DEVELOPMENT OF MICROCONTROLLER PROTECTION SYSTEM OF POWER TRANSFORMERS.

The protection of power transformers is a highly intricate issue in the transmission network of the power system. As minimizing the frequency and duration of unwanted interruptions is crucial, there is a significant demand on the protective relays of power transformers. Different protection principles have been suggested and implemented to safeguard transformers from various fault types. Relays that operate based on overcurrent, overcurrent, and overheat principles protect transformers from overloads and external conditions. Differential relays provide protection against internal transformer faults. This study explains and designs the software and hardware of a relay system based on microcontroller, and also presents the system design and testing process. Power transformers are crucial and costly elements in electrical power systems. They can occasionally experience issues due to atmospheric disturbances and transient surges. These issues include internal, that is, faults between parts of the coils, external, that is, external short circuits, overvoltage, overcurrent. This work outlines the design and implementation of a microcontroller-based system for protecting a power transformer. The system consists of devices for internal fault current, magnetizing current, differential protection, overcurrent protection, overvoltage protection and undervoltage protection. In this article, the design of a microcontroller based relay for power transformer protection will be considered. Percentage differential protection, overcurrent and external fault protection, overvoltage and undervoltage protection have been implemented. In the first quarter of the primary current, the rate of change of primary current versus time method is adopted to separate the internal faults of the primary current wave from the current, which depends on the high differential effect of the magnetizing current wave. Protection in power systems is critically significant issue in electric power system design. Electrical power components must be protected from hazardous defects. That is driven by the need to extend component lifespan, reduce unnecessary costs, minimize the frequency of component replacements, and maintain a continuous power supply to support the growing demands of the economy. Therefore this project attempts to design a microcontroller based system that will intelligently monitor faults and offer a safety measure to protect the power transformer in case of power overload. The microcontroller relay has real-time data monitoring, abnormal condition detection, and fast processing speed. The microcontroller relay acts as a multi-function relay. Thus, it further reduces installation costs and maintenance costs. Microcontroller relay is the latest development for all types of faults. So, a microcontroller-based relay is used to protect the power transformer. Correct acceptance and operation of protective relays requires fairly accurate reproduction of abnormal and normal conditions in the power system. This information enters power systems usually through a Current Transformer and a Voltage Transformer. Keywords: Power transformer protection, starting current, differential protection, current transformer, voltage transformer, interest differential protection