Relay and method for protecting transformer, and transformer protecting system having the same

摘要

Disclosed are a relay and method for protecting a transformer, and a transformer protecting system having the same. In the present disclosure, whether a transformation ratio of a transformer has been correctly set or not may be determined based on an inner algorithm. If it is determined that the transformation ratio of the transformer has been incorrectly set, a user may be informed to reset the transformation ratio. This may prevent a malfunction of the relay when the system is operated, and may enhance a system stability.

主权项

1. A transformer protecting relay comprising:
an input module configured to allow a user to input a voltage ratio of the transformer and a current ratio between the primary current transformer and the secondary current transformer; and a control module configured to:
calculate a ratio value K according to a formula:V1×I1V2×I2=K, wherein V1 is a primary voltage, V2 is a secondary voltage, I1 is a primary current, and I2 is a secondary current; anddetermine whether the transformer has been incorrectly set before the transformer is operated by determining if K is out of a predetermined range.