Design And Construction Of An Industrial Battery Charger By Thyristor Firing Angle Control

ABSTRACT

This device charges batteries by DC from AC power supply. DC power for a battery charger is derived from a thyristor controlled rectifier system. AC power is applied to a bridge rectifier comprising of diodes and a scr getting desired control from arduino.

The project uses zero crossing point of the waveform which is detected by a comparator whose output is then fed to the microcontroller. The microcontroller provides required delayed triggering control to a scr through opto isolator interface.

Finally the power is applied to the load through the scr in series with the bridge rectifier. The rectified and controlled DC output is given to the load i.e., a resistor used in our project in place of a battery. The output DC voltage is measured using a multimeter.

CHAPTER ONE

1.1                                                        INTRODUCTION

A battery charger is an electrical device employed in charging batteries that are usually charged by battery charges are the storage batteries also known as “accumulators”.

The project is designed for charging batteries by DC from AC power supply. DC power for a battery charger is derived from a thyristor controlled rectifier system. AC power is applied to a bridge rectifier comprising of diodes and a scr getting desired control from arduino.

The project uses zero crossing point of the waveform which is detected by a comparator whose output is then fed to the arduino. The arduino provides required delayed triggering control to a scr through opto isolator interface.

Finally the power is applied to the load through the scr in series with the bridge rectifier. The rectified and controlled DC output is given to the load i.e., a resistor used in our project in place of a battery. The output DC voltage is measured using a multimeter.

The project can be further enhanced by using direct 230 volt supply instead of 12 volt AC to the bridge rectifier for achieving higher voltage control for charging number of batteries in series.

1.2                                                   AIM OF THE PROJECT

This project is aimed at designing a device for charging batteries by DC from AC power supply. DC power for a battery charger is derived from a thyristor controlled rectifier system.

1.3                                        OBJECTIVES OF THE PROJECT

The objective of the project is to design an industrial charging device that will recharge 12v lead acid battery when discharged using scr. At the end of this work students involved shall be able to:

1. Interface thyristor to arduino.
2. Understand the pin configuration of thyristors

• Understand the working principle of thyristor.

1.4                                      SIGNIFICANCE OF THE PROJECT

This device charges 12v acid battery mainly, however, if the output voltages are adjusted can be used to charge battery of lower or higher voltages. Apart from charging batteries, this device can also be used as a battery level monitor due to the battery level feature it contains.

1.5                                       APPLICATION OF THE PROJECT

Battery charger is used in the following devices for the purpose of recharging device batteries, but this particular charger when adjusted can be used to charge:

1. It is used in inverter
2. It is used in Solar energy system
3. It is used in vehicles
4. It is used in an uninterruptible power supply (UPS), etc.

1.6                                        LIMITATION OF THE PROJECT

The higher cost of this work makes it different from other battery charger and the wiring requires thick wires.

1.7                            ADVANTAGES OF AUTOMATIC CHARGER

Features of this industrial battery charger made it more advantageous than other types and they are as below:

• industrial battery charger has an indicator to indicate when the battery is fully charged
• Built in Indications for showing Full, Empty Levels of any type of battery
• It has a manually operated switch that is used to ON and OFF the entire system.
• It composes of in-built active components which stop charging process when the battery is fully charged.
• It consumed less current but generate high current to the load.

1.8                                                 SCOPE OF THE PROJECT

A battery charger is an electrical device employed in charging batteries that are usually charged by battery charges are the storage batteries also known as “accumulators”.

The battery charge is built in such a way that it delivers a constant value of d.c current into the battery it is charging in the opposite direction from which current flows on the batteries during discharge one cannot successfully design a battery charge without a fundamental understanding of the accumulator because it also makes up the operation.

The project uses zero crossing point of the waveform which is detected by a comparator whose output is then fed to the arduino. The arduino provides required delayed triggering control to a scr through opto isolator interface.

Finally the power is applied to the load through the scr in series with the bridge rectifier. The rectified and controlled DC output is given to the load i.e., a resistor used in our project in place of a battery.