For the convenience of discussion, just look at the case of a pulse width modulated wave. As shown in Figure 6, when the rated output voltage is set, the reference voltage of the triangular wave is UN, in other words, the triangular waveform is superimposed on a DC voltage UN. Because the feedback signal is needed for stable regulation, this voltage UN is used as the feedback signal when the UPS outputs the rated voltage. At this time, a pulse width modulation wave width as an example is tN. When the output voltage rises, set the negative feedback signal voltage UN to rise to UH, so that the triangle wave voltage has a rising amount:

ΔU=UH-UN (6)

That is to say, when the sine wave at the input of the comparator remains unchanged, the triangular wave shifts upward by ΔU, which will inevitably cause the area where the sine wave is higher than the triangular wave to decrease at this point, and the width of the pulse width modulation wave is reduced from tN to tH, after several processes, the increased voltage returns to the normal value, as shown in the figure. When the output voltage decreases, the reference voltage of the triangle wave decreases, which makes the area of the sine wave higher than the triangle wave larger, and increases the width of the pulse width modulation wave from tN to tL, and after several processes, the reduced voltage returns to the normal value.

Please kindly take a view and better to understand us:

inverter with limiter