To provide a method and a device, capable of finding, simply and accurately, load admittance Yn and a load-side current-source current Ign of a power distribution system.
In this measuring method, first, a proportionality constant αn expressing a relation between harmonic-wave conductance gn and fundamental-wave conductance g1 of a distribution system, a correction value βn for higher harmonic-wave susceptance bin of the Inoue model, a proportionality constant γn expressing a relation between the amplitude of a load-side current-source current Ign and a fundamental-wave current, and an average value δn of phases of the load-side current-source current Ign, are found by performing fundamental wave measurement and harmonic wave measurement (step 50). Next, a fundamental-wave voltage V1 and a fundamental-wave current I1 of the distribution system are measured (step 51), and load admittance Yn and the load-side current-source current Ign, the object of measurement, are found by performing operations of steps 52 to 62 according to a load characteristic equation, by using the measured V1 and I1 as well as the constants and values, αn, βn, γn, and δn.
SAWADA TAKAYOSHI
NISHIMURA SOJI
SHIKATA TOSHIHIKO
NISSIN ELECTRIC CO LTD