حسين تقي زاده انصاري

One of the expensive and important apparatus in the power systems is the power transformer whose health can have an influence on the safe operation of the power grid. Among the parts of power transformers whose health status may affect their performance is oil-impregnated paper (OIP) bushings. Moreover, any defects or faults in OIP bushings can lead to explosions and fire by which the neighboring apparatus can be harmed. Therefore, OIP bushings must be monitored to ensure safe operation of transformer and the power grid. It is important to note that moisture is one of the factors that can damage the OIP bushing. Therefore, effective eva‎luation of the moisture in OIP bushings is crucial to ensure the safe operation of power systems. In recent years, the frequency domain spectroscopy (FDS) method has been widely used to assess the insulation system status because it gives more rich information about the insulation system than the other conventional methods. In this dissertation, several techniques are proposed to eva‎luate the moisture and DP values of OIP bushings using the FDS method. Moreover, all the proposed methods are based on the data extracted from tan⁡δ-f curves of OIP samples. Furthermore, one of the disadvantages of the FDS method is the long measurement time. Therefore, a method is proposed to eva‎luate the insulation system of OIP bushings in a shorter time than the FDS method. All the proposed methods are validated using three 145 kV OIP bushings.

بوشينگ هاي روغني , ترانسفورماتورهاي قدرت , رطوبت , ارزيابي عايقي

OIP Bushings , Power Transformers , moisture , Insulation Assessment

Hossein Taghizade ansari

Dr. Abolfazl Vahedi