What is modified sine wave inverter

There are two main types of waveform of inverter. One is a sine wave inverter (pure sine wave inverter). Another one is square wave inverter. A square wave inverter outputs relatively low-quality square wave alternating current, whose positive maximum and negative maximum occur at the same time, causing a drastic effect on the load and the inverter.

To address problems of square wave inverter modified sine wave inverter was invented, the output waveform of which has a time interval between positive maximum and negative maximum, improving its operating function. However, waveforms of modified sine waves is still composed of polylines, which means it’s a kind of square wave that has poor continuity and dead zone ( waveform is as follows ).

(a): square wave
(b): modified sine wave
(c): pure sine wave

Modified sine wave inverters are able to satisfy the electrical demands of most electrical equipment if the demand for electrical quality is relatively low. In addition, the price of the modified sine wave inverter is lower than sine wave inverter and conversion efficiency is higher. However, there exists a 20% harmonic distortion in modified sine wave inverter that may cause problems when operating precision equipment and high frequency interference to communication facilities. We still recommend you to choose pure sine wave inverter if you need to operate precise equipment.