One of the most difficult tasks for a robotic system is to perform missions in areas with strong electromagnetic fields, such as power plants and high-voltage power lines. These disturbances affect the reading of onboard sensors and can cause the robot to become unstable or create conditions that make the task at hand an unpredictable one. To mitigate this effect, this work aims to model and validate the electromagnetic interference field around a power line to enable prediction. In this approach, the electromagnetic field of the Power Transmission Line (PTL) is considered as a function of its position, electric current and tower topology. With the prediction, it is possible to correct the disturbances measured by the sensors, which facilitates the work of robotic systems at a short distance from electromagnetic sources. To prove the model effectiveness, theoretical and practical results are demonstrated in the study of PTLs.