A motor is an electro-mechanical device that converts electrical energy to mechanical energy. The very basic principle of functioning of an electrical motor lies on the fact that force is experienced in the direction perpendicular to magnetic field and the current, when field and current are made to interact with each other. Different types of motors have been developed for specific purposes. This course is designed to help students to become familiar with the basic theory, characteristics, construction, operation and application of rotating electrical machines. It includes the direct current motors, synchronous motors and variable speed drives. After completing this course, students will have practical knowledge on how to safely wire and operate electrical rotating machines and their associated metering and starting equipment.
WHO SHOULD COMPLETE THIS COURSE
- Electrical engineers
- Electrical supervisors
- Maintenance technicians
- Managers in-charge of electrical installations
- Project engineers
- Instrumentation engineers
- Team leaders
- Product managers
- Senior managers
- Subject matter experts
COURSE OUTLINE
MOTOR ACTION
- Motor applications in mining
- Energy conversion
- Review – Magnetic field
- Fleming Left hand rule
- A generator or a Motor action
- Fundamental electromechanical converter
AC INDUCTION MOTOR
- Basic construction
- Stator and Rotor
- Equivalent circuit of AC motor
- Motor Performance
SYNCHRONOUS MOTOR
- Synchronous motor action
- Synchronous motor losses
- Applications
INTRODUCTION TO DC MOTOR
- Principles of operation
- DC motor fundamentals
- Electromagnetic circuit electromechanical features of DC machines
- Construction of DC machine
DC MOTORS CLASSIFICATION
- Principles of operation
- Back EMF or Counter EMF
- Separately Exited DC motor
- Series DC Motor
- Shunt Excited DC Motor
SPEED CONTROL OF DC MOTOR
- Speed control
- Characteristics of various types of DC motors
- Electrical braking of DC motors
- Plugging – DC Motors
- Dynamic – DC Motors
- Regenerative Braking – DC Motors
BRUSHLESS AND BLDC MOTORS
- BLDC Motor construction
- BLDC Motor operation
- Comparison of Bruch and Brushless DC motors
- DC Motors for mining applications
VARIABLE SPEED DRIVES
- Need for VSD
- Benefits of variable speed
- Load torque
- Torque load ability curve
- Main types of VSD
TYPES OF MECHANICAL VSD
- Mechanical variable speed methods and speed ratios
- Variable speed belt drives
- Mechanical coupling
- Cone and Friction disc drivers
- Gearboxes
- Synchromesh transmission
- Eddy current coupling
ELECTRICAL VSD & MOTOR STRESSES
- Power electronic converters
- Overall control system
- Protection of VSD components
- Life of the Electrical motor
- Worked example
GEAR BOXES AND BRAKES
- Gear train
- Brake selection
- Brake – torque and energy
- Worked examples
VSD CONTROL SYSTEMS
- Levels of control
- Closed loop feedback control system
- Closed loop VSD
- Cascade loop controller
VECTOR CONTROL
- Sensor less vector control drives
- Vector control performance
- Current feedback
- Speed feedback
- Vector control regulator diagram
MOTOR CONTROL
- Drive control loops
- Direct Torque control
- Thyristor drives
- Ward- leonard system
- Motor control centres
