PURPOSE: To determine a phase difference between phases of a current signal accurately, by calculating and displaying an absolute phase of quantity of electricity between data at a specified sampling time and a time preceding by a specified time therefrom.
CONSTITUTION: A central processing unit calculates and displays an absolute phase α of a quantity of electricity at a specified time between a first data v0 at a specified sampling time pertaining to a certain one quantity of electricity and a second data vt at a time preceding by a known nT from the specified sampling time. Thus, even when the absolute phase of a voltage signal va as reference is unstable, after being calculated, the absolute phase per current signal is compensated by that of the electrical signal va as reference corresponding to the said individual phase, thereby enabling accurate determination of a phase difference between phases of a current signal.
WO/2001/050144 | PHASE DETECTOR |
JPS59107275 | DETECTING CIRCUIT OF PHASE DIFFERENCE BETWEEN AC VOLTAGE AND CURRENT |
JPS5456481A | 1979-05-07 | |||
JPS5015664A | 1975-02-19 |