Selection of generator star-point grounding resistance in HPP Zakucac
Abstract
The paper presents a computer analysis based on which the appropriate value of the high-voltage high-ohmic active resistor for grounding new generators in the Zakucac HPP was selected. The resistor in question is installed between the star point of the generator stator winding and the earth / grounding conductor. The following three basic criteria are met: a) limiting the generator ground fault current to a value that is not dangerous for its stator winding, b) limiting internal overvoltages at the generator voltage level to values that are not dangerous for the generator itself and associated equipment, c) ensuring the highest possible sensitivity of the 95% ground fault protection of the generator stator winding.
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