AE26  POWER ELECTRONICS

 

1.         Thyristor and other Power Semiconductor Devices                                      8 hours

 

1.1         Devices belonging to the thyristor  family: Thyristor,  Triac, GTO thyristor, MOS-controlled thyristor, Static Induction Thyristor.

1.2         Two-transistor model of a Thyristor, Thyristor Characteristics, Gating Requirements, Thyristor Firing Circuits and their Control Features, UJT, PUT.

1.3         Thyristor turn-on and turn-off Mechanisms, Ratings, Losses and Cooling.

1.4         Series and Parallel operation of Thyristors, Overcurrent and Overvoltage Protection;  di/dt and  dv/dt Protection.

1.5         Other Power Electronic Devices: Power transistor, Power MOSFET, IGBT.

 

I [1 (1.2-1.11), 10 (10.1, 10.2)]; II [4(4.2-4.13)]

 

2.         Controlled Rectifier Circuits and Converter operation                                8 hours

 

2.1     Single-phase Half-wave, Bi-phase Half-wave and Single-phase Bridge (or full-wave) configurations.

2.2     Three-phase Half-wave, Six-phase Half-wave and Three phase Bridge (or full wave)  Configurations, twelve-pulse circuits.

2.3     Transformer Ratings for Rectifying circuits.

2.4     Inverting mode of a Converter, Regulation.

2.5         Three-phase Dual converters; Power Factor Improvement techniques: Extinction angle control, Symmetrical angle control, Pulse Width Modulation (PWM), Sinusoidal PWM.

2.6         Design of converter circuits, effect of load and source impedances (overlap), Gating Circuits.

 

            I [2 (2.1-2.11), 3 (3.1-3.4)], II [5(5.1-5.4)]

 

3.         D C Choppers                                                                                                8 hours

 

3.1         Principles of Step-down Choppers and their operation with RL load, Step-up choppers.

3.2         Chopper classification, class A, B, C, D and E Choppers.

3.3         Switching mode Regulators: Buck, Boost, Buck-boost and Cu’k Regulators.

3.4         Thyristor Chopper circuits: Impulse-commutated choppers, Effects of source and load inductance, Resonant Pulse Choppers.

3.5         Chopper circuit design.    

        

II [9 (9.1-9.9)]

 

4.         Thyristor Commutation Techniques                                                              6 hours

 

 4.1    Natural commutation techniques.

 4.2    Forced-commutation techniques: Self, Impulse, Resonant pulse, Complementary, External pulse, Load side and Line side Commutation circuits.

 4.3    Commutation circuit design.

 

 II [7 (7.1-7.4)]

 

5.         A C Voltage Controllers                                                                                8 hours           

 

5.1         On-off and Phase control principles.

5.2         Single-phase AC controllers with Resistive and Inductive loads.

5.3         Three-phase AC controllers: Half-wave, Full-wave and Bidirectional delta connection configurations.

5.4         Single-phase Transformer-tap changers.

5.5         Design of AC Voltage-controller circuits.

5.6         Effects of Source and Load Inductances.

 

II [6 (6.1-6.9, 6.11-6.13)]

 

6.         Cycloconverters                                                                                             8 hours

 

    6.1    Principle of a Single-phase Cycloconverter.

    6.2    Blocked Group Operation.

    6.3    Circulating current mode.

    6.4    Control of a cycloconverter.

    6.5    Three-phase cycloconverters, Reduction of output harmonics.

 

            I [5 (5.1)]; II [6 (6.10)]

 

7.         Inverter Circuits                                                                                            8 hours

 

 7.1    Single-phase Center-tapped Inverter.

 7.2    Single-phase Half-bridge and bridge configurations.

 7.3    Three-phase Inverters: 180-degree and 120-degree conduction.      

 7.4    Voltage control of Single-phase Inverters: Single PWM, Multiple PWM and Sinusoidal  PWM.

 7.5    Voltage control of Three-phase Inverters.

 

            I [5 (5.3)]; II [10 (10.1-10.7)]

 

8.         D C and A C Drives                                                                                       6 hours

 

  8.1   Basic Characteristics and Operating modes of D C Motors.

  8.2   Single-phase and three-phase Converter Drives.

  8.3   Chopper Drives, principles of Regenerative Braking and Rheostatic Braking controls.

  8.4   Induction Motor Drives and their Performance Characteristics.

  8.5   Speed and Torque variation using the various controls: Stator voltage,

         Rotor-voltage, Frequency and Stator Current controls.

8.6     Industrial Applications of DC and AC Drives.

8.7     Microprocessors in the control of Electrical Drives.

 

            I [8 (8.6), 9(9.12)]; II [14 (14.1-14.6), 15 (15.1-15.2)]; III [7 (7.1-7.6)]

           

 

Text Books

 

I.          Cyril W Lander, “Power Electronics”, McGraw Hill Book company, Singapore (1993).

II.        Muhammad  H Rashid, “Power Electronics-Circuits, Devices and Applications”, New Delhi, 2001.

III.       Vedam  Subrahmanyam, “Thyristor Control of Electric Drives”, New Delhi,1998