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我正在使用 Wolfram 的 SystemModeler 来研究连接到永磁同步电机的逆变器的系统行为。不幸的是，尽管我只使用了 Modelica 标准库中的组件，但我得到了错误的模拟结果。

到目前为止，我在下面的模型中尝试了几种设置。

model InverterSMPM
  import Modelica.Constants.pi;
  parameter Integer m = 3 "Number of phases";
  parameter Modelica.SIunits.Frequency f = 1000 "Switching frequency";
  parameter Modelica.SIunits.Frequency f1 = 50 "Fundamental wave AC frequency";
  parameter Modelica.SIunits.Torque TLoad = 181.4 "Nominal load torque";
  parameter Modelica.SIunits.Inertia JLoad = 0.29 "Load's moment of inertia";
  Modelica.Electrical.Analog.Sources.ConstantVoltage constantVoltage_n(V = 50) annotation(Placement(transformation(extent = {{-10, -10}, {10, 10}}, rotation = 270, origin = {-105, 4}), visible = true));
  Modelica.Electrical.PowerConverters.DCAC.MultiPhase2Level inverter(useHeatPort = false, m = m) annotation(Placement(transformation(extent = {{-50, 20}, {-30, 40}}, origin = {-35, -6}, rotation = 0), visible = true));
  Modelica.Electrical.Analog.Basic.Ground ground annotation(Placement(transformation(extent = {{-10, -10}, {10, 10}}, rotation = 180, origin = {-125, 34}), visible = true));
  Modelica.Electrical.PowerConverters.DCDC.Control.SignalPWM signalPWM[m](each useConstantDutyCycle = false, each f = f) annotation(Placement(transformation(extent = {{-10, -10}, {10, 10}}, origin = {-75, -26}, rotation = 0), visible = true));
  Modelica.Electrical.Analog.Sources.ConstantVoltage constantVoltage_p(V = 50) annotation(Placement(transformation(extent = {{-10, -10}, {10, 10}}, rotation = 270, origin = {-105, 44}), visible = true));
  Modelica.Blocks.Sources.Sine sine[m](phase = -Modelica.Electrical.MultiPhase.Functions.symmetricOrientation(m), startTime = zeros(m), amplitude = fill(0.5, m), offset = fill(0.5, m), freqHz = fill(f1, m)) annotation(Placement(transformation(extent = {{-30, -64}, {-50, -44}}, origin = {-35, -6}, rotation = 0), visible = true));
  Modelica.Electrical.Machines.BasicMachines.SynchronousInductionMachines.SM_PermanentMagnet smpm(Jr = 0.29, p = 8, fsNominal = f1, VsOpenCircuit = 100, TsOperational = 293.15, TrOperational = 293.15, Rs = 4.7, TsRef = 293.15, alpha20s = Modelica.Electrical.Machines.Thermal.Constants.alpha20Aluminium, Lssigma = 0.001, Lmd = 0.0133, Lmq = 0.0133, useDamperCage = false) annotation(Placement(visible = true, transformation(origin = {5, -15}, extent = {{-10, -10}, {10, 10}}, rotation = 0)));
  Modelica.Electrical.Machines.Utilities.TerminalBox terminalBox1(terminalConnection = "Y") annotation(Placement(visible = true, transformation(origin = {5, 2.209}, extent = {{-10, -10}, {10, 10}}, rotation = 0)));
  Modelica.Mechanics.Rotational.Components.Inertia inertia1(J = JLoad) annotation(Placement(visible = true, transformation(origin = {35, -15}, extent = {{-10, -10}, {10, 10}}, rotation = 0)));
  Modelica.Mechanics.Rotational.Sources.TorqueStep torqueStep1(stepTorque = -TLoad, offsetTorque = 0, startTime = 2, useSupport = false) annotation(Placement(visible = true, transformation(origin = {76.657, -15}, extent = {{10, -10}, {-10, 10}}, rotation = 0)));
  Modelica.Mechanics.Rotational.Sensors.SpeedSensor speedSensor1 annotation(Placement(visible = true, transformation(origin = {35, 20}, extent = {{-10, -10}, {10, 10}}, rotation = 0)));
equation
  connect(constantVoltage_p.n, constantVoltage_n.p) annotation(Line(points = {{-70, 40}, {-70, 20}}, color = {10, 90, 224}, visible = true, origin = {-35, -6}));
  connect(constantVoltage_p.p, inverter.dc_p) annotation(Line(points = {{-70, 60}, {-50, 60}, {-50, 40}}, color = {10, 90, 224}, visible = true, origin = {-35, -6}));
  connect(constantVoltage_n.n, inverter.dc_n) annotation(Line(points = {{-70, -0}, {-50, 0}, {-50, 20}}, color = {10, 90, 224}, visible = true, origin = {-35, -6}));
  connect(ground.p, constantVoltage_p.n) annotation(Line(points = {{-90, 30}, {-70, 30}, {-70, 40}}, color = {10, 90, 224}, visible = true, origin = {-35, -6}));
  connect(sine.y, signalPWM.dutyCycle) annotation(Line(points = {{-51, -54}, {-60, -54}, {-60, -20}, {-52, -20}}, color = {1, 37, 163}, visible = true, origin = {-35, -6}));
  connect(signalPWM.fire, inverter.fire_p) annotation(Line(points = {{-46, -9}, {-46, 18}}, color = {190, 52, 178}, visible = true, origin = {-35, -6}));
  connect(signalPWM.notFire, inverter.fire_n) annotation(Line(points = {{-34, -9}, {-34, 18}}, color = {190, 52, 178}, visible = true, origin = {-35, -6}));
  connect(terminalBox1.plug_sn, smpm.plug_sn) annotation(Line(visible = true, origin = {-1, -4.396}, points = {{0, 0.604}, {0, -0.604}}, color = {10, 90, 224}));
  connect(terminalBox1.plug_sp, smpm.plug_sp) annotation(Line(visible = true, origin = {11, -4.396}, points = {{0, 0.604}, {0, -0.604}}, color = {10, 90, 224}));
  connect(smpm.flange, inertia1.flange_a) annotation(Line(visible = true, origin = {20, -15}, points = {{-5, 0}, {5, 0}}, color = {64, 64, 64}));
  connect(inertia1.flange_b, torqueStep1.flange) annotation(Line(visible = true, origin = {55.828, -15}, points = {{-10.828, 0}, {10.828, 0}}, color = {64, 64, 64}));
  connect(speedSensor1.flange, smpm.flange) annotation(Line(visible = true, origin = {20, 2.5}, points = {{5, 17.5}, {0, 17.5}, {0, -17.5}, {-5, -17.5}}, color = {64, 64, 64}));
  connect(inverter.ac, terminalBox1.plugSupply) annotation(Line(visible = true, origin = {-18.333, 15.403}, points = {{-46.667, 8.597}, {23.333, 8.597}, {23.333, -17.194}}, color = {10, 90, 224}));
  annotation(experiment(StartTime = 0.00, StopTime = 5, NumberOfIntervals = 5000, __Wolfram_Algorithm = "dassl", Tolerance = 1e-6, __Wolfram_SynchronizeWithRealTime = false), Diagram(coordinateSystem(extent = {{-150, -90}, {150, 90}}, preserveAspectRatio = true, initialScale = 0.1, grid = {5, 5})));
end InverterSMPM;

  • 一种设置是：JLoad=0 和 TLoad=0

    我希望电机能够以怠速自由运行。相反，速度传感器显示幅度为 [-0.46;0.46] 的正弦波

  • 另一个设置：JLoad=0.29 和 TLoad=-180

    当我应用转矩阶跃时，电机的速度 = 0 并且从 t = 2s 开始减小并获得负值。

有人可以告诉我我的模型做错了什么以及为什么模拟结果是错误的吗？

我还尝试了图书馆中的一些示例，但它们从未将逆变器与电机一起使用。但我想研究 PWM，不想像示例中那样使用理想的正弦电压和电流......

感谢您的任何帮助！！

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1 回答 1

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您在模型中尝试做的是让同步电机直接从静止状态以标称电频率运行。这会使机器“失步”，这就是机器无法按预期运行的原因，而只是以看似随机的方式振荡。

尝试降低sine[*].freqHz到fill(0.01*f1, m)，你会看到它会在一些振荡之后开始以标称频率的百分之一运行。只是机器无法克服跳到标称频率的振荡。

有多种解决该问题的可能性：

  1. 正确初始化机器：这可以通过至少设置正确的值smpm.wMechancial.start来完成。smpm.phiMechancial.start此外，最好也正确初始化相电流。这可能非常乏味。但它的优点是您不必提高速度。
  2. 复制示例的部分内容可能更容易Modelica.Electrical.Machines.Examples.SynchronousInductionMachines.SMPM_Inverter，其中使用电压频率控制器来启动机器。
  3. 许多同步电机实际上是受控的（例如通过磁场定向或直接转矩控制）。为此，可以从Modelica.Electrical.Machines.Examples.SynchronousInductionMachines.SMPM_CurrentSource和中获取一些线索Modelica.Electrical.Machines.Examples.SynchronousInductionMachines.SMPM_VoltageSource。

此外，我建议首先尝试让您的示例使用类似 in 的连续逆变器运行Modelica.Electrical.Machines.Examples.SynchronousInductionMachines.SMPM_Inverter。如果按预期工作，请继续切换。

一些在我看来可疑的事情：

  • smpm.Rs4.7 欧姆对我来说似乎相当大，尤其是考虑到惯性smpm.Jr（0.29 kg.m2）和inertia1.J（0.29 kg.m2）。
  • 为了测试，尝试将开关频率提高到 1kHz 以上。这对于 50Hz 的基波频率来说有点低（尽管它应该可以工作）。
于 2019-09-09T15:17:22.837 回答