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.
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.