Power transformer protection Scheme during abnormal conditions

Project Title

Power transformer protection Scheme during abnormal conditions

Project Area of Specialization Electrical/Electronic EngineeringProject Summary

Power transformer is a static devise used for transforming power from one circuit to another without changing frequency. Power transformer is the main source of supplying electricity, but sometimes some faults occur due to which power supply cut off. Over current, over voltage and overload are the main faults by which many serious damages occur in transformers and its repairing time is large and also expensive.

The heat is produced in transformer due to over current, over voltage and overload by which temperature inside the tank become high and some gases are also produced which damage the transformer. Due to these faults, winding of transformer damaged that are expensive in repairing and time consuming. So, to protect transformer from over current, over voltage and from overload we do some protections. In past different fuses and only relays were used without microcontroller for protection purpose. But those protections are not enough because sometimes fuses not work and also manually switching off power transformer takes time that is not good for transformer.

So, for protection of power transformer, we will use different devices such as microcontroller, relays and different sensors which are used for sensing current, voltage and temperature. All the transformers have their rating of current, voltage etc. we will use those values and make a code. In code we will make an algorithm in such a way that if current, voltage and load exceed from nominal values then tripping signal will be given to relays and automatically tripping of power transformer occurs. The type of fault can also be displayed on LCD. That will give us information about which fault occur and our transformer will protect from serious loss.

Project Objectives

• To protect power transformer from over voltage.
• To protect power transformer from over current.
• To protect power transformer from overloading.

These three are the three main objective of our project. Because of these three types of faults many other faults also come in the transformer. Transformer are the main equipment and the most expensive equiptment of transmission, so, the protection should also be very high. some future recommendation of our project are also very interesting, which are as follows

• Based upon this protection unit, a universal protection system will be made, which will be used for all types of transformers.
• A sensor will be interfaced with this protection unit, which will automatically monitor and measure the harmful gases produced inside the transformer.
• By further updating this protection unit, we will be able to monitor the different parameters of the transformer i.e. insulation of winding, dielectric strength and core of transformer. So, that we can predict the life of transformer.
• A single protection device unit having input and output terminals, will be available for the protection of transformer.

Project Implementation Method

• With the help of microcontroller we are going to control the switching of transformer.
• We are going to protect the transformer from over current, with the help of microcontroller and current sensor.
• We  will protect the transformer from over voltage by using the microcontroller and relays.
• By using some protection devices, we will secure the transformer from over load.

METHODOLOGY

• We will use different protection devices such as microcontroller, relays, sensors and many different equipment to protect the transformer.
• We will use nominal operating values which are mentioned on the transformer and build a code.
• In code we will apply the condition that if any parameter of transformer exceeds the nominal operating condition which are mentioned on the transformer rating, the microcontroller will pass the signal to the co-ordinate relay to trip the transformer from the circuit and by using this technique we will protect our transformer from any severe damage.

Benefits of the Project

Some beneficiaries of our project are as follows

• Will benefit the power houses.
• Directly and indirectly will benefit the Electronics industries.
• Reduce cut of electricity due to increasing load
• Protect the transformer from great loss

Some major application of our project, which will take benifits from our peoject

• Power Plants
• In Electric Utility Companies
• Grid Stations
• Industrial Plants
• Testing Laboratories
• Research Laboratories

Technical Details of Final Deliverable

Step down transfomer: We use step down the voltages by using step down transformer, to measure the voltages. We cannot measure that too much high voltages, so, we must have to step down the voltages.

Rectifier: We use rectifier to convert AC voltages into DC voltages because, microcontroller can only work on DC voltages. So, to convert the AC voltages into DC voltages, we will use the rectifier, so that our microcontroller can do calculations on it and can protect our transformer from any abnormalities.

Filters: We will also use filters in our circuit. By using rectifier circuit, we will convert our DC voltages into DC voltages but still some fluctuations remain in our voltage waveform, which are not good for our microcontroller. So, we will use filters to vanish those fluctuations also form our voltage waveform.   

Voltage protection relay: We are using voltage protective relay to protect our transformer from over voltage. If the voltages exceed from the nominal preset value then the microcontroller will pass the signal to the coordinate relay driver to cut off the circuit and isolate the transformer.

Current sensor: Current sensor will sense the current which is flowing in the circuit every moment, and pass the signal of current value to ADC.
ADC: ADC is used for analog to digital converting purpose. As we know microcontroller work for digital values so, we will convert our information from analog to digital and pass the digital signal to the microcontroller.
Over current protective relay: When the microcontroller detect that the current value exceeds the nominal operating value of the transformer then the signal will be given to the coordinate relay driver to trip the transformer and over current protective relay will isolate the transformer

Final Deliverable of the Project Hardware SystemCore Industry OthersOther Industries Energy Core Technology Artificial Intelligence(AI)Other Technologies OthersSustainable Development Goals Quality Education, Clean Water and Sanitation, Affordable and Clean Energy, Decent Work and Economic Growth, Industry, Innovation and Infrastructure, Reduced Inequality, Sustainable Cities and Communities, Climate Action, Life on Land, Peace and Justice Strong Institutions, Partnerships to achieve the GoalRequired Resources

Item Name	Type	No. of Units	Per Unit Cost (in Rs)	Total (in Rs)
			Total in (Rs)	80000
Microcontroller	Equipment	2	5000	10000
Relays	Equipment	7	500	3500
sensors	Equipment	5	200	1000
transformer	Equipment	1	45520	45520
filters	Equipment	5	200	1000
rectifiers	Equipment	3	660	1980
LCD	Equipment	1	7000	7000
Report and thesis print and other things	Miscellaneous	1	10000	10000