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EEE 338POWER ELECTRONICS

INTRODUCTION TO POWER ELECTRONICS

Dr. Shahab Ahmad Niazi

POWER ELECTRONICS1. Mohan, Ned, Tore Undeland, and William Robbins. Power Electronics: Converters, Applications, and Design. 2nd ed.

2. Rashid, Muhammad H. Power Electronics and Electric Power. 2nd ed.

3. Kassakian, John G., Martin F. Schlecht, and George C. Verghese. Principles of Power Electronics.

EEE338-Syllabus

Introduction of Power Electronics, Solid State Devices for Power Electronics, Power Diodes, Power BJTs, Power MOSFETs, IGBT, SCR’s, GTO, & TRIAC and DIAC, SCR Firing & Commutation Techniques, Thyristors Characteristics, Construction, Operations & Applications, Thyristors Commutation, Half Wave and Full Wave Rectifiers, Un-controlled & Controlled Rectifiers. 3 Phase, 6-Pulse, 12-Pulse and 24 Pulse Rectifiers, AC Voltage Controllers, DC to AC Converters, Single Phase DC to AC Converters, Invertors, Half Bridge & Full Bridge Invertors, 3 Phase, 6-pulse & 12 Pulse Inverters, DC to DC Converters, Design & Analysis of Regulated Power Supplies, Switch Mode Power Supplies, Uninterrupted Power Supplies.

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Course Description

Examines the application of electronics to energy conversion and control. Topics covered include: Modelling, analysis, and control techniques; design of power circuits including inverters, rectifiers, and DC-DC converters; and characteristics of power semiconductor devices. Numerous application examples will be presented such as motion control systems, power supplies, and radio-frequency power amplifiers.

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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

The interdisciplinary nature

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

POWER ELECTRONICS TECHNOLOGY

As the technology for the power semiconductor devices and integrated

circuit develops, the potential for applications of power electronics become

wider. The power semiconductor devices or power electronic converter fall

generally into four categories :

AC to DC Converter (Controlled Rectifier)DC to DC Converter (DC Chopper)AC to AC Converter (AC voltage regulator)DC to AC Converter (Inverter)

The design of power electronics converter circuits requires design the

power and control circuits. The voltage and current harmonics that are generated by the power converters can be reduced or minimized with a proper choice of the control strategy.

Power Electronics Application

Power Electronics defined as the application of solid-state (devices) electronics for the control and conversion of electric power.

Power electronics have already found an important place in modern technology and are now used in a great variety of high-power product, including heat controls, light controls, electric motor control, power supplies, vehicle propulsion system and high voltage direct current (HVDC) systems.

1.Uncontrolled turn on and off (Power Diode)

2.Controlled turn on uncontrolled turn off (Thyristors)

3.Controlled turn on and off characteristic (Power Transistor, BJT,

MOSFET, GTO, IGBT)

4.Continuous gate signal requirement (BJT, MOSFET, IGBT)

5.Pulse gate requirement (SCR(Silicon-Controlled Rectifier) , GTO)

6.Bidirectional current capability (TRIAC)

7.Undirectionalcurrent capability (SCR, GTO, BJT, MOSFET,

IGBT)

POWER ELECTRONIC SWITCHING DEVICES

The history

Mercury arc rectifier Vacuum- tube rectifier

Thyratron

Invention of Thyristor

Applicat ion of fast- switching fully- controlled semiconductor

devices

Power diode Thyristor

GTO GTR

Power MOSFET Thyristor

(microprocessor)

IGBT Power MOSFET

Thyristor (DSP)

Pre-history

1st phase

2nd phase

3rd phase

1957

1900

late 1980s

mid 1970s

Diagram Block of Converters

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 )

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Control Center

Micro-Turbine Hospital Commercial

Building

Fuel Cell Smart House Performance

Building

Combined Heat and PowerPlant (CHP)FactoryCommercial BuildingHouseApartment Building

Wind Power Plants Village Commercial

Building

Central PowerStation Solar Power Plants

CHP House

ImportanceIncreasing applications of Power Electronic Equipment in Power SystemsAvailability of high power semiconductor devicesDecentralized renewable energy generation sourcesIncreased power transfer with existing transmissionsystemEffective control of power flow needed in a deregulated environmentNorms for Power quality

Future Power System

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Listing of Power Electronic Applications

Distributed generation (DG) Renewable resources (wind and photovoltaic) Fuel cells and micro-turbines Storage: batteries, super-conducting magnetic energy storage,

flywheels Power electronics loads: Adjustable speed drives

Power quality solutions Dual feeders Uninterruptible power supplies Dynamic voltage restorers

Transmission and distribution (T&D) High voltage dc (HVDC) and medium voltage dc Flexible AC Transmission Systems (FACTS): Shunt and Series

compensation, and the unified power flow controller

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Role of Power Electronics in Important Utility Applications

Power Electronic Loads: Adjustable Speed Drives

Controller

Motor

Utility

Rectifier

Switch-modeConverter

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Role of Power Electronics in Important Utility Applications

• Transmission and Distribution: Flexible AC Transmission Systems (FACTS)

1 2 sinE E

PX

1E

2E

3E

+- 3E1E 2E

Shuntconverter

Seriesconverter

I

Shunt and Series Compensation

Series Compensation

Applications

Industrial applications Motor drives Electrolysis Electroplating Induction heating Welding Arc furnaces and ovens Lighting

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• hybrid cars, in which the primary electrical system is dominated by power electronics. Electric cars offer high performance, zero tailpipe emissions, and low costs, but are still limited in range by the need for batteries.

• Hybrid car designs use various strategies to combine both an engine and electrical elements to gain advantages of each.

• Inverters and DC-DC converters rated for many kilowatts serve as primary energy control blocks.

Hybrid Cars

Transportation applications

Trains & locomotives

Subways

Trolley buses

Magnetic levitation

Electric vehicles

Automotive electronics

Ship power systems

Aircraft power systems

Applications in space technology

Spaceship power systems Satellite power systems Space vehicle power systems

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

Heat Removal Mechanism

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SCR (stud-type) on air-cooled kits

Fin-type Heat Sink SCR (hokey-puck-type) on power pakkits

Assembly of power converters

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Ratings of Power Devices

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Summary

The characteristics of the power devices play a major role in the speed and effectiveness of the power conversion.

Power electronics uses low power electronics (ICs), control, and switching power devices for power converter and/or processing from one form to another.