Root cause analysis for harmonic resonance tripping in wind power plants: An ERCOT case study

Parallel and series harmonic resonance issues associated with wind power plants have gained widespread attention with the consistent growth in wind penetration levels across the world. While there has been significant research on the analytical tools and methodologies to quantify and evaluate harmonic resonance issues in wind power plants, root cause analysis associated with harmonic resonance tripping has received little attention. This paper presents a comprehensive root cause analysis approach for harmonic resonance tripping of wind power plants. The approach has been demonstrated via a case study on an actual wind power plant in ERCOT grid. Detailed harmonic modeling and benchmarking with actual field measurements is presented. Key sensitivity factors spanning grid, wind farm operating conditions and relevant modeling techniques have been considered to identify the “worst case” scenario from harmonic resonance mitigation standpoint. Capacitor bank de-tuning based mitigation has been tested analytically and implemented on the actual wind farm.