Abstract
Characteristics of 2-phase servomotors can be analyzed by the use of an equivalent circuit. The method for measuring equivalent circuits is based on zero speed tests and synchronous speed tests, that is, measuring the input impedance, first with the rotor locked, and then with the rotor circuit open. In the former measurements, the secondary voltage must be kept constant considering saturation of the core. By additionally measuring the input power at zero speed and the d-c resistance, it is possible to determine the equivalent-circuit constants with the aid of the nomograph in which the relationship between measured values and circuit constants are expressed graphically.
To check the accuracy of the above method, we compute various characteristics and compare with the measured results. This method of obtaining equivalent-circuit constants was found useful, and computed results are sufficiently accurate.
