Solid State Drives

Electrical drives play an important role as electro-mechanical energy converters in transportation, material handling and most production processes. The ease of controlling electrical drives is an important aspect for meeting the increasing demands by the user with respect to flexibility and precision, caused by technological progress in industry as well as the need for energy conservation.

At the same time, the control of electrical drives has provided strong incentives to control engineering in general, leading to the development of new control structures and their introduction to other areas of control. This is due to the stringent operating conditions and widely varying specifications – a drive may alternately require control of torque, acceleration, speed or position – and the fact that most electric drives have – in contrast to chemical or thermal processes – well defined structures and consistent dynamic characteristics. During the last few years the field of controlled electrical drives has undergone rapid expansion due mainly to the advances of semiconductors in the form of power electronics as well as analogue and digital signal electronics, eventually culminating in microelectronics and microprocessors. The introduction of electronically switched solid-state power converters has renewed the search for AC motor drives, not subject to the limitations of the mechanical commutator of DC drives; this has created new and difficult control problems. On the other hand, the fast response of electronic power switching devices and their limited overload capacity have made the inclusion of protective control functions essential.

Lesson Plan

Date Period Topics Covered Course Materials
27.06.2016 3,4 Introduction: Electrical Drives, Advantages of electrical drives, Parts of electrical drives, Choice of electrical drives Download Presentation
Download Lecture Notes
 29.06.2016 3 Dynamics of electrical drives: Torque Equations, Speed torque conventions and multi-quadrant operation
 30.06.2016 3 Components of load torques: Friction torque, Windage torque, Torque required to do the useful mechanical work
 30.06.2016  3 Nature and Classification of Load  torques: Active load torque, Passive load torque
 01.07.2016 6 Control of Electrical drives: Modes of operation, Speed control and drive classifications
 02.07.2016 1 Closed loop control of drives
07.07.2016 3 Selection of motor power rating: Thermal model of motor for heating and cooling, Classes of motor duty
08.07.2016 6 Determination of motor rating: Continuous duty, Shot time duty, Intermittent periodic duty
 13.07.2016 3 Steady state analysis of single phase fully controlled converter fed separately excited dc motor Download Presentation
Download Lecture Notes
 14.07.2016 3 Discontinuous conduction
15.07.2016 3 Continuous conduction
16.07.2016 1 Steady state analysis of three phase fully controlled converter fed separately excited dc motor: Motoring operation, Braking operation
20.07.2016 3 Multi-quadrant operation
21.07.2016 3 Chopper fed dc Drive: Motoring control, Braking
22.07.2016 6 Controlling methods: Time ratio control, Current limit control
23.07.2016 1 Four quadrant chopper
27.07.2016 3 Comparison between converter and chopper fed dc drives
03.08.2016 3 Speed control of three phase induction motors: Voltage/ Frequency control
04.08.2016 3 Stator voltage control by ac voltage controllers
17.08.2016 3 Variable frequency control from voltage sources: Variable frequency control of an induction motor, Slip speed control, Torque and power limitations, and modes of operation
18.08.2016 3 Voltage source inverter control: VSI induction motor drives, Braking and multi-quadrant operation, Closed loop speed control
19.08.2016 20.08.2016 6, 1 Variable frequency control from current sources: Current  source inverter control: Regenerative braking, Multi-quadrant operation, Closed loop speed control
24.08.2016 3 Comparison of CSI and VSI drives
31.08.2016  3 Rotor resistance control: Conventional methods, Static rotor resistance control
 01.09.2016 3 Slip power recovery scheme: Static Scherbius drive: Constant torque control
02.09.2016 6 Static Kramer drive: Constant power control
03.09.2016 1 Vector of Field-Oriented Control: Introduction, Comparison between scalar and vector control
07.09.2016 3 DC drive analogy: Equivalent circuit and phasor diagram
08.09.2016 3  Principle of vector control
09.09.2016 3 Direct or Feedback vector control: Salient features
10.09.2016 1 Flux vector estimation
14.09.2016 3 Indirect or feed forward vector control: Phasor diagram
15.09.2016 3 Open loop flux control
16.09.2016 6 Synchronous current control
17.09.2016 1 Direct torque control: Torque expression with stator and rotor fluxes
19.09.2016 3,4 Control strategy of DTC
03.10.2016 3, 4 Digital control: Dedicated hardware systems versus digital control
05.10.2016 3 Digital control of induction motor drives: FOC of a three phase induction motor: Implementation of field orientation
06.10.2016 3 FOC of a CSI fed induction motor
07.10.2016 6 PWM inverter with current control: Adaptation of rotor time constant
08.10.2016 1 Selection of microprocessor / microcontroller
13.10.2016 3 Selection of drives and control schemes: Steel rolling mills: Reversing hot rolling mills, Continuous hot rolling mills
14.10.2016 6 Reversing cold rolled mills, Continuous cold rolling mills, Motors for mill drive
15.10.2016 1 Paper mills: Group drive, Individual drive
17.10.2016 3 Lifts  
17.10.2016 4 Cranes: Requirements of the drive, Drive motors for cranes
19.10.2016 3 dc systems for cranes
20.10.2016 3 ac systems for cranes

Direct Assessment


Tutorial No Tutorial Topics Question Paper Solution Manual
 1 Dynamics of Electrical Drives Download Download
 2 Thermal Model of Motor and Selection of Motor Power Rating Download Download
 3 1-Phase Converter fed dc Drives Download Download
 4 3-Phase Converter fed dc Drives Download Download
 5 Chopper fed dc Drives Download Download
 6 VSI fed IM Drives Download Download
 7 CSI fed IM Drives Download Download
 8 Rotor Resistance Control of IM Drives Download Download

Continuous Assessment Test

CAT No. CAT Topics Question Paper Solution Manual
 1  Drive Characteristics, Converter / Chopper fed dc Motor Drives Download Download