A METHOD TO MEASURING IMPEDANCES AND TIME CONSTANTS OF SYNCHRONOUS MACHINE UNDER OPERATING CONDITION

摘要

A method to measuring impedances and time constants of synchronous machine is presented in this paper, which is different from those suggested by some authors. Small periodic disturbances, which are imposed on excitation controller , make the generator deviate from steady state, and, using linearized model of synchronous machine in the form of FOURIER transform, the operational impedance and time constants are calculated from the data of voltage, current and rotor angle of the generator, which are recorded by the computer aided test equipment during dynamic process, small periodic excitation disturbance make the test to be carried out conveniently and increase the signal to noise ratio, and result in more accuracy test results more suitable to study dynamic stability. The results for a model generator are presented in this paper, and conventional tests were carried out also. They show good agreement with the new method.