Abstract: The equivalent conversion equation between passive star circuit and polygon circuit is derived in a simple way. It is proofed that a polygon circuit or an imperfect polygon circuit has a unique equivalent star circuit. Examples are given to show the application of the equivalent conversion equation between passive star circuit and polygon circuit. The equivalent conversion method between imperfect polygon circuit and star circuit is introduced. Furthermore, the method is given to separate the equivalent current source of active star circuit and polygon circuit from passive starcircuit and polygon circuit.

Key words: equivalent conversion, multi-terminal network, star-polygon transformation