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发表于 2009-11-18 11:36:55
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Name : SatTrafo - General saturable transformer. 3 phase. 2 or 3 windings.5 h0 r( f7 S+ T j" o! T
Wye, Delta with all phase shifts. Auto, and Zigzag with most common configurations.
$ u; C$ G7 x/ a. } SCard : BRANCH) N2 i/ S: F X3 Q
Data : Io= Current [A] through magnetizing branch (MB) at steady state.
% K4 u# b2 L- o \ Fo= Flux [Wb-turn] in MB at steady state.
' H2 ?* v& x7 d6 |- A V0 {& s" ]% N The pair Io, Fo defines the inductance in MB at steady state.0 M* L6 P$ G7 l3 E
Rm= Resistance in magnetizing branch in [ohm]. 5-leg core or 3-leg shell.# ]- O3 D; p0 `$ E" m, g' a3 f
The magnetizing branch is always connected to the PRIMARY winding and Rm is referred to this voltage.
B: P, v9 s" @ y. t R0= Reluctance of zero-sequence air-return path for flux. 3-leg core-type4 f- O9 |6 Q7 p" N
Vrp= Rated voltage in [V] primary winding (only the voltage ratios matter).
7 S0 w* G1 }. @; k7 G Rp= Resistance in primary winding in [ohm].! L4 x+ g7 Y. f; b4 k4 P$ F8 W. _, b
Lp= Inductance in primary winding in [mH] if Xopt.=0" g, R5 m6 Y- y: F3 ]9 c
Inductance in primary winding in [ohm] if Xopt.=power freq.; A. J8 G/ t F
Vrs= Rated voltage in [V] secodary winding.
. T, [+ c# M8 `0 B Rs= Resistance in secondary winding in [ohm].
7 W, W( }7 X4 v4 Q1 b9 E Ls= Inductance in secondary winding in [mH] if Xopt.=0
+ \" [! B7 b+ p0 ~" E Inductance in secondary winding in [ohm] if Xopt.=power freq.
* V, b5 f4 I ~. P" l Vrt= Rated voltage in [V] tertiary winding.2 v& f2 k) B2 |7 |! r, G
Rt= Resistance in tertiary winding in [ohm].0 g( H" j: l$ Q4 ^7 A, J
Lt= Inductance in tertiary winding in [mH] if Xopt.=0
1 ?; H0 k4 z' C( O3 } Inductance in tertiary winding in [ohm] if Xopt.=power freq.
% ]7 y0 F5 G$ x! D& I- k; M RMS= unchecked: Current/Flux characteristic must be entered.
( X( o3 B+ q3 E- o checked: Irms/Urms characteristic must be entered.) U/ F! M2 E5 s: e; Z+ q
ATPDRAW performs a SATURATION calculation.
; b: {6 P% Z9 o' j 3-leg core = checked: 3-leg core type transformer assumed. TRANSFORMER THREE PHASE7 Z- I& ^$ [8 n# o0 N
unchecked: 5-leg or 3-leg shell type assumed. TRANSFORMER.
. y0 m w; z$ P" I3 I( W 3-wind.= turn on tertiary winding.
8 P" \- b. f6 qOutput specified the magnetization branch output (power&energy not supported). 4 {! z9 k: f% _2 t. v, C& S/ k
Node : P= Primary side. 3-phase node.
: d' ^% l. c! s3 ?7 \( V7 M S= Secondary side. 3-phase node.& N8 F& C! ]5 v
PN= Neutral point primary side.6 F! r1 Q$ ` W# B4 N( d# B2 F D
SN= Neutral point secondary side.
$ n \8 k+ a, k9 ~- X T= Tertiary side. 3-phase node.
0 O# m" h1 _* H9 b) \ Q) r TN= Neutral point tertiary side.
1 d- w# y% J4 Z: r, e8 {: t Sat= Internal node, connection of the magnetization circuit with saturation.7 _5 X; N& q0 T! d
The coupling is specified for each winding, with four coupling options: Y, D, A, Z
6 E; d. ]: R- b% D/ y8 L All phase shifts are supported.
|1 o1 a+ P, f2 A" D+ K/ B3 d& sSpecial note on Auto-transformers:
& l7 ]( c/ H: {( [+ J$ Z& q7 \( h! w The primary and secondary windings must be of coupling A(uto).- ?: Y# G" N4 H# }. j* \
Special note on ZigZag-transformers: 8 P& @6 R- x# F M# @! R* T' r
For this type the user can specify a phase shift in the range <-60,0>&<0,60>.
+ C1 b; {' D( Y Note that the values -60, 0 and +60 degrees are illegal (as one of the winding parts degenerates).
3 U) t4 ^$ y, k The phase shift is given relative to a Y-coupled winding. 3 f! v" E- E4 w& r6 [1 ~4 s
If the primary winding is Zigzag-coupled, all other windings will be shifted with it.. \( L1 T1 P m' o& _
If the primary winding is D-coupled, 30 deg. must be added/subtracted to the phase shifts.
( i6 N' q# l3 y$ s For negative phase shifts the phase A winding starts on leg 1 (called z with voltage Uz) % ?) A. _: `+ e \- O
and continues in the opposite direction on leg 3 (called y with voltage Uy).
( r0 S- ?1 b# C. u( ~: r For negative phase shifts the phase A starts on leg 1 8 O1 j, |7 O: h% A! p
and continues in the opposite direction on leg 2. 6 e7 p5 x9 E" Z( W$ x# ]/ x, q+ A7 x7 T
The normal situation is to specify a phase shift of +/- 30 deg.
3 E! @" G+ J5 C/ h: Y in which case the two parts of the winding have the same voltage level and leakage impedance.
1 ?' R% Y5 U+ [( e1 } In general the ratio between the second part of the winding Uy and the first part Uz is
8 k7 f6 }! _" d6 t n=Uy/Uz=sin(a)/sin(60-a) where a is absolute value of the phase shift.
) [8 K6 [2 f7 s$ x* _8 m This gives:9 h5 B) K; Q3 y' C s) ~) M
Uz=U/(cos(a)+n*cos(60-a)) and Uy=Uz*n' T/ X1 H8 ]) l N6 n6 k& Z
Lz=L/(1+n*n) and Ly=Lz*n*n, Rz=R/(1+n) and Ry=Rz*n
9 Z* o7 W& B `8 m9 ~7 i7 s where Lz and Ly are the leakage inductance of each part of the winding (L is the total leakage inductance)
- \) s* ]$ f+ ]6 Y6 B1 k7 n and Rz and Ry are the winding resistance of each winding part (R is the total).* Z0 y. N- |7 p, W1 X
The parameters Uz, Uy, Zz, and Zy are automatically calculated by ATPDraw based on the 2 R" T# x1 L( E; n/ \5 g0 h& A
equivalent parameters U and Z and the phase shift, a.
6 I$ c& g4 z- H" Z+ W0 U: k# I+ Z& ^5 i
2 \4 I6 Y( e- m" _" TPoints: It's possible to enter 9 points on the current/flux characteristic.; p" D) A! T6 G
The required menu is performed immedeately after the input menu.
; ^# a) X" f- a5 v1 G2 h The points should be entered as increasingly larger values. 0 b+ S5 y8 c" l! @( ?5 S8 u
The point (0,0) is not permitted (added internally in ATP).0 |, \+ T( ]2 ?* q& \4 f$ O
RuleBook: IV.E.1-2 or 3. |
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