The pulse width modulation wave is generated because the main factors affecting the price of UPS are efficiency and volume. If the conversion efficiency is low, complicated heat dissipation measures must be adopted. If the working frequency is low, a filter with a large filter coefficient must be adopted. The chokes and capacitors used for filtering are very heavy and expensive. The high frequency operation of pulse width modulation technology effectively solves the above-mentioned problems. Here, the combined action of triangle wave and sine wave is used to generate pulse width modulation wave. As shown in Figure 5(b), it is a comparator that compares a triangular wave with a sine wave. It can be seen from the figure that the sine wave signal is added to the non-inverting input terminal (+) of the comparator, and the triangular wave is added to the inverting input of the comparator. end(-). Figure 5(c) shows the principle of pulse width modulation wave formation. When the envelope of the sine wave is higher than the triangle wave, the comparator outputs a positive pulse, otherwise, it outputs 0. The principle and process of the negative half wave are exactly the same as the positive half wave, so it is not repeated. In this way, the complex sine wave output voltage generation process has become a simple high-frequency constant-amplitude pulse-width modulation wave. At the same time, the work of the inverter has been simplified, and since then the UPS has entered a new stage.

Please kindly take a view and better to understand us:

inverter with limiter