Generator Protection Relay Upgradation Project

This document presents a comprehensive account of a project involving the upgrading of protection relays for a generator. The assignment details the meticulous planning process, utilizing tools like Ms-Project and SAP, to ensure efficient execution. It describes the installation procedures for numerical relays, their configuration with Micom 1 studio software, and the implementation of programmable logic schemes for tripping functions. Rigorous testing using an Omicron kit verifies the effectiveness of various protection features. The document also highlights challenges encountered during testing and the measures taken to address them. Finally, it emphasizes the successful project completion within the stipulated timeline and resources, contributing to improved generator quality and standards.

CAREER EPISODE -3
Project Name: Upgradation of Protection Relays for 4X11kV Generators
a. Introduction
CE3.1: The corresponding episode would describe my work experience in restoration of the
system functionality and upgrading the generator protecting system at Chhukha
Hydropower Plant. The upgradation project ran for 1 year between 2015 and 2016. I
was working at Chhukha Hydropower Plant under Druk Green Power Corporation
Limited. I was selected as the project manager of the project due to my experience as
maintenance engineer for the power plant’s control and protecting system. The project
was required to be completed in the limited budget and duration of time that had been
estimated.
b. Background
CE3.2: Druk Green Power Corporation Limited is the sole electricity production organization
that operates and maintains its 4 large scale hydropower plants within Bhutan. Out of
the 4 hydropower plants of Druk Green Power Corporation Ltd (DGPC), the Chhukha
Hydropower Plant holds the place for the oldest power plant of DGPC as it was the first
hydropower plant of the organization which was built in 1983. However, during the end
of 2014, the plant has been facing some major issues at the generator protecting system.
The issue of slow response of the electromechanical relays with the increment of ageing
and tending to obsolesce within the market were the two issues faced by the mechanical
generator. The project had been initiated to upgrade the generator’s protection system
with the help of replacing the current electromechanical relays with the numerical
relays for protection. The relays were manufactured by the state of the art technology
and it would help in resolving the issues. The procurement, testing, installation, and
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commissioning activities are the in scope items of the project for implementing the
4X11 KV generators numerical relay.
CE3.3: The main objective of the project was for implementing the 4X11 KV generators
numerical protection relay along with the following objectives,
• Preparation of power plant towards automation
• Elimination of maintaining inventory stocks
• Embracing new technology
CE 3.4: Being the project manager and electrical engineer as well, I have to be involved in
project team leading, dismantling the current relays, connected wiring circuits,
installation of the numerical protection relays, test process and commission process of
relay, daily progress monitoring for the work, and ensuring that the work place safety
is implied. The following diagram would show the contemporary organogram
depicting my position in the green block below,
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Figure 1: Shows the Organizational structure of Chhukha Hydropower Plant
CE 3.5: I was assigned the task to restoration of the stator of the generator-1 of Chhukha
Hydropower Plant and was assured by the Executive Engineer to be assisted completely
from other non-technical and technical staffs present in Chhukha Hydropower Plant. I
had to play the role of project manager by managing and leading the project team for
installing, testing, and commissioning the relays (microprocessor based) for the 4X11
KV relays. The project activities had required the knowledge of switchgear and power
system along with experience of practical implementation of the knowledge at the
power plant. The project would also comprise of ensuring the project successful
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Chief Engineer
Maintenance
Division
Control &
Protection
Unit(C&PU)
Generator
Mainteannce
Unit(GMU)
Turbine
Maintenance
Unit(TMU)
Switchyard
Maintenance
Unit(SMU)
Operation
Division Civil Dision Human
Resource
and
Administratio
n Dvision
Finance
Division
Technical Support
Unit(TSU)

completion with the help of leadership attributes and management skills. I was
responsible for,
 Development of the technical specifications for drawing of the schematic protection
circuit and numerical relays
 Using the bidding documents for financial and technical evaluation that have been
submitted by the potential bidders
 Supervising the process of dismantling the current electromechanical relays of the
generator along with its connected wiring circuits
 Installation of the numerical relays with the help of lead team
 Uploading the protection functions for the generator after programming them in the
engineering laptop
 Utilizing the Omicron testing along with primary injection device for testing the
protection functions of the generator
 Commissioning of the relay
 Monitoring of workplace safety
 Monitoring of the project progress report and reporting to higher authority
 Development of project schedule in Microsoft project
 Documentation of project activities for achieving of data
 Development and recruitment of material and manpower resource
c. Personal Engineering Activity
CE3.6: I developed the detail specification needed for implementation of the numerical
protection relay developed for 11KV, 103 MVA generators. The use of the varied
resources and information along with understanding of the switchgear, power systems,
and machinery systems were helpful for me to complete the project successfully.
These knowledge were used for determining the protection function used for relay for
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protecting the generator against the power system faults. I used the reference from
Internal Council on Large Electric Systems (CIGRE), International Electrical and
Electronics Engineer (IEEE), and other online relay manuals on AC generator
protection. It would help in collecting the requirement for the specifications of the
relay that has been internationally set for protection of the AC power generator. I used
the latest automation standard, communication protocol, and extensive drawings and
user specifications for the generator protection.
CE3.7: I evaluated the financial aspect and technical aspect for submitting the documents
along with the committee members of tender evaluation. The tender document was
submitted by Alstom, Schneider Electric and Siemens Pvt Limited on the topic of
selecting manufacturer and supplier of relay. I had presented the relay evaluation
reports for selecting the bidder and it would be approved and selected by the firm. I
even convinced management team for selecting the most appropriate firm that offered
best quality of materials even at high prices as the protection was the major criteria for
the organizational operations. M/s Schneider Electric were provided with the award for
providing most appropriate materials in spite of the higher cost of the material.
CE3.8: I applied different project planning methods and software for developing the plan of
implementation of upgraded relays for the generator projection process. I took the help
of Ms-project for forming the start and the end date of the project along with the help
of System Application Product (SAPY) software. The project milestone and WBS
were made along with development of milestone, each task for the required material,
and manpower. The module was employed for settling the project bill from the finance
department in co-ordination with the budget officer.
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CE3.9 I had conducted a project meeting for making my project team aware about the
project implementation plan and instructed them for following safety procedures
including wearing of Personal Protection Equipment (PPE).
CE3.10: The existing relays were dismantled from the use of the electrochemical protection
relays and its associated circuits. I had ensured the de-energizing of the circuits and
instructed the project team for storing the dismantled relays in safe place.
CE3.11: The numerical protection relays were connected to the main circuit breaker,
governor control, field breaker, input terminals, and master trip relays (X, Y, Z) and
installed with inclusion of the inter circuit wiring. The lead wires emanating from the
voltage and current transformer for the generator side, status of circuit breaker, status of
excitation system, and trip and alarm system.
CE 3.12: I configured numerical relays with the help of Micom 1 studio software and
accessed the system configuration settings. I had entered the voltage and current
values in the setting after the calculation of the parameters for each of the protection
function. I used programmable scheme logic (PSL) editor present in the Micom studio
for developing logical master trip matrix. The logic block named Digital Data Bus
(DDB) that is present in Programmable logic scheme can be assigned to different
protection function.
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Figure 2: Shows the logic functions I developed using programmable scheme logic for
tripping master trip relay, Y
CE 1.11: I tested the relay’s various protection functions using the CMC 256 Omicron
Testing kit which yielded in differential protection, excessive power protection, reverse
power protection, stator earth fault protection, back up impedance protection, over and under
voltage protection, rotor earth fault protection, negative sequence protection, over current
protection, overall differential protection, and dead machine protection.
CE 1.12: I have encountered the problem during relay testing with the 100% stator earth fault
protection test and it is based on 20Hz injection principle. The stator was simulated along
with neutral cable of 3 phase 11KV generator and it showed that the relay did not operated
with the sensing fault of the earth. The analysis resulted in finding the fact that the no
transformers were available and the circuits were attenuated to the relay terminal.
CE 1.13: While execution of the project, I utilized improved project management concepts
while abstaining from the compromising of the safety and environment acts. I had monitored
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the project activities and its progress for ensuring that the visual records for the project are
kept successfully. I used personal protection equipment (PPE) for ensuring that the men at
work are protected and secured.
d. Summary
CE 1.14: I successfully completed the project in the assigned timeline and resources for
ensuring that the project is helpful for improving the processes of the quality and standards.
The alignment of the improved processes would be helpful for ensuing that the generator
would meet the required standard and quality. I have gained exceptional information with the
help of the project completion.
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