Surtension dans les installations industrielles – Trois causes, Cinq effets, et l’écart d’atténuation
Voltage swells (1.1–1.8 pu, 0.5 les cycles à 1 procès-verbal) cause MOV failures, VFD overvoltage trips, contrainte d'isolation, and PLC reboots — often with delayed, hidden damage. Three causes: SLG fault on ungrounded MV (max 1.73 pu on healthy phases), large load rejection, and capacitor bank switching. PT. PLN Sibolga field case: 3-phase fault produced 1.724 pu swell on phase A — DVR reduced to 0.997 pu simultaneously with sag recovery on phase C.
