Normal mode
In normal mode, the reactor and generator function as an active filter that prevents any disturbance from the utility reaching the critical load. The generator runs as a motor and drives the induction coupling, storing kinetic energy in the inner rotor.
Power outage
In case of power interruption, the mains circuit breaker opens. The kinetic energy in the induction coupling is used to maintain constant generator speed. Simultaneously, the diesel engine starts. Within 10 seconds the diesel engine is the sole provider of power to the load.
Diesel mode
The diesel engine powers the load and restores the kinetic energy level in the induction coupling. Also in diesel mode the output voltage and frequency is kept without tight tolerances. The induction coupling is used to support the diesel engine during loadsteps.
Mains power returns
Once the mains power has stabilized, the UPS synchronized with the mains and closes its mains circuit breaker. The diesel engine continues to run for a short time to cool down before it shuts down and returns to standby mode. |
