(0091) Control of Open end Induction Motor by Multi-objective GA based Selective Harmonic Elimination PWM to reduce Zero Sequence Currents and Torque Ripples
A double inverter powered induction motor with open stator winding has a number benefits, including excessive error forbearance functionality, great flexibility and lower rating of DC input voltage. For this configuration, two types of modules can be implemented: non-isolated DC link and isolated DC link. In these two, non-isolated DC link is a good choice due to effective DC-link utilization and ruggedness, which is very beneficial in many applications. However, this module produces more zero sequence currents (Z-SC) by means of common mode (CMMD) voltage, which flows through DC bus. The circulation of Z-SC must as low as feasible, since it merely increases the amplitude of currents in all phases. High ripple frequency of currents and torque, in addition, results in extra loss, which reduces efficiency and loading ability and accelerates the aging of the drive. Triplen harmonics can denote meticulously as harmonics with integer of three times the frequency at fundamental, when they are in phase in all phase forms the Z-SC.?? In this paper, a novel SHE method is chosen to target triplen harmonics in a Single DC Source Module (non- isolated) and holding preferred fundamental quantity, which aids in improving the torque handling ability of the motor. In addition, the paper reports on the investigation of dual inverter fed OEW-IM with both common DC source as well as separate DC sources, also explored by SHE for different numbers of switching angles and variable Modulation Index (MI) towards the torque ripples and Z-SC reduction. The primary challenge related to the SHE method is that of resolving a set of higher order nonlinear equations with a number of variables. A multi-objective GA method addresses that challenge, reducing Z-SC so that torque ripples will be minimized. Moreover, the novel SHE method reduces a greater number of harmonics than the conventional SHE, which further decreases TH-D. For validation, the key mathematical formulations and simulation results are presented.