SHOES

Since LEDs are so small and so focused you can have full control on where you want light and where you want dark. In the image to the left (click for more info) I used a restricted LED light to throw light on the edges and white portions of the shoe.

LED’S ARE EASY TO DESIGN

THE 1$ RING LIGHT

Trends It is estimated that in developed countries now 60% of the electric

energy goes through some kind of power electronics converters before it is finally used.

Power electronics has been making major contributions to: --better performance of power supplies and better control of electric

equipment --energy saving --environment protection reduction of energy consumption leads to less pollution reduction of pollution produced by power converters direct applications to environment protection technology

IV. A simple example

A simple dc-dc converter example

Input source:100VOutput load:50V, 10A, 500WHow can this converter be realized?

Dc-dc converter

+ -

+

-

V

50V

R

5Ω

I

10A

Vg

100V

Major issues in power electronicsHow to meet the requirement of the load or gain better control of the loadHow to improve the efficiency -- for reliable operation of power semiconductor devices -- for energy savingHow to realize power conversion with less volume, less weight, and less

cost.How to reduce negative influence to other equipment in the electric power

system and to the electromagnetic environment.

Thank you For giving this opportunity

.

QUERIES????.....