12-21-2010, 04:43 PM
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عضو فعال
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تاريخ التسجيل: Aug 2010
الدولة: Egypt
المشاركات: 68
معدل تقييم المستوى: 14
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Boiler , turbine - c**trol modes
Boiler Master (Firing Rate Demand)
Boiler Master (basic firing rate demand) computati** is dependent ** the Current operating mode like
Coordinated mode,
Boiler Follow mode,
Turbine Follow mode,
Manual mode.
This demand is transmitted in parallel to the fuel and air c**trol sub -loops.
(1) Unit Startup
During the unit startup, Boiler Master is determined as a fixed demand with the rate to obtain the optimum Boiler steam temperature rising and steam flow until HP turbine bypass c**trol valve is fully closed. This demand will be adjusted manually or automatically according to the unit startup mode.
During this period, Main steam pressure is c**trolled by HP turbine bypass c**trol valve. During the unit start up, the operating mode will be Manual Mode both Turbine governor and Boiler Master manual.
(2) Normal operati**
After HP turbine bypass c**trol valve is fully closed, the operating mode will be normally transferred to Coordinated C**trol Mode.
In case of Coordinated C**trol Mode, the turbine governor c**trols MW and Boiler Master c**trols the main steam pressure.
In case of Boiler Follow Mode, Boiler Master also c**trols the main steam pressure.
In case of Boiler Master Manual or load runback, the operating mode becomes Turbine Follow Mode and turbine governor c**trols the main steam pressure.
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