Variable speed gensets (VSG) power electronics technology enables generators to operate much more efficiently than fixed speed units because the optimum speed-torque point of the engine can be matched with the output power needs of the load.
Key applications for VSGs
VSGs are used in applications with low average power requirements, such as those with cyclic loads, occasional motor starting, extreme non-linear loads or other power quality sensitive applications. They are also used in grid tied applications where power control can simplify grid interconnection.
VSGs can stabilize the voltage and frequency of the grid, allowing the engines to run at a lower speed. An output step response can also be achieved by combining energy storage with VSG power electronics.
The main benefits of VSGs are fuel savings, emission and noise reductions, and extended engine life. In the future, VSGs will also establish themselves in the uninterruptible power supply (UPS), peak shaving and VAR markets, where their capital cost compares favorably with the current alternatives.
VSG systems make most economic sense in applications with low average power demands – such as cranes that require full power for only short periods of time while lifting.
Advantages of The Switch VSGs over fixed speed units
- Average fuel savings of 20 – 50%
- Reduced emissions as fuel is burned more cleanly
- Reduced noise and vibrations (>6 dB)
- Decreased engine wear – time to overhaul can be doubled
- Optimum engine sizing: engine can be sized according to average load requirement,
with peak loads supplied from electrical energy storage unit