Patent ID: 9512716
Filing Date: 2016-12-06
CPC Classification: E21B,G01V,H04W

Claim Text:
1. A method for regulating an electromagnetic (“EM”) telemetry signal sent from downhole to surface, the method comprising: (a) determining a value of a controlled parameter of the EM telemetry signal, wherein the controlled parameter comprises one of transmission voltage and transmission current; (b) comparing the value of the controlled parameter to a configuration value; (c) when the value of the controlled parameter differs from the configuration value, adjusting the value of the controlled parameter in a first direction towards the configuration value while monitoring a feedback parameter of the EM telemetry signal, wherein the feedback parameter comprises the other of the transmission voltage and transmission current and varies in response to variations of the controlled parameter; (d) determining a product of the controlled and feedback parameters; (e) comparing the product of the controlled and feedback parameters to a power cutoff threshold; and (f) ceasing to adjust the value of the controlled parameter in the first direction upon the product of the controlled and feedback parameters meeting the power cutoff threshold.