Hydraulic system for electronically controlled downhole testing tool

摘要

A hydraulic system is provided for an electronically controlled downhole testing tool. The tool operates on a pressure differential between the well annulus and a substantially atmospheric pressure dump chamber defined in the tool. Power passages communicate a power piston with the well annulus and the dump chamber. Normally closed electric solenoid control valves are disposed directly in the power passages to control fluid flow therethrough. A pressure regulator regulates the pressure differential across the electric solenoid control valves.