Design And Construction Of A Wireless DC Motor Speed Controller

ABSTRACT

This project is titled the design and construction of a wireless dc motor speed controller. That is, varying the speed of DC motor from a remote place without any wire connection. The circuit was designed, and developed using pulse width modulation (PWM).

The pulse width modulation can be achieved in several ways. In the present project, the PWM generation is done using micro- controller. In order to have better speed regulation, it is required to have a feedback from the motor. The feedback can be taken either by using a tachogenerator or an optical encoder or the back EMF itself can be used .In present project, we implemented the feedback by using the EMF of the armature as the feedback signal. Speed control means intentional change of drive speed to a value required for performing the specific work process. This concept of speed control or adjustment should not be taken to include the natural change in speed which occurs due to change in the load on the shaft.

TABLE OF CONTENT

Title Page

Approval Page

Dedication

Acknowledgement

Abstract

Table of Content

CHAPTER ONE

1.0      Introduction

1.1      Advantages of wireless dc motor speed control

1.2      Application of wireless dc motor speed control

CHAPTER TWO

2.0     Literature review

2.1      Wireless DC Motor Speed Control Background

2.2 When Wireless DC Motor Control is Not the Solution

2.3 Emerging Wireless DC Motor Control – Bluetooth 4.0

2.4 Review of Types of Wireless DC Motor Control Connections

CHAPTER THREE

3.0    Construction

3.1      Block diagram

3.2 Wireless dc motor speed control circuit using IR and ic555

3.3 Circuit description

3.4 Power supply unit

3.5 Power supply components

3.6 Description of components used

CHAPTER FOUR

4.0      Construction Procedure and Testing

4.1      Casing and Packaging

4.2      Assembling of Sections

4.3      Testing of System Operation

4.4      Cost Analysis

CHAPTER FIVE

5.0      Conclusion

5.1      Recommendation

CHAPTER ONE

1.0                                                        INTRODUCTION

A DC motor is a mechanically commutated electric motor powered from direct current (DC). The stator is stationary in space by definition and therefore the current in the rotor is switched by the commutator to also be stationary in space. This is how the relative angle between the stator and rotor magnetic flux is maintained near 90 degrees, which generates the maximum torque.

DC motors have a rotating armature winding (winding in which a voltage is induced) but non-rotating armature magnetic field and a static field winding (winding that produce the main magnetic flux) or permanent magnet. Different connections of the field and armature winding provide different inherent speed/torque regulation characteristics. The speed of a DC motor can be controlled by changing the voltage applied to the armature or by changing the field current. The introduction of variable resistance in the armature circuit or field circuit allowed speed control. Modern DC motors are often controlled by power electronics systems called DC drives.

The introduction of DC motors to run machinery eliminated the need for local steam or internal combustion engines, and line shaft drive systems. DC motors can operate directly from rechargeable batteries, providing the motive power for the first electric vehicles. Today DC motors are still found in applications as small as toys and disk drives, or in large sizes to operate steel rolling mills and paper machines.

Direct currents (DC) motors have been used in variable speed drives for a long time. The versatile characteristics of dc motors can provide high starting torques which is required for traction drives. Control over a wide speed range, both below and above the rated speed can be very easily achieved. The methods of speed control are simpler and less expensive than those of alternating current motors. There are different techniques available for the speed control of DC motors. The phase control method is widely adopted, but has certain limitations mainly it generates harmonics on the power line and it also has got pf when operated lower speeds. The second method is PWM technique, which has got better advantages over the phase control.

In the proposed project, wireless dc motor speed control is been designed. That is, varying the speed of DC motor from a remote place without any wire connection. The circuit was designed, and developed using pulse width modulation (PWM).

The pulse width modulation can be achieved in several ways. In the present project, the PWM generation is done using micro- controller. In order to have better speed regulation, it is required to have a feedback from the motor. The feedback can be taken either by using a tacho-generator or an optical encoder or the back EMF itself can be used .In present project, we implemented the feedback by using the EMF of the armature as the feedback signal. Speed control means intentional change of drive speed to a value required for performing the specific work process. This concept of speed control or adjustment should not be taken to include the natural change in speed which occurs due to change in the load on the shaft.

1.1   ADVANTAGES OF WIRELESS DC MOTOR SPEED CONTROL

1. a) Rapid Results – It is quick and easy to configure, giving results in seconds
2. b) Reliability and Ease of Use – It produces high quality results with high repeatability allowing for
3. c) Rapid and reliable decision making
4. d) Rugged and Reliable – It is a circuit with outstanding durability for field use
5. e) Simple User-friendly interface

1.2 APPLICATION OF WIRELESS DC MOTOR SPEED CONTROL

DC motor possesses excellent torque speed characteristics and offer a wide range of speed control. Though efforts are being made to obtain wide range speed control with ac motors, yet the versatility and flexibility of a dc motors can’t be matched by a ac motors. In view of this, the demand for dc motors would continue undiminished even in figure. A brief discussion regarding the dc motor applications is given below.

1.3   PURPOSE OF THE PROJECT

The purpose of this project is to build a system that can independently and wirelessly control DC motor speed. To do this, the system will need 4 core components: an input system for the transmitter, a wireless transmitter, a wireless receiver, and a motor controller connected to the receiver.

CHAPTER FIVE

CONCLUSION

The dc motor speed is controlled by using power electronic converter circuit. The PWM technique is used to control the speed of dc motor the speed sensor is used to detect the speed and closed loop control systems is used for pulse circuit. The speed pulse train will be based on required input speed. This circuit is useful to operate the dc motors at required speed. The circuit response time is too low.

RECOMMENDATION

This project is designed to be used in our homes, engineering laboratory, and industries where the need for control of dc motor speed is needed. And should be used and maintain by a qualified personnel.