Apparatus and method for extracting impedance parameters of three-phase motor

A non-transitory computer-readable recording medium containing program instructions executed by a processor, the computer readable medium comprising:

• program instructions that connect two terminals, selected from among first to third winding wires and opposite shaft ends of a three-phase motor, to an input terminal and an output terminal in order to measure voltage and current of the two terminals and to extract input impedance parameters of a five-terminal network;
• program instructions that extract conversion parameters comprising voltage and current transfer matrices in a common mode, in which the first to third winding wires are commonly connected to the input terminal and the output terminal, and in a differential mode, in which the first to third winding wires are differentially connected to the input terminal and the output terminal;
• and
• program instructions that calculate impedance parameters in a mixed mode, in which transfer impedance components for the opposite shaft ends in the common mode and the differential mode are mixed, using the input impedance parameters and the conversion parameters, extracted at the steps of connecting the two terminals and extracting the conversion parameters.

An apparatus for extracting impedance parameters of a three-phase motor constituted by a five-terminal network having first to third winding wires and opposite shaft ends, the apparatus comprising:

• a measurement unit for connecting two terminals, selected from among the first to third winding wires and opposite shaft ends of the three-phase motor, to an input terminal and an output terminal in order to measure voltage and current of the two terminals;
• a parameter extraction unit for extracting input impedance parameters of the five-terminal network and conversion parameters comprising voltage and current transfer matrices in a common mode, in which the first to third winding wires are commonly connected to the input terminal and the output terminal, and in a differential mode, in which the first to third winding wires are differentially connected to the input terminal and the output terminal;
• and
• a parameter calculation unit for calculating impedance parameters in a mixed mode, in which transfer impedance components for the opposite shaft ends in the common mode and the differential mode are mixed, using the input impedance parameters and the conversion parameters, extracted by the parameter extraction unit.