Analytical Fourier Approximation of Voltage Space-Vectors in Three-Level Space-Vector Modulated Voltage Source Inverters

This paper proposes an analytical model for calculating of the harmonic spectra of a three-level voltage source inverter (VSI) with space-vector PWM (SVPWM).A three-level inverter has a large number of switching states compared to a two-level inverter and, therefore ,the SVPWM algorithm is more complex. The proposed model is based on the Laplace transform of the voltage space vectors in the complex a-beta plane. From the analytical relations we can visualize the derived Fourier series both in the complex plane and/or in the real phases by means of the programme MATCAD.