1. System function

1.1Control function

1) Speed control;

2) Unit power control;

3) Adjustable steam extraction and back pressure control;

4) Simultaneous control (ASS);

5) Initial load control;

6) Primary frequency modulation function;

7) Automatic rapid load shedding function (RB);

8) Grid Automatic Generation Control (AGC);

9) Unit Coordinated Control (CSS).

1.2 Limit to

1) Overspeed limit (OPC);

2) Main steam pressure reduction limit (TPL);

3) Turbine vacuum load reduction limit;

4) Power limitation.

1.3Protection function

1) Mechanical overspeed protection: When the unit speed reaches the set value of the emergency governor, close the earth valve and speed control valve, and implement shutdown;

2) Electric overspeed protection (OPT): When the unit speed reaches the set value, close the main throttle valve and speed control valve to implement shutdown;

3) ETS control: Receive instructions from the turbine emergency trip system (ETS), close the main and governing valves, and implement shutdown.

1.4Test function

1) Overspeed protection (OPT) test;

2) Overspeed limit [OPC] test;

3) Valve activity test:

4) Valve tightness test;

5) False synchronization test;

6) Simulation test.

1.5Operating mode

1) Automatic mode: Automatically complete the entire process of starting, accelerating, and loading according to the set unit startup curve (cold, semi hot, hot); Manual intervention is also possible.

2) Operator automatic mode: achieve closed-loop control of unit speed and load according to the target values and change rates set by the operating personnel;

3) Manual remote operation mode (valve position control); The operating personnel implement open-loop control of the unit load through the DEH operation keyboard;

4) Backup control mode: In case of abnormal conditions such as the DEH control system malfunction and the need to exit operation, the operating personnel can pass through it

The backup operation directly controls the REXA actuator remotely or locally, and implements open-loop control of the unit load;

5) Various operation methods can achieve undisturbed switching

2. Electronic control system

2.1Controller selection

1) Provide company F8 and ITC standard controllers;

2) According to user needs, controllers with decentralized control system components that are consistent with the unit can be selected.

3) The controller used: Guodian Zhishen EDPF; Hollysys MACS-II, MACS-III, MACS-V, FOCS; Xinhua XDPS-4000/e; Longyuan Zhenghe LYZH; Kangjisen; Zhejiang University Central Control; Hitachi HIACS-3000, HIACS-5000/M: Westinghouse OVATION; ABB INFI90; FOXBORO; WOODWARD; HONEYWELL and other controllers, as well as our company's F8 distributed control system components and ITC small controllers.

2.2 Structure and configuration

1) The controller adopts redundant configuration, and important signals are processed with two out of three or one out of two redundancy;

2) Standard configuration of control system: operator station, engineer station, standard control cabinet. Configure the operation panel according to user needs.

Proficient in using mainstream control platforms both domestically and internationally, such as ABB, Westinghouse, Hitachi, GE, Honeywell, Xinhua, Hollysys, Nanjing Keyuan, and Guodian Zhishen, for software configuration and hardware engineering design, including engineering design, configuration, complete supply, and corresponding on-site services for new and old power plant renovations.