IEC 60216-4-3:2000-Electrical insulating materials-Thermal endurance properties-Part 4-3: Ageing ovens-Multi-chamber ovens, IEC TR 61400-21-3:2019-Wind energy generation systems-Part 21-3: Measurement and assessment of electrical characteristics-Wind turbine harmonic model and its application, IEC 60626-3:2008/AMD1:2012-Amendment 1-Combined flexibl