Patent attributes
The well system includes a casing and production tubing and a control unit that can receive measurements of temperature and pressure of fluid in the tubing-casing annulus (TCA). A subsurface safety valve (SSSV) connected to the tubing can switch to an open or closed state in response to a change in pressure of the fluid. An expected thermal expansion or contraction of the TCA fluid is calculated based on the received measurements, and the control unit determines, based on the expected thermal expansion or contraction and on a calculated TCA volume, a volume necessary to be added to or released from the TCA to maintain the fluid within an optimal pressure range. The control unit can also receive an indication of an emergency condition and transmit a signal to activate a release valve to release from the TCA a volume of fluid sufficient to cause the SSSV to close.