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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.$ e ?9 C2 N+ y; y+ C% _1 o% {
There is a ramping time you can choose. The ramping pattern can be linear, exponential or other...3 T" ^ B6 U0 i; L' c
for instance, linear...
7 ~; U! f: h2 y( rVa=Vm*t*sinwt- G$ D" k4 T" a& a( N
Vb=Vm*t*sin(wt-120)
: M% V& h* {0 n }Va=Vm*t*sin(wt+120)# m) N0 h* H! G0 m6 }
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when t=0, va=0, vb=0 and Vc=0 np problem.
3 i' ~; s, V0 _( \, c+ Lt can be normalized so that the magnitude can be ramp to the Vm in certain time, then stays there./ Q$ }4 ?4 y; |, L( r9 [ U
. a& x) g, n0 ]6 GThere is no problem to implement this.' q. a, }, A. A3 \7 G2 o
# H7 ]5 r0 b/ V! h0 E, m: z# r; fAnyway, 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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/ ]! C% Q) H# SThose programming tip/detail is no that important, but sometime fun...
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Help the above helps. |
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