INTELLIGENT EFFICIENT SERVO-ACTUATOR FOR A DOWNHOLE PULSER WITH NOVEL BRAKE AND LOCK

摘要

An improved energy efficient intelligent pulser driver used for generating a mud pulse in a MWD (measurement while drilling) application. In the pulser driver, a direct current (DC) powered control circuit activates a three-phase DC brushless reversible rotary electric motor that operates a servo-valve in a linear movement between any open and closed position to cause a main valve to regulate the flow of drilling mud downhole and thus produce a pressure spike in the mud column. The servo-valve is powered both in opening and closing operations by the reversible rotary electric motor which also provides braking and holding of the servo-poppet in any desired part of its linear movement in order to tailor the duration, character and intensity of the mud-pulse.