Evaluating Lifespan of Corona Armor Tape in Form-Wound Rotating Machines

In form-wound rotating machines, corona armor tape (CAT) is deployed as an outer layer over the coil-insulating materials. However, the CAT is susceptible to degradation caused by ozone, which is generated by partial discharges (PDs). Understanding the CAT's durability in actual operating conditions is crucial, necessitating a precise technique for estimating the CAT's lifespan. This study aims to predict the CAT's lifespan using the Arrhenius law based on chemical reaction kinetics. We focus on the relationship between ozone production and discharge power, and we attempt to predict the CAT's lifespan at any temperature using the Arrhenius plot, with the of PD power serving as a critical parameter. Our findings reveal that the activation energy required for CAT degradation is lower at higher temperatures. Furthermore, the CAT's lifespan at any given temperature is found to exhibit a direct correlation with the power discharged during PD; this underscores the significant impact of discharge power on CAT durability.