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发表于 2014-12-31 11:34:51
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本帖最后由 shanby 于 2014-12-31 11:45 编辑 * H/ {3 F- l* l8 N7 O' T, R
接线情况：模拟2台150MW，35kV的发电机分别接入2台分裂升压变压器，再由220kV接入大电网。在35kV母线接 ...
; F7 S& N/ a; r7 T' c$ pshanby 发表于 2014-12-21 21:06
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( N. f5 S/ D6 R5 z* I$ ?( L 查看如下帮助文档：Assumptions1 `4 H4 h+ D: W
The electrical system of the Simplified Synchronous Machineblock consists solely of a voltage source behind a synchronous reactanceand resistance. All the other self- and magnetizing inductances ofthe armature, field, and damping windings are neglected. The effectof damper windings is approximated by the damping factor Kd. The threevoltage sources and RL impedance branches are Y-connected (three wiresor four wires). The load might or might not be balanced.Limitations. G& t5 H& u: {8 ]) w
When you use Simplified Synchronous Machine blocks in discretesystems, you might have to use a small parasitic resistive load, connectedat the machine terminals, in order to avoid numerical oscillations.Large sample times require larger loads. The minimum resistive loadis proportional to the sample time. As a rule of thumb, remember thatwith a 25 μs time step on a 60 Hz system, the minimum load isapproximately 2.5% of the machine nominal power. For example, a 200MVA simplified synchronous machine in a power system discretized witha 50 μs sample time requires approximately 5% of resistive loador 10 MW. If the sample time is reduced to 20 μs, a resistive loadof 4 MW should be sufficient.
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1 }5 q# F( `5 }+ }得出：1 W# x9 F# d' C l$ m {. B' i
1.简单同步发电机模型采用带电阻和电抗、独立电压源，三相Y连接的电气模型；, \/ C6 E/ f3 c0 M$ {
2.使用边界限制：如果是采用离散系统仿真，则需要在发电机端子连接寄生小电阻，其阻值或功率与离散系统的采样时间成比例（举例有计算实例）
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$ z& R) C5 y+ C, ]试错结论：
9 I6 G9 `! B) ?# s: T7 [1.错误提示说简单同步发电机是电流源，需要并联高值电阻。这与帮助文档电压源的说法不一致（尽管电压源和电流源和也互相变换）
* Y g5 \5 N& d% |2.将powergui模块参数设置为continous，仿真报错与设置为discrete的报错信息一样。
. Z6 T a! Y5 d% F3.将powergui模块参数设置为discrete， 按错误提示边栏电阻，则仿真不报错（虽然结果不是预期）。
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ShortCurrentFor300MW2.rar
(9.71 KB, 下载次数: 1)
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电压波形
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5 k: n. v0 V% ~疑问：; o2 r8 f/ [% W) t9 b) w6 S- C$ b5 f
1.如何解释模型搭建、报错和试错结论？
- L* i* X( p" V0 h2 \6 S7 ?/ D2.Simulink仿真的逻辑？
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发表于 2014-12-21 21:06:44
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