До питання оцінки стану ізоляції ротора гідрогенератора тепловізійним методом

Abstract

This article addresses the pressing issue of reconstructing the thermal profile of the rotor pole windings of a hydro-generator whilst it is in operation. Given the design of the hydro-generator, it is difficult to determine the temperature of the rotor windings, which rotate during operation, using conventional methods. This paper proposes an approach involving the installation of a row of infrared sensors along the rotor radius, with the output voltage of each sensor being recorded, which is proportional to the measured temperature. At any given moment, only one segment of the rotor winding surface falls within the field of view of the infrared sensors. As the rotor rotates, another part of the winding surface enters the sensors’ field of view. By scanning the entire surface of the rotor windings over the course of a full rotation, we obtain a thermal map of the entire surface of the hydro-generator’s rotor windings. In the event of a localised temperature rise at each pixel, as detected by the corresponding infrared sensor, it is possible to assess the overall thermal condition of the windings. Equally interesting is the task of identifying a single turn or several turns with an elevated temperature, caused by their heating due to deterioration or damage to the insulation. A mathematical model has been developed that allows for the mathematical representation of a single winding turn with an elevated temperature, several turns, or several poles with an elevated temperature. Attention has also been paid to estimating the rate of temperature rise within a specific area of elevated temperature. A device structure is proposed that enables the identification of a single turn with an elevated temperature, allowing operational staff to make prompt decisions regarding the operational capability of the hydro generator. Provision is made for transmitting the temperature values of each pixel of the rotor windings to the operational staff’s computer for further analysis and data accumulation.