Multilevel inverter technology has emerged recently as a very important alternative in the area of high-power medium-voltage energy control. Multilevel inverters include an array of power semiconductors and capacitor voltage sources, the output of which generate voltages with stepped waveforms. These inverters promise a lot of advantages over conventional inverters especially for high power applications. Some of the advantages are that the output waveforms were improved since multilevel inverter produced nearly sinusoidal output voltage waveforms. Hence the total harmonic distortion is also low. The switching losses also become less. And, the filter needed to smooth the output voltage is small; hence, the system is compact, lighter and much cheaper. In this paper, a modified single phase seven level inverter is simulated using MATLAB Simulink. Three reference signals that are identical to each other with an offset that is equivalent to the amplitude of the triangular carrier signal were used to generate the PWM signals. The inverter is capable of producing seven levels of output-voltage levels (Vdc, 2Vdc/3, Vdc/3, 0, -Vdc, -2Vdc/3, -Vdc/3) from the dc supply voltage.