STUDENT INDUSTRIAL WORK EXPERIENCE SCHEME (SIWES) OF LANDMARK UNIVERSITY 2014 PDF

Preview

Summary

TECHNICAL REPORT ON STUDENT INDUSTRIAL WORK EXPERIENCE SCHEME (SIWES) BY EDET DAVID KOKOETTE (10BD000387) COLLEGE OF SCIENCE AND ENGINEERING DEPARTMENT OF ELECTRICAL AND ELECTRONIC ENGINEERING LANDMARK UNIVERSITY AT BOLITE TECHNOLOGY (KLM 4 IDOROKO ROAD OBASANJO B/STOP ELEDI ESTATE) IN PARTIAL FULFI...

Description

TECHNICAL REPORT ON STUDENT INDUSTRIAL WORK EXPERIENCE SCHEME (SIWES) BY EDET DAVID KOKOETTE (10BD000387) COLLEGE OF SCIENCE AND ENGINEERING DEPARTMENT OF ELECTRICAL AND ELECTRONIC ENGINEERING LANDMARK UNIVERSITY AT BOLITE TECHNOLOGY (KLM 4 IDOROKO ROAD OBASANJO B/STOP ELEDI ESTATE) IN PARTIAL FULFILLMENT FOR THE AWARD OF (B.ENGR) BACHELOR IN ELECTRICAL AND ELECTRONIC ENGINEERING OF LANDMARK UNIVERSITY, OMU-ARAN, KWARA STATE

FEBRUARY 2014 1

CERTIFICATION PAGE

UNIVERSITY SUPERVISOR’S NAME:

RANK/POSITION:

DEPARTMENT:

SIGNATURE AND DATE:

2

ABSTRACT This book contains the technical report for the SIWES industrial training. It explains all that was done during the period of the SIWES. It also contains new knowledge and experience acquired by virtue of the industrial training.

There are also some few suggestions as to who should be entitled to the industrial training being all students of tertiary institutions. The experience gained and knowledge acquired can never be got from any institution it has to be on the field and I think all students should have a feel of what work is like before going into it full time. Also it helps students to know where people in their field of study can work satisfactorily especially in their immediate environment.

This report also contains the different equipment that was used to carry out jobs and also insight into the activities of the different departments in the company. Also included are photos and diagrams.

3

TABLE OF CONTENTS Chapter 1………………………………………………………………………………..

10

Introduction……………………………………………………………………..

10

Participation and work done……………………………………………………

11

‘ Chapter 2…………………………………………………………………………………

14

Theoretical framework 2.1 2.2

Department of design and fabrication…………………………………….

14

Department of production…………………..………………………………. 22

2.3

Department of repairs and maintenance………………..……………….

27

2.4

Department sales and distribution …..…………………………………..

2

Chapter 3……………………………………………………………………………….... 3.1

41

Company profile

Chapter 4………………………………………………………………………………… 4.1

Services rendered

4.2

Experienced gained

42

Chapter 5…………………………………………………………………………………. 43 5.1

Challenges Encountered…………………………………………………….41

5.2

Conclusion……………………………………………………………….. 43

5.3

Recommendation …………………………………………. ……………... 42

5.4

References ……………………………………………………………….. 42

4

TABLE OF FIGURES Figure 1.1 Bilte Technology company template ………… ……………………………………. 5 Figure 2.1 Block diagram of a basic inverter ………..………………………………………..... 7 Figure 2.2 Schematic diagram of an inverter charge controller ..………………………………...9 Figure 2.3 Darlington pair transistor ………………....…………………………………………..11 Figure 4.1 Picture of a fault allocating system …….…………………………………………….13 Figure 4.2 test and repairs of inverters …………………………………………………………. 13 Figure 4.3 Transformers used for inverter……..…………………………………………………13 Figure 4.4

Relay units in the AVR…………...………………………………………………….14

Figure 4.5 Test of inverter system ……………………………………………………………….14 Figure 4.6 Inverter cabinet and repairs process ………………………………………………….14 Figure 4.7 Printed circuit design board…………………………………………………………..15 Figure 4.8 Etching of copper ……............……………………………………………………….15 Figure 4.9 Drilling electronic circuit board…………..…………………………………………..15 Figure 4.10 Soldering of electronic component on panel ……………………………...………….16 Figure 4.11 Fault locating system…………….……………………………………………………17 Figure 4.12 Oscilloscope ……………………….…..……………………………………………..18 Figure 4.13 Working with Oscilloscope …...….………………………………………………….19 Figure 4.14 Patching board …………..……….…………………………………………………..20 Figure 4.15 Hand drilling machine ……………………………………………………………… 20 Figure 4.16 Reworking station machine…...…………………………………………………….. 21 Figure 4.17 Earth Tester…………………..………………………………………………………22 Figure 4.18 Fabrications work ……………………………………………….…………………..22 Figure 4.19 circuit design work ……………………...…………………………………………..23 Figure 4.20 Cable joiner personal preparing earth mat…………………………………………..24

5

CHAPTER 1 INTRODUCTION In Bolite technology there are different departments that are responsible for the day to day productions and maintenance of power Inverters system. These departments are responsible for maintaining and improving the infrastructures that have been put in place for the effective production sales and instaurations. It is the policy of the company to introduce IT students to every one of its departments especially the departments that deal with fabrication and maintenance. Therefore I was introduced to each department in the company. The departments are as follows: i)

Department of Design and fabrication

ii)

Department of Production.

iii)

Department of Repairs and maintenance

iv)

Department of sales and Distributions

BOLITE TECHNOLOGY

Bolite Technology Department of design and fabrication

Department of repairs and maintenance

Department of productions

Installations

Department of repairs and maintenance

Sales and service

Fig. 1.1

Being in a company that specialises in renewable energy and maintenance, i was enlightened about services rendered by the departments of Design and fabrication in terms of maintenance work that was carried out here, tests carried out on inverter transformers, etc. I was also privileged to learn about the different parts and functions of power inverters and its transformers, I learnt how to trace faults in inverters, amplifiers, stabilizers and also how to install them. As a company’s industrial training staff it was mandatory to be in attendance of the weekly safety meetings and daily pep talks. Issues like challenges being faced in the departments and also plans for jobs to be carried out daily. 6

CHAPTER 2 THEORETICAL FRAME WORK Our Activities i)

Productions

ii)

Sales and services

iii)

Installations

Productions: Power Inverters; A device that converts DC power into AC power at desired output voltage and frequency is called an Inverter. Phase controlled converters when operated in the inverter mode are called line commutated inverters. But line commutated inverters require at the output terminals an existing AC supply which is used for their commutation. This means that line commutated inverters can’t function as isolated AC voltage sources or as variable frequency generators with DC power at the input. Therefore, voltage level, frequency and waveform on the AC side of the line commutated inverters can’t be changed. On the other hand, force commutated inverters provide an independent AC output voltage of adjustable voltage and adjustable frequency and have therefore much wider application. Inverters can be broadly classified into two types based on their operation: 

Voltage Source Inverters (VSI)



Current Source Inverters (CSI)

Voltage Source Inverters is one in which the DC source has small or negligible impedance. In Other words VSI has stiff DC voltage source at its input terminals. A current source inverter is fed with adjustable current from a DC source of high impedance, i.e.; from a stiff DC current source. In a CSI fed with stiff current source, output current waves are not affected by the load. From view point of connections of semiconductor devices, inverters are classified as: 

Bridge Inverters



Series Inverters



Parallel Inverter

Bridge Inverters are classified as 

Half Bridge



Full Bridge

7

With most PC manufacturers adopting high-efficiency Active PFC power supplies today your equipment may be at risk! Luckily, Bolite-Power PFC Sine-wave series UPS offers an affordable solution with pure sine wave output safeguarding mid- to high end computer systems, servers and networking hardware that use conventional and Active Power Factor Correction (PFC) power supplies. This series solve the critical compatibility issues of non-sine wave UPS products working with computing systems using Active PFC power supplies and ensures equipment do not unexpectedly shutdown or experience harmful stress when switching from AC power to UPS battery power. This innovative solution offers users from home to SMEs clean and stable battery backup while the featured modem lines are protected from surges. With Automatic Voltage Regulation (AVR) stabilizes the AC signal and maintains a safe voltage, this allows the UPS to maintain safe power levels for the connected equipment without resorting to battery power. The multifunction LCD readout provides immediate access to precise information of critical power/battery conditions. Also, this series comes with several other smart designs including the user-friendly control switch and two 5VDC USB 2.0 charging ports on the sleek front panel for the maximum degree of flexibility and manageability. Bolite Technology Inverter offering clean and stable battery backup, PFC Sine-wave Series can significantly increase efficiencies on energy savings therefore save on your electricity expenses! Block Diagram of an Inverter

Fig. 2.1

8

Working Principle of an Inverter The main device is a transformer. Which have 12V-0-12V, a common iron core. But instead we use the power input as 220 volts. Then power output as 12 volts. The way the switch differential is power AC input as 12 volts and output to AC 220 volts. The 12 volts input power source is a battery be Supply into the center tap of the coil 12 volts. This is now considered a power pack or coil primary. The ends of the wire on both sides (points A and B) And it will be connected via a 2-way switch to ground. Which if the switch connected at a point, will cause an electric current number one, flows from the positive terminal of the battery, into the center tab point. Then flows up to the top, through the contacts A of the switch to ground. If the switch is moved from Points of A to the Points of B, would make an electric current 1. Has stopped. Because currents will redirect the flow an electric current is number 2. From the center tap down below. Through contact B of the switch to ground. The 2 way switch will be controlled on-off with the oscillator circuit that as the frequency generator of 50Hz As a result, switch off – on back and forth between Points of A and B with a speed of 50 times per second. Makes an electric current No. 1 and No. 2 alternating flow rate of 50 times per second as well. Which current flowing through the switch all the time like this. Makes magnetic field resulting in swelling and shrinkage and induced across to the 220 volts coil, which is now, considered to be output power, or secondary coil. The resulting voltage, 220V AC 50Hz frequency winding up this series. The voltage available to be supplied, to the various types of electrical voltage to 220 volts AC to operate.

Charge Controller This prevents overcharging and may prevent against over voltage, which can reduces the battery life span.

Component of a Charge Controller 

Resistors



Variable resistors



Diodes

9



LEDs



Connectors



Transistors



capacitors



12V Battery



Relays normally close

Schematic Diagram of an Inverter Charge Controller

Fig. 2.2

Working Principles of an Inverter Charge Controller Circuit A charge controller is an essential part of nearly all power systems that charge batteries whether the power source is PV, wind, hydro, fuel, or utility grid. Its purpose is to keep your batteries properly fed and safe for the long term. The basic functions of a controller are quite simple. Charge controllers block reverse current and prevent battery overcharge. Some controllers also prevent battery over discharge, protect from electrical overload, and/or display battery status and the flow of power. Let's examine each function individually.

Blocking Reverse Current Photovoltaic panels work by pumping current through your battery in one direction. At night, the panels may pass a bit of current in the reverse direction, causing a slight discharge from the battery. (Our term "battery" represents either a single battery or bank of batteries.) The potential

10

loss is minor, but it is easy to prevent. Some types of wind and hydro generators also draw reverse current when they stop (most do not except under fault conditions)

Preventing Overcharge When a battery reaches full charge, it can no longer store incoming energy. If energy continues to be applied at the full rate, the battery voltage gets too high. The battery will also degrade rapidly and may possibly overheat. Excessive voltage can also stress your loads (lights, appliances, etc.) or cause your inverter to shut off. Preventing overcharge is simply a matter of reducing the flow of energy to the battery when the battery reaches a specific voltage. When the voltage drops due to lower sun intensity or an increase in electrical usage, the controller again allows the maximum possible charge. This is called "voltage regulating." It is the most essential function of all charge controllers. The controller "looks at" the voltage, and regulates the battery charging in response. Some controllers regulate the flow of energy to the battery by switching the current fully on or fully off.

Control Set Points vs. Temperature The ideal set points for charge control vary with a battery's temperature. Some controllers have a feature called "temperature compensation." When the controller senses a low battery temperature, it will raise the set points. Otherwise when the battery is cold, it will reduce the charge too soon. If your batteries are exposed to temperature swings greater than about 30° F (17° C), compensation is essential. Some controllers have a temperature sensor built in. Such a controller must be mounted in a place where the temperature is close to that of the batteries. Better controllers have a remote temperature probe, on a small cable. The probe should be attached directly to a battery in order to report its temperature to the controller. An alternative to automatic temperature compensation is to manually adjust the set points (if possible) according to the seasons. It may be sufficient to do this only twice a year, in spring and fall. Overload Protection A circuit is overloaded when the current flowing in it is higher than it can safely handle. This can cause overheating and can even be a fire hazard. Overload can be caused by a fault (short circuit) in the wiring, or by a faulty appliance (like a frozen water pump). Some charge controllers have overload protection built in, usually with a push-button reset. Built-in overload protection can be useful, but most systems require additional protection in the form of fuses or circuit breakers. If you have a circuit with a wire size for which the safe carrying capacity is less than the overload limit of the controller, then you must protect that circuit with a 11

fuse or breaker of a suitably lower amp rating. In any case, follow the manufacturer's requirements and the National Electrical Code for any external fuse or circuit breaker requirements.

Is It Working? How do you know if a controller is malfunctioning? Watch your voltmeter as the batteries reach full charge. Is the voltage reaching (but not exceeding) the appropriate set points for your type of battery? Use your ears and eyes-are the batteries bubbling severely? Is there a lot of moisture accumulation on the battery tops? These are signs of possible overcharge. Are you getting the capacity that you expect from your battery bank? If not, there may be a problem with your controller, and it may be damaging your batteries.

Conclusion The control of battery charging is so important that most manufacturers of high quality batteries (with warranties of five years or longer) specify the requirements for voltage regulation, low voltage disconnect and temperature compensation. When these limits are not respected, it is common for batteries to fail after less than one quarter of their normal life expectancy, regardless of their quality or their cost. The Darlington Pair Transistors It is connected such a way that the current amplified by the first transistor is amplified further by the second one

Fig. 2.3

Sales and Services: In these department, they deals with the sales of the company product and also receive manufacturing product from previous customer (they also give customer services).

12

CHAPTER 3 COMPANY PROFILE Bolite technology is a company which specializes on renewable energy; for the period of 10years, Bolite technology was established on July 2006, the employment sizes is of 20 people, 5 professionals and 15 non professionals It is located at Eledi Estate.KLM 4 Idiroko Road OTA OGUN STATE. Bolite Technology deals with the Productions of: 

Power Inverters



Stabilizers



AVR



Automatic Change Over



Power Amplifiers

They also specialize with the production of: 

speakers



Wind Mill Generation Plant.

Bolite Technology Inverter or Emergency Power System (EPS) utilize state-of-art Microcontroller technology for the supply of lighting, generator, heater, refrigerator, motor, and other apparatus to provide resources during crisis or failure of regular systems. Pure Sine-wave output with the adjustable AVR feature is highly flexible to supply continuous power to various types of loads under all kinds of environments. The large LCD panel showcases comprehensive information including load level, battery level, voltage and other vital equipment status with a push-of-a button. The competitive design has not only make it the best choice generators but flexible enough to be adopted as UPS for computers and other sensitive equipment’s. Benefits： 

Noiseless, Fuel and Maintenance Free



High Charging Current for Quick Recharging- Up to 5 times faster



Bypass Mode Allows for Charge Only



Generator Compatible Allows Longer Runtime



UPS Function for Auto Changeover



Affordable DC Input Voltage- Minimum 12V battery required



Automatic Voltage Regulator(AVR)



Brownout and Over Voltage Protector 13

CHAPTER 4 Services Rendered: 4.1 Participation & Work Done I had the privilege of working with electrical, electronics machines and devices used in the day to day running of activities. Electrical machines like, the fault locating system

Fig. 4.1

Picture of a fault allocating system.  I participated in the testing and repairs of inverters

Fig. 4.2

 I participated in the rectification of a fault that could be cause by electrical surge.  I participated in the windings of a transformer used for inverters

Fig. 4.3

 I assisted in the installations of inverters at homes and companie...