Starting the asynchronous motor according to the "star-triangle" scheme
This example will demonstrate a model simulating the start of an asynchronous motor with a squirrel cage according to the "star-triangle" scheme (model induction_machine_starting.engee).
This example shows how to simulate a star-triangle trigger circuit for an asynchronous machine. When power is connected to the machine via switch S1, switch S2 is initially turned off, resulting in the machine being connected via a star circuit. As soon as the machine approaches synchronous speed, switch S2 is triggered, thereby reconnecting the machine in a triangle configuration. The star-triangle asynchronous motor start-up circuit provides small currents in the network during start-up, and after the motor reaches the speeds necessary for its operation, it switches to the triangle circuit, which allows it to operate at 100% load without any problems.
General view of the models
The Engee model:
Implementation of the model launch using software control:
Downloading the necessary libraries:
using Plots
gr();
using DataFrames
Loading the model:
model_name = "induction_machine_starting"
model_name in [m.name for m in engee.get_all_models()] ? engee.open(model_name) : engee.load( "$(@__DIR__)/$(model_name).engee");
Launching the uploaded model:
results = engee.run(model_name)
Reading data on instantaneous load current values and shaft rotation speed:
t = results["i_a"].time;
i_a = results["i_a"].value;
i_b = results["i_b"].value;
i_c = results["i_c"].value;
w = results["w"].value;
Downloading and visualizing the data obtained during the simulation
plot(t, [i_a i_b i_c], label=["Ток фазы А" "Ток фазы В" "Ток фазы С"])
plot!(ylabel = "Мгновенное значение тока, А", xlabel="Время, c")
plot(t, w, label="Скорость вращения вала")
plot!(ylabel = "Скорость вращения, об/мин", xlabel="Время, c")
Conclusions:
In this example, tools were used for command control of the asynchronous motor start model. The simulation results were imported into a script and visualized using interactive graphs from the Plots library.