Abstract:
A dual two-level inverter with an open-end
winding induction motor can realise a three/four level voltage
space vector. High switching frequency coupled with the use of
such multilevel inversion system can produce good motor drive
performance. This however can generate immense machine shaft
voltage and bearing currents apart from large leakage ground
currents that are deleterious to the motor drive system and add to
the malfunctioning of many safety equipment. To circumvent the
above problems, this work presents the design and development
of a single common mode (CM) passive filter for the above power
circuit. With the application of the suggested single CM filter,
both the bearing currents and the common mode currents are
successfully attenuated. The proposed CM filter requires less
hardware compared to the use of two CM filters reported in
the literature. Simulations using MATLAB/Simulink is used to
demonstrate the efficacy of a single CM filter. Also, the single
CM filter is experimentally verified with an open-end winding
motor fed from two inverters on both sides
