Historical Trends in Use of Accelerated Aging and Diagnostic Tests for Qualification of Stator Bar/Coil Insulation

Stator bars and coils undergo rigorous qualification tests to ensure their reliability. Among these tests, Voltage Endurance and Thermal Cycling tests play crucial roles. Additionally, diagnostic tests such as Dissipation Factor and Tip-Up, and Partial Discharge measurements are used to assess the insulation condition. For over 35 years, Powertech Labs, a third-party testing facility, has accumulated a comprehensive database of test results from testing coils and bars from various manufacturers, technologies, and test programs. In this study, we analyze the overall trends in test programs and examine results on a broader scale, without delving into individual bar or coil specifics.