## 4 Confirmation from Simulated and Practical Results
### Verification with Practical Results  
The practically obtained results are more valuable than the simulation results because they include real-time limitations that may not be presented in the values obtained from other plate forms, such as simulation and mathematical results. The practical setup consists of eight diodes (MUR3040) with low reverse recovery times in the nanosecond range. These diodes have voltage and current ratings of 400 V and 30 A, respectively. Four high switching speed IGBTs (IXGH 40N60C2) were used as active switching transistors to operate at 20 kHz to 25 kHz switching frequency successfully. These transistors have voltage and current up to 500 V and 75 A, respectively. There are four operating transistors, of which two operate at low frequencies, and their reference point is not at ground voltage level (floating). In contrast, the reference terminals of the high-frequency switching transistors are connected to the ground voltage level. Therefore, the difficulty level of the low and high-frequency operating devices is not the same. This issue was tackled by using four similar gate drive circuits realized with four hybrid chips (EXB840) to avoid any possible miss operation of any transistor, whether it is a low or high-frequency operating transistor. A load of 150 \(\Omega\) impedance was selected for the safe operation of the converters. An inductor of 1 mH was used in series with the load to store the energy from input and deliver to load in the on and off PWM intervals, respectively. Two capacitors, 2.2 \(\mu\)F and 4.7 \(\mu\)F, were connected across the input and output terminals to ensure and maintain the power quality parameters within an acceptable range. These values are designed in Section 2.3 by following the design procedure stated in [24]. The plots of Figure 7a,b represent the non-inverted and inverted forms of the output voltage. The maximum value of the voltage at the output is nearly 50 V with a given peak of input voltage of 170 V. The generation of the control signals may be produced from a microcontroller (STM controller or Arduino controller) or microprocessor. The voltage bipolar behavior of the output is also validated in Figure 7c, where the output frequency was adjusted to one-half of the input frequency. It is clear from the observation of  
Figure 6: Simulation waveforms of output voltage (blue) with respect to input voltage (red) for the voltage gain of 0.5: (**a**) voltage in-phase form; (**b**) voltage out-of-phase form; (**c**) frequency regulation form.  
this figure that the first and fourth pulses are in-phase with the line voltage, but the second and third pulses are out of phase. This pair of pulses means first-forth and second-third show input voltage conversion into non-inverting and inverting forms. In Figure 7, the peak value of the output voltage was kept at less than half the value of the maximum input voltage. The plots of Figure 8a-c explore the similar behavior as represented in Figure 7, except that the peak value of all output pulses, which are approximately 100 V, is greater than half of the maximum value of the source voltage. It was confirmed from the plotting of these all waveforms that the magnitude or rms value of the output voltage can be adjusted between the zero and maximum output voltage. This is ensured with high-frequency switching, but its effect is not reflected on the output side as there is the use of a series inductor and parallel capacitor across the output terminal. The output frequency can also be changed to some selected output frequencies.  
Figure 7: Recording of output waveforms (blue) with respect to input voltage (red) with a voltage gain of 0.3: (**a**) voltage in-phase form; (**b**) voltage out-of-phase form; (**c**) frequency regulation form.