There are many different parts that make up the railway electrical propulsion system, including the pantograph, transformer, rectification, DC link, inverter, auxiliary supply, induction motor and other sections. To dissipate braking energy into the railway, a brake resistor is attached to the DC Link. When energy is being lost in the brake resistor, its temperature rises. We need to continuously estimate the temperature on board using the internal clock, especially when the control system is out for some reason and the temperature sensor is not providing us with actual data. This projected temperature at system startup enables us to immediately act to manage the system. In this Paper, I have covered an algorithm for precise temperature estimation that takes into account thermal resistance, thermal capacitance, ambient temperature, initial temperature and the real amount of time it takes for a system to turn down. Estimating the temperature of the brake resistor is an important aspect for ensuring correct operation and safety in the event of control system malfunctions and power outages. By using cutting-edge sensors and algorithms, it is possible to estimate the brake resistors temperature correctly and take the necessary steps to avoid overheating, fire dangers and system failure in general.