Telephone Interference from Solar PV Switching

The emergence of solar Photovoltaic (PV) generation has been one the biggest changes in Power Grid past decade. Such plants are generally inverter based and these devices known sources harmonics fundamental frequency ‘supraharmonics’ (distortion range 2 to 150 kHz). It long theorized that due factors such as response service transformers interface PV grid, impedance power system at point common coupling connected near inverters, supraharmonics frequencies localized do not couple grid. Exceptions this general hypothesis have reported Europe, where from wind shown local three-phase three wire Medium Voltage (MV) system. This paper shows four multi-point grounded MV systems, ones used United States (U.S.), application conventional grounding schemes can lead unintended consequence grid through neutral conductor ground circuit. describes a case study which switching led telephone interference for customers located around plant. To determine mechanism by were an investigation emission plant was performed using conducted well radiated measurements. novel setup performing measurements, unique underlying coupled lessons learned process regarding installation practices described paper.