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发表于 2008-4-10 12:02:55
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Well, there are several source models in EMTDC/PSCAD, all ramping from 0.
% Y6 l: a: x, ^: a! gThere is a ramping time you can choose. The ramping pattern can be linear, exponential or other...! f' ?) }. E. k8 t/ E h
for instance, linear...! ^6 _" m: e5 F
Va=Vm*t*sinwt* e2 o! Y' L5 w% }& U
Vb=Vm*t*sin(wt-120)
; @9 v$ I; x( i+ {% ?- s$ EVa=Vm*t*sin(wt+120)/ ^2 u* `% {; r3 ^& y
. j) Y0 P: x( awhen t=0, va=0, vb=0 and Vc=0 np problem.! g0 w2 W% [5 e) T1 c
t can be normalized so that the magnitude can be ramp to the Vm in certain time, then stays there.
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6 x0 O8 F0 U' o7 p0 |$ xThere is no problem to implement this.1 D C9 ^5 Y/ x; b& i. H9 o+ A
; Q8 }: q# L; T/ Y" J0 ]Anyway, focusing on such small detail won't help you understand the simulation.
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If you are really interested in EMTDC, please read the manual carefully, and you should also read EMTP theory book and take power system analysis courses in university.
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Those programming tip/detail is no that important, but sometime fun...
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Help the above helps. |
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