The modified sine wave is relative to the sine wave. The output waveform of the mainstream inverter is now the modified sine wave. The waveform of the inverter is mainly divided into two types, one is a sine wave inverter (that is, a pure sine wave inverter), and the other is a square wave inverter. The output of the sine wave inverter is the same or better sine wave AC power as the grid we use daily, because it does not have electromagnetic pollution in the grid.