Robust control of managed pressure drilling

Managed pressure drilling technology is gaining in popularity because of the necessity to mitigate drilling risks while drilling off-shore and also to make it possible to drill in challenging reservoirs. In this paper we have investigated the contribution of various drilling parameters to the variations in simple first order model of drilling. We also present a robust SISO controller for a particular variant of managed pressure drilling in which a choke valve is manipulated to achieve a bottom hole pressure set point. The presented controller can tolerate significant plant model mismatches, can function well under different well conditions and can also handle noisy measurements. A strategy for practical implementation of this controller is also proposed.