초록 ▼

A telemetry system involving a shear-type mud pulser valve as the preferred embodiment is described. The control system includes a motor driver for the mud pulser which, in essence, moves one movable plate with respect to a stationary plate to create openings of various sizes. Pressure is sensed uph

A telemetry system involving a shear-type mud pulser valve as the preferred embodiment is described. The control system includes a motor driver for the mud pulser which, in essence, moves one movable plate with respect to a stationary plate to create openings of various sizes. Pressure is sensed uphole of the pulser valve and is compared in real time to the desired pressure pulse amplitude. By allowing different relative rotational positions of the rotatable plate with respect to the stationary plate, different amplitudes can be achieved to further enhance the transmission of data to the surface. The control system compensates for wear in the mud pulser valve itself as well as drastic changes in mud flow and pressure. The configuration is simple and not prone to fouling from grit or other particles in the mud. The system is capable of creating an initial baseline array of a variety of pulse amplitudes, and thereafter providing the required relative rotation between the stationary and rotatable plates so as to be able to duplicate the baseline pulse amplitudes despite changes in the valve condition or in the flowing conditions of the mud.

대표청구항 ▼

1. A control system for generating multilevel signals in a tubular string having a flowpath and a downhole telemetry system using a pulser valve in said flowpath, comprising:a pulser valve operable in multiple positions comprising a maximum and minimum open position and at least one position in betw

1. A control system for generating multilevel signals in a tubular string having a flowpath and a downhole telemetry system using a pulser valve in said flowpath, comprising:a pulser valve operable in multiple positions comprising a maximum and minimum open position and at least one position in between; a driver connected to said pulser valve; and a flowpath mounted controller connected to said driver so as to create pulses with said pulser valve by commanding said driver to re-position said pulser valve in fixed increments independent of flow and pressure conditions of circulating mud.