Chapter 1

INTRODUCTION

1

1. INTRODUCTION

1.1 Introduction

1.2 Problem statement

1.3 Objective

1.4 Organization of report

2

Chapter 2

RAW MATERIAL, CONSUMABLES AND UTILITIES

3

2. RAW MATERIAL, CONSUMABLES AND UTILITIES

2.1 Component details

4

Chapter 3

ESTIMATION AND COSTING

5

3. RAW MATERIAL ESTIMATION

Table 3.1 Component specification

Sr. no. Component Quantity

1 ATmega328PU microcontroller 01

2 GSM Sim800 Modem 01

3 Temperature sensor (DHT11) 01

6

Chapter 4

MARKET SURVEY

7

4. MARKET SURVEY

4.1 COMPANY-1. (BACSOFT)

4.1.1 Need

8

Chapter 5

SYSTEM DESIGN AND DEVELOPMENT

9

5. SYSTEM DESIGN AND DEVELOPMENT5.1 Block diagram

Fig. 5.1 Block diagram of transformer fault detection system

o Power supply

- As we know the power supply is the main part of any system without power

supply we cannot working the system.

- If the source is not given then who system is work. In our block diagram

power supply is given to the microcontroller for proper working of the system.

o Transformer lead opening-

- With the help of limit switch arrangement we got the indication of transformer

case opening it means theft want to stealing copper of transformer for that

theft must be open this case. And if theft opens this case then indication is

given to the user.

o Motion opening switch-

- As the transformer is move from their base that time this switch should be

open and give indication to user.

o Reset circuit-

- Reset circuit is used for create electrical signal with precise frequency as per

the requirement of transformer they provided.

10

o GSM module-

- GSM module is send the SMS to user about case opening of transformer,

transformer oil measuring and the current location of transformer.

o Microcontroller-

- Microcontroller is nothing but the brain of the system which stored the data in

memory from input and sending to output.

- With the use of microcontroller time to time response from system is goodly

done.

5.2 Circuit diagram

5.2.1 Power supply design

The basic step in the designing of any system is to design the power supply

required for that system. The steps involved in the designing of the power supply are

as follows,

A] Determine the total current that the system sinks from supply.

B] Determine the voltage rating required for different components.

1) Transformer :

The requirement is of 12V DC or GSM modem.

Min Input for IC7805 is = Drop across IC 7805 + Required Output voltage

= 3 V+ 5V

= 8 V

So at Input of 7805 we required 8 V with margin

In bridge rectifier Consider voltage drop across one diode is 0.7V. So, voltage drop of

two diodes is 1.4 V.

Hence, 1.4 V + 8 V = 9.4 V.

So secondary of transformer should deliver at least 10 V AC.

2) Filter:

For filter capacitor design

C=I L∗t1Vr

Where, Vr= ripple voltage

IL = load current

t1= time during which the capacitor being discharge by load current

11

Now,

θ1=sin−1[ E0minE0max ]

So regulated power supply is design for 10 V

Vr = ripple voltage 10% of output voltage

Vr = 1.0 V

E0minE0max

=(10−0.7 )(10+0.7 )

= 9.310.7

θ1=sin−1[ 9.310.7 ]=60 °

At Frequency 50 Hz

T1 = 1/50 = 20 ms

T for 360° = 20ms

For 180° = 10ms

For 60° = 20ms * (60°/360°) = 3.4ms

3) Rectifier:

For bridge circuit

T1 = [time for 90° + time for θ1]

= 5ms + 3.4ms

= 8.4ms

Where,

IL = load current supplied to various IC

IL = (O/P current of IC 89c51 + O/P current of IC 232 + Current req. for display)

= 71mA + 30mA + 15.2 mA

=116.2 mA

Now,

C=I L∗t1Vr

=116.2mA∗8.4ms1V

= 976.04 µf

So we select 1000 µf, 25V electrolytic capacitor

For diode design, PIV = Vm

Vm = E0 max + 2 Vf

= 10.7 + 1.4 V

= 12.1 V

12

I0 = IL /2

= 116.2 mA/ 2

= 58.1 mA

Peak repetitive current

I fm=[ I L (t 1+ t2 ) ]

t 2 .

T1= time for 90° - time for θ1

= 5ms - 3.4ms=1.2ms

I fm=116.2mA (8.6ms+1.2ms )

1.2ms= 833mA

From above specification diode 1N4007 is selected of (PIV, I) = (100V, 1A)

a) The TUF is increased to 0.812 as compared the full wave rectifier.

b) The PIV across each diode is the peak voltage across the load =Vm, not 2Vm as in

the two diode rectifier.

Output of the bridge rectifier is not pure DC and contains some AC some AC

ripples in it. To remove these ripples we have used capacitive filter, which smoothens

the rippled output that we apply to 7805 regulators IC that gives 5V DC. We preferred

to choose capacitor filters since it is cost effective, readily available and not too bulky.

The value of the capacitor filter can be found by following formula,

C=I L∗t1Vr

A regulator is a circuit that supplies a constant voltage regardless of changes

in load current. The regulator used in our project is IC KA7805, which is a three

terminal voltage regulator. A heat sink is used, so that the heat produced by the

regulator dissipating power has a larger area from which to radiate the heat into the air

by holding the case temperature to a much lower value than would result without the

heat sink.

IC KA7805 has an internal thermal overload protection and the internal short

circuit current limiting device.

13

Fig 5.2 Block diagram of DC regulated Power supply

Fig. 5.2 shows the block diagram of a typical power supply. The AC main is

given to the transformer primary to get the required voltage at the secondary. Then it

is applied to the bridge rectifier, which converts the sinusoidal input into full wave

rectified output. The output of the rectifier contains some ripple voltage. To remove

this voltage filter circuit is used. A ripple voltage is nothing but a small value of AC

over DC signal. Then a pure DC is given to the regulator. The function of the

regulator is to give the constant or stable output DC in spite of changes in the load

current.

The reasons for choosing IC regulator is that they are versatile in operation

and relatively inexpensive with features like programmable output, current/voltage

boosting, internal short circuit current limiting, thermal shutdown.

The 78XX are popularly known for regulation has been used. The 78XX series

is a 3-terminal positive voltage regulator and 79XX series is a 3-terminal negative

voltage regulator.

As name suggests it transforms the voltage level from one level to another.

Transformer used is the step down transformer to step 230 V to 15 V. It provides

isolation too from the mains.

14

Fig. 5.4 Circuit diagram of DC regulated power supply

5.2.2 Clock circuit

Generally quartz crystal and ceramic capacitors are used for this purpose. The

crystal frequency is the basic internal frequency of ATmega328 microcontroller.

Minimum frequencies imply that some internal memories are dynamic and must

always operate above a minimum frequency or data will be lost. Serial data

communication needs often dictate frequency of the oscillator, because of the

requirement that internal counters must divide the basic clock rate to yield standard

communications bit per second’s rates (baud rate). If the basic clock frequency is not

divisible without remainder then the resulting communication frequency is not

standard. We had chosen 16 MHz to avoid noise or irregularity in oscillations.

The oscillator formed by the crystal capacitors and on chip inverter generates

a pulse train at the frequency of the crystal.

5.3 PCB layout

There are many PCB layout design software available, as shown below

• AutoTRAX EDA

• CadsoftEAGLE

• DipTrace by Novarm

• Cadstar by Zuken

• CR5000 by Zuken

• TARGET 3001!

• Kicad, open-source suite

• PADS by Mentor Graphics

• Proteus

This project is designed using Cadsoft EAGLE 7.2 Professional for PCB Layout

Designing.

15

5.3.1 About EAGLE

EAGLE (Easily Applicable Graphical Layout Editor) is a PCB design

software to design an electronic schematic and lay out a printed circuit board (PCB).

Eagle is a PCB design software package consisting of a schematics editor, a PCB

editor and an autorouter module. The software comes with an extensive library of

components, but a library editor is also available to design new parts or modify

existing ones.

Eagle is made by CadSoft (http://cadsoft.de), and this software is available in

three versions. The Light-version is limited to one sheet of schematics and half euro-

card format (80x100 mm), but can be used under the terms of the freeware license for

non-commercial use. This software can be downloaded from CadSoft’s homepage, for

Windows or Linux.

Fig. 5.5 PCB layout of Microcontroller board

16

Fig. 5.6 PCB layout of Power supply

5.4 Programming

5.4.1 Algorithm

Step 1:Start

Step 2:Clear all memory

Step 3:Turn off all the LED's

Step 4:Initialize LCD

Step 5:Display Initial messages on LCD

Step 6:Check if any sensor is ON

Step 7:If YES then turn on respective LED and activate GSM modem to send SMS

Step 8:If NO then check for sensor value

Step 9: If YES then turn on respective LED and activate GSM modem to send SMS

Step 10:Repeat from step 6 to 9

17

5.4.2 Flowchart

Fig. 5.7 Flowchart

18

Chapter 6

TESTING AND PERFORMANCE ANALYSIS

19

6. TESTING AND PERFORMANCE ANALYSIS

6.1 Result and Findings

(a) (b)Photo 6.1 Screenshot of received message from system

6.2 System testing

Photo 6.2 System displaying Initial messages at start

20

Chapter 7

CONCLUSIONS

21

7. CONCLUSIONS

7.1 Conclusions

Transformers are among the most generic and expensive piece of equipment

of the transmission and distribution system. Regular monitoring health condition of

transformer not only is economical also adds to increased reliability. In the past,

maintenance of transformers was done based on a pre-determined schedule. With the

advancement of communication technology now it is possible to receive fault

information of transformer through GSM technology remotely to the operator and

authorities so one can able to take possible solution before converting fault in to fatal

situation. Depending upon fault analysis a prototype model of microcontroller based

transformer health monitoring kit is developed in laboratory.

The system uses a voltage, current, temperature measurement, case opening

alert sensor and the GSM network remote control and data processing combined, so

that the speed of operation and reliability has been improved, and the accuracy of

determine of the system has been greatly improved, reducing the costs of traditional

transformer temperature monitoring system.

7.2. Advantages

1. Use of dedicated sensor for each parameter measurement.

2. Overall system cost is low.

3. No need of fuel input.

4. Small size and portability.

7.3 Disadvantages

1. Temperature limitation due to use of consumer electronic modules.

2. GSM signal range problem.

7.4 Application

This type of remote observation of health condition of transformer not only increases the life of transformer but also

22

increases mean down time of transformer there by increased reliability and decreased cost of power system operations.

7.5 Future scope

To overcome disadvantages of this system, an industrial/military graded

module need to be used to increase overall system reliability. A global positioning

system (GPS) system can also be interfaced to get exact location of distribution

transformer. The complete system can also be integrated on a single multilayer PCB

to reduce overall system size. More sensors can be also interfaced to monitor other

parameters like oil level, position, oil temperature etc.

23