d q Transormation

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    dq Theory for Synchronous Machinewithout Damper Winding

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    Relevance to Synchronous Machine

    dq means direct and quadrature. Direct axis is aligned withthe rotors pole. Quadrature axis refers to the axis whoseelectrical angle is orthogonal to the electric angle of directaxis.

    a axis

    d axisq axis

    b axis

    c axis

    m a

    d

    mq

    22

    2

    memqr

    mme

    P

    P min g

    max,or r

    min,or r max g

    isr

    d

    a axis

    m a

    q axis

    mq

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    Parks Transformation

    Stator quantities ( S abc) of current, voltage, or flux can beconverted to quantities ( S dq0) referenced to the rotor.

    This conversion comes through the K matrix.

    01

    0

    dqabc

    abcdq

    SK S

    KSS

    13/2sin3/2cos

    13/2sin3/2cos1sincos

    2/12/12/1

    3/2sin3/2sinsin3/2cos3/2coscos

    3

    2

    1

    meme

    meme

    meme

    mememe

    mememe

    K

    K

    13/2cos3/2sin13/2cos3/2sin

    1cossin

    2/12/12/13/2cos3/2coscos

    3/2sin3/2sinsin

    32

    1

    r r

    r r

    r r

    r r r

    r r r

    K

    K

    where

    or

    (MITs notation)

    (Purdues notation)

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    Voltage Equations (1)

    abcabcS abc dt d iR v

    010101 dqdqS dq dt d

    K iK R vK

    010101 dqdqS dq dt d K K iK KR vK K

    01

    01

    01

    0 dqdqdqS dq dt d

    dt d

    K K KK iK KR v

    01

    000 dqdqdqS dq dt d

    dt d

    K K iR v

    100

    010001

    sS RR

    For stator windings

    For field winding:

    f f f f dt d

    i Rv

    Under motor reference convention for currents(i.e. the positive reference direction for currents is into the machine):

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    Voltage Equations (2)

    We derive the derivative of K-1:

    Then, we get

    000

    00

    001

    r

    r

    dt d

    K K

    f f f

    s

    r d qq s

    r qd d s

    f

    q

    d

    dt d i R

    dt d

    i R

    dt d i R

    dt d

    i R

    v

    v

    vv

    000

    03/2sin3/2cos

    03/2sin3/2cos0sincos

    03/2cos3/2sin03/2cos3/2sin0cossin

    1

    r r

    r r

    r r

    r

    meme

    meme

    meme

    me

    dt

    d K

    dt d me

    me

    And for voltage, we get

    2 P

    dt d

    mmer

    r

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    Dynamical Equations for Flux Linkage

    f f f

    s

    r d q sq

    r qd sd

    f

    q

    d

    i Rvi Rv

    i Rv

    i Rv

    dt

    d

    000

    The derivations so far are valid for both linear and nonlinear models.

    f

    q

    d

    dqf

    0

    f f f

    s

    r d q sq

    r qd sd

    i Rv

    i Rv

    i Rv

    i Rv

    00

    V

    Let

    we haveV

    dt

    d dqf

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    Flux Linkage vs. Current (1)

    The next step is to relate current to flux linkage throughinductances. For salient pole rotor, the inductances canbe approximately expressed as

    cf

    bf

    af

    sf

    L

    L

    LL

    32

    2cos

    322cos

    2cos

    me B Alscc

    me B Alsbb

    me B Alsaa

    L L L L

    L L L L

    L L L L

    or:

    32

    2cos

    322cos

    2cos

    r B Alscc

    r B Alsbb

    r B Alsaa

    L L L L

    L L L L

    L L L L

    2

    mer

    f T sf

    sf ssabcf LL

    LLL

    cccbca

    bcbbba

    acabaa

    ss

    L L L

    L L L

    L L LL

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    Flux Linkage vs. Current (2)

    32

    2cos21

    2cos21

    32

    2cos21

    me B Acaac

    me B Acbbc

    me B Abaab

    L L L L

    L L L L

    L L L L

    Note: Higher order harmonics are neglected.

    3

    2cos

    32

    cos

    cos

    me sf fccf

    me sf fbbf

    me sf faaf

    L L L

    L L L

    L L Lor:

    32

    2cos21

    2cos21

    32

    2cos21

    r B Acaac

    r B Acbbc

    r B Abaab

    L L L L

    L L L L

    L L L L

    32

    sin

    32

    sin

    sin

    r sf fccf

    r sf fbbf

    r sf faaf

    L L L

    L L L

    L L L

    2

    mer

    Ref: 1. A. E. Fitzgerald, C. Kingsley, Jr., and S. D. Umans, Electric Machinery,6 th Edition, pages 660-661.

    2. P. C. Krause, O. Wasynczuk, and S. D. Sudhoff, Analysis of Electric Machinery and Drive Systems, 2 nd Edition, page 52.

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    Flux Linkage vs. Current (3)

    This matrix can be transformed into dq0 form and used tofind flux linkage.

    abcf abcf abcf iL

    f sf dq ssdq iLiK L K 01

    01

    dqf dqf dqf iL

    f sf dq ssdq iKLiK KL 01

    0

    f T sf

    sf ss

    abcf LL

    LLL

    f

    abc

    abcf

    f

    abc

    abcf i

    ii

    f sf abc ssabc iLiL

    f f abcT sf f i L iL f f dq

    T sf f i L 0

    1iK L

    f T sf

    sf ssdqf

    L1

    1

    K L

    KLK KLL

    f

    dqdqf

    0

    f

    dqdqf

    i

    0i

    i

    From with

    where

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    Inductance Matrix in dq0 Frame

    f sf

    q

    sf d

    dqf

    L L

    L

    L

    L L

    0023

    000

    000

    00

    0L

    where

    )(23

    )(

    2

    3

    B Amq

    B Amd

    L L L

    L L L

    ls

    mqlsq

    md lsd

    L L

    L L L

    L L L

    0

    and

    dqf dqf dqf iL

    From d sf f f f

    ls

    qqq

    f sf d d d

    i Li L

    i L

    i Li Li L

    23

    00

    Through derivations, we have

    f T sf

    sf ssdqf L1

    1

    K L

    KLK KL

    L

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    Dynamical Equation in terms of Current

    V

    dt

    d dqf For linear model

    from

    VLi

    1dqf

    dqf

    dt

    d dynamical equationin terms of current

    dqf dqf dqf iL

    f f f

    s

    r d q sq

    r qd sd

    i Rv

    i Rv

    i Rv

    i Rv

    00

    V

    and

    where

    qqq

    f sf d d d

    i L

    i Li L

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    Power

    Electrical instantaneous Input Power on Stator can also beexpressed through dq0 theory.

    011

    0 )( dqT T

    dqabcT abcccbbaain iviviv p iK K viv

    00223 iviviv p qqd d in

    200010

    001

    23

    )(11

    K K T

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    Torque

    00223

    iviviv p qqd d in

    000

    dt d

    i Rdt

    d i R

    dt d

    i R

    v

    v

    v

    s

    r d qq s

    r qd d s

    q

    d

    From

    we have

    )(223

    223

    223 0

    020

    22d qqd m

    q

    qd

    d qd sin ii P

    dt d

    idt

    d idt

    d iiii R p

    Copper Loss Mechanical PowerMagnetic Power inWindings

    Therefore, electromagnetic torque on rotor

    )(223

    d qqd m

    meche ii P p

    T

    mech p

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    Equivalent Circuits (1)

    f f f

    s

    r d qq s

    r qd d s

    f

    q

    d

    dt d

    i R

    dt d

    i Rdt

    d i R

    dt d

    i R

    v

    v

    v

    v

    000

    d sf f f f

    ls

    qqq

    f sf d d d

    i Li L

    i L

    i L

    i Li L

    23

    00

    d axisdt

    di L

    dt di

    Li Rv f sf d

    d r qd sd

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    Equivalent Circuits (2)

    q axisdt

    di Li Rv qqr d q sq

    0 axisdt di

    Li Rv s0

    000

    This circuit is not necessaryfor Y connected windingssince i 0=0.

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    Equivalent Circuits (3)

    Field windingdt di

    Ldt

    di Li Rv d sf

    f f f f f 2

    3

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    Combined Equivalent Circuit on d Axis (1)

    dt

    iid

    Ldt

    di

    Li R

    dt

    di L

    dt di

    Li Rv

    f d

    md

    d

    lsr qd s

    f sf

    d d r qd sd

    )( '

    d axis equivalent circuit and field winding equivalent circuit can be combined:

    md lsd L L L

    mf lf f L L L

    mf

    sf

    sf

    md

    f

    a

    L

    L

    L

    L

    N

    N N

    3

    2

    N

    ii

    L

    Li f f

    md

    sf f

    3

    2'

    f ad sf

    f d mf

    ad md

    N N C L

    N C L

    N C L

    23

    2

    2)

    21(

    82

    0 g

    avd P g

    Dl C

    From

    (Details @ InductanceSM.ppt)

    Let

    a N f N and are effective number of turns of armature andfield windings.

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    Combined Equivalent Circuit on d Axis (2)

    dt di

    Ldt

    di Li Rv d sf

    f f f f f 2

    3 '23

    f f Nii

    dt di

    NLdt

    di NLdt

    di NLi NR Nv

    d sf

    f mf

    f lf f f f 2

    3

    mf

    sf

    sf

    md

    L

    L

    L L

    N 32

    dt di

    Ldt

    di L

    dt

    di L N i R N Nv d md

    f sf

    f lf f f f

    '2'2

    23

    23

    dt

    iid L

    dt

    di Li Rv f d md

    f lf f f f

    )( ''''''

    lf lf

    f f

    f f

    L N L

    R N R

    Nvv

    2'

    2'

    '

    2323

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    Combined Equivalent Circuit on d Axis (3)

    dt

    iid L

    dt di

    Li Rv f d md d

    lsr qd sd

    )( '

    dt iid

    Ldt

    di Li Rv f d md

    f lf f f f

    )( ''''''

    From

    f f Nvv'

    '

    23

    f f Nii

    we get

    md md d ls

    f sf d d d

    i Li L

    i Li L

    ' f d md iii

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    dq Theory for Permanent MagnetSynchronous Machine (PMSM)

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    Parks Transformation

    Stator quantities ( S abc) of current, voltage, or flux can beconverted to quantities ( S dq0) referenced to the rotor.

    This conversion comes through the K matrix.

    01

    0

    dqabc

    abcdq

    SK S

    KSS

    13/2sin3/2cos

    13/2sin3/2cos1sincos

    2/12/12/1

    3/2sin3/2sinsin3/2cos3/2coscos

    32

    1

    meme

    meme

    meme

    mememe

    mememe

    K

    K

    13/2cos3/2sin

    13/2cos3/2sin1cossin

    2/12/12/13/2cos3/2coscos3/2sin3/2sinsin

    32

    1

    r r

    r r

    r r

    r r r

    r r r

    K

    K

    where

    or

    (MITs notation)

    (Purdues notation)

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    Voltage Equations (1)

    abcabcS abc dt d iR v

    010101 dqdqS dq dt d

    K iK R vK

    01

    01

    01

    dqdqS dq dt d

    K K iK KR vK K

    01

    01

    01

    0 dqdqdqS dq dt d

    dt d

    K K KK iK KR v

    01

    000 dqdqdqS dq dt d

    dt d

    K K iR v

    100

    010001

    sS RR

    For stator winding

    Under motor reference convention for currents(i.e. the positive reference direction for currents is into the machine):

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    Voltage Equations (2)

    We derive the derivative of K-1:

    Then, we get

    000

    00

    001

    r

    r

    dt d

    K K

    000

    dt

    d i R

    dt d

    i Rdt

    d i R

    v

    vv

    s

    r d qq s

    r qd d s

    q

    d

    03/2sin3/2cos03/2sin3/2cos0sincos

    03/2cos3/2sin

    03/2cos3/2sin0cossin

    1

    r r

    r r

    r r

    r

    meme

    meme

    meme

    medt d

    K

    dt d me

    me

    And for voltage, we get

    2 P

    dt d

    mmer

    r

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    Dynamical Equations for Flux Linkage

    000 i Rv

    i Rv

    i Rv

    dt

    d

    s

    r d q sq

    r qd sd

    q

    d

    The derivations so far are valid for both linear and nonlinear models.

    0

    0

    q

    d

    dq

    00 i Rv

    i Rvi Rv

    s

    r d q sq

    r qd sd

    V

    Let

    we haveV

    dt

    d dq 0

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    Flux Linkage vs. Current (1)

    The next step is to relate current to flux linkage throughinductances. For salient pole rotor, the inductances canbe approximately expressed as

    cccbca

    bcbbba

    acabaa

    abc

    L L L

    L L L

    L L LL

    32

    2cos

    322cos

    2cos

    me B Alscc

    me B Alsbb

    me B Alsaa

    L L L L

    L L L L

    L L L L

    Note: Higher order harmonics are neglected.

    or:

    32

    2cos

    322cos

    2cos

    r B Alscc

    r B Alsbb

    r B Alsaa

    L L L L

    L L L L

    L L L L

    2

    mer

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    Flux Linkage vs. Current (2)

    32

    2cos21

    2cos21

    32

    2cos21

    me B Acaac

    me B Acbbc

    me B Abaab

    L L L L

    L L L L

    L L L L

    Note: Higher order harmonics are neglected.

    or:

    32

    2cos21

    2cos21

    32

    2cos21

    r B Acaac

    r B Acbbc

    r B Abaab

    L L L L

    L L L L

    L L L L

    2

    mer

    Ref: 1. A. E. Fitzgerald, C. Kingsley, Jr., and S. D. Umans, Electric Machinery,6 th Edition, pages 660-661.

    2. P. C. Krause, O. Wasynczuk, and S. D. Sudhoff, Analysis of Electric Machinery and Drive Systems, 2 nd Edition, page 52,

    also pages 264-265.

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    Flux Linkage vs. Current (4)

    This matrix can be transformed into dq0 form and used tofind flux linkage.

    PMabcabcabcabc iL

    PMabcdqabcf dq iK L K 0101

    PMabcdqabcdq K iK KL K K 0101

    0000 PMdqdqdqdq iL

    PMabcdqabcdq K iK KL 01

    0

    where

    )3/2cos(

    )3/2cos(

    )cos(

    me

    me

    me

    PM PMabc

    or:

    2

    mer )3/2sin(

    )3/2sin(

    )sin(

    r

    r

    r

    PM PMabc

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    Inductance Matrix in dq0 Frame

    Therefore, we get the following inductance matrix in dq0frame:

    0

    10

    0000

    00

    L L

    L

    q

    d

    abcdq K KLL

    where

    )(23

    )(23

    B Amq

    B Amd

    L L L

    L L L

    ls

    mqlsq

    md lsd

    L L

    L L L

    L L L

    0

    and

    From00 i L

    i L

    i L

    ls

    qqq

    PM d d d

    0000 PMdqdqdqdq iL

    000

    PM

    PMabc PMdq

    K

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    Dynamical Equation in terms of Current

    V

    dt

    d dq 0For linear model from

    VLi

    1

    0

    0

    dq

    dq

    dt

    d dynamical equationin terms of current

    00 i Rv

    i Rv

    i Rv

    s

    r d q sq

    r qd sd

    V

    and

    whereqqq

    PM d d d

    i L

    i L

    0000 PMdqdqdqdq iL

    0

    0

    00

    00

    00

    L

    L

    L

    q

    d

    dqL

    0000 /)(/)(

    /)(

    Li Rv Li Li Rv

    Li Li Rv

    ii

    i

    dt d

    s

    q PM r d d r q sq

    d qqr d sd

    q

    d

    For Y connected winding, since , only need to considerthe first two equations for i d and i q .

    0)(3

    10 cba iiii

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    Power

    Electrical instantaneous Input Power on Stator can also beexpressed through dq0 theory.

    011

    0 )( dqT T

    dqabcT abcccbbaain iviviv p iK K viv

    00223 iviviv p qqd d in

    200010

    001

    23

    )(11 K K T

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    Torque

    00223

    iviviv p qqd d in

    000

    dt d i R

    dt d

    i R

    dt d

    i R

    v

    v

    v

    s

    r d qq s

    r qd d s

    q

    d

    From

    we have

    )(223

    22

    3

    22

    3 00

    2

    0

    22

    d qqd m

    q

    q

    d

    d qd sin ii

    P

    dt

    d

    idt

    d

    idt

    d

    iiii R p

    Copper LossMechanical PowerMagnetic Power in

    WindingsTherefore, electromagnetic torque on rotor

    )(22

    3d qqd

    m

    meche ii

    P pT

    mech p

    qqq

    PM d d d

    i L

    i L

    qd qd q PM e ii L Li P T )(

    22

    3

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    Dynamical Equations of Motion

    mm

    damp Lem

    dt d

    T T T dt

    d J

    where

    qT qd qd q PM e i K ii L Li P T )(22

    3

    For round rotor machine, qd L L q PM e i P T 43

    mmdamp DT D m is combined damping coefficient of rotorand load.

    d qd PM q

    eT i L L

    P iT

    K )(4

    3 torque constant

    PM T P K 43

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    dq Theory for Synchronous Machinewith Damper Winding

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    Relevance to Synchronous Machine

    dq means direct and quadrature. Direct axis is aligned withthe rotors pole. Quadrature axis refers to the axis whoseelectrical angle is orthogonal to the electric angle of direct

    axis.

    a axis

    d axisq axis

    b axis

    c axis

    m a

    d

    mq

    22

    2

    memqr

    mme

    P

    P min g

    max,or r

    min,or r max g

    isr

    d

    a axis

    m a

    q axis

    mq

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    Parks Transformation

    Stator quantities ( S abc) of current, voltage, or flux can beconverted to quantities ( S dq0) referenced to the rotor.

    This conversion comes through the K matrix.

    01

    0

    dqabc

    abcdq

    SK S

    KSS

    13/2sin3/2cos

    13/2sin3/2cos1sincos

    2/12/12/1

    3/2sin3/2sinsin3/2cos3/2coscos

    32

    1

    meme

    meme

    meme

    mememe

    mememe

    K

    K

    13/2cos3/2sin

    13/2cos3/2sin1cossin

    2/12/12/13/2cos3/2coscos3/2sin3/2sinsin

    32

    1

    r r

    r r

    r r

    r r r

    r r r

    K

    K

    where

    or

    (MITs notation)

    (Purdues notation)

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    Voltage Equations (1)

    abcabcS abc dt d iR v

    010101 dqdqS dq dt d

    K iK R vK

    01

    01

    01

    dqdqS dq dt d

    K K iK KR vK K

    01

    01

    01

    0 dqdqdqS dq dt d

    dt d

    K K KK iK KR v

    01

    000 dqdqdqS dq dt d

    dt d

    K K iR v

    100

    010

    001

    sS RR

    For stator windings

    Under motor reference convention for currents(i.e. the positive reference direction for currents is into the machine):

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    Voltage Equations (2)

    We derive the derivative of K-1:

    Then, we get

    00000

    001

    r

    r

    dt d

    K K

    000

    dt d

    i R

    dt d

    i Rdt

    d i R

    v

    vv

    s

    r d qq s

    r qd d s

    q

    d

    03/2sin3/2cos

    03/2sin3/2cos0sincos

    03/2cos3/2sin

    03/2cos3/2sin0cossin

    1

    r r

    r r

    r r

    r

    meme

    meme

    meme

    medt d

    K

    dt d me

    me

    And for stator voltage, weget

    2 P

    dt d

    mmer

    r

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    Voltage Equations (3)

    For rotor windings:

    We assume the rotor has field winding (magnetic field along d axis),one damper with magnetic field along d axis and one damper

    with magnetic field along q axis.

    qd qd qd k fk k fk r k fk dt d

    iR v

    q

    d

    k

    k

    f

    r

    R

    R

    R

    00

    00

    00R

    0

    0 f

    k fk

    v

    qd v

    q

    d qd

    k

    k

    f

    k fk

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    Voltage Equations (4)

    qqq

    d d d

    k k k

    k k k

    f f f

    s

    qr d q s

    d r qd s

    f

    q

    d

    dt

    d i R

    dt d

    i Rdt

    d i R

    dt d

    i Rdt

    d i R

    dt d

    i R

    v

    v

    v

    v

    000

    00

    In summary:

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    Dynamical Equations for Flux Linkage

    qq

    d d

    q

    d

    k k

    k k

    f f f

    s

    r d q sq

    r qd sd

    k

    k

    f

    q

    d

    i R

    i Ri Rv

    i Rv

    i Rv

    i Rv

    dt

    d 000

    The derivations so far are valid for both linear and nonlinear models.

    Let

    we have V

    dt

    d dqf

    q

    d

    k

    k

    f

    q

    d

    dqf

    0

    qq

    d d

    k k

    k k

    f f f

    s

    r d q sq

    r qd sd

    i R

    i R

    i Rv

    i Rv

    i Rv

    i Rv

    00

    V

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    Flux Linkage vs. Current (1)

    The next step is to relate current to flux linkage throughinductances. For salient pole rotor, the inductances canbe approximately expressed as

    32

    2cos

    322cos

    2cos

    me B Alscc

    me B Alsbb

    me B Alsaa

    L L L L

    L L L L

    L L L L

    or:

    32

    2cos

    322cos

    2cos

    r B Alscc

    r B Alsbb

    r B Alsaa

    L L L L

    L L L L

    L L L L

    2

    mer

    rr T sr

    sr ssabcf LL

    LLL

    cccbca

    bcbbba

    acabaa

    ss

    L L L

    L L L

    L L LL

    qd

    qd

    qd

    ck ck cf

    bk bk bf

    ak ak af

    sr

    L L L

    L L L

    L L LL

    qd qq

    qd d d

    qd

    k k k f k

    k k k f k

    fk fk f

    rr

    L L L

    L L L

    L L LL

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    Flux Linkage vs. Current (2)

    32

    2cos21

    2cos21

    32

    2cos21

    me B Acaac

    me B Acbbc

    me B Abaab

    L L L L

    L L L L

    L L L L

    32

    cos

    3

    2cos

    cos

    me sf fccf

    me sf fbbf

    me sf faaf

    L L L

    L L L

    L L Lor:

    32

    2cos21

    2cos21

    32

    2cos21

    r B Acaac

    r B Acbbc

    r B Abaab

    L L L L

    L L L L

    L L L L

    32

    sin3

    2sin

    sin

    r sf fccf

    r sf fbbf

    r sf faaf

    L L L

    L L L

    L L L

    2

    mer

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    Flux Linkage vs. Current (3)

    32

    cos

    32

    cos

    cos

    me sk ck ck

    me sk bk bk

    me sk ak ak

    d d d

    d d d

    d d d

    L L L

    L L L

    L L L

    or:

    32

    sin

    32

    sin

    sin

    r sk ck ck

    r sk bk bk

    r sk ak ak

    d d d

    d d d

    d d d

    L L L

    L L L

    L L L

    2 mer

    32

    sin

    32

    sin

    sin

    me sk ck ck

    me sk bk bk

    me sk ak ak

    qqq

    qqq

    qqq

    L L L

    L L L

    L L L

    32

    cos

    32

    cos

    cos

    r sk ck ck

    r sk bk bk

    r sk ak ak

    qqq

    qqq

    qqq

    L L L

    L L L

    L L L

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    Flux Linkage vs. Current (4)

    Note: Higher order harmonics are neglected in the above expressions.

    Ref: 1. A. E. Fitzgerald, C. Kingsley, Jr., and S. D. Umans, Electric Machinery,6 th Edition, pages 660-661.

    2. P. C. Krause, O. Wasynczuk, and S. D. Sudhoff, Analysis of Electric Machinery and Drive Systems, 2 nd Edition, pages 52and 195.

    qqq

    d d d

    mk lk k

    mk lk k

    mf lf f

    L L L

    L L L

    L L L

    0

    0

    d qqd

    qq

    d d

    k k k k

    f k fk

    f k fk

    L L

    L L

    L L

    l i k C ( )

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    Flux Linkage vs. Current (5)

    This matrix can be transformed into dq form and used tofind flux linkage.

    abcf abcf abcf iL

    qd k fk sr dq ssdqiLiK L K

    01

    01

    dqf dqf dqf iL

    qd k fk sr dq ssdqiKLiK KL

    0

    1

    0

    r T sr

    sr ssabcf

    LL

    LLL

    qd k fk

    abc

    abcf

    qd k fk

    abc

    abcf i

    ii

    qd k fk sr abc ssabciLiL

    qd qd k fk rr abcT sr k fk

    iLiL qd qd k fk rr dq

    T sr k fk

    iLiK L 0

    1

    rr

    T

    sr

    sr ssdqf LK L

    KLK KLL

    1

    1

    qd k fk

    dqdqf

    0

    qd k fk

    dqdqf i

    ii

    0

    From with

    where

    I d M i i d F

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    Inductance Matrix in dq Frame

    qq

    d d d

    d

    q

    d

    k sk

    k f k sk

    fk f sf

    sk q

    sk sf d

    dqf

    L L

    L L L

    L L L L

    L L

    L L L

    000230

    00023

    00023 00000

    0000

    000

    0

    L

    where

    )(23

    )(23

    B Amq

    B Amd

    L L L

    L L L

    mqlsq

    md lsd

    L L L

    L L L

    and

    dqf dqf dqf iL From q sk k k k

    f fk d sk k k k

    k fk d sf f f f

    k sk qqq

    k sk f sf d d d

    i Li L

    i Li Li L

    i Li Li L

    i L

    i Li L

    i Li Li L

    qqqq

    d d d d d

    d d

    qq

    d d

    2323

    23

    000

    Through derivations, we have

    rr T sr

    sr ss

    dqf LK L

    KLK KLL

    1

    1

    ls L L0

    D i l E ti i t f C t

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    Dynamical Equation in terms of Current

    V

    dt

    d dqf For linear model

    from

    VLi 1dqf

    dqf

    dt d dynamical equation

    in terms of current

    dqf dqf dqf iL

    qq

    d d

    k k

    k k

    f f f

    s

    r d q sq

    r qd sd

    i R

    i Ri Rv

    i Rv

    i Rvi Rv

    00

    V

    and

    where

    qq

    d d

    k sk qqq

    k sk f sf d d d

    i Li L

    i Li Li L

    P

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    Power

    Electrical instantaneous Input Power on Stator can also beexpressed through dq0 theory.

    0

    11

    0 )( dqT T

    dqabc

    T

    abcccbbaain iviviv piK K viv

    00223 iviviv p qqd d in

    200

    010

    001

    2

    3)( 11 K K T

    Torque

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    Torque

    00223

    iviviv p qqd d in

    000

    dt d i R

    dt d

    i R

    dt d

    i R

    v

    v

    v

    s

    r d qq s

    r qd d s

    q

    d

    From

    we have

    )(22

    32

    2

    32

    2

    3 00

    20

    22d qqd m

    qq

    d d qd sin ii

    P

    dt

    d i

    dt

    d i

    dt

    d iiii R p

    Copper LossMechanical PowerMagnetic Power inWindings

    Therefore, electromagnetic torque on rotor

    )(22

    3d qqd

    m

    mech

    e ii

    P p

    T

    mech p

    Equivalent Circuit on d Axis (1)

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    Equivalent Circuit on d Axis (1)

    d axis of stator, field winding and d axis damper of rotor can form an equivalentcircuit.

    Let md lsd L L L

    mf lf f L L L

    d d d mk lk k L L L

    d d

    d d

    d d

    k f d fk

    k ad sk

    k d mk

    f ad sf

    f d mf

    ad md

    N N C L

    N N C L

    N C L

    N N C L

    N C L

    N C L

    2

    3

    2

    2

    2

    )21(8

    20 g

    avd P g

    Dl C

    From

    (Details @ Inductance for SM.ppt)

    , a N f N and are effective number of turns of armature, field and d axis

    damper windings, respectively.

    d k N

    Equivalent Circuit on d Axis (2)

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    Equivalent Circuit on d Axis (2)

    dt

    iiid L

    dt di

    Li R

    dt

    di L

    dt

    di L

    dt

    di Li Rv

    d

    d

    d

    k f d md

    d lsr qd s

    k sk

    f sf

    d d r qd sd

    )( ''

    f a

    f f

    md

    sf f i

    N

    N i

    L

    Li

    32'Define

    d

    d

    d

    d

    d k a

    k k

    md

    sk k i

    N

    N i

    L

    Li

    32'and

    dt

    di L

    dt di

    Ldt

    di Li Rv d

    d

    k fk

    d sf

    f f f f f 2

    3

    dt di NL

    dt di NL

    dt di NL

    dt di NLi NR Nv d d k fk d sf f mf f lf f f f 2

    3

    dt

    di L

    N

    N

    N

    N

    dt

    di L

    dt

    di L

    dt

    di L N i R N Nv d

    d

    d

    k fk

    k

    a

    f

    ad md

    f sf

    f lf f f f

    ''2'2

    2

    3

    2

    3

    2

    3

    Define

    f f Nvv'

    a

    f

    N N

    N and

    Equivalent Circuit on d Axis (3)

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    Equivalent Circuit on d Axis (3)

    dt

    iiid L

    dt

    di Li Rv d k f d md

    f lf f f f

    )( '''''''

    lf f

    alf

    f f

    a

    f

    L N

    N L

    R N

    N

    R2

    '

    2

    '

    23

    2

    3

    where

    2

    32

    a

    k f

    md

    fk

    N N N

    L L d d

    dt

    di

    Ldt di

    Ldt

    di

    Ldt

    di

    Li R

    dt

    di L

    dt di

    Ldt

    di Li R

    f

    fk

    d

    sk

    k

    mk

    k

    lk k k

    f fk

    d sk

    k k k k

    d d

    d

    d

    d

    d d d

    d d

    d

    d d d

    23

    23

    0From

    above

    3

    2

    d d k

    a

    sk

    md

    N

    N

    L

    L

    next page

    Equivalent Circuit on d Axis (4)

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    Equivalent Circuit on d Axis (4)

    dt

    di L

    N N

    N dt di

    Ldt

    di L

    N

    N dt

    di L

    N

    N i R

    N

    N f fk

    k f

    ad md

    k mk

    k

    ak lk

    k

    ak k

    k

    ad

    d

    d

    d

    d

    d

    d

    d

    d d

    d

    '2'2

    '2

    '

    2

    23

    23

    23

    23

    0

    dt

    iiid Ldt

    di Li R

    d d

    d d d

    k f d md

    k lk k k

    )(0

    ''''''

    where

    d

    d

    d

    d

    d

    d

    lk k

    alk

    k k

    ak

    L N

    N L

    R N

    N R

    2

    '

    2

    '

    23

    2

    3

    d d

    d d

    k f

    a

    fk

    md

    k

    a

    mk

    md

    N N

    N L L

    N

    N L L

    23

    23

    2

    2

    Equivalent Circuit on d Axis (5)

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    Equivalent Circuit on d Axis (5)

    From

    we get

    md md d ls

    k sk f sf d d d

    i Li L

    i Li Li Ld d

    ''d k f d md iiii

    dt iiid L

    dt di Li Rv d k f d md

    d lsr qd sd

    )(''

    dt

    iiid L

    dt

    di Li Rv d k f d md

    f lf f f f

    )( '''''''

    dt iiid L

    dt di Li R d d

    d d d

    k f d md

    k lk k k )(0

    '''

    '''

    'd k

    i

    Equivalent Circuit on q Axis (1)

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    Equivalent Circuit on q Axis (1)

    q axis equivalent circuit and q axis damper equivalent circuitcan be combined:

    Letmqlsq L L L

    qqq mk lk k L L L

    qq

    qq

    k aq sk

    k qmk

    aqmq

    N N C L

    N C L

    N C L

    23

    2

    2)

    21(8 2

    0

    P g Dl C av

    qFrom

    (Details @ Inductance for SM.ppt)

    s N and are effective number of turns of

    stator and q axis damperwindings, respectively.

    d k N

    Equivalent Circuit on q Axis (2)

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    Equivalent Circuit on q Axis (2)

    dt

    iid L

    dt

    di Li R

    dt

    di L

    dt

    di L

    dt

    di Li R

    dt

    di L

    dt

    di Li Rv

    q

    q

    q

    q

    q

    k q

    mqq

    lqr d q s

    k

    sk q

    mqq

    lqr d q s

    k

    sk q

    qr d q sq

    )(

    '

    q

    q

    q

    q

    d k

    a

    k

    k

    md

    sk

    k i N

    N i

    L

    Li

    3

    2'where

    dt

    di

    Ldt

    di

    Ldt

    di

    Li R

    dt

    di L

    dt

    di Li R

    q

    sk

    k

    mk

    k

    lk k k

    q sk

    k

    k k k

    q

    q

    q

    q

    qqq

    q

    q

    qqq

    23

    23

    0From

    above

    3

    2

    qq k

    a

    sk

    mq

    N

    N

    L

    L

    next page

    Equivalent Circuit on q Axis (3)

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    q q ( )

    dt

    di L

    dt

    di L

    N

    N dt

    di L

    N

    N i R

    N

    N qmq

    k

    mk k

    ak

    lk k

    ak k

    k

    a q

    q

    q

    q

    q

    q

    qq

    q

    '2'2'

    2

    23

    23

    23

    0

    dt

    iid Ldt

    di Li R

    qq

    qqq

    k q

    mq

    k

    lk k k

    )(0

    '''''

    where

    q

    q

    q

    q

    q

    q

    lk k

    alk

    k k

    ak

    L N

    N L

    R N

    N R

    2

    '

    2

    '

    23

    2

    3

    qq

    qq

    k f

    a

    fk

    mq

    k

    a

    mk

    mq

    N N

    N L

    L

    N

    N

    L

    L

    23

    2

    3

    2

    2

    Equivalent Circuit on q Axis (4)

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    q q ( )

    From

    we get

    mqmqqls

    k sk qqq

    i Li L

    i Li Lqq

    'qk qmq

    iii

    dt iid L

    dt di Li Rv q

    k qmq

    qlqr d q sq

    )('

    dt

    iid L

    dt

    di Li R qq

    qqq

    k q

    mq

    k

    lk k k

    )(0

    '''''

    'qk

    i

    Equivalent Circuit on 0 Axis

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    q

    0 axisdt di

    Li Rv s0

    000

    This circuit is not necessaryfor Y connected windingssince i 0=0.

    Dynamical Equations fromEquivalent Circuits (1)

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    Equivalent Circuits (1)

    dt di

    Li Rv

    dt di L

    dt di Li Rv

    dt

    di L

    dt

    di Li R

    dt di L

    dt di Li R

    dt

    di L

    dt

    di Li Rv

    dt di L

    dt di Li Rv

    ls s

    md md

    f lf f f f

    mqmq

    k

    lk k k

    md md

    k lk k k

    mqmq

    qlsqd r q sqq

    md md

    d lsd qr d sd d

    q

    qqq

    d

    d d d

    00000

    '''''

    ''''

    ''''

    0

    0

    where

    '

    ''

    q

    d

    k qmq

    k f d md

    iii

    iiii

    Dynamical Equations fromEquivalent Circuits (2)

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    Equivalent Circuits (2)The equations can be written in matrix form as:

    VI

    Ldt d

    where

    mqlk mq

    md lk md md

    md md lf md

    ls

    mqmqlsq

    md md md lsd

    L L L

    L L L L

    L L L L

    L

    L L L

    L L L L

    q

    d '

    '

    '0

    0000000

    000

    000000000

    000

    L

    '

    '

    '0

    q

    d

    k

    k

    f

    q

    d

    i

    i

    ii

    i

    i

    I

    ''

    ''

    '''000

    qq

    d d

    k k

    k k

    f f f

    s

    d r q sqq

    qr d sd d

    i R

    i R

    i Rvi Rv

    i Rv

    i Rv

    V

    VLI 1

    dt d or