AV6 Plus旁路系统功能介绍.pdf

Functional description HP Bypass Station 1. Overview (Diagram D) The HP Bypass System consists of the following parts: • Pressure setpoint generation (Diagrams DA/RA) • Pressure controller (Diagram DB/TB) • Temperature controller (Diagram DC) • Spraywater isolation control (Diagram SD) 2. Pressure setpoint generation 2.1 Startup 2.1.1 Mode Selection (Diagram RA) The BP controller is set to “BP auto” by the operator. Operator sets “startup mode ” with “BP start mode on/off” display button. In “startup mode” the generator it is set to one of the three operating conditions: • Cold start up • Hot start up • restart The “cold start up” is active whenever the main steam pressure is below “Pmin”. The “hot start up” is active when the main steam pressure is above “Pmin” and below “Psync”. The “restart” is active when the pressure is above “Pmin” and the BP valve is closed. The signal “cold/hot start up” is generated when the operating “cold start up” or “hot start up” is on. The “startup mode” is deselected as soon as the pressure reaches “Psync” and the BP valve is open. The “startup mode” is also deselected when the signal “HP Turbine loaded” is active or when the pressure controller is switched to manual. The “fixed pressure mode” is active when the “startup mode” is not on and the “follow mode“ is not on and the “shut down mode” is not on. The “follow mode” is active when the BP valve is closed and the DEH signal “HP Turbine loaded” is active. Further the “foll