Modelling and Simulation of Autonomous Systems with Voltage Inverters, Output Filters and Asynchronous Motors

This paper presents a new model of control principle for autonomous systems based on asynchronous motors fed by static power converters. All the coefficients required for control are determined by Fourier analysis of the output voltage waveform. The resulting dynamic system model is able to accurately predict the system response. The inverters are used for many modern autonomous systems where the direct current voltage sources, such as lithium-ion batteries, solar panels, or combustion cells, have to be transformed so that the devices can run fed from an alternating current source of variable voltage and frequency. The new methods proposed are verified by simulation, by the analysis of the diagrams of stator voltage, stator current, rotor speed and electromagnetic torque, and by the dynamic behaviour of a real experimental model. A Fourier analysis model identification approach and the reducing of harmonics determine the optimum performances in terms of losses, heat and noise of the induction motor, system or vehicle.