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Control of stochastic distributed-parameter systems

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Abstract

A scheme is proposed for the feedback control of distributed-parameter systems with unknown boundary and volume disturbances and observation errors. The scheme consists of employing a nonlinear filter in the control loop such that the controller uses the optimal estimates of the state of the system. A theoretical comparison of feedback proportional control of a styrene polymerization reactor with and without filtering is presented. It is indicated how an approximate filter can be constructed, greatly reducing the amount of computing required.

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Abbreviations

a(t):

l-vector noisy dynamic input to system

A(t, a):

l-vector function

A′:

frequency factor for first-order rate law (5.68×106 sec−1)

b :

distance to the centerline between two coil banks in the reactor (4.7 cm)

B :

k-vector function defining the control action

c(χ, τ):

concentration of styrene monomer, molel −1

C p :

heat capacity (0.43 cal · g−1 · K−1)

C ij :

constants in approximate filter, Eqs. (49)–(52)

E :

activation energy (20330 cal · mole−1)

:

expectation operator

f(t,...):

n-vector function

g 0,g 1(t,...):

n-vector functions

h(t, u):

m-vector function relating observations to states

H(t):

function defined in Eq. (36)

k :

dimensionality of control vectorv(x, t)

k i :

constants in approximate filter, Eqs. (49)–(52)

K :

dimensionless proportional gain

l :

dimensionality of dynamic inputa(t)

m :

dimensionality of observation vectory(t)

n :

dimensionality of state vectoru(x, t)

P (vv)(x, s, t):

n×n matrix governed by Eq. (9)

P (va)(x, t):

n×l matrix governed by Eq. (10)

P (aa)(t):

l×l matrix governed by Eq. (11)

q i (t):

diagonal elements ofm×m matrixQ(x, s, t)

Q(x, s, t):

m×m weighting matrix

R :

universal gas constant (1.987 cal · mole−1 · K−1)

R(x, s, t):

n×n weighting matrix

R i (t):

n×n weighting matrix

s :

dimensionless spatial variable

S(x, s, t):

matrix defined in Eq. (11)

t :

dimensionless time variable

T(χ, τ):

temperature, K

u(x, t):

n-dimensional state vector

u c (t):

wall temperature

u d :

desired value ofu 1(1,t)

u c *:

reference control value ofu c

u max c :

maximum value ofu c

u min c :

minimum value of c

v(x, t):

k-dimensional control vector

W(t):

l×l weighting matrix

x :

dimensionless spatial variable

y(t):

m-dimensional observation vector

α i :

constants in approximate filter, Eqs. (49)–(52)

β :

dimensionless parameter defined in Eq. (29)

ΔH :

heat of reaction (17500 cal · mole−1)

ε :

dimensionless activation energy, defined in Eq. (29)

δ(x):

Dirac delta function

η(x, t):

m-dimensional observation noise

κ :

thermal conductivity (0.43×10−3 cal · cm−1 · sec−1 · K−1)

ρ :

density (1 g · cm−3)

τ :

time, sec

φ :

dimensionless parameter defined in Eq. (29)

χ :

spatial variable, cm

*:

reference value

^:

estimated value

References

  1. Sworder, D.,Optimal Adaptive Control Systems, Academic Press, New York, 1966.

    Google Scholar 

  2. Aoki, M.,Optimization of Stochastic Systems, Academic Press, New York, 1967.

    Google Scholar 

  3. Kusher, H. J.,Stochastic Stability and Control, Academic Press, New York, 1969.

    Google Scholar 

  4. Åström, K.,Introduction to Stochastic Control Theory, Academic Press, New York, 1970.

    Google Scholar 

  5. Tzafestas, S. G., andNightingale, J. M.,Optimal Control of a Class of Linear Stochastic Distributed-Parameter Systems, Proceedings of the Institution of Electrical Engineers, Vol. 115, No. 8, 1968.

  6. Kushner, H. J.,On the Optimal Control of a System Governed by a Linear Parabolic Equation with White Noise Inputs, SIAM Journal on Control, Vol. 6, No. 4, 1968.

  7. Thau, F. E.,Optimum Control of a Class of Randomly Excited Distributed-Parameter Systems, Proceedings of the Fourth IFAC Congress, Warsaw, Poland, 1969.

  8. Pell, T. M., Jr., andAris, R.,Some Problems in Chemical Reactor Analysis with Stochastic Features: II, Control of Linearized Distributed Systems on Discrete and Corrupted Observations, Industrial and Engineering Chemistry Fundamentals, Vol. 9, No. 1, 1970.

  9. Sholar, M. S., andWiberg, D. M.,Canonical Equations for Boundary Feedback Control of Stochastic Distributed-Parameter Systems, Automatica, Vol. 8, No. 3, 1972.

  10. Seinfeld, J. H.,Gavalas, G. R., andHwang, M.,Control of Nonlinear Stochastic Systems, Industrial and Engineering Chemistry Fundamentals, Vol. 8, No. 2, 1969.

  11. Balakrishnan, A. V., andLions, J. L.,State Estimation for Infinite Dimensional Systems, Journal of Computer and System Science, Vol. 1, No. 4, 1967.

  12. Falb, P. L.,Infinite-Dimensional Filtering: The Kalman-Bucy Filter in Hilbert Space, Information and Control, Vol. 11, No. 1, 1967.

  13. Meditch, J. S.,On State Estimation for Distributed-Parameter Systems, Journal of the Franklin Institute, Vol. 290, No. 1, 1970.

  14. Thau, F. E.,On Optimal Filtering for A Class of Linear Distributed-Parameter Systems, Journal of Basic Engineering, Vol. 91, No. 2, 1969.

  15. Tzafestas, S. G., andNightingale, J. M.,Optimal Filtering, Smoothing, and Prediction in Linear Distributed-Parameter Systems, Proceedings of the Institution of Electrical Engineers, Vol. 115, No. 8, 1968.

  16. Tzafestas, S. G., andNightingale, J. M.,Moment Equations for Stochastic Distributed-Parameter Processes, Electronics Letters, Vol. 6, No. 3, 1970.

  17. Kusher, H. J.,Filtering for Linear Distributed-Parameter Systems, SIAM Journal on Control, Vol. 8, No. 3, 1970.

  18. Tzafestas, S. G., andNightingale, J. M.,Maximum-Likelihood Approach to the Optimal Filtering of Distributed Parameter Systems, Proceedings of the Institution of Electrical Engineers, Vol. 116, No. 6, 1969.

  19. Seinfeld, J. H., Gavalas, G. R., andHwang, M.,Nonlinear Filtering in Distributed-Parameter Systems, Journal of Dynamic Systems, Measurement, and Control, Vol. 93G, No. 3, 1971.

  20. Hwang, M., Seinfeld, J. H., Gavalas, G. R.,Optimal Least-Square Filtering and Interpolation in Distributed Parameter Systems, Journal of Mathematical Analysis and Applications, Vol. 39, No. 1, 1972.

  21. Boundy, R. H., andBoyer, R. F.,Styrene: Its Polymers, Copolymers and Derivatives, Hafner, New York, 1952.

    Google Scholar 

  22. Gee, J., Personal Communication, 1969.

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Communicated by R. Jackson

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Yu, T.K., Seinfeld, J.H. Control of stochastic distributed-parameter systems. J Optim Theory Appl 10, 362–380 (1972). https://doi.org/10.1007/BF00935400

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