基于Simulink的发电厂接入大电网的仿真模型,求助各位帮忙
本帖最后由 shanby 于 2014-12-21 21:17 编辑接线情况: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母线接入3相短路模块,求解短路电流。模型见附件。参数设置可能不合理。仿真时Simulink提示错误信息为:
The following two blocks cannot be connected in series:
Block 1: 'A: Simplified Synchronous Machine SI Units1'
Block 2: 'transfo_1_winding_2: Split winding type transformer1'
The first block, modeled as a current source, cannot be connected in series with the inductive element of the second block.
Add a high-value resistance in parallel with one of the two block.
You can also specify high-value resistive snubbers if the blocks have a snubber device.
意思是名字叫Simplified Synchronous Machine SI Units1的发电机是一个电流源,不能与感性元件(变压器,名字为transfo_1_winding_2: Split winding type transformer1)连接。需要与发电机并联一个高值电阻。请问大家我错在哪里?参数改如何设置。有好心人麻烦就自己理解修改这个模型的参数上传,万分感谢。
说得已经很清楚了,让你在发电机机端并联一个电阻。 我并了一个大电阻,没有数据啊。你们呢? 并联一个三相并联RLC负荷应该就可以了 本帖最后由 shanby 于 2014-12-31 11:45 编辑
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 ...
shanby 发表于 2014-12-21 21:06 https://tech.cepsc.com/images/common/back.gif
查看如下帮助文档:Assumptions
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
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.
得出:
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;
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)
试错结论:
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)
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。
3.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)。
疑问:
1.如何解释模型搭建、报错和试错结论?
2.Simulink仿真的逻辑?
为什么接两个transformer呢 而且还要从一个驱动器出来吗 把变压器的电感设置为零,就可以解决了
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