Lecture-26-27-28-29
State Space Canonical forms
Dr. Imtiaz Hussain email: imtiaz.hussain@faculty.muet.edu.pk
URL : http://imtiazhussainkalwar.weebly.com/
– Canonical forms of State Space Models
• Phase Variable Canonical Form
• Controllable Canonical form
• Observable Canonical form
– Similarity Transformations
• Transformation of coordinates
– Transformation to CCF
– Transformation OCF
• Canonical forms are the standard forms of state space models.
• Each of these canonical form has specific advantages which makes it convenient for use in particular design technique.
• There are four canonical forms of state space models
– Phase variable canonical form
– Controllable Canonical form
– Observable Canonical form
– Diagonal Canonical form
– Jordan Canonical Form
Companion forms
Modal forms
• It is interesting to note that the dynamics properties of system remain unchanged whichever the type of representation is used.
• The method of phase variables possess mathematical advantage over other representations.
• This type of representation can be obtained directly from differential equations.
• Decomposition of transfer function also yields Phase variable form.
Phase Variable Canonical form
• Consider an n th order linear plant model described by the differential equation π π π¦ ππ‘ π
+ π
1 π π−1 π¦ ππ‘ π−1
+ β― + π π−1 ππ¦ ππ‘
+ π π π¦ = π’(π‘)
• Where y(t) is the plant output and u(t) is the plant input.
• A state model for this system is not unique but depends on the choice of a set of state variables.
• A useful set of state variables, referred to as phase variables , is defined as: π₯
1
= π¦, π₯
2
= π¦, π₯
3
= β― , π₯ π
= π π−1 π¦ ππ‘ π−1
Phase Variable Canonical form π₯
1
= π¦, π₯
2
= π¦, π₯
3
= β― , π₯ π
= π π−1 π¦ ππ‘ π−1
• Taking derivatives of the first n-1 state variables, we have
π₯
1
= π₯
2
, π₯
2
= π₯
3
, π₯
3
= π₯
4
β― , π₯ π−1
= π₯ π
π₯ π
= −π π π₯
1
− π π−1 π₯
2
− β― − π
1 π₯ π
+ π’(π‘)
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ο¦
1
2 x ο¦ n
ο
1 x ο¦
ο n
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ο
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0
0
ο
0 a n
1
0
ο
0
ο a n
ο
1
0
1
ο
0
ο a n
ο
3
ο
ο
ο
ο
ο ο
0
0
ο
1 a
1
οΉ
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ο« x x n
ο
1 x x
ο
1
2 n
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ο»
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0
οͺ
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0
ο
οͺ
ο«
0
1
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ο»
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οΊ
οΊ u
Phase Variable Canonical form π₯
1
= π¦, π₯
2
= π¦, π₯
3
= β― , π₯ π
= π π−1 π¦ ππ‘ π−1
• Output equation is simply y
ο½
ο
1 0 ο 0 0
ο
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ο« x
1 x
2
ο x n
ο
1 x n
οΉ
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οΊ
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u ( t )
οΌ y
( n
ο
1 ) ο½ x n y
( n )
∫
οΌ
ο a
1
∫
ο a
2
∫ y ( n
ο
2 )
ο½ x n
ο
1
ο
ο a n
… y
ο’ ο½ x
2
∫ y
ο½ x
1
8
u 1 x ο¦ n
1 ο¦ n
ο
1 s
1 s x ο¦ n
ο
2
1 s
ο ο‘
1
ο ο‘
2
ο ο‘
3
ο
ο ο‘ n
ο
1
ο
ο¦
1
ο½ x
2
1 s
ο ο‘ n x
1
1 y
9
Phase Variable Canonical form (Example-1)
• Obtain the state equation in phase variable form for the following differential equation, where u(t) is input and y(t) is output.
2 π 3 π¦ ππ‘ 3
+ 4 π 2 π¦ ππ‘ 2
+ 6 ππ¦ ππ‘
+ 8π¦ = 10π’(π‘)
• The differential equation is third order, thus there are three state variables: π₯
1
= π¦ π₯
2
= π¦ π₯
3
= π¦
• And their derivatives are (i.e state equations)
π₯
1
= π₯
2
π₯
2
= π₯
3
π₯
3
= −4π₯
1
− 3π₯
2
− 2π₯
3
+ 5π’(π‘)
Phase Variable Canonical form (Example-1)
π₯
1
= π₯
2
π₯
2
= π₯
3
π₯
3
= −4π₯
1
− 3π₯
2
− 2π₯
3
+ 5π’(π‘)
• In vector matrix form π₯
1
= π¦ π₯
2
= π¦ π₯
3
= π¦
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2 x
3
1
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ο
0
0
4 y ( t )
ο½
ο
1 0
1
0
ο
3
0
ο
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1 x
2 x
3
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ο
0
1
2
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2 x
1
3
οΊ
ο»
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ο«
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οͺ
0
οͺ
ο«
0
5
οΊ
ο»
οΉ
οΊ u ( t )
Home Work: Draw Sate diagram
Phase Variable Canonical form (Example-2)
• Consider the transfer function of a third-order system where the numerator degree is lower than that of the denominator.
π(π )
π(π )
= π π π 2 + π
1 π + π
2 π 3 + π
1 π 2 + π
2 π + π
3
• Transfer function can be decomposed into cascade form
π(π )
π(π ) 1 π 3 + π
1 π 2 + π
2 π + π
3 π π π 2 + π
1 π + π
2
π(π )
• Denoting the output of the first block as W(s) , we have the following input/output relationships:
π(π )
=
π(π )
1 π 3 + π
1 π 2 + π
2 π + π
3
π(π )
π(π )
= π π π 2 + π
1 π + π
2
Phase Variable Canonical form (Example-2)
π(π )
=
π(π )
1 π 3 + π
1 π 2 + π
2 π + π
3
π(π )
π(π )
= π π π 2 + π
1 π + π
2
• Re-arranging above equation yields π 3 π π = −π
1 π 2 π π − π
2 π π π − π
3
π(π ) + π(π )
π(π ) = π π π 2 π(π ) + π
1 π π(π ) + π
2
π(π )
• Taking inverse Laplace transform of above equations.
π€ π‘ = −π
1 π€ π‘ − π
2 π€ π‘ − π
3 π€(π‘) + u(π‘) π¦(π‘) = π π π€ π‘ + π
1 π€ π‘ + π
2 π€(π‘)
• Choosing the state variables in phase variable form π₯
1
= π€ π₯
2
= π₯
3
Phase Variable Canonical form (Example-1)
• State Equations are given as
π₯
1
= π₯
2
π₯
2
= π₯
3
π₯
3
= −π
3 π₯
1
− π
2 π₯
2
− π
1 π₯
3
+ π’(π‘)
• And the output equation is π¦(π‘) = π
2 π₯
1
+ π
1 π₯
2
+ π π π₯
3 π π π
1 π
2 π
1 π
2 π
3
Phase Variable Canonical form (Example-1)
• State Equations are given as
π₯
1
= π₯
2
π₯
2
= π₯
3
π₯
3
= −π
3 π₯
1
− π
2 π₯
2
− π
1 π₯
3
+ π’(π‘)
• And the output equation is π¦(π‘) = π
2 π₯
1
+ π
1 π₯
2
+ π π π₯
3
−π
1
−π
2
−π
3 π π π
1 π
2
Phase Variable Canonical form (Example-1)
• State Equations are given as
π₯
1
= π₯
2
π₯
2
= π₯
3
π₯
3
= −π
3 π₯
1
− π
2 π₯
2
− π
1 π₯
3
+ π’(π‘)
• And the output equation is π¦(π‘) = π
2 π₯
1
+ π
1 π₯
2
+ π π π₯
3
• In vector matrix form
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2 x
1
3
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ο
0
0 a
3 y ( t )
ο½
ο b
2 b
1
1
0
ο a
2 b o
ο
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οͺ x
1 x
2 x
3
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ο
0
1 a
1
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2 x
1
3
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ο« 1
0
0
οΉ
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ο» u ( t )
Companion Forms
• Consider a system defined by n y
ο« a
1 n y
ο
1
ο« ο ο« a n
ο
1 y ο¦ ο« a n y
ο½ b o n u
ο« b
1 n u
ο
1
ο« ο ο« b n
ο
1 u ο¦ ο« b n u
• where u is the input and y is the output.
• This equation can also be written as
π(π )
π(π )
= π π π π + π
1 π π−1 + β― + π π−1 π + π π π π + π
1 π π−1 + β― + π π−1 π + π π
• We will present state-space representations of the system defined by above equations in controllable canonical form and observable canonical form.
Controllable Canonical Form
π(π )
π(π )
= π π π π + π
1 π π−1 + β― + π π−1 π + π π π π + π
1 π π−1 + β― + π π−1 π + π π
• The following state-space representation is called a controllable canonical form:
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ο« x ο¦
2 x ο¦ n
ο
1 x ο¦ x ο¦
ο
1 n
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ο½
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ο«
ο
0
0
ο
0 a n
1
0
ο
0
ο a n
ο
1
0
1
ο
0
ο a n
ο
2
ο
ο
ο
ο
ο ο
0
0
ο
1 a
1
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ο« x x
1
2 x n
ο
1 x
ο n
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0
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οͺ 0
οΊ
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ο
0
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ο» u
Controllable Canonical Form
π(π )
π(π )
= π π π π + π
1 π π−1 + β― + π π−1 π + π π π π + π
1 π π−1 + β― + π π−1 π + π π y
ο½
ο b n
ο a n b o b n
ο
1
ο a n
ο
1 b o
ο b
2
ο a
2 b o b
1
ο a
1 b o
ο
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1 x
2
ο x n
ο
1 x n
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ο« b o u
Controllable Canonical Form u ( t )
οΌ v
( n )
∫
οΌ
ο ο‘
1
∫ ∫
ο ο‘
2
ο
ο ο‘ n
… v
ο’ ο½ x
2
∫ v
ο½ x
1 d dt
ο d dt d dt
…
ο’ n
ο’ n
ο
1
ο’
1
οΌ
Controllable Canonical Form (Example)
π(π )
π(π )
= π + 3 π 2 + 3π + 2
• Let us Rewrite the given transfer function in following form
π(π )
π(π )
=
0π 2 + π + 3 π 2 + 3π + 2 a
2
ο½
2 a
1
ο½
3 b
2
ο½
3 b
1
ο½
1 b o
ο½
0
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οͺ x ο¦ x ο¦
2
1
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ο½
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οͺ
ο
0 a
2
ο
1 a
1
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οͺ x x
2
1
οΉ
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οͺ
0
1
οΉ
οΊ u
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οͺ x ο¦ x ο¦
2
1
οΉ
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οͺ
ο
0
2
ο
1
3
οΉ
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οͺ x x
2
1
οΉ
οΊ
ο«
ο©
οͺ
1
0
οΉ
οΊ u
Controllable Canonical Form (Example)
π(π )
π(π )
=
0π 2 + π + 3 π 2 + 3π + 2 a
2
ο½
2 a
1
ο½
3 b
2
ο½
3 b
1
ο½
1 b o
ο½
0 y
ο½
ο b
2
ο a
2 b o b
1
ο a
1 b o
ο
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οͺ x x
1
2
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ο« b o u y
ο½
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οͺ x x
2
1
οΉ
οΊ
Controllable Canonical Form (Example)
π(π )
π(π )
= π + 3 π 2 + 3π + 2
• By direct decomposition of transfer function
Y
U
( s
( s
)
)
ο½ s
2 s
ο«
ο«
3 s
3
ο«
2
ο s
ο
2
P ( s ) s
ο
2
P ( s )
Y ( s )
U ( s )
ο½
P ( s ) s
ο
1
ο«
P ( s )
ο«
3
3 s
ο
1
P ( s ) s
ο
2
ο«
P ( s )
2 s
ο
2
P ( s )
• Equating Y(s) with numerator on the right hand side and U(s) with denominator on right hand side.
Y ( s )
ο½ s
ο
1
P ( s )
ο«
3 s
ο
2
P ( s ).........
.......( 1 )
U ( s )
ο½
P ( s )
ο«
3 s
ο
1
P ( s )
ο«
2 s
ο
2
P ( s ).........
.......( 2 )
Controllable Canonical Form (Example)
• Rearranging equation-2 yields
P ( s )
ο½
U ( s )
ο
3 s
ο
1
P ( s )
ο
2 s
ο
2
P ( s ).........
.......( 3 )
• Draw a simulation diagram using equations (1) and (3)
P ( s )
ο½
U ( s )
ο
3 s
ο
1
P ( s )
ο
2 s
ο
2
P ( s ) Y ( s )
ο½ s
ο
1
P ( s )
ο«
3 s
ο
2
P ( s )
U(s)
-2
P(s)
ο¦
2
-3
1/s x
2
ο½ x ο¦
1
1/s
1 x
1
3
Y(s)
Controllable Canonical Form (Example)
-2
U(s)
P(s)
ο¦
2
-3
1/s x
2
ο½ ο¦ x
1
1/s x
1
3
Y(s)
1
• State equations and output equation are obtained from simulation diagram.
x ο¦
1
ο½ x
2
ο¦
2
ο½
U ( s )
ο
3 x
2
ο
2 x
1
Y ( s )
ο½
3 x
1
ο« x
2
Controllable Canonical Form (Example) x ο¦
1
ο½ x
2
ο¦
2
ο½
U ( s )
ο
3 x
2
ο
2 x
1
Y ( s )
ο½
3 x
1
ο« x
2
• In vector Matrix form
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2
1
οΉ
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ο½
ο©
οͺ
ο
0
2
ο
1
3
οΉ
ο»
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οͺ x x
2
1
οΉ
οΊ
ο«
ο©
ο«
0
1
οΉ
ο» f ( t ) y
ο½
ο
3 1
ο
ο©
οͺ x
1 x
2
οΉ
οΊ
Observable Canonical Form
π(π )
π(π )
= π π π π + π
1 π π−1 + β― + π π−1 π + π π π π + π
1 π π−1 + β― + π π−1 π + π π
• The following state-space representation is called an observable canonical form:
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οͺ
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ο« x x ο¦ n
ο
1 x ο¦
ο¦ x ο¦
ο
1
2 n
οΉ
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οΊ
οΊ
ο»
ο½
ο©
0
οͺ
οͺ
οͺ
οͺ
1
ο
οͺ
ο«
0
0
0
0
ο
0
0
ο
ο
ο
ο
ο
0
0
ο
0
1
ο
ο
ο
ο n a n
ο
1
ο a a a
2
1
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ο« x x
1
2 x n
ο
1 x
ο n
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ο«
οͺ
ο«
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οͺ
οͺ
οͺ b n b n
ο
1 b
2 b
1
ο
ο
ο
ο
ο a n b o a n
ο
1 b o a a
2
1 b b o o
οΉ
οΊ
οΊ
οΊ
οΊ
οΊ
ο» u
Observable Canonical Form
π(π )
π(π )
= π π π π + π
1 π π−1 + β― + π π−1 π + π π π π + π
1 π π−1 + β― + π π−1 π + π π y
ο½
ο
0 0 ο 0 1
ο
ο©
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οͺ
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ο« x
1 x
2
ο x n
ο
1 x n
οΉ
οΊ
οΊ
οΊ
οΊ
οΊ
ο»
ο« b o u
Observable Canonical Form (Example)
π(π )
π(π )
= π + 3 π 2 + 3π + 2
• Let us Rewrite the given transfer function in following form
π(π )
π(π )
=
0π 2 + π + 3 π 2 + 3π + 2 a
2
ο½
2 a
1
ο½
3 b
2
ο½
3 b
1
ο½
1 b o
ο½
0
ο©
οͺ x ο¦ x ο¦
2
1
οΉ
οΊ
ο½
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οͺ
0
1
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οͺ x ο¦ x ο¦
2
1
οΉ
οΊ
ο½
ο©
οͺ
0
1
ο
ο a
2 a
1
οΉ
οΊ
ο©
οͺ x x
2
1
οΉ
οΊ
ο«
ο©
ο« b b
2
1
ο
ο a
2 b o a
1 b o
οΉ
οΊ u
ο
ο
2
3
οΉ
οΊ
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οͺ x x
2
1
οΉ
οΊ
ο«
ο©
οͺ
3
οΉ
1
οΊ u
Observable Canonical Form (Example)
π(π )
π(π )
=
0π 2 + π + 3 π 2 + 3π + 2 a
2
ο½
2 a
1
ο½
3 b
2
ο½
3 b
1
ο½
1 b o
ο½
0 y
ο½
ο
0 1
ο
ο©
οͺ x
1 x
2
οΉ
οΊ
ο« b o u y
ο½
ο
0 1
ο
ο©
οͺ x
1 x
2
οΉ
οΊ
• It is desirable to have a means of transforming one state-space representation into another.
• This is achieved using so-called similarity transformations.
• Consider state space model x ο¦ ( t )
ο½
Ax ( t )
ο«
Bu ( t ) y ( t )
ο½
Cx ( t )
ο«
Du ( t )
• Along with this, consider another state space model of the same plant x
ο¦
( t )
ο½
A x ( t )
ο«
B u ( t ) y ( t )
ο½
C x ( t )
ο«
D u ( t )
• Here the state vector π₯ , say, represents the physical state relative to some other reference, or even a mathematical coordinate vector.
• When one set of coordinates are transformed into another set of coordinates of the same dimension using an algebraic coordinate transformation, such transformation is known as similarity transformation.
• In mathematical form the change of variables is written as, x ( t )
ο½
T x ( t )
• Where T is a nonsingular nxn transformation matrix.
• The transformed state π₯(π‘) is written as x ( t )
ο½
T
ο
1 x ( t )
• The transformed state π₯(π‘) is written as x ( t )
ο½
T
ο
1 x ( t )
• Taking time derivative of above equation x
ο¦
( t )
ο½
T
ο
1 x ο¦ (t) x
ο¦
( t )
ο½
T
ο
1
ο
Ax ( t )
ο«
Bu ( t )
ο
( t )
ο½
T
ο
1
ο
AT x ( t )
ο«
Bu ( t )
ο x ο¦ ( t )
ο½
Ax ( t )
ο«
Bu ( t ) x ( t )
ο½
T x ( t )
( t )
ο½
T
ο
1
AT x ( t )
ο«
T
ο
1
Bu ( t )
( t )
ο½
A x ( t )
ο«
B u ( t )
A
ο½
T
ο
1
AT B
ο½
T
ο
1
B
• Consider transformed output equation y ( t )
ο½
C x ( t )
ο«
D u ( t )
• Substituting π₯ π‘ = π −1 π₯(π‘) in above equation y ( t )
ο½
C T
ο
1 x ( t )
ο«
D u ( t )
• Since output of the system remain unchanged [i.e.
π¦ π‘ = π¦(π‘) ] therefore above equation is compared with π¦ π‘ =
πΆπ₯ π‘ + π·π’(π‘) that yields
C
ο½
CT D
ο½
D
• Following relations are used to preform transformation of coordinates algebraically
A
ο½
T
ο
1
AT B
ο½
T
ο
1
B
C
ο½
CT D
ο½
D
• Invariance of Eigen Values sI
ο
A
ο½ sI
ο
T
ο
1
AT
ο½ sT
ο
1
T
ο
T
ο
1
AT
ο
T
ο
1
T
ο½
I
ο½
T
ο
1 sI
ο
A T
ο½ sI
ο
A sI
ο
A
ο½ sI
ο
A
Transformation to CCF
• Transformation to CCf is done by means of transformation matrix
P .
P
ο½
CM
ο΄
W
• Where CM is controllability Matrix and is given as
πΆπ = π΅ π΄π΅ β― π΄ π−1 π΅ and W is coefficient matrix
W
ο½
ο©
οͺ
οͺ
οͺ
οͺ
οͺ
ο« a a n
ο
1 n
ο
2
ο a
1
1 a n
ο
2 a n
ο
3
ο
1
0
ο
ο
ο
ο
ο a
1
1
ο
0
0
1
0
ο
0
0
οΉ
οΊ
οΊ
οΊ
οΊ
οΊ
ο»
Where the a i
’s are coefficients of the characteristic polynomial π πΌ − π΄ = π π
+ π
1 π π−1
+ π
2 π π−2
+ β― + π π−1 s+ π π
Transformation to CCF
• Once the transformation matrix P is computed following relations are used to calculate transformed matrices.
A
ο½
P
ο
1
AP B
ο½
P
ο
1
B C
ο½
CP D
ο½
D
Transformation to CCF ( Example )
• Consider the state space system given below.
π₯
1 π₯
2 π₯
3
=
1 2 1
0 1 3
1 1 1 π₯
1 π₯
2 π₯
3
+
1
0
1 π’(π‘)
• Transform the given system in CCF.
Transformation to CCF ( Example ) π₯
1 π₯
2 π₯
3
=
1 2 1
0 1 3
1 1 1 π₯
1 π₯
2 π₯
3
+
1
0
1
• The characteristic equation of the system is π’(π‘) π πΌ − π΄ = π − 1 −2 −1
0 π − 1 −3
−1 −1 π − 1
= π 3 − 3π 2 − π − 3 π
1
= −3,
W
ο½
οͺ
ο«
ο©
οͺ a
2 a
1
1 a
1
1
0 π
2
= −1,
1
0
0
οΊ
ο»
οΉ
οΊ
ο½
οͺ
ο«
ο©
οͺ
ο
ο
1
1
3 π
3
= −1
ο
3
1
0
1
0
0
οΊ
ο»
οΉ
οΊ
Transformation to CCF ( Example ) π₯
1 π₯
2 π₯
3
=
1 2 1
0 1 3
1 1 1 π₯
1 π₯
2 π₯
3
+
1
0
1 π’(π‘)
• Now the controllability matrix CM is calculated as
πΆπ = π΅ π΄π΅ π΄ 2 π΅
πΆπ =
1 2 10
0 3 9
1 2 7
• Transformation matrix P is now obtained as
π = πΆπ × π =
1 2 10
0 3 9
1 2 7
−1 −3 1
−3 1 0
1 0 0
π =
3 −1 1
0 3 0
0 −1 1
Transformation to CCF ( Example )
• Using the following relationships given state space representation is transformed into CCf as
A
ο½
P
ο
1
AP B
ο½
P
ο
1
B
A
ο½
P
ο
1
AP
ο½
ο©
οͺ
0
οͺ
ο«
0
3
1
0
1
B
ο½
P
ο
1
B
ο½
ο©
οͺ
οͺ
ο«
0
0
1
οΉ
οΊ
οΊ
ο»
0
1
3
οΉ
οΊ
οΊ
ο» π πΌ − π΄ = π 3 − 3π 2 − π − 3
Transformation to OCF
• Transformation to CCf is done by means of transformation matrix
Q .
Q
ο½
( W
ο΄
OM )
ο
1
• Where OM is observability Matrix and is given as
ππ = πΆ πΆπ΄ β― πΆπ΄ π−1 π and W is coefficient matrix
W
ο½
ο©
οͺ
οͺ
οͺ
οͺ
οͺ
ο« a a n
ο
1 n
ο
2
ο a
1
1 a n
ο
2 a n
ο
3
ο
1
0
ο
ο
ο
ο
ο a
1
1
ο
0
0
1
0
ο
0
0
οΉ
οΊ
οΊ
οΊ
οΊ
οΊ
ο»
Where the a i
’s are coefficients of the characteristic polynomial π πΌ − π΄ = π π
+ π
1 π π−1
+ π
2 π π−2
+ β― + π π−1 s+ π π
Transformation to OCF
• Once the transformation matrix Q is computed following relations are used to calculate transformed matrices.
A
ο½
Q
ο
1
AQ B
ο½
Q
ο
1
B C
ο½
CQ D
ο½
D
Transformation to OCF ( Example )
• Consider the state space system given below.
π₯
1 π₯
2 π₯
3
=
1 2 1
0 1 3
1 1 1 π₯
1 π₯
2 π₯
3
+ π¦(π‘) = 1 1 0
• Transform the given system in OCF.
π₯
1 π₯
2 π₯
3
1
0
1 π’(π‘)
Transformation to OCF ( Example ) π₯
1 π₯
2 π₯
3
=
1 2 1
0 1 3
1 1 1 π₯
1 π₯
2 π₯
3
+
1
0
1
• The characteristic equation of the system is π’(π‘) π πΌ − π΄ = π − 1 −2 −1
0 π − 1 −3
−1 −1 π − 1
= π 3 − 3π 2 − π − 3 π
1
= −3,
W
ο½
οͺ
ο«
ο©
οͺ a
2 a
1
1 a
1
1
0 π
2
= −1,
1
0
0
οΊ
ο»
οΉ
οΊ
ο½
οͺ
ο«
ο©
οͺ
ο
ο
1
1
3 π
3
= −1
ο
3
1
0
1
0
0
οΊ
ο»
οΉ
οΊ
Transformation to OCF ( Example ) π₯
1 π₯
2 π₯
3
=
1 2 1
0 1 3
1 1 1 π₯
1 π₯
2 π₯
3
+
1
0
1 π’(π‘) π¦(π‘) = 1 1 0
• Now the observability matrix OM is calculated as π₯
1 π₯
2 π₯
3
ππ = πΆ πΆπ΄ πΆπ΄ 2 π
ππ =
1 1 0
1 3 4
5 6 10
• Transformation matrix Q is now obtained as
π = π × ππ −1 =
0.333
−0.166
0.333
−0.333
0.166
0.666
0.166
0.166
0.166
Transformation to CCF ( Example )
• Using the following relationships given state space representation is transformed into CCf as
A
ο½
Q
ο
1
AQ B
ο½
Q
ο
1
B C
ο½
CQ D
ο½
D
A
ο½
Q
ο
1
AQ
ο½
ο©
οͺ
0
οͺ
ο«
1
0
0
0
1
3
οΉ
οΊ
1
3
οΊ
ο»
B
ο½
Q
ο
1
B
ο½
οͺ
ο«
ο©
οͺ
3
2
1
οΊ
ο»
οΉ
οΊ
C
ο½
CQ
ο½
ο
0 0 1
ο
• Obtain state space representation of following transfer function in Phase variable canonical form, OCF and CCF by
– Direct Decomposition of Transfer Function
– Similarity Transformation
– Direct Approach
π(π )
π(π )
= π 2 + 2π + 3 π 3 + 5π 2 + 3π + 2
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END OF LECTURES-26-27-28-29