Asset Management Through Effective Transformer
Diagnostics & Condition Monitoring
Nor Asiah Binti Muhamad & Nouruddeen Bashir
Institute of High Voltage and High Current (IVAT)
FKE, Universiti Teknologi Malaysia
Johor Bahru, Malaysia
norasiah@fke.utm.my
nour@fke.utm.my
Abubakar Abdullkareem Suleiman
National Agency for Science and Engineering Infrastructure
(NASENI),
Abuja, Nigeria
aabubakarsule@yahoo.ca
Ali Saeed Alghamdi
Technical and Vocational Training Corporation,
Secondary and Vocational Institute,
21413 Jeddah, KSA
sar_dont2004@hotmail.com
Abstract—Power transformers are the most critical and
important equipment in the power sector. It links power
generation, transmission and distribution. There is a huge
investment required to acquire or replace them and when they
fail, huge losses are incurred in terms of assets, revenue and
customer good will. This huge financial burden due to sudden
losses of power transformers can be minimized through effective
condition monitoring and diagnostics. This paper presents a
computer program developed to interpret the condition of power
transformers by the analyzing the dissolved gases. The computer
program developed using C-Sharp (C#) language under
WINDOWS operating system is used to assess four different
methods of Dissolved Gas Analysis (DGA) technique to predict
the condition of the transformer so as to improve the accuracy of
the interpretation. The result shows an increase in the fault-
analysis classification of these DGA methods by up to 20%.
Keywords- Asset Management; Transformer; Condition
Monitoring; Rogers Ratio; IEC Ratio; Duval Triangle; Key Gas
I. INTRODUCTION
The power transformer is the most critical and important
equipment in the chain of power generation, transmission and
distribution as shown in the fig. 1. From the figure, it can
clearly be noticed to be the only recurring equipment and so its
economic and social value cannot be over emphasized.
Figure 1. Schematic diagram of power generation to delivery chain
Therefore to ensure the reliability and guarantee the
availability of power, effective management of the power
transformer is necessary. The management of the power
transformer will have economic, social and environment
implications. Effective asset management will elongate
equipment life, its reliability and thus improve and optimize
business profitability [1]. The management of power
transformer is essentially through monitoring and maintenance
while it is circuit.
In the power transformer, the degradation of the oil is
identified as one of the major reasons of transformer failures
[2]. This is because the insulation materials degrade at higher
temperatures in the presence of oxygen and moisture causing
thermal stress which affects electrical, chemical, and physical
properties of the oil [3]. The insulating materials of the power
transformer is mainly oil and paper and their degradation will
produce hydrocarbon gases that include Methane (CH
4
),
Hydrogen (H
2
), Ethane (C
2
H
6
), Ethylene (C
2
H
4
), Acetylene
(C
2
H
2
) [4]. Dissolve Gas Analysis (DGA) is one of the most
well established condition monitoring assessment techniques
developed to diagnose the fault condition on oil filled
insulation transformers.
Though the testing of transformer oil for dissolved gases
started around 1956 with the Buchholz relay trigger in
transformers, modern methods are available for DGA analysis.
The methods utilise proportional quantities of the gases to
indirectly interpret partial discharges, hot points, arcing,
combustion, aging and overheating; thus aiming to detect
incipient failures that could end the transformer life.
There are more than 6 known different methods of DGA
fault interpretation technique and so there is the likelihood that
they may vary in their interpretations and each of the known
techniques has its own method of assessing the condition of
transformer. The results from either of this assessment method
vary from each other and so there may be an elusive
conclusion on the condition of the transformer. A combination
of all or some of the assessment techniques will make the
DGA more accurate interpretation.
In view of the foregoing, this paper presents a computer
program that is developed to combine four DGA techniques to
interpret the same data obtained from any power transformer
2012 IEEE International Conference on Power and Energy (PECon), 2-5 December 2012, Kota Kinabalu Sabah, Malaysia
978-1-4673-5019-8/12/$31.00 ©2012 IEEE 212