摘要 |
FIELD: electricity. ^ SUBSTANCE: invention can be used in relay protection of distribution networks, for simple transformer differential protection and for cutting-off lines with tapped transformers, when there is need for better offset of magnetising-current inrush. The relay allows for locating the output parametre on well-defined regions before the measuring output electronic relay. The parametre lies in the region of large values, determined by a special reference voltage, in case of short circuit, while at large dissipation of this current, considerably lower - parametre at unbalance current of differential protection, or at operating current of the line in case of cuff-off of the line. The actuating device has a fixed setting. For this purpose a rectifier, resonance circuit with a switched electronic component and a reference voltage source are used. ^ EFFECT: increased effectiveness and reliability of protection. ^ 3 dwg |