CONTROL SYSTEM

摘要

The present invention relates to a control system (1) of active power in a first electric power network (A), which is adapted to obtain power from a second electric power network (B). The first electric power network (A) is connectable to the second electric power network (B) via at least two connection points. Each connection point comprises a frequency converter (21, 22), which is adapted to synchronously convert a second frequency (f2), acting in the second electric power network (B), into a first frequency (f1), acting in the first electric power network (A). There is a phase-angle difference, or transfer angle ( delta ), between the second frequency (f2) at a first connection point (11) and the second frequency (f2) at a second connection point (12). The phase ratio (&phgr;) between the first and second frequencies (f1, f2) at the respective connection point may be set by a control of the frequency converter (11, 12) acting at the connection point. The respective frequency converter (11, 12) is adapted to cooperate with a phase-measuring device (21, 22), which comprises a time reference (31, 32) whereby a common time measurement is possible for the converters and whereby a phase value for the frequency (f2) can be determined in relation to the common time measurement in the respective converter (11, 12). The respective frequency converter (11, 12) may be set at a desired phase ratio through a set value (&phgr;1b, &phgr;2b) for the phase ratio at the respective connection point.