Dynamic Toolface Estimation for Rotary Steerable Drilling System.

Area of Science:

• Drilling engineering
• Geophysics
• Robotics

Background:

• Accurate Toolface estimation is crucial for directional drilling and dynamic point-the-bit rotary steerable systems (DPRSS).
• Harsh downhole conditions present significant challenges for real-time Toolface measurement.
• Existing methods struggle with noise and complex accelerations encountered during drilling.

Purpose of the Study:

• To develop a novel dynamic Toolface estimator for enhanced drilling operations.
• To improve the accuracy and robustness of Toolface estimation in challenging downhole environments.
• To enable more precise control of rotary steerable systems.

Main Methods:

• Fusion of data from two accelerometers and one gyroscope.
• Implementation of a dual-accelerometer method to compensate for circumferential acceleration.
• Application of a nonlinear Complementary Filter (CF) to mitigate vibration and axial acceleration effects.
• Adaptive determination of the nonlinear CF's natural frequency based on real-time drilling conditions.

Main Results:

• The new dynamic Toolface estimator demonstrated high robustness in validation tests.
• The estimator successfully followed reference Toolface values under typical drilling modes.
• The dual-accelerometer method effectively compensated for circumferential acceleration.
• The nonlinear CF successfully suppressed noise from vibration and axial acceleration.

Conclusions:

• The developed dynamic Toolface estimator offers a significant advancement for drilling engineering.
• The fusion of multiple sensors and advanced filtering techniques leads to improved accuracy and reliability.
• This technology enhances the capabilities of dynamic point-the-bit rotary steerable systems.