This paper deals with analysis of two-section frequency converter based on two series-connected voltage inverters operating modes. The implementation issue of the vector pulse-width modulation for analyzed convertor is considered. The schemes of inverter switching states and the vector diagram of the output voltage are presented. It is shown that the vector state diagram corresponds to the diagram of the traditional three-level inverter. The proposed algorithm of vector PWM provides a switching frequency doubling of phase voltage with respect to the switching frequency of the power transistors. The presented algorithm of the vector PWM eliminates the necessity to compensate the 2nd and 4th harmonics that occurs when using traditional sinusoidal PWM with asymmetric reference signal. Also this technique slightly improves harmonic composition of the output voltage of the convertor. However additional switching of the zero vector increases the load on the power switches. To implement the presented algorithm is useful FPGA module. The article presents the plot of the phase output voltage of the converter and its spectral composition.