Skip to main content

Advertisement

Log in

The parameter identification method of steam turbine nonlinear servo system based on artificial neural network

  • Technical Paper
  • Published:
Journal of the Brazilian Society of Mechanical Sciences and Engineering Aims and scope Submit manuscript

Abstract

The servo system in steam turbine digital electric-hydraulic control system (DEH) is affected by nonlinear factors when it is working. To accurately simulate dynamic characteristics of the DEH, a new nonlinear servo system is proposed, which has limit, dead zone and correction coefficient caused by unknown factors. The model parameters are divided into linear parameters and nonlinear parameters to be identified, respectively. Neural networks are used to identify linear parameters. The nonlinear parameters should be identified according to flow characteristic curve. To verify the validity of the proposed model and parameter identification method, the actual data of primary frequency control from a 1000 MW Ultra Supercritical Unit is adopted. Meanwhile, the linear model with no nonlinear factors is used for comparison. Where the fitting degree of valve opening is 98.445% and power is 96.986%, the output of nonlinear model coincides with actual output well. Where the relative error of stable result is 5% of valve opening and 1.58% of power, the error of linear model is larger. The simulation results of the proposed method show that the nonlinear factors of high-power units cannot be ignored and the nonlinear model of servo system is more accurate.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13

Similar content being viewed by others

Abbreviations

ANN:

Artificial neural network

BP:

Back propagation

DEH:

Digital electric-hydraulic control system

GA:

Genetic algorithm

NN:

Neural network

PFC:

Primary frequency control

PSO:

Particle swarm optimization

RBF:

Radial basis function

UHV:

Ultra-high voltage

UHVTT:

Ultra-high voltage transmission technology

d 1 :

Artificial neural network

d 2 :

Back propagation

f t :

Digital electric-hydraulic control system

f z :

Genetic algorithm

l 1 :

Neural network

k 2 :

Primary frequency control

l 1 :

Particle swarm optimization

l 2 :

Radial basis function

n :

Ultra-high voltage

s :

Ultra-high voltage transmission technology

T :

Primary frequency control

T y :

Particle swarm optimization

T c :

Radial basis function

x :

Ultra-high voltage

x min :

Ultra-high voltage transmission technology

x max :

Ultra-high voltage transmission technology

x* :

Ultra-high voltage transmission technology

τ :

Time constant of delay rate(s)

γ :

Parameter vector

α :

Output number of neural network

β :

Input number of neural network

References

  1. Fu ZG, Jin T, Zhou LJ, Ge ZH, Zheng L, Yang YP (2009) Research and application of the reversed modeling method and partial least-square regression modeling for the complex thermal system. Proc CSEE 29(2):25–29 (in chinese)

    Google Scholar 

  2. Wang ZQ, Zhu SZ, Lou HX, Sheng SD, Zhang LY (2003) PLPF based modeling and parameter identifying of large steam turbine in time domain. Proc CSEE 23:128–133 (in chinese)

    Google Scholar 

  3. Zhu Y, Jiang WL, Kong XD, Zheng Z (2015) Study on nonlinear dynamics characteristics of electrohydraulic servo system. Nonlinear Dyn 80:723–737

    Article  Google Scholar 

  4. Guan C, Pan S (2008) Adaptive sliding mode control of electro-hydraulic system with nonlinear unknown parameters. Control Eng Prac 16:1275–1284

    Article  Google Scholar 

  5. Li W, Zheng ZJ, Sheng DR, Cheng JH, Ren HR (2008) Recursive least square method based parameter identification of steam turbine digital electric-hydraulic governing system. J Zhejiang Univ (Eng Sci) 42:1761–1764

    Google Scholar 

  6. Hiyama T, Suzuki N, Karino H, Kwang Yun L, Andou H (1999) Artificial neural network based modeling of governor-turbine system. In: IEEE Power Engineering Society. Winter Meeting (Cat. No. 99CH36233) 1:129–133

  7. Rashtchi V, Rahimpour E, Rezapour EM (2006) Using a genetic algorithm for parameter identification of transformer R-L-C-M model. Electr Eng 88:417–422

    Article  Google Scholar 

  8. Rahimpour E, Rashtchi V, Pesaran M (2007) Parameter identification of deep-bar induction motors using genetic algorithm. Electr Eng 89:547–552

    Article  Google Scholar 

  9. Li Q, Chen W, Wang Y, Liu S (2011) Parameter identification for PEM fuel-cell mechanism model based on effective informed adaptive particle swarm optimization. IEEE Trans Industr Electron 58:2410–2419

    Article  Google Scholar 

  10. Liu W, Liu L, Chung IY, Cartes DA (2011) Real-time particle swarm optimization based parameter identification applied to permanent magnet synchronous machine. Appl Soft Comp 11:2556–2564

    Article  Google Scholar 

  11. Johnson W, Gupta NK (2015) Instrumental variables algorithm for modal parameter identification in flutter testing. AIAA J 16:800–806

    Article  MATH  Google Scholar 

  12. Tóth R, Laurain V, Gilson M, Garnier H (2012) Instrumental variable scheme for closed-loop LPV model identification ☆. Automatica 48:2314–2320

    Article  MathSciNet  MATH  Google Scholar 

  13. Janot A, Vandanjon PO, Gautier M (2013) Identification of physical parameters and instrumental variables validation with two-stage least squares estimator. IEEE Trans Control Syst Technol 21:1386–1393

    Article  Google Scholar 

  14. Zahid T, Li W (2016) A comparative study based on the least square parameter identification method for state of charge estimation of a LiFePO4 battery pack using three model-based algorithms for electric vehicles. Energies 9:720

    Article  Google Scholar 

  15. Yang T, Feng Y, Yang T, Ren Y, Tang L, Li Y, (2012) Parameter identification of steam turbine speed governor system. In: 2012 Asia-Pacific Power and Energy Engineering Conference. pp. 1–8

  16. Karayaka HB, Keyhani A, Agrawal BL, Selin DA, Heydt GT (2000) Identification of armature, field, and saturated parameters of a large steam turbine-generator from operating data. IEEE Trans Energy Convers 15:181–187

    Article  Google Scholar 

  17. Levin AU, Narendra KS (1996) Control of nonlinear dynamical systems using neural networks. II. Observability, identification, and control. Trans Neur Netw 7:30–42

    Article  Google Scholar 

  18. Mashor MY (2005) Performance comparison between HMLP, MLP and RBF networks with application to on-line system identification. In Cybernetics and Intelligent Systems, 2004 IEEE Conference on 2005. vol. 1 pp. 643–648

Download references

Acknowledgements

This research was supported by the Electric Power Research Institute of State Grid Corporation of China in Zhejiang province.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Zi-Tao Yu.

Additional information

Technical Editor: Jose A. dos Reis Parise.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Liao, JL., Yin, F., Luo, ZH. et al. The parameter identification method of steam turbine nonlinear servo system based on artificial neural network. J Braz. Soc. Mech. Sci. Eng. 40, 165 (2018). https://doi.org/10.1007/s40430-018-1086-8

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s40430-018-1086-8

Keywords

Navigation