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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 0.8 s: x4 s% c) P
There is a ramping time you can choose. The ramping pattern can be linear, exponential or other...0 O& ^9 o$ \. X8 g, d
for instance, linear...
5 W5 g S* }: P+ CVa=Vm*t*sinwt
. q$ A; d' R' \$ dVb=Vm*t*sin(wt-120)1 U7 B$ ?6 N9 m! Y4 v5 P) U: B
Va=Vm*t*sin(wt+120)+ l' T# i3 W l3 @# \- Q+ G3 P/ S
6 i0 e+ B; d8 N- w2 Dwhen t=0, va=0, vb=0 and Vc=0 np problem.
- e& U% s9 e5 I" \: K9 Y6 z6 ?t can be normalized so that the magnitude can be ramp to the Vm in certain time, then stays there.
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8 Y; ~/ {0 K$ U' lThere is no problem to implement this.; a0 |1 Q$ f% f4 Z; x1 C7 J# d4 D* _
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Anyway, focusing on such small detail won't help you understand the simulation.
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2 J, Z6 w$ m3 j4 MIf 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.../ B0 ?$ f& S7 V! ?7 k- `
* ]3 V3 h* K' F. k, eHelp the above helps. |
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