Implementation of an Over Voltage and Under Voltage Protection System

The project focuses on creating a protective mechanism for electronic devices by designing a circuit that can detect both over voltage and under voltage situations. The system utilizes an ideal single-phase transformer, a rectifier circuit with center-tapped transformers and diodes, and relay units to control the disconnection of loads based on detected voltage conditions. Capacitors are employed to manage capacitive loads, while choke coils are used for inductive loads, establishing operational limits that trigger protective actions. The solution addresses issues like obtaining complete waveforms from rectifiers by adjusting transformer turns and employs formulas to calculate output voltages under various scenarios. Collaborative efforts within the team ensure adherence to quality standards, with regular consultations on technical challenges and project plans. This comprehensive approach results in a prototype model capable of safeguarding appliances from potential voltage-related damages.

CE 1.1: Project Introduction
Name of the Project : Hardware Implementation of Overvoltage and Under
voltage Protection
Geographical Location : [Please Fill]
Project Duration : [Please Fill]
Organization : [Please Fill]
Position in the Project : Team Member
CE 1.2: Project Background
CE 1.2.1: Characteristics of the Project
The increment in the RMS (Root Mean Square) value of voltage above the 1.1 pu to 1.8
pu is characterized by over voltage. On the other hand, the under voltage condition is being
characterized by the voltage level operating below the optimum value of any electrical
appliances. I have observed that both the condition of under and over voltage has the capability
of negatively affecting the electronic appliances connected to the circuit often results in the
failure and malfunction of the devices. I have further learnt that engagement of the substation for
protection from the sudden surges is dependent in the economy and reliability of the protection
system. Furthermore, often the operational breakdown also creates the transient over voltage that
negatively affects the household and industrial equipments. Therefore, I undertook this project
for the design and implementation of voltage protection system that can be used for the
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household appliances. In this project, I have used current drain of 0.8mA and ensured the voltage
supply between 2.0 V DC to 36 V DC.
CE 1.2.2: Objectives developed for project
During my work in this project, I was focused in implementing a high and low voltage
indicator. I have focused on developing the system with minimum cost that would be applicable
in household electronics and electrical devices. I have further focused on using hardware element
for simulating the protector for under and over voltage condition. For the effective development
of the protection system, I have sub-divided the required work in several objectives as illustrated
below:
 To identify the reason and source for low power quality;
 To evaluate and define the condition for under voltage and over voltage;
 To develop the appropriate plan for preventing the under voltage and overvoltage
situation;
 To develop the required circuit diagram and hardware implementation for the
voltage protection system;
CE 1.2.3: My area of work
I have worked in this project for evaluating the criteria for determining the issue and
problems associated with the power transmission lines. In addition to that, I have developed the
appropriate plan for integrating the under voltage and over voltage criteria for power supply. In
addition to that, based on my academic experience, I have developed the blue print and
developed the implementation of the circuit board for implementing the prototype model of the
system.
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CE 1.2.4: Project Group
Figure 1: Team Member Associated for the completion of the project
CE 1.2.5: My responsibilities throughout the project
I had taken the responsibility for the selection of hardware elements and other electrical
components of low cost in manner to develop the power-circuit protection system for household
appliances. I have further taken more responsibility in implementing the prototype system and
conducted the functionality with household refrigerator. Moreover, I was able to determine and
select the required criteria for checking the inductive load, capacitive load and the resistive load
associated with the power lines. I took more responsibility in gathering the data from various
analysis and implementation plan; that I have extensively utilized while developing the project
documentation report.
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CE 1.3: Distinctive Activity
CE 1.3.1: Comprehending the Theory of the project
The irregularities in the voltage condition of thee power system is often caused faults in
the station, distribution lines and transmission lines due to both natural and unnatural causes. I
have learnt that the unbalanced load in the power lines results in the failure of the electronics
devices and problem related to power quality. The rotor heating is increased because of sequence
negative magnetic flux that is being generated in stator winding. In the current project, I have
applied the logic that the circuit gets disconnected from the appliances while detecting the under
and over voltage condition. I have therefore worked for integrating the mechanism of high
voltage tripping and protect the household devices from damage. Therefore, for the monitoring
and protection I have individually determined the condition of over and under voltage for
inductive load, capacitive load and resistive load in the proposed voltage protection system.
CE 1.3.2: Engineering Knowledge and Skills applied in the project
While developing the resistive load for the hardware design, I have connected a bulb of
50 Watt. I have developed the circuit design in such a way that between the limit 150V to 230V,
the bulb is switched on. For this, I have set the under voltage condition for the voltage below
150V and overvoltage condition above the 230V voltage. I have further used the potentiometer
for setting the appropriate limit for the hardware connected to the system. In order to feed the
supply voltage to the load, I have used relay unit. I have further used 2.50μF±5% capacitor for
connecting the capacitive load to the hardware system. I have set the limit between 148V to
200V where the led light attached to the system is lit. I have characterized under voltage
condition when the voltage is observed below 148v and over voltage condition when the voltage
is observed above 200 V. In addition to that, I have used choke coil for including the inductive
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load and set the operational limit between 148V to 230V. Through this, I was able to effectively
connect thee hardware elements required for the
CE 1.3.3: Accomplishment and Task Performed
For the implementation of the voltage protection system, I have used 230 V, 50 Hz, of
input and integrated an ideal single phase transformer. In addition to that, I have used 0.019 μF
capacitor, 12 V DC voltage source and 120 Ω of resistive load for the implementation. Apart
from that, I have used 10 V operating voltage of relay unit.
CE 1.3.4: Identified Issues and Their Solutions
Issue: I used rectifier circuit in a manner to convert the alternative current to required
direct current for the development of under and over voltage protection system. In this project, I
have used single phase AC current. Therefore I have used center tapped transformer for with two
back-to-back diodes. I have faced significant issues when ii was unable to obtain the complete
wave in rectifier.
Solution: For overcoming the issue, I have implemented the turn in the rectifier twice on
the secondary transformer. Through the application of twice as many turns, I was able to
successfully obtain the required output voltage while keeping the rating of the power unchanged.
Therefore, for determining the output voltage based on no-load, root-mean-square and average
voltage, I have utilized the following formula:
Vdc = Vav = 2 Vpeak / π;
Vrms = V peak/ √2;
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CE 1.3.5: Plan for producing creative and innovative work
I have reviewed various articles, journals and observed; that over voltage condition are
less common than the under voltage condition in power lines. In term of producing innovative
and creative solution through this project, I have determined and characterized the criteria for
both under voltage and over voltage condition. Therefore, I have engaged myself for the
determination of the overvoltage criterion impacting the electrical devices. I have learned that
the energization of the capacitor bank is one of the significant causes of over voltage.
Furthermore, the sudden load deduction due to the disconnection of load creates the over voltage
criteria where I have determined the extra voltage based on the following formula:
v = L di / dt;
In the above equation, I have used v for denoting the over voltage power, L as the line
inductance, t as the time and I as the power. Through this, I was successful in determining the
various types of overvoltage based on the duration of occurrence.
CE 1.3.6: Collaborative work
It was not an individual project, there were two other members in the team. I have
regularly discussed the project implementation plan with the project team in a manner to ensure
the proper standard and quality being followed during the implementation. In addition to that, I
have regularly communicated with the assistant professor for discussing about the technical
issues faced during the development.
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CE 1.4: Project Review
CE 1.4.1: Project Overview
The developed prototype model for over voltage and under voltage protection system was
able to successfully determine the over voltage and the under voltage condition. In addition to
that, the proposed system was able to disconnect the electronics devices from the circuit for
protecting the appliances from damages.
CE 1.4.2: My contribution to work
In this project, I have completed the work activities allocated to me for the timely
completion of the project. I have identified the criteria and the characteristics for detecting the
under voltage and over voltage for the power supply unit. In addition to that, I have used my
knowledge and the engineering skills for implementing the required circuit design for the
protection system.
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