Career Episode Writing: Electrical Engineer

pages Pages: 4word Words: 890

Question :

University: University Of Nairobi

Question: 

Write career episode 3 for a CDR of Electrical Engineer.

Show More

Answer :

Introduction

Location: Amman, Jordan

Name of the organization: Architecture and Engineering

Project Title: DESIGN OF A MICROCONTROLLER BASED POWER TRANSFORMER PROTECTION

Position Title: Electrical Engineer

Time frame: 

Background of Work performed

The main aim of this project is to design a microcontroller system that can aid power transformer safety. I have used the systems to evaluate the operating parameters of a transformer and it helped in isolating in quantifying the current flow in the transformer. I have mainly aimed to design a transformer that can detect current above normal operating levels in advance and can aid in isolating the power transformer from the distribution line. I have designed an isolation process to ensure the safety of the transformer and enhancing its longevity by preventing its damage from overheating. I have used a current sensor ACS712x  series to project the interface between power transformer and PIC16F690. I have used a series of relay and switching gears to isolate the transform from the power source in case of any fault. In case of overloading, an operator will be automatically warned by the monochrome LCD that can detect any unusual delay in power transmission. Piezoelectric buzzers are also used to warn an operator in case of current lag. All these tools are monitored and operated by the help of microcontroller. It has been evident to me that in the design process there are various factors that needs to be controlled which calls for the urgent need of cost control and maintenance. I have to be very specific in including the safety measures to avoid any casualties that may occur from any major misfit in the project work. 

Conceptual Framework related to the work:

The Transformer Protection system used in this context covers major concepts and terminologies related to distribution channels of electrical power. The transformer uses the relative process of induction to transfer electrical power from one source to another source quite conveniently. The transfer of power makes uses of electromagnetic field of induction in which the current is created by placing a conductor in a magnetic field. The voltage is induced through the adherence of electrical power equipments to create electromagnetic induction. The equipments include wire brush, solenoid and other magnetic permeable objects.

Microcontroller is basically a semiconductor chip which is designed to control various electronic systems used in various destinations for appropriate use of electrical appliances. Microcontroller has mainly no memory and is proposed to monitor a number of operation at a single point of time. The components of Microcontroller are oscillator, RAM, Program memory, A/D converter and semiconductor chip. It is noted that PIC16F690 microcontroller used in this project is a 20 pin, 8-bit microcontroller used for controlling different units at different substations. I have used the pin for optimizing the input and output parameters of operational activities in the programmable memory of the transmission system.

Review on microcontroller

Fig: A typical microcontroller

(Source- Self Obtained)

Another component used in this project is Liquid Crystal Display, which uses a predominant two layers of polarizing material to reflect the image that is coded through the system. The crystal allows the passage of electric current in such a manner that the light does not pass through it. The principle of the image transfer lies upon the use of Monochrome LCDs that produces either dark or blue images upon transmission. The color LCD uses numerical figures and characters to display a variety of images at 8-bit interfaces. The data can be hatched from a variety of sources that makes use of the enable pin because of its higher frequency relative to the other components.

Discourse on own role performed:

I have monitored various safety measures and environment friendly techniques to install the transformer at the destined location. I have installed a microcontroller in meantime to generate smooth and error free currents for the large proportion of population. It monitors the rate of power consumption by increasing system components to a nominal value and does the demand for optimal power use goes to a greater extent. The consequences of power transmission can be aligned with cases of overload to prevent the transformer from being damaged. My main aim is to protect the electrical components from major electric faults and therefore i have used microcontroller in the eruptive design to eradicate any possible causes of power loss. I have understood the mechanism of instrument transformers, switchgears and protective gears for maintaining the safety of power line to an optimum level. I have coordinated the subordinates about the use of protective gears and switchgears in the transmission system to facilitate appropriate protection system for the transformer. The circuit breaker has an intensive use in stepping down the transfer of stopping the flow of currents at their destined location and breaking the contacts of the system at the destined source where the fault occurs. I have convinced my seniors to use protective gears for the insulation process, which comprises of protective relays as impedance, frequency and voltage regulators. My major aim was to convince my colleagues about the use of several cost effective protective components like circuit breakers, instrument transformers, switchgears and station batteries to ensure the smooth operation of transmission system.


Application of Engineering Knowledge and Skills:

The engineering knowledge’s and skills that I have used in this memorandum are as follows:

Electromagnetic Induction: When a current carrying conductor is placed in a magnetic field an electromagnetic flux equal to the rate of change of flux and proportional to the number of turns in the conductor is induced which is given in the following expression-

  E= n(dⱷ/dt)

Where ⱷ denotes the magnitude of electrical flux in the expression

 Diagrammatic representation of electromagnetic induction

Fig: A typical representation of electromagnetic induction

(Source- Self obtained)

Restricted Earth Fault:

I have used the following scenario to determine the internal causes of fault analysis for any transformer windings that are connected in an inappropriate way. It can detect any fault below the bottom line and segregate the differential relay in accordance to the fault.

Current Sensor:

My knowledge about current sensor enabled me to detect any AC or DC current flowing in the conductor and as such it gave me appropriate proportion to analyze the corresponding digital signal arising from the fault. It helped me in measuring the amount of current in the conductor and controlling other allied devices conducting these currents.

Relay:

The relay is procured to isolate the transformer from main power supply if there is any fault in the power system as such. The relay coil circuit is sensible to any foreign current or overloading and as such it trips the power supply from the main source to ensure the safety of the appliances.

Important Task delegated:    

My main area of performances revolved in this context is to design and manufacture an electrical system that uses microcontroller and other allied devices to protect the power transformer. I am responsible to conduct the following tasks:

  • To design and manufacture an overcurrent relay using PIC microcontroller and a current sensor
  • To develop, analyze and calibrate the current sensor for making the microcontroller a viable source of electrical transmission
  • To develop ADC program in order to convert the analogue sensor output to equivalent digital form by using PIC microcontroller
  • To develop LCD program to display the sensed level and analyze the causes of overheating in advance
  • To develop audiovisual techniques to warn the operator in case of any major electrical faults
  • To develop relay control system program

I have investigated the scope of the work by building transformer protection modules to enable a proper extension of work in case of any current spikes and overloads. I have analyzed the nature of the electrical power system that is aligned with the generation and distribution of electricity to the consumers worldwide. There are various power transmission devices that is used for smoother power transfer as evident to me which comprises of step up and step down transformer protective devices and many more. The power generation techniques involve the model of circuit breaker that automatically exerts a warning signal whenever there is any discrepancy in the power transmission method. I have designed a creative circuit breaker for making heavy networks in case of any faulty power generation. The circuit breaker mainly works on the principle of tripping signals whenever there is a fault detected from any major source and subsequently the circuit breaker closes itself. I have creatively invented the idea of fault prevention by stopping the spreading of the system despite of preventing the flowing of the current. My duty is to protect the equipment from overcurrent, overvoltage and frequency drift that has the potential to destroy the equipment. 

Technical problems faced during the execution of work:

The application of engineering knowledge’s and skills mainly revolves around the insulation techniques to develop protection measures in case of overloading problems. I have catered other problems during my journey through this project, which are given as follows:

  • During designing of the switchgears and various other protective equipments the feed and workable voltage of the transformer system has to be calculated which is a quite rigorous task
  • To monitor the electrical faults a major series of relay networks and isolation system is to be used whose design is quite a complex schedule in this context
  • To increase the life of components and to prevent it from any dangerous faults a constant look after is necessary which often takes a lot of time and efforts and eventually adds up to the overhead cost of the project
  • To detect any problem or casualties in the load centre all other attached substation has to disconnected in order to carry out the correction activity in the destined location which often leads to consumer dissatisfaction and overall power delay
  • The separation of the faulted network from other destined networks often caused unnecessary delays in estimating the original problem and posing possible remedies for its sustainability
  • The main stream of the circuit breaker automatically cuts off the power whenever there is any possible recognition of electrical faults and as a result, it complies with the accidental losses in any hazardous condition. However, there are a lot of conditions which we encountered when the circuit breaker cuts off the power unnecessarily without any fault present in the network
  • It caused us a heavy toll to detect any fault from the large network and even if found it becomes quite difficult to us at tomes to detect the possible causes for it


Creative Strategies devised by me:

I have convinced my team members about the reliability of the power protection components in order to integrate these tools in the manufacturing of transmission lines by making the following strategy-

  1. Reliable- The components of power protection relays uses imperative means to prevent any possible fault propagation at the electrical lines. It responds very quickly if there is any possible faults present in the electrical lines
  2. Selectivity- It is also selective to appropriate any faults that the section may encounter in due times due to irrelevant channeling of power in inappropriate directions, reducing trafficking of electrical powers. By convincing these approach I have been able to convince my seniors about the cost effective method that can be followed as a result of it.
  3. Sensitivity- The sensitivity of the devices remains the major approach in convincing the users to opt for these devices. The devices are sensitive enough to catch any discrepancies occurring at any direction.
  4. Speed- The equipments are fast enough to catch any unreliable relaying loss at the destined locations and as a result can avoid the delay if required to prevent any occurrence of potential threats to the electrical components of the project.

I have adopted the first use first disposal policy to maintain the projectivity of the electrical appliances in a deemed manner. I have briefly categorized different electrical lines based on their thickness and volume to surface area ratio and analysed the impact of sagging on them in order to estimate their appropriate time of disposal. The transformers system is either step up or step down based on the voltage needs and thus i have categorized different switchgears as per their capacity to withstand higher voltage in a proportionate manner. 

Working experience with other team members:

Team working capabilities is an important aspect in featuring the different components of project in a predominant way. It portraits different technical aspects of the project and it also maintains the coordination of team members to bring out their potential energy in a cumulative way. I have understood that the effective support of team members is very important to carry out the delegators of the project in an evident manner and to carry a flawless project wiping out any possible occurrence of discrepancies. The team coordination activity executes all the bidding aspects of the project amongst with making the scheduling and forecasting prospects intact in their place. I have efficiently delivered my ideas about project deliverables to cater the increasing demands of power for executing a flawless project. I have adopted possible means of audiovisuals in order to make my seniors approachable to my reason of adopting microcontroller in the electrical transmission lines. I have also learnt to keep my subordinates as well as my seniors update about my progress and to plan efficiently before carrying out the execution activity in general.

Summary

It is quite evident to me from the above context that the tangible network of current sensor can be used to detect any electrical faults or discrepancies at an earlier stage to devise strategic plans to prevent any possible power loss. It is the most evident solution to optimize the resource parameters present in the project and to effectively maintain the cost. I have also understood the proximity of relay and switchgears in transformer insulation system to prevent any casualty in the electrical transmission system. The counterproductive design in the microcontroller system devices any programmable system in the given schedules as such. I have also summarized the facts about using electrical insulation system in a transmission line which are as follows:

  • Transformer relays uses the unwanted faults of electrical transmission system as an irrelevant source of coverage if any overloading occurs
  • The short circuit, over current, over voltage problems can be negated by the use of circuit breakers at destined location which immediately cut off the loop if any fault propagates
  • The power system can compel the monitoring of power transmission to continuously adapt to the competitive design as such
  • The uses of electromechanical means of corrective relays isolate the transformer system from others in case of any major electrical casualties