Deif PPU 300 - Page 43

• If the load power factor is 1, the reactive load (Q) is 0 kvar.
2. Activate switchboard control.
3. Start the generator, with no reactive load connected. Check that the generator reactive power (kvar) is zero. Record the
generator reactive power and voltage.
• The generator reactive power and voltage are shown under Live data on the display unit.
4. Connect a reactive load. Record the generator reactive power (Q, in kvar) and voltage.
5. Connect or adjust the reactive loads until the generator reactive power is 100 % of the genset nominal reactive power
(kvar). Record the generator reactive power (Q, in kvar) and voltage.
• At the very minimum, you need three measurement points, to confirm that the droop is linear. With more than two
points, you can also identify measurement errors.
6. Calculate the voltage droop using the equation below.
Droop = (Voltage
low load
- Voltage
high load
) / (Q
high load
- Q
low load
) × Q
nominal
/ Voltage
nominal
× 100
Example of voltage droop
A genset runs at a nominal voltage of 220 V, and has a nominal reactive power (Q) of 1000 kvar. The following
measurements are taken:
# Reactive power (Q) [kvar] Voltage [V]
1 0 220.0
2 223 218.0
3 674 214.1
4 985 211.3
PPU 300 Commissioning guidelines 4189341106 UK
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