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lqry

Form linear-quadratic (LQ) state-feedback regulator with output weighting

Syntax

[K,S,e] = lqry(sys,Q,R,N)

Description

Given the plant

x˙=Ax+Buy=Cx+Du

or its discrete-time counterpart, lqry designs a state-feedback control

u=Kx

that minimizes the quadratic cost function with output weighting

J(u)=0(yTQy+uTRu+2yTNu)dt

(or its discrete-time counterpart). The function lqry is equivalent to lqr or dlqr with weighting matrices:

[Q¯N¯N¯TR¯]=[CT0DTI][QNNTR][CD0I]

[K,S,e] = lqry(sys,Q,R,N) returns the optimal gain matrix K, the Riccati solution S, and the closed-loop eigenvalues e = eig(A-B*K). The state-space model sys specifies the continuous- or discrete-time plant data (A, B, C, D). The default value N=0 is assumed when N is omitted.

Examples

See LQG Design for the x-Axis for an example.

Limitations

The data A,B,Q¯,R¯,N¯ must satisfy the requirements for lqr or dlqr.

Version History

Introduced before R2006a

See Also

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