DC Motors, Speed Controls, Servo Systems

Foreword

Chapter 1. Terminology, Symbols, Systems of Units

1.1. Terminology

1.2. Symbols

1.3. Systems of Units

Chapter 2. DC Motors and Generators

2.1. Basic Theory

Historical Background

Concept of Torque and Power

Law of Electromagnetic Induction

Magnetic Circuit Principles

Working Equations For Voltage and Torque

Commutation

2.2. Motor Comparison

General Description

2.3. Motor Equations and Transfer Function

2.3.1. Electrical Equations

2.3.2. Dynamic Equations

2.3.3. Motor Transfer Function

2.3.4. Torsional Resonance

2.3.5. Speed-Torque Curve

2.4. Power Dissipation in DC Motors

2.4.1. Origins of Power Dissipation

2.4.2. Power Dissipation

2.4.3. Dissipation at Constant Velocity

2.4.4. Dissipation During Incremental Motion

2.5. Thermal Characteristics of DC Motors

2.5.1. Continuous Operation

2.5.2. Intermittent Operation

2.5.3. Thermal Model

2.5.4. Thermal Equations

2.5.5. Thermal Analysis

2.6. Motor Characteristics and Temperature

Armature Resistance

Torque Constant and Voltage Constant

Derating Motor Torque

2.7. Other Characteristics

Mounting

Noise

Noise and Dynamic Balancing

Noise Caused By Side Loading

Bearing Noise

Brush Noise

Environmental Considerations

Brush Wear

Motor Life

Demagnetization of PM Motors

2.8. Moving Coil Motors (MCM)

Moving Coil Motors

Moving Coil Motors and Motor Ratings

Thermal Properties

Resonant Phenomena in Moving Coil Motors

Demagnetizing Current

2.9. Specialty Motors permanent Magnet Motors with Variable KT

2.9.1. Introduction

2.9.2. The Wound-Field Motor

2.9.3. New Motor Types

2.10.Motor Testing

End Play

Radial Play

Shaft Runout

Moment of Inertia

Resistance

Inductance

Friction Torque and Starting Current

No-Load Current and Rotational Losses, No-Load Voltage, No-Load Speed

Demagnetization Current

Torque Constant

Voltage Constant

Electrical Time Constant

Mechanical Time Constant

Torque Ripple

Speed Regulation Constant

Efficiency

Frequency Response

Thermal Resistance

Thermal Time Constant

Air Flow Impedance

Incoming Inspection of Motors

Motor Troubleshooting Chart

2.11. DC Generators

Introduction

Theory

Types of DC Generators

Mounting Features

Temperature Effects

Linearity and Load Effects

2.12. Generator Testing

Output Impedance

Voltage Gradient

Voltage Polarity

Generator Ripple

Temperature Coefficient

Dielectric Test

Linearity

Stability

Incoming Inspection

Generator Troubleshooting Chart

Chapter 3. Unidirectional Speed Controls

3.1. Basic Control Methods

Speed Controllers-An Introduction

Open Loop Controls-The Traditional Approach

Closed-Loop Controls

Speed Controls Vs. Servo Systems

3.2. Velocity Control - Single Quadrant Controller

Voltage and Current of a Single Quadrant Controller

System Operation

Dynamic Braking

3.3. Amplifiers

The Linear Amplifier

Torque Limiting

Dynamic Braking Devices

Reversible Speed Controls

Controlled Acceleration Deceleration System

Switching Amplifiers

Pulse-Width Modulated Amplifiers

Scr Controls

Chapter 4. Speed Controls and Servo Systems

4.1. Servo Theory

Laplace Transformation

Inverse Laplace Transformation

Transfer Functions

Block Diagrams

Transfer Function of a DC Motor

Transfer Function of an Amplifier

Stability

Root Locus Method

4.2 Servo Components

4.2.1. DC Motor

4.2.2. Amplifier

4.2.3. Amplifier-Motor System

4.2.4. Tachometer

4.2.5. Potentiometer

4.2.6. Linear Variation Differential Transformer (LVDT)

4.2.7. Encoders

4.3. Servo Systems

4.3.1. Introduction

4.3.2. Velocity Control Systems

4.3.3. Position Control Systems

4.3.4. Torque Control Systems

4.3.5. Hybrid Control Systems

4.4. System Characteristics

4.4.1. Response of the System to a Step Command

4.4.2. System Bandwidth

4.4.3. Effect of Torsional Resonance

4.5. Servo Amplifiers

4.5.1. Linear Amplifiers

4.5.2. Scr Amplifiers

4.5.3. Switching Amplifiers

4.6. Phase-Locked Servo Systems

4.6.1. Introduction

4.6.2 System Components

4.6.3. System Design and Stability

4.6.4. Special Characteristics

4.7. How To Make Systems Work

4.8. Optimization

4.8.1. Introduction

4.8.2. Velocity Profile Optimization

4.8.3. Coupling Ratio Optimization

4.8.4. Capstan Optimization

4.8.5. Optimum Motor Selection for Incremental Application

4.9. Permanent Magnet Motors for Servo Applications

4.10. Systems and Controls Troubleshooting

Theoretical Failure-Symptom Chart

Chapter 5. Applications

5.1. Introduction

5.2. System Classification and Specification

5.2.1. Classification

5.2.2. Specification

5.3. Motor Selection Criteria

5.3.1. Introduction

5.3.2. When to Specify

5.3.3. What to Consider

5.3.4. Selection Analysis

5.4. Application of Motomatic Systems

5.4.1. Speed Range

5.4.2. Output Torque and Ambient Temperature

5.4.3. Speed Regulation and Stability

5.4.4. Motomatic Speed Control Features

5.4.5. Series E-550 Motomatic Controls

5.4.6. Series E-650 Motomatic Controls

5.5. Application Examples

Office Copying Machine

Hydraulic Motor Drives

Automatic Retrieval System

Speed-Torque Analyzer

Energy Chopper

Laboratory Stirrer

Filament Winding Machine

Rewinder Speed Control

Multi-Motor Control for Industrial Knitting Machines

Semiconductor Manufacturing - Photoresist Spinner

Blood Oxygenator

Infusion Pump

Crystal Pulling Machine

Conveyor Feed Rate Control

Reflowsoldering

Drive for Disc Memory Testing

Variable Speed Tape Recorder

Motor Testing

Tachometer Ripple Voltage

Testing

Torque Limiter

Paper Web Wind-Up Control

Welding Machines

Bidirectional Position Control

Muscle Exerciser - Medical Rehabilitation Device

Punch Press Feed Control

Connector Test Station

Blueprint Machine Drive

Film Scanning Device

Drive for Chart Recorder

Paper Cutting Control

Blood Cell Separator

Adjustable Lathe Feed Rate Control

Contour Lathe

Three-Axis Milling Machine Control

Linear Drive System

Phototypesetter Application

Diamond Sorting System

Printed Circuit Solder Fusing Machine

Component Marking System

5.6. Incremental Motion Applications

5.6.1. Introduction

5.6.2. Selecting the Proper Servomotor for an Incremental Motion System

5.6.3. Tag Printer Feed Drive

5.6.4. Conveyor Drive System

5.6.5. Computer Tape Transport Reel Motor

5.7. Application of P6000 Series Servo Motor Systems

5.7.1. General Description of The P6000 Range of Servo Motor Controls

5.7.2. Standard Options

5.7.3. Standard Drive Packages

5.7.4. Amplifier Installation

5.7.5. Control Adjustments

5.7.6. Customer Connections

5.7.7. Summing Amplifier Compensation

5.7.8. Ramp Generator Adjustment

5.7.9. In Case of Difficulty

5.7.10. Troubleshooting Guide

Chapter 6. Brushless DC Motors

6.1. Introduction

6.2. Definition of a Brushless DC Motor System

6.3. Practical Solutions to Brushless Commutation

6.4. Torque Generation by Various Controller Configurations

6.4.1. The Sinusoidal Control Scheme

6.4.2. Trapezoidal Torque Function

6.5. Commutation Sensor Systems

6.6. Power Control Methods

6.7. Motor Constants

6.8. Brushless DC Tachometers

6.9. Examples of Brushless Motors

6.10. Summary

6.11. Step Motors Versus Brushless DC Motors in Digital Position Systems

6.11.1. Introduction

6.11.2. Step Motor Performance Limitations

6.11.3. Brushless DC Motor Incremental Motion Control

6.11.4 Conclusion

Chapter 7. Electro-Craft Corporation Products

7.1. DC Servomotors

7.2. Servomotor Generators

7.3. Moving Coil Motors

7.4. Tachometers-Generators

7.5. Special Hybrid Motors

7.6. Servomotor Controls and Systems

7.6.1. Motor Speed Controls

7.6.2. P6000 Pulse Width Modulated DC Servomotor Controllers

7.6.3. SD6 Series Servo System Packages

7.6.4. L5000 Linear Servomotor Controls

7.6.5. Options for Use With P6000 and L5000 Controls

7.7. Brushless DC Motors

7.8. Servo Senter

Appendix

A.1. SI System of Units Metric System

Definition of Basic Si Units

Review of Main SI Units and Secondary Units

A.2. Units' Conversion Factors and Tables

Conversion Factors

Torque-Power-Speed Nomograph

Moment of Inertia Conversion Factors

Torque Conversion Factors

Explanation

Relationship of The Speed, Torque and Output Power of a Motor

Inches to Millimeters Conversion

Celsius to Fahrenheit Degrees Conversion

Index