Does anybody have any data about increasing harmonic penetration and possible electrical resonance in EHV transmission systems caused by utility scale renewable with nontraditional (non-synchronous) generation (Solar, PV, Wind, etc)?
What is a common engineering practice of fusing or isolating 69-138kV potential instrument transformers connected directly to the substation bus in order to Doble test or perform other required maintenance without de-energizing the bus?