Function
Main control circuit (HP valve): speed/load PID → control high-pressure main steam valve to stabilize speed/load
Extraction/replenishment circuit (LP valve): Extr/Adm PID → controls the low-pressure extraction/replenishment valve to stabilize the extraction/replenishment header pressure
Ratio/limiter: Coordinate the actions of HP and LP valves to prevent overpressure/overspeed and ensure safe operation of the turbine within the Woodward envelope
Decoupling/coupling mode: HP/LP valve can be configured for independent control (decoupling) or linkage control (coupling), adapting to different process requirements
2. Control mode
Speed control: equal/droop, supports automatic avoidance of critical speed (2-speed band)
Load control: Generator active power closed-loop, supporting DSLC synchronous load distribution (multi machine parallel)
Extraction/replenishment pressure control: single extraction, single replenishment, combined extraction/replenishment control, priority can be automatically switched to Woodward
Auxiliary control: inlet pressure, exhaust pressure, compressor inlet and outlet pressure limit/control
3. Start stop and protection
Automatic start stop sequence: cold/hot start, automatic warm-up, speed increase, over critical, with load
Overspeed protection: dual redundancy of hardware and software, peak speed recording, independent of the speed control circuit
First trip indication: 5 external trip inputs, locking the first trip fault for easy troubleshooting
Zero speed detection: monitoring of shutdown status to prevent false starts
4. Operation and configuration
Local operation: Panel buttons enable start/stop, speed up/down, mode switching, parameter adjustment
Remote control: DCS/PLC achieves remote setting, control, and status monitoring through Modbus
On site programming: 100+parameters can be configured on-site, supporting the modification of dynamic parameters (PID, limiting, etc.) during operation
Configuration tool: dedicated Windows software (ToolKit), offline programming, online debugging, parameter backup

Application
Cogeneration: extraction steam turbine, simultaneous power supply and heating (industrial steam/heating)
Industrial drive: extraction/replenishment turbine drives compressors, pumps, fans (chemical, refining, metallurgy)
Self owned power station: small and medium-sized extraction units to meet the electricity and process steam needs of the factory area
Waste heat recovery: supplementary steam turbine, recovers low-pressure steam energy, improves energy efficiency

WOODWARD 505E｜Overspeed Protection System｜