Iot Based Transformer Monitoring And Control
Transformers are very important device for transfer of electrical energy. To protect transformer against different types of faults, various methods get used. In this paper, overload protection is established for protection of transformer. Microcontroller based relay is used for protection of transformer. Simulation circuit is designed in proteus software and programming is done in MPLAB software. In this research, hardware and software of microcontroller-based relay has been explained and designed.
Introduction
The transformer is very expensive and vital equipment in the electric power system. Hence protection of transformer is very important. Transformers are used in many applications i. e. from small distribution transformers serving one or more users to very large units.
The population is increased day by day, therefore there is increase in demands on electrical power. With increase in demand of power increases load hence system become overloaded. Overload affects the efficiency and protection system. To prevent the damaging of the transformer, it involves the control against overcurrent tripping of transformer.
Therefore, a proposed method is chosen to design microcontroller-based transformer for overload protection. The microcontroller-based relay provides more adjustable characteristics, high accuracy, more flexibility, increased range of setting, reduced size, minimum cost with many functions such as self-monitoring and checking by GSM technology.
Problem formulation
Modern power system requires accurate, reliable technique for detection of faults. Also, it requires real time data monitoring, System requires fast response speed. Microcontroller based system has real time data monitoring, detection of abnormal condition, fast processing speed. It has reduced installation cost and maintenance cost, more flexibility.
Proposed method
Current sensor senses the amount of load current at the secondary of the distribution transformer. Output of the current sensor gets processed by the controller to find out the load current value.
If the load current exceeds the preset value inside the controller relay gets operated immediately. This results into isolation of load from transformer which brings down the load current to zero. So, the transformer gets protected from damage due to overloading. The load current values continuously get transferred to the LCD and android application for monitoring. The GPRS enabled GSM module sends current values to android application.
Principal components
- Microcontroller
- GSM Module
- Current Sensor
- 16x2 LCD
- Relay
PIC16F877A is the brain of this protection circuit. The main advantage of this is, it has inbuilt ADC, which converts analog value to digital value (sampled value). This sampled value compared with preset values and decision is taken according to programming, hence microcontroller is decision making device. It is simple and compact circuit and gives fast response as compared to processor. Power consumption is less for PIC16F877A microcontroller. It can be used anywhere, such as commercial or industrial because it has wide range of temperature. It also provides programmable code protection.
Global system for mobile communication is used for digital cellular communication. Its frequency range is 900 MHz to 1990 MHz. PIC microcontroller sends actual load value to authority by using GSM.
Current sensor is the electrical device which produce an analog output which is proportional to AC input. Sensor can measure current up to 20A.
It is used to display condition of overload as per changes in load and it will be displayed on LCD display. So, we can see normal and abnormal conditions on display. As per this we can take necessary action.
It is an electrically operated switch. All relay contains sensing unit, electric coil powered by AC or DC current. When current exceed their limits, coil actuates which operate either to close open contacts or to open close contacts. Electromechanical relays are electrically operated switch used to isolate circuit and detect fault in the transformer. It gives high reliability, safe disconnection from the main supply. It has longer life.
Circuit diagram
This circuit is designed to monitor overloading and to protect transformer from damage by overloading. Here, Reference value of load is set. If load exceeds reference value then microcontroller send trip signal to transistor and relay will trip within microseconds. As relay will trip, transformer will be disconnected from load. At the same time GSM module will send information to the prescribed mobile numbers.
Observations
Conclusion
This system provides transformer protection using microcontroller-based relay. For transformer current sensing circuit were designed and result have been verified with proteus simulation. Hardware with microcontroller is implementing to verify proposed technique compared with proteus computer simulation. This system provides better and safer protection than any other method. Proposed method is economical and compact in size. It gives better isolation, accurate fault detection and fast response. Hence protection of transformer is done by using microcontroller relay.
