Electric Motors and Variable Speed Drives: Selection, Applications, Operation, Diagnostic Testing, Protection, Control, Troubleshooting and Maintenance Course

Course Overview:

This course engages the participants in AC Drive system analysis and its application to industrial systems as well as design of industrial control systems, specifically drives and programmable logic controllers. 

The participants will be able to choose, connect, service and troubleshoot VSDs, with an emphasis on PLC integration, motor burnout, harmonics and EMC/EMI management. 

The course explores the theory behind squirrel cage induction motors, their operational characteristics, and a few key operating principles. 

It also incorporates VSD commissioning, three-phase motor maintenance, bearing replacement, electrical tests and motor troubleshooting. This course is focused on engineers, technicians and other maintenance personnel and strives to constrain supplied electrical machines to operational excellence.

Course Objectives:

By the end of this course, participants will be able to:

• Demonstrate a sound understanding of how AC Variable Speed Drives (VSD's) work
• Install VSDs properly
• Select the right VSD for a given application
• Troubleshoot VSDs competently
• Competently explain how flux-vector control works for drive applications
• Understand squirrel cage induction motors
• Identify the protection and control system requirements for VSD's
• Interface VSD’s with PLCs
• Understand the causes of motor burnout
• Deal effectively with VSD harmonics and EMC/EMI problems

Who Should Attend?

This course is intended for all Instrumentation, Control, Electrical/Electronic Engineers and Technicians, Maintenance Personnel, Plant Technical Staff, and Supervisors.

Course Outlines:

Introduction

• Induction Motors
• Characteristics of squirrel-cage motors
• Stator construction
• Rotor construction
• Air gap
• Operating features
• Standard motor
• Torque

Maintaining Three-Phase Motors

• Maintenance requirements
• Cleaning motors
• Care of stator windings
• Care of rotor
• Overload and single-phase operation problems
• Motor shaft currents
• Induction motor bearings
• Bearing temperatures
• Lubrication and bearing
• Ball bearings
• Sleeve bearings
• Heating of bearings
• Vibration
• Surrounding factors

Machine Disassembly and Reassembly

• Replacing ball bearing
• Rotor removing
• Preparation
• Lifting rotor
• Pulling out rotor
• Inserting rotor

Electrical Testing

• Recommended field insulation test
• AC high potential
• AC megger
• DC high potential
• Measurements of temperature rise
• Thermometer
• Resistance
• Thermocouple

Troubleshooting Electric Motors

• Locating the motor as the problem as quickly as possible
• Determining the reason, the motor failed
• Excessive mechanical load
• Low or high line voltage
• Unbalanced voltages
• Single-phasing
• Excessive duty cycle
• High ambient temperature
• Insufficient ventilation