Synchronisation and parallel operation

Connecting a generator to a busbar or to the grid, and operating multiple generators in parallel, requires precise control over voltage magnitude, frequency, and phase angle differences. Sync-check (ANSI 25) supervises a manual or external auto-sync attempt; auto-sync controller (ANSI 25A) actively drives the generator's speed governor and AVR until the closing window is reached and then issues the breaker close command.

SYMAP^® Y-G, BCG and ECG provide synchronisation and parallel-operation functions as part of generator protection. Compact+ GC covers the single-unit grid connection case with check-sync and auto-sync. For full multi-generator PMS with load sharing and bus-tie logic, classic BCG / ECG remains the choice.

Typical applications

Sync-check (ANSI 25)

Supervises a manual or external auto-sync attempt. Checks slip, voltage magnitude difference and phase angle within set windows; issues a permissive signal to close the breaker.

Auto-sync controller (ANSI 25A)

Active synchronisation: drives the diesel governor (speed) and AVR (voltage) until the closing window is reached, then issues a breaker close command. Closing angle compensation for breaker dwell time.

Generator-to-busbar synchronisation

Synchronising a generator onto an energised busbar in a marine PMS, offshore platform or generation plant. Coordinated with PMS load sharing and bus-tie logic.

Generator-to-grid synchronisation

Synchronising a single generation unit to the utility grid. Grid Code compliance (VDE-AR-N 4110/4120, G99), EZA/EZE controller logic, FGH certificate documentation.

Bus-coupling synchronisation

Synchronisation across an open bus-tie breaker between two energised bus sections. Critical for DP-class redundant power architectures and bus-section transitions.

Marine parallel operation

Marine PMS with multiple generators in parallel. Load sharing (active and reactive), automatic load shedding, bus-tie logic, blackout prevention, SYMAP^® BCG and ECG.

Compact+ or classic SYMAP^®?

SYMAP^® Compact+ GC covers single-unit grid connection with sync-check and auto-sync (ANSI 25, 25A). For systems with multiple generators in parallel operation, load sharing, automatic load shedding and bus-tie logic, classic SYMAP^® BCG / ECG with full Power Management System remains the choice.

Products covering this application

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Synchronisation and parallel operation