Comparative analysis of space vector and sinusoidal pulse width modulation based single phase inverters

In this study, two different Pulse Width Modulation (PWM) techniques required for the control of power switches of single-phase inverters are compared. Space Vector Pulse Width Modulation (SVPWM) and Sinusoidal Pulse Width Modulation (SPWM) are among the techniques commonly used in the control of power switches of inverters. The reasons for the widespread use of these two techniques in inverter structures are that the mathematical equations are not complicated, smaller dimensions of the system, fewer switching losses and fewer Total Harmonic Distortion (THD) values which is an important parameter in inverter control. The sinusoidal signal produced by the Quasi Z-source converter is connected to the inverter switched using the SPWM technique, and a sinusoidal signal is obtained at the output of the inverter without using a filter. In order to reduce THD and to generate a pure sinusoidal voltage signal, a circuit is constructed using two power switches, two capacitors and two inductors in the Quasi Z-source converter block. When inductive and capacitive loads are examined, the fact that they produce pure sinusoidal current and voltage waves shows that the voltage and current signals at the inverter output nodes are positively affected by THD. SVPWM, on the other hand, is a PWM technique that includes superior performance and advanced intense mathematical equations. The steps applied to minimize the switches losses of the inverter which are driven by the SVPWM technique are done through conversion into a single-phase shape with the Clarke transform theorem. Four sectors were defined with ninety degrees. By taking alpha and beta angles as the references, mathematical equations were created in such a way that sine waves were formed in four sectors. An LC filter was used to make the voltage and current signals sinusoidal and positively affect THD. The two proposed theorems were verified by checking their mathematical models with MATLAB Simulink. When the two methods are compared, the THD value of the voltage at the output of the inverter controlled by the SVPWM technique is 2.20%, and the voltage THD value at the output of the inverter controlled by the Quasi Z-source converter and the SPWM technique is 2.13%. When the input direct current value of the compared inverters is 240 Volt, the frequency is 50 Hz and the modulation index is approximately 0.75, two loads are connected to the outputs and the changes in the shapes of the voltage and current signals are observed. When the second load was added, no change was detected in the voltage signals, while a double increase was observed in the current signals.