What are Turbine Bypass Systems?

Turbine bypass systems in Combined Cycle Power Plants (CCPPs) are utilized to ramp units online and offline, stably controlling Main Steam pressure and Reheat Pressure in the Heat Recovery Steam Generator. In addition, these systems safely maintain vacuum at the condenser. CCPPs are cycled more frequently, therefore making turbine bypass systems utilized more often – further proving how critical they are to plant operations.

Potential Problems

Improperly functioning turbine bypass system valves represent more than just an inconvenience to effective operation of CCPPs. They routinely contribute to unscheduled downtime and trip events. Every unscheduled trip event adds to equivalent plant starts, and greatly reduces the planned maintenance intervals as part of Long Term Service Agreements (LTSAs), causing plants to spend millions of dollars before they should be required to do so.

Our Solution

Through responsive and repeatable performance, our Electraulic™ Actuation enables CCPPs to optimize transitions and eliminate nuisance trips during ramp-up, ramp down and emergency response scenarios. Our actuators provide hydraulic control capable of steps to .05% resolution – completely eliminating the effects of stick-slip inherent of pneumatic actuators. We design our actuators for continuous modulating service and provide stiff, stable control even in the harshest environmental conditions (-40°F to +250°F).