Three-Phase Constant-Current Source Using Immittance Converter

Abstract

The immittance converter is the combined word for the impedance-admittance converter. The immittance converter has an input impedance that is proportional to the admittance of the load connected across output terminals. 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 the switching frequency, and is not suitable for power electronics applications. So we proposed immittance converters that consist of lumped elements L, C and show improved immittance conversion characteristics at a resonant frequency.
A three-phase constant current source is proposed in this paper. It is possible to realize this by a simple circuit using an immittance converter. In this paper, circuit operation, characteristic equations and results of simulation are described.