METHOD AND DEVICE FOR MEASURING HIGHER HARMONIC BY CAPACITANCE POTENTIAL DEVICE

摘要

PROBLEM TO BE SOLVED: To enable the highly accurate calculation of a primary-side higher harmonic at any point in time by obtaining the transmission circuit constant of every order of each higher harmonic of a capacitance potential device in advance and using the same. SOLUTION: A CPU 14 operates to obtain E1 (n) through the use of PD constantsα(n) andβ(n) and measurement data E2 (n) stored in memory 15 in advance. The higher harmonic E2 (n) of each n-order harmonic is obtained by subjecting a measured secondary voltage to FFT processing. Further, the CPU 14 prints E1 (n) up to a predetermined order to a printer 17 via an interface 16 and graphically outputs its spectrum strength as necessary. A clock circuit 18 times the present date and time. The CPU 14 performs a predetermined number of sampling at predetermined timing according to the timing of the clock circuit 18 and automatically and sequentially performs harmonic analysis. Therefore, it is possible to measure a primary-side higher harmonic simply and accurately even with changes in systems and burdens.