Transferred voltages in multigrounded systems

Transferred voltages by the neutral grounding appear when a fault to ground occurs in the medium voltage network of the distribution system, when the primary and secondary neutrals are interconnected in the distribution transformers. This phenomenon is particularly important in systems with multigrounded neutrals where a local fault is "seen" by the whole circuit, because of the multiple current paths to earth. So, a ground potential rise, GPR, is presented along the circuit. The GPR magnitudes can add up to many hundreds volts even in points kilometers far from the fault. This work assesses the behavior of GPR along the circuit and identifies the main variables that influence the transferred voltage levels. Simulations are performed in the ATP program, and the results analysis reveals some behaviors not obvious at all, that offer new criteria to manage these transferred voltages.