Abstract For limiting the dynamic overreach in impedance relays, there is provided a first comparator for comparing the condition of two periodic alternating quantities which delivers a signal of a definite appearance when a primary condition is fulfilled, and a second comparator which delivers a signal when a secondary condition is fulfilled. The second condition is a limitation of the primary condition. The two comparators are connected to each other to transmit a tripping signal when the primary condition is fulfilled at two consecutive measuring opportunities and when the secondary condition is fulfilled at any measuring opportunity. The primary condition is theta 1 < OR = (argA - argB) < OR = theta 2 and the second condition is theta ''1 < OR = (argA argB) < OR = theta ''2, the secondary condition lying within the primary condition.
Inventors
👤 Michel Chamia
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-10-30 08:05
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/38; H02H3/382
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
112 words
Means for limiting the dynamic overreach in impedance relays and the like comprising a first comparator means (1) for comparing the condition of two periodic alternating quantities (A, B) and including means to deliver a signal of a definite appearance when a primary condition is fulfilled, a second comparator means (2) including means to deliver a signal when a secondary condition is fulfilled, the secondary condition being a limitation of the primary condition, and means connecting the two comparator means to each other to transmit a tripping signal when the primary condition is fulfilled at two consecutive measuring opportunities as well as when the secondary condition is fulfilled at any measuring opportunity.
Claim 2
Dependent Claim
112 words
Means for limiting the dynamic overreach in impedance relays and the like comprising a first comparator means (1) for comparing the condition of two periodic alternating quantities (A, B) and including means to deliver a signal of a definite appearance when a primary condition is fulfilled, a second comparator means (2) including means to deliver a signal when a secondary condition is fulfilled, the secondary condition being a limitation of the primary condition, and means connecting the two comparator means to each other to transmit a tripping signal when the primary condition is fulfilled at two consecutive measuring opportunities as well as when the secondary condition is fulfilled at any measuring opportunity.
Claim 3
Dependent Claim
62 words
Means according to claim 1, in which the comparator means are phase comparators and in which the primary condition is theta 1 < or = (arg A - arg B) < or = theta 2 and the secondary condition is theta ''1 < or = (arg A- arg B) < or = theta ''2, the secondary condition lying within the primary condition.
Claim 4
Dependent Claim
15 words
Means according to claim 2, in which theta 1 0 and theta 2 pi .
Claim 5
Dependent Claim
42 words
Means according to claim 1, in which the comparator means (1, 2) comprise a single comparator for the primary condition and means for obtaining the secondary condition including means for controlling the coincidence and anti-coincidence times between the two quantities (A, B).