Cable Testing Anomalies for Windpark Testing Applications: Cable Fault Location, Test and Diagnostics

摘要

The US wind industry added approximately 7.6GW of new wind-turbine generation capacity within the US in 2018 according to the American Wind Energy Association (AWEA) and the total wind generation capacity within the United States is approaching 100GW. Demand is still growing for wind-turbine based generation in the US and facilities are constructed in the most expedient and cost-effective manner to meet demand. In the process of meeting those demands, design philosophy, complexity of installation, environmental conditions and deficient workmanship practices may result in reduced system reliability and service life. Moreover, within the wind park industry, there are specific challenges related to Cable Fault Locating (CFL) and Cable Test and Diagnostic (CTD) applications. Long runs of cable, the inability to sectionalize properly, cross-bonding issues, limited to no possibility to use Time Domain Reflectometry (TDR) technique, and cable accessory failures, are some of the unique challenges that are common throughout the industry. Additionally, utilization of native backfill versus engineered backfill, can result in physical sheath damage and higher thermal stresses resulting in loss of life and potential unexpected downtime of the wind generation system. This paper describes the challenges encountered and the methods to overcome these challenges. Authors will elaborate on methods to more effectively troubleshoot and fault locate on these systems. Furthermore, a testing and diagnostics methodology section will cover the fundamentals of diagnostic test methods including sheath fault, tan delta and offline-PD testing to improve system reliability and prevent loss of generation.