Section 2 General Information; Ecogen Operating Principle; Benefits; How It Works - Generac Power Systems 15 kW EcoGen Owner's Manual

General Information
Section 2
2.1 — EcoGen Operating Principle
2.1.1— Benefits
The 15 kW EcoGen generator brings exciting new technology to the Home Standby generator product. The generator
is significantly more fuel efficient than constant speed generators at normal loads, provides premium power quality, and
is significantly quieter while operating at normal loads.
Quieter operation - 3 dB with improved tonal qualities under normal loads
•
Cleanest Standby power available with 1.5 THD
•
• Significant fuel savings: more fuel efficient under normal loads
Lower operating speed at 2700 rpm at low loads
•
• Tuned exhaust system to further lower sound levels
• Variable Speed / Constant Frequency operation
2.1.2— How It Works
In an off-grid solution, the generator is an important source of backup power when other resources are insufficient for
the demand, improving overall system reliability.
Sun (solar cells) and/or wind (turbines) generate DC current.
1.
This is fed to the inverter charger and then on to the battery bank.
2.
The inverter takes DC power from the battery bank, converts it to AC and then sends the current to the AC elec-
3.
trical panel.
If there is no solar or wind gain and the battery bank level drops below a preset threshold, the inverter automati-
4.
cally signals the generator to start up.
The generator feeds AC power to the inverter, which in turn sends power to the electric panel and recharges the
5.
battery bank to an acceptable level.
2.1.3— Start-up
When the generator starts up, the engine ramps up to 3600 RPM to produce maximum power. This ensures that there
is sufficient power to carry the load on start-up. The engine RPM then gradually ramps down to a speed appropriate for
the attached load.
For example, if there is no load, the engine ramps down to approximately 2700 RPM. The time it takes to ramp down to
2700 RPM is approximately 4-5 minutes. Since the ramp rate is linear, less time would be required for it to ramp down
to only 3400 RPM.
During startup, as the engine ramps up to 3600 RPM, the Automatic Voltage Regulator (AVR) electronics performs a
self test involving an overall system check of the unit. If a fault is detected, the unit shuts down and displays an alarm.
2.1.4— Normal Running
The engine operates between 2700 RPM - 3600 RPM depending on the attached load. When the load increases or
decreases, the speed increases or decreases accordingly.
2.1.5— Small Load Changes
The system is designed to maintain the current engine speed for small load changes. Larger load changes result in a
change in engine speed to appropriately handle the load.
EcoGen Automatic Standby Generator Owner's Manual 5