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5.2.1 Changing PWM Frequency

This exercise is intended to change the PWM frequency and observe its impact on the waveforms, THD, and the power flow.
For that, keep all the parameters unchanged except for the slider: PWM Frequency (Hz).

Figure 12: Varying PWM Frequency

Apply the PWM frequency values of the first column of table 9, observe the waveforms, read the displays, and fill out below.

Table 9: Varying PWM Frequency with LC Filter ON

Disable the Connect Filter button and redo the same exercise.

Table 10: Varying PWM Frequency with LC Filter OFF

How does the change of PWM Frequency impact the THD of load and inverter currents?
     Hint: Please observe the values of Display₆ and Display₇.

5.2.2 Changing AC-source amplitude

This exercise is intended to show the impact of changing the amplitude of the AC Source and to observe the source current and the power flow.
Using the slider Amplitude (V), do the following:

Increase the value of the amplitude to 75 V and observe the waveforms and the power flow.

Figure 13: Varying AC-source Amplitude to 75 V

Increase the value of the amplitude to 90 V and redo the same observations.

Figure 14: Varying AC-source Amplitude to 90 V

• Determine the amplitude at which the power flow vanishes.

5.2.3 Changing AC-source phase-shift

This exercise is a repetition of exercise 5.1.2 except that the LC filter is ON.

Repeat the same steps as before.

Figure 15: Varying AC-source Phase-Shift; Load More Inductive and LC Filter On

Figure 16: Varying AC-source Phase-Shift; Load More Capacitive and LC Filter On

What difference do you observe in terms of power flow between Phase-Shift of 60 and -70?