Online monitoring device and method for one-point grounding resistance of phase modifier rotor

The invention discloses online monitoring equipment and method for one-point grounding resistance of a phase modifier rotor. The equipment comprises at least one infrared temperature measurement camera device arranged at a to-be-monitored rotor, a first sensing device arranged at a water inlet of a to-be-monitored rotor cooling system, a second sensing device arranged at a water outlet of the to-be-monitored rotor cooling system, a communication device and a server, the server processes the received infrared image information to obtain one-point grounding resistance information, judges the credibility of the one-point grounding resistance information according to the water inlet temperature and pressure information and the water outlet temperature and pressure information, and compares the credibility and the one-point grounding resistance information with an alarm threshold value preset in the server; and judging whether to send alarm information according to the comparison result. The equipment has the adva