Title: Fuzzy Logic Controls Pressure in Fracturing
Fluid Characterization Facility
Author(s): Vincent P. Rivera and L. Mark Farabee,
Halliburton Energy Services
Presentation: SPE Petroleum Computer Conference
Location: Dallas, Texas USA
Date: July 31-August 3, 1994
Abstract: The fuzzy logic pressure control system has
been designed and implemented to deal with the demanding
requirements of the Fracturing Fluid Characterization
Facility (FFCF), a test bed that simulates downhole
conditions for investigating fluid behavior during
fracturing stimulation. Pressure control in the fracture
simulator was difficult because of the wide range of fluid
types and pumping conditions used and by the compliant
structure of the simulator, which uses servo-controlled
actuators to maintain a constant gap width under varying
pressure conditions. The FFCF pressure control system must
handle fluids that vary form water to high-viscosity gel
slurries at flow rates ranging from ¸ to 3 bbl/min.
Conventional control approaches were successful only under
very limited conditions. To solve this problem, a fuzzy
logic controller (FLC) was developed to e a user function in
the FFCF supervisory control and data acquisition system.
Using several fuzzy logic rules, the FLC generates a
position set point for a slurry throttling valve. An
electro-hydraulic directional control valve uses the set
point supplied by the FLC to position the active control
element of the slurry throttling valve.