| 摘要 |
PROBLEM TO BE SOLVED: To accurately detect a phase of an input signal while reducing influence of unbalanced components and harmonic components.SOLUTION: A phase detection device 10 comprises: a fundamental wave orthogonal component calculator 10A that includes a three-phase to two-phase converter 11 to convert three-phase voltage signals v, v, vinto voltage signals vα, v&bgr; orthogonal to each other, a fundamental wave extractor 12 to extract a fundamental wave component from the voltage signals vα, v&bgr; by use of the following specified matrix, and a normalizer 13 to normalize signals outputted from the fundamental wave extractor; and a PLL processor 10B to cause a phase &thetas;' to converge into a phase &thetas; by use of voltage signals (sin(&thetas;),cos(&thetas;)) (&thetas;: phase of an input signal) output from the fundamental wave orthogonal component calculator 10A. |
