| US 7,456,695 B2 | ||
| Apparatus, method and computer program product for tracking information in an electric grid | ||
| Haiqing Weng, Shanghai (China); John D. D'Atre, Salem, Va. (US); Robert A. Seymour, Roanoke, Va. (US); Allen M. Ritter, Roanoke, Va. (US); Xiaoming Yuan, Shanghai (China); Renchang Dai, Shanghai (China); and Robert W. Delmerico, Clifton Park, N.Y. (US) | ||
| Assigned to General Electric Company, Schenectady, N.Y. (US) | ||
| Filed on Jan. 10, 2006, as Appl. No. 11/329,248. | ||
| Prior Publication US 2007/0159265 A1, Jul. 12, 2007 | ||
| Int. Cl. H02H 7/09 (2006.01); H02P 9/10 (2006.01) | ||
| U.S. Cl. 331—44 [322/17; 323/205] | 9 Claims |
| 1. A cross-coupled phase-lock-loop filter (CCPLL) for tracking a signal of an electric grid, the CCPLL comprising:
a plurality of PLL filters, wherein an input for a first PLL filter in the plurality of PLL filters comprises the signal of
the electric grid minus an output signal from at least a second PLL filter in the plurality of PLL filters
wherein the first PLL filter comprises:
a synchronous frame phase-lock-loop circuit comprising a d-axis signal output and a q-axis signal output, wherein at least
one of the d-axis signal output and the q-axis signal output are coupled to at least one signal filter, and an output of the
at least one signal filter is further coupled to a circuit for providing a reverse-transformation of the output of the at
least one signal filter to provide a reverse transformation signal.
|