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Modulation of Vector Space Pulse Width (SVPWM) and Sinusoidal Pulse Width Modulation (SPWM) using MATLAB tools. During these investigations, we performed intensive simulations, we analyzed the results widely and compared the harmonic density, power factor (PF) and switching losses of SVPWM and SPWM. During the investigations it has been observed that if the switching frequency is high, losses due to harmonics are negligible, therefore, based on the results obtained, it is suggested that the SVPWM technique is a more reliable solution. Because the SVPWM uses the DC bus voltage more efficiently, it generates less total harmonic distortion (THD) and has a higher output quality, it provides flexible control of the output voltage and the output frequency for the speed unit Variable (VSD). In fact, with the advent of advancement in manufacturing and design, the AC units over-delivered the DC units because of their higher performance and better efficiency.
The most important advantages of AC drives on DC units are a faster predictable dynamic response, a constant and better power factor (PF) and a continuous torque of 100% at zero speed (applicable to vector control technology flow). AC motors are low cost, less complicated, resistant and easy to maintain or replace, so this is also one of the main causes of the technology change from DC units to AC units. For optimum performance, we select the best switching and control technique for AC drives. The control techniques used in variable speed units (VSD) are scalar control (Volts per Hertz Control), vector control (direct torque control and field oriented control) where as the switching techniques used in the unit (SHPWM), delta-pulse width modulation (DPWM), delta-sigma pulse width modulation (DSPWM), minimum ripple current pulse width modulation, and sinusoidal pulse width modulation (SPWM) ), etc.