Alternating Current (AC) power supply is used for almost all the residential, commercial and industrial needs. But the biggest issue with AC is that it cannot be stored for future use. So AC is converted into DC and then DC is stored in batteries and ultra-capacitors. And now whenever AC is needed, DC is again converted into AC to run the AC based appliances. So the device which converts DC into AC is called Inverter. The power inverter is used to convert DC to variable AC. This variation can be in the magnitude of voltage, number of phases, frequency or phase difference.
According to the output characteristic of an inverter, there can be three different types of inverters.
- Square wave inverter
- Pure sine wave inverter
- Modified sine wave inverter
Square wave inverter
The output waveform of the voltage for this inverter is a square wave. This type of inverter is least used among all other types of inverter because all appliances are designed for sine wave supply. If we supply square wave to sine wave based appliance, it may get damaged or losses are very high. The cost of this inverter is very low but the application is very rare. It can be used in simple tools with a universal motor.
Pure Sine wave inverter
The output waveform of the voltage is a sine wave and it gives us a very similar output to the utility supply. This is the major advantage of this modified sine wave inverter because all the appliances we are using, are designed for the sine wave. So, this is the perfect output and gives guarantee that equipment will work properly. This type of inverters is more expensive but widely used in residential and commercial applications.
Modified sine wave inverter
The construction of this type of inverter is complex than simple square wave inverter but easier compared to the pure sine wave inverter. The output of this inverter is neither pure sine wave nor the square wave. The output of such inverter is the some of two square waves. The output waveform is not exactly sine wave but it resembles the shape of a sine wave.