| 摘要 |
FIELD: relay protective gear for transformers of electric drive power supplies. ^ SUBSTANCE: proposed method includes measurement of sum total of active power in transformer windings and generation of protective-gear output signal in case modulus of this sum exceeds desired fixed power; in addition active loss power is calculated for transformer secondary windings and included in sum total of power; protective-gear output signal is generated when modulus of sum total exceeds desired fixed power for time interval longer than preset time. As an alternative, proposed method for protecting transformer used to feed multiphase controlled or uncontrolled rectifier involves measurement of active power of transformer secondary windings connected to rectifier and their active power loss directly at rectifier output. ^ EFFECT: enhanced measurement accuracy and protective gear reliability. ^ 4 cl, 4 dwg |
