Method and apparatus for power inverter synchronization
US7183667B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 2003 |
| Grant date | Feb 27, 2007 |
| Priority date | — |
| Expiry date | Apr 19, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M1/0012
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A control circuit synchronizes an ac power inverter to the mains voltage of an electrical grid by matching the fundamental phasor components of the inverter's output voltage to the fundamental phasor components of the mains voltage. Once such matching meets an acceptable voltage error threshold, the control circuit initiates contactor closure, verifies contactor closure, and then initiates a changeover from voltage-mode control used in synchronization operations to a current-mode control of the inverter's output. The control circuit provides corresponding disconnection control when disconnection from the grid is desired, wherein the regulated power of the inverter is ramped down in controlled fashion until it reaches a lower threshold whereupon contactor opening is initiated. Once contactor opening is verified, regulation control reverts to stand-alone voltage mode control or to shut down, as needed or desired.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.