What is the difference between power frequency inverter and high frequency inverter?

Power frequency and high frequency inverter load comparison

The power frequency of the inverter with the same power is heavier than that of the high-frequency inverter. The high-frequency inverter has a smaller, lighter, higher efficiency and lower no-load, but it cannot connect to the inductive load with full load, and its overload capacity is relatively poor.  
 
Contrast the basic principle of power frequency and high frequency inverter

The high frequency circuit is relatively complex, and the high frequency inverter is composed of igBT module high frequency rectifier, battery converter, inverter and bypass.  Igbt module with the help of control plus in the gate drive to control its on and off, power off, IGBT module rectifier control switch frequency mostly in a few kilohertz to dozens of kilohertz, or even hundreds of kilohertz, far higher than the power frequency inverter, so it is called high frequency inverter.  
 
Power frequency inverter is designed based on the traditional analog circuit principle, which is composed of thyristor (SCR) rectifier, IGBT inverter, bypass and power frequency boost isolation transformer.  So the rectifier and transformer working frequency are power frequency 50Hz, also known as power frequency inverter.  

 
Comparison of conversion efficiency between power frequency and high frequency inverters

Power frequency inverter is not as efficient as high frequency inverter, because the complex hardware analog circuit is burned in the microprocessor, to control the operation of the inverter in the way of program.  In addition to the large size of the high-frequency inverter reduction, its conversion efficiency is also improved.