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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
# n* u$ f3 ~7 l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 ...
( M; p7 W# n2 l6 P8 X' ^shanby 发表于 2014-12-21 21:06
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查看如下帮助文档:Assumptions$ q% t+ }" z% n
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
- V: \) F) b5 B0 lWhen 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.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;1 r, e' {' J f' h4 Y0 L
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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$ V. s& I. u. O/ r: i, [( ?试错结论:
2 `' H j. j$ c1 P1 Q- D- L# X1.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)
: g- R9 D# @ K0 [. Z W2.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。
2 ^6 x* P% l2 _# n3.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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疑问:
9 B9 [; o/ w6 E' {1.如何解释模型搭建、报错和试错结论?$ v7 S& r% p8 @
2.Simulink仿真的逻辑?
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