| Unit name | Power Electronic Systems |
|---|---|
| Unit code | EENGM7011 |
| Credit points | 10 |
| Level of study | M/7 |
| Teaching block(s) |
Teaching Block 2 (weeks 13 - 24) |
| Unit director | Professor. Stark |
| Open unit status | Not open |
| Pre-requisites | |
| Co-requisites |
None. |
| School/department | School of Electrical, Electronic and Mechanical Engineering |
| Faculty | Faculty of Engineering |
This unit covers the operation of power electronic circuits set into the context of actuation and renewable energy generation. The fundamental converter topologies are covered first as a means to understanding more complex 3-phase inverters. Inverter operation is studied in examples and by computer simulation. Finally, their integration into larger systems is discussed, for example where inverters tie renewable energy generation to electrical networks. Power quality, network stability, influence of parasitics and layout, and energy efficiency are topics throughout.
Elements
Power Semiconductor Devices and their Applications Dr B.H. Stark
Minority carrier devices:
The power diode, the PIN diode, minority carrier lifetime control, the Bipolar Junction Transistor.
Conduction losses in power devices, switching losses in power devices, device losses with resistive load, device losses with clamped inductive load.
SOA and use of snubbers
Power Darlingtons
Driving methods for BJTs
The phase controlled thyristor – Inventor Grade thyristor
The GTO, snubber design for GTOs, gate circuits for GTOs.
The CGT
The triac
Majority carrier devices:
The power MOSFET, gate drive circuits for power MOSFETs
The IGBT and gate drivers
Short circuit capability of power devices, avalanche capability of power devices.
The Schottky diode and its applications
Super-junction devices Comparison of device characteristics
Comparison of device applications
Inverters and AC Variable-Speed Drives Dr B.H. Stark
Basic principles of the induction motor.
Equivalent circuit.
Constant V/f operation.
Slip, slip speed, slip frequency and torque.
Fan load and constant torque load.
Constant power operation.
Vector control. Slip control.
Braking and generating.
PWM inverters.
Harmonic losses.
Iinverter commutation
Inverter conduction losses
Elimination of harmonics in PWM waveforms.
Regular and natural sampled PWM
Ratio changing.
Torque and speed control loops.
Over-voltage transients due to transmission line effects and poor voltage sharing in windings
Enclosure standards for motors.
Power quality and EMC standards for drives
You will be able to select circuit topologies for different power applications, and contrast these power electronic circuits by their operation, control requirements, and the environment in which their power semiconductor devices operate. You will be able to support the design process through analysis of the operation, and in the case of complex topologies, through simulation using Matlab/Simulink. You will be able to recommend various levels of abstraction for the design process, from analysing simple circuits with real switching, through more complex topologies where switches are considered ideal, to system integration, where converters are considered ideal (non-switching). Whilst some of the lecture will provide conceptualised theory, you will embed this learning in most lectures by means of short examples on aspects of circuit design, deriving operating points, sketching output waveforms, etc. Discussion and debate will be encouraged.
Combination of lectures and laboratory sessions
Name: Terminal Exam
Type: Exam
% of final mark: 100
Description: 2 hour written paper
Mohan, N., Undeland, T., & Robbins, W., Power Electronics: Converters, Application and Design, John Wiley & Sons, ISBN 0471226939
