The immittance converter has the input impedance that is proportional to the admittance of the load connected across output terminals. Therefore, in this converter, the output current is proportional to the input voltage and the input current is proportional to the output voltage. Consequently, it converts a constant voltage source into a constant current source and a constant current source into a constant voltage source.
It is well known that the quarter-wavelength transmission line shows immittance conversion characteristics. However, it has very long line length for inverters switching frequency, and is not suitable for power electronics application. So we introduced five types of immittance converters that consist of lumped elements L, C and show improved immittance conversion characteristics at a resonant frequency. After that many types of immittance converter are developed and applied to some applications.
