Journal of Zhejiang University SCIENCE A
ISSN 1673-565X(Print), 1862-1775(Online), Monthly

2008   Vol. 9   No. 5   p. 633~639

Research on new type of fast-opening mechanism in steam turbine regulating system and optimization of operation tactic

Xiao-xiao LI¹, Xuan-yin WANG^†‡1, Fu-shang LI²

(¹The State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, Hangzhou 310027, China)
(²Shandong Electrical Power Institute, Jinan 250002, China)
^‡ Corresponding Author
^†E-mail: xywang@zju.edu.cn
Received Sept. 27, 2007; revision accepted Jan. 9, 2008; published online Feb. 23, 2008

Abstract: With the analysis on regulating system in 200 MW steam turbine, the necessity of appending the fast-opening function to the original system is set forth and a new type of fast-opening mechanism is devised. The mathematical model of system is built up. With the use of AMESIM software, the displacement curve of the piston, the force curve of the cartridge valve spool, the pressure curve and the flux curve in the regulation process are obtained based on simulation. The performances of three fast-opening systems composed of cartridge valves with different diameters are compared. Based on the analysis on factors that affect the execution time of fast-opening, the dead zone of the fast-opening system is put forward. To overcome the defect, different operation modes are adopted for different zones. The result shows that with the increase of the valve diameter, the regulating time in the dead zone significantly exceeds the fast-opening time in the whole journey. Accordingly, the optimization operation tactic in the dead zone and the qualification conditions are brought forward. The fast-opening system composed of 32 mm cartridge valves is taken as an example with use of the tactic. The simulation result shows that the maximum regulating time is shortened by 509 ms.

Key words: Steam turbine, Fast-opening, Regulating system, AMESIM
doi:10.1631/jzus.A0720017             CLC number: TK263.7

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