【MTE NRI Vs Chromatography Technology】peaceful
Patrick Chiang蒋俊爵
EON Power Technology (Shanghai) Ltd & Action Power Holding Ltd (HK)
Published :September，2014
Abstract: Dissolved-Gas-in-Oil Analysis (DGA) is proven technology for Oil Transformer Faulty Diagnosis and Catastrophic Disaster Prevention measurements. It is the key component or module in today Transformer Online Monitoring System TMS. However, very few people has profound knowledge in understanding the technology change and revolution as from traditional Gas Chromatography (CG) to Photo Acoustic (PA) and nowadays further advance to Near Infra-red (NIR).
In China, due to some special culture in Power Grids and Electricity Companies. The administration and management leaders are always skillful in balancing the complexity of inter-personal relationship with different interests groups. They are very ldom to listen or to give space for end urs or suppliers to rectify some wrong conception or wrong practices which are deemed creating today unfair competition. Their mindt are conrvative for new technology trials and applications.
This article is trying to u very plain and easy wordings for non-technical background people to illustrate the Gas Chromatography (GC) technology is very fundamental and traditional technology in daily works of transformer oil DGA. However, GC is with many constraints that it is not the best and idea choice for the application in Transformer On-line Monitoring (TMS). We hereby to name this application as OLDGA. Adverly, Near Infra-Red (NIR)is the latest Spectrum Technology being dev
eloped by German for the application in OLDGA systems.
study的第三人称单数Key Words: Gas Chromatography (CG), Photo Acoustic (PA), Near Infra-red (NIR), Spectrum Analysis Technology, Absorbed Spectrum, Transformer Online Monitoring (TMS) and On-line Dissolved Gas in Oil (OLDGA),MTE-Hydrocal 1008, GE KELMAN-Transfix, SERVERON-TM8 AND MORGAN SCHAFFER CLISTO 9.
资本积累Recently there is an obvious change in the tender specification as from more than veral decades written for Chromatography Technology gradually (GC) changed to Photo Acoustic Technology (PA).
The author of this article also received many enquiries from many transformer manufacturers or product traders asking questions “is MTE using GC or PA technology?” They always remind me by saying that the committee in the tender board or key purcha decision makers know nothing about tho technologies. They only request our return with simple answer 《Yes》or《NO》. In review of such wrong market practices and conducts, the author has a moral responsibility to write this article to help the general public, particular tho non-technical background ur groups to eliminate their《Bias & Misconception》
Under such intimidation, it provokes for the only choice answer of《Yes》but with remark of “compati
ble to” or “equivalent to” due to commercial considerations.
This is the ill culture and practice under today China Business environment.
Professor Li Kai Shing（李启盛院士/中国电科院）, DAN of China National EPRI criticized such “Yes-man” & “Myopia” culture in the Power & Energy industries. He said that “Leaders and Managers of the Power Grids or Electricity Companies are much focus their attentions on the complexity of inter-personal relationship and balancing the interests of different influential groups. There are many abnormal situation in the tender and purchasing practices. The committee is being leaded by project head with total no knowledge or interest on the technology aspects. Layman are happy to follow the hot gossip, they are very ldom judging their decision according to the Expert’s comments.
No need to say, tho person who are requesting simple respon answer “Yes” or No” is Layman.
Right Front (1) Prof. Li Kai Shing, DAN of China National EPRI, memory photo in his Beijing office.
In fact, we only have 2 main categories in Dissolved Gas-in-Oil Analysis （DGA） Technology
[A] Gas Chromatography气相色谱
（GC），In China, people commonly named
as 《油色谱》。
According to Wiki Encyclopedia, GC is definite as:
Gas chromatography (GC), is a common type of chromatography ud in analytical chemistry for parating and analyzing compounds that can be vaporized without decomposition. Typical us of GC include testing the purity of a particular substance, or parating the different components of a mixture (the relative amounts of such components can also be determined). In some situations, GC may help in identifying a compound. In preparative chromatography, GC can be ud to prepare pure compounds from a mixture.
In gas chromatography, the mobile pha (or
erwin
"moving pha") is a carrier gas , usually an inert gas such as helium or an unreactive gas such as nitrogen. The stationary pha is a microscopic layer of liquid or polymer on an inert solid support, inside a piece of glass or metal tubing called a column (an homage to the fractionating column ud in distillation). The instrument ud to perform gas chromatography is called a gas chromatograph (or
"aerograph",
"gas
parator").
The gaous compounds being analyzed interact with the walls of the column, which is coated with a stationary pha. This caus each compound to elute at a different time, known as the retention time of the compound. The comparison of retention times is what gives GC its analytical ufulness.
GC is invented in 1952 by a British Chemist – Martin APT.
This type of GC DGA equipment is originally designed and ud in laboratory environment. However, with the transformer urs need for On-line
Monitoring
System
(OLTMS),
manufacturers are starting
to modify
the
laboratory equipment with adding on remote communication modules and to convert it for matching the needs of customers and calling
it as Online “OLDGA” that it will installed in open area and inside the transformer bay area.
In the market place, the most popular products are coming from North America (USA and Canada) such as SEVERON True Gas TM8 & MORGAN SCHAFFER Calisto 9. A lmost all the China local manufacturers are supplying and copying this type of GC technology products.
如何处理人际关系
With many years on-field application experience, end urs discover the major disadvantage of GC type OLDGA with the following problems:
1.Carrier Gas means the equipment need a
big cylinder of Gas. This is consumable media that needs frequent replacement.
In order to reduce the consumption of gas, the supplier will tell the end ur to t no more than one measurement per day and then it will extended up to 3 years usage life of gas inside the cylinder. If you switch it to hourly measurement, you have to replace your cylinder in 3 or max. up to 6 months.
2.Replacing cylinders is awful job due to
the expensive and difficulties in transportation and importing purcha from overas for many customers. Some Power Substation are located in very remote locations. Some end customers even stop using and forced to scrap their allocated GC equipment after veral exercis of replacement of gas cylinders. Ur said “I am tortured enough by submitting the request forms back to head office. We always encountered difficulties in arranging the transportation of gas cylinders, you know it is classified as dangerous goods and not general transportation & logistic agents are allowed to handle this type of goods. Electricity Company has a very complicated allocation of job duty and responsibility system. In many occasions, it is very bureaucratic. This type of manning and labor of cylinder exchange will involve or intercour with various departments. Nobody is willing to take full responsibility for this replacement job.”
Carrier gas cylinder
万事如意英文
bottlearenas
3.No substation manager or safety manager
is welcome and willing to e a pressurized gas cylinder inside their transformer bays. Even some smart manufacturer is trying to undercover it by storing the cylinders into a tall & big equipment cabinet.
深圳日语培训
4.Oil Leakage
is very
nsitive fault
for the ur or
operator of
transformer.
According to
general
experience, oil
leakage is very
rare found with the transformer main body tank. However, this type of GC equipment are required two external oil piping for oil pump-in and pump-out operations. Mechanical and human operation errors are commonly claus for the oil leakage from this external oil piping and networks. End ur said the safety and durability of our power transformer is designed for very high safety grade. However, this type of external piping dramatically decread the safety index of the transformer. In some incident cas, the external air is being pumped into the transformer tank due to the leakage in the external piping or the oil pump of GC equipment. It caus our Power Transformer tripped and stopped for rvices. 5.Vacuum & Oil Pumps Failure, Air Injected
into Transformer.
This is the most critical failure of GC type OLDGA with external oil circulation piping and networks. In ca it us vacuum pump for degassing the dissolved gass in oil, any negligence in maintenance,
the diaphragm of the pump will leak and then air being pumped and injected into the power transformer. In HK and Shanghai, some critical accident and transformer tripped accidents were concluded with above pump failure in the investigation reports of tho Electricity Companies. Oil pump failures is also very common problem due to the long distance of external pumping networks, the oil pump is working under
stress all times.
Big vacuum &
oil pumping
6. Chromatography Column or Cord only have
rvices life of approx. 2 ~ 3 years。
Many operators or urs don’t realize that the nsitivity and performance of the
Chromatography
Column
dropped
dramatically in ca the column is being contaminated by the impurity of carrier gas or sampling gass. The rvice life of column is depended on the frequency of usage, the operation temperature and the purity of samples and etc. On-line monitoring urs are not behaved like the laboratory urs that they are more alert the accuracy of the equipment needs
frequent
maintenance and replacement offuckingmachines
testing
media
or
consumable parts.
7. Delicate maintenance and calibration
are the key for good and accuracy performance of GC DGA equipment. Gas leakage, blockage, flow and pressure abnormal; temperature control circuitry failure; mechanical failure of pumps, valves and other moving parts, measuring signal outputs and conversion failure and column nsitivity decreasing are all the common type of problem related to the quality of rvices and maintenance of the GC DGA equipment.
[B]
giveSpectrum
Analysis Technology
(Spectroscopy) is the 2nd categories of DGA with today advancing technology development,
it
will certainly the replacement of GC technology particularly for
the
Transformer DGA
Online
Monitoring
applications.
Many people has a fal perception that Photo Acoustic （PA）is the most advance spectrum technology. In contrast, PA is just the starting point of us for the exploration of usage of spectrum technology but not its finalization of
Standarc Gas Cylinder for calibration of
GC periodically.
Thermo heat constant Bath
6-way
Valve
GC Column
Piping networks Sampling Gas
