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Electrical Drive Modeling through a Multiphysics System Simulation Approach //
The drive is modeled by a DC circuit, a three-phase inverter based on IGBT
switches, controlling a DC brushless motor. A thermal cooling system and
the control system are simulated along with the power electronics. DC parts
can be modeled by an ideal source or a battery model. The whole system is
shown in the Figure 7.
Following inverter modeling, the control system model can be put in place
using Ansys SCADE Suite. This tool offers the ability to integrate and test
in an analog system flow the actual embedded code that will be loaded in
the final hardware target. SCADE Suite enables automatic generation of a
certified code through a comprehensive graphical interface (Figure 8).
The control can be done with an open loop in the first step and then in
closed loop at a final stage. Electrical control is done through measuring the
return current and mechanical data, such as rotor position, speed and motor
torque. To capture rotor position, Hall effect sensors can be used (Figure 9).
These are modeled f rom lumped elements f rom Simplorer library; they also
can be modeled via ROM for more accuracy f rom 2-D/3-D Ansys Maxwell
software, a general-purpose finite element electromagnetic simulation tool.
The benefits f rom using ROM instead of cosimulation technology (when
physics allow) include a drastic reduction in time simulation without loss
of accuracy compared to high-fidelity field results. The analog information
f rom the sensors is then converted into numerical data and sent back to the
control model f rom SCADE Suite.
Figure 6. Transient simulation example of trial #12 and
temperature field covering whole system.
Figure 9. Position sensors modeling includes analytical
native model and ROM from Maxwell.
Figure 7. Complete drive system simulation with Simplorer.
Figure 8. SCADE Suite for embedded software models the control.
