DEVICE FOR DIFFERENTIALLY-PHASED PROTECTION Russian patent published in 2007 - IPC H02M7/08 H02H3/28 

FIELD: engineering of devices for protecting asynchronous generators from internal inter-phased short circuits in stator winding.

SUBSTANCE: device includes two protection elements, which consist of current transformers installed in phases of the same name of zero and phase contacts of electric machine, to secondary windings of which primary windings of trans-reactors are connected, edge contacts of secondary windings of trans-reactors are connected to each other through oppositely coupled diodes, connection points of which are connected to one another through two serially connected resistors, an additional protection element, consisting of trans-reactor, primary winding of which is connected to current transformer, installed in phase of the same name of self-excitation capacitors, connected in a star circuit, edge contacts of secondary winding of trans-reactor are connected to analogical contacts of other trans-reactors through oppositely connected diodes, middle contact of secondary winding of trans-reactor is connected to middle contact of secondary winding of trans-reactor which is installed on the side of phase contact of electric machine, to point of connection of resistors and to input of reacting organ, output of which is connected to middle contact of secondary winding of trans-reactor which is installed on the side of zero contact of the electric machine.

EFFECT: expanded functional capabilities.

1 dwg