Patent ID: 9103233
Filing Date: 2015-08-11
Classification: F01D,F01K

Abstract:
1. A method for providing reliable trip response on an integrated steam turbine control system, the system including a hydraulic steam-valve actuator with more than two positions, an instrumentation providing a signal proportional to a steam-valve actuator's position, a pilot valve for manipulating a position of the steam-valve actuator's piston, an electro-mechanical pilot-valve actuator containing at least two individually-energized coils including a primary coil and a secondary coil, at least two electric motors, an Uninterruptable Power Supply (UPS), primary and backup control systems and battery power backup, the method comprising: providing power to the electro-mechanical pilot-valve actuator primary coil from a main source; providing power to the electro-mechanical pilot-valve actuator secondary coil from a secondary source if power to the primary coil is lost; sensing main power loss and sensing trip request; and sending a signal to at least one individually energized coil within the electro-mechanical pilot-valve actuator to provide an adequate trip response.