No matter how important they might be, transformers actually are a pretty simple and dependable device. Also, the fact that our power systems simply won’t run without these electric engineering masterpieces makes takes their importance to a whole another level. However, just because they need less care, using transformers without any look over shouldn’t be done in any case. Amongst few but essential things, transformer oil maintenance and analysis is also a part that should not be missed at any cost.
Electrical transformers are the most used electrical machines in any power system. This device plays a crucial role in both transmission and distribution of electricity in a power network. Therefore, transformer oil maintenance and analysis is one of the few things that should be done to maintain a good health of transformers. So, the question is, why not keep the oil levels in transformers up to date?
It is a well-known fact that checking and sustaining oil-levels in electrical engines, turbines and other lubricated equipment plays a crucial role in maintaining their overall condition. The same thing also applies to the transformers.
Transformer oil maintenance and analysis will not just provide information about the oil. In fact, it will also enable us to detect other possible faults, such as contact arching, aging insulation paper and other possible problems. Therefore, transformer oil maintenance and analysis has become an inseparable and indispensable part of any transformer’s support program.
Maintenance Ensures Reliability
Extreme levels of durability and reliability is expected from transformers. However, very less is done to ensure that these machines work at their finest for the longest time possible. Although the chances of transformers failing is very minimal, a timely inspection will only ensure minimum and cost effective maintenance if they do break down. In addition, these devices are the ones that are possible to be replaced ad changed regularly. Thus, this only makes it more important to maximize and maintain their life expectancy and durability through a timely inspection.
Analysis and maintenance of transformers will help us to discover potential problems, solve them and even help to avoid power outages. Some of the checks are also very routine and simple For example, checking for oil leaks. However, other crucial elements such as the oil paper insulating system can only be checked by carrying out a routine inspection of the transformers.
Key factors in Transformer Oil Maintenance and Analysis
By checking the chemical and physical properties of transformer oil, a number of problems that are associated with oil itself or the transformer can be figured out. In addition, in this process, there is also checking for concentrations of certain dissolved gases. Here are some of the most common tests and checks performed during transformer oil maintenance and analysis.
Moisture Content
Offering electrical insulation is one of the primary tasks of any kind of transformer oils. Any sort of increase in the moisture content will result in reduced insulating properties of the oil. This may even result in dielectric breakdowns of the entire system. Checkings should be done with fluctuating temperatures as when the system cools down, any dissolved water will be free and results in fluid degradation and poorer insulation. Similarly, too much of moisture can also result in damage of paper insulation and in result it gives weaker performances. Therefore, moisture content should be checked and maintained thoroughly in a transformer.
Acid Number
Like all industrial oils, transformer oil is also oxidized by treating under the influence high temperatures. Mostly, in presence of oxygen along with small metal particles are used as catalysts. This results in increased Acid Number as carboxylic acids are formed. Additional reactions should be disallowed as it might form sludges and varnish deposits. In some cases, the oil canals might be blocked and oil breakdown may occur as the system won’t cool down well.
Also, the cellulose paper might be affected due to the increased acidity. Degrading oil often produces acids and hydroperoxides which further reduces its insulating behaviors. Acid Number should be checked and maintained thoroughly as its increase goes hand-in-hand with decrease in dielectric strength and increased moisture.
Dielectric Strength
Dielectric strength of transformer oil is defined as the optimum voltage that can be applied across the fluid without any sort of breakdowns. Transformer oils are made to provide insulation under high electrical fields, so any reduced dielectric strength may poi tot that the oil being used in incapable of performing its tasks. Hence, we will have to change the oils. Polar contaminants such as water, oil degradation by products, and cellulose paper breakdown can also reduce the dielectric strength. Therefore, these things should be checked and a good dielectric strength should be maintained in a transformer.
Power Factor and Dissolved Gas Analysis (DGA)
Power factor of insulating oils of transformer simply refers to the ratio of its true power to its apparent power. A high power factor usually means an indication that there is a significant power loss in the insulating oils. This usually occurs due to the result of polar contaminants.
DGA is a process used to determine the concentration of gases in the transformer oils, such as nitrogen, oxygen, carbon monoxide, carbon dioxide, ethane, methane, acetylene and ethylene. Concentration of these gases can be used to tackle certain operational problems that aren’t even related to the oil’s physical and chemical properties. Hence, analyzing the power factor and DGA is an integral part of transformer oil maintenance and analysis.
Furans
Furan derivatives are simply a measure for degradation of the cellulose paper. With time, paper’s polymerization reduces along with its strength. It can be determined by taking a sample of the paper and performing the operation on it. It is simply the result of breakdown of the paper’s polymeric structure.
These are the vital points that should not be ignored in the process of transformer oil maintenance and analysis. Here at BN Mahto Group, we offer the finest distribution transformers in all of Nepal. Also, we provide all the necessary support to make sure that these machines work at the best. So, feel free to contact us if you need the best transformers around.