Simple and efficient generalized scalar PWM algorithm for VSI fed induction motor drives

This paper presents a generalized scalar PWM approach for three-phase, two-level VSI based induction motor drives, which unites the various discontinuous PWM (DPWM) and space vector PWM (SVPWM) algorithms. The generation of pulse pattern for various PWM algorithms via the generalized scalar approach is explained in detailed. As the proposed algorithm uses voltages only for generation of modulating waves and hence pulse pattern, this approach is easier for implementation. In this algorithm, a zero sequence voltage is added to the phase voltages, in which by varying a constant (k_o) value between 0 and 1 all DPWM and SVPWM algorithms are derived. To verify the proposed generalized scalar approach, numerical simulation studies have been carried out using Matlab-Simulink. Moreover, the proposed generalized scalar approach is implemented on a dSPACE DS1104 controller board and then compared with the simulation results.