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Thermal scheme of the electric motor

This example demonstrates how the thermal state of a brushless motor can be modeled using a lumped-parameter model. The heat generated due to power losses in the stator, winding and rotor is represented by three sources of heat flow: heat generation in the stator (Q of the Stator), heat generation of the winding (Q of the Winding) and heat generation of the rotor due to losses due to magnetization and eddy currents (Q of the Rotor). The losses were recorded during the simulation of a typical electric motor cycle and stored in blocks Repeating table. The thermal circuit of the engine consists of heat-conducting elements, thermal masses and convective heat transfer units that reproduce the ways of heat propagation in parts: winding, stator, housing, rotor, front and rear bearing supports and flange. The engine exchanges heat with the atmosphere through the contacts housing-atmosphere, flange-atmosphere and bearing 1 -atmosphere. Environmental conditions are simulated using an ideal temperature source set at 300 K.

Model diagram:

motor_thermal_circuit--1733400267958.png

Defining the function to load and run the model:

In [ ]: 
function start_model_engee()
    try
        engee.close("motor_thermal_circuit", force=true) # closing the model
        catch err # if there is no model to close and engee.close() is not executed, it will be loaded after catch.
            m = engee.load("$(@__DIR__)/motor_thermal_circuit.engee") # loading the model
        end;

    try
        engee.run(m) # launching the model
        catch err # if the model is not loaded and engee.run() is not executed, the bottom two lines after catch will be executed.
            m = engee.load("$(@__DIR__)/motor_thermal_circuit.engee") # loading the model
            engee.run(m) # launching the model
        end
end
Out[0]:
start_model_engee (generic function with 1 method)

Running the simulation

In [ ]: 
try
    start_model_engee() # running the simulation using the special function implemented above
    catch err
    end;

Recording temperature and heat flow signals from simout to variables:

In [ ]: 
t = collect(simout["The thermal mass of the stator.T"].time[:])
Температура_ротора = collect(simout["The thermal mass of the rotor.T"].value[:])
Температура_обмоток = collect(simout["The thermal mass of the windings.T"].value[:])
Температура_статора = collect(simout["The thermal mass of the stator.T"].value[:])
Температура_корпуса = collect(simout["Thermal mass of the housing.T"].value[:])
Тепловыделение_ротора = collect(simout["The thermal mass of the rotor.T"].value[:])
Тепловыделение_обмоток = collect(simout["The thermal mass of the windings.T"].value[:])
Тепловыделение_статора = collect(simout["The thermal mass of the stator.T"].value[:]);

Visualization of simulation results

In [ ]: 
using Plots
In [ ]: 
plot(t[:,1], Температура_ротора[:,1], label="Rotor temperature, K", linewidth=2)
plot!(t[:,1], Температура_статора[:,1], label="Stator temperature, K", linewidth=2)
plot!(t[:,1], Температура_обмоток[:,1], label="Winding temperature, K", linewidth=2)
plot!(t[:,1], Температура_корпуса[:,1], label="Case temperature, K", linewidth=2, legend=:bottomright)
Out[0]:
In [ ]: 
plot(t[:,1], Тепловыделение_ротора[:,1], label="Heat dissipation of the rotor, W", linewidth=2)
plot!(t[:,1], Тепловыделение_статора[:,1], label="Stator heat dissipation, W", linewidth=2)
plot!(t[:,1], Тепловыделение_обмоток[:,1], label="Heat dissipation of windings, W", linewidth=2, legend=:bottomright)
Out[0]: