In certain power networks, a significant difference may exist between the rated voltage and the service voltage. For example, a capacitor rated at 400 V may be used in a 380 V system. In such cases, the actual reactive power output of the capacitor varies with voltage and frequency. This tool calculates the real reactive power delivered by a capacitor under non-rated conditions.
| Parameter | Description |
|---|---|
| Input Voltage | Actual operating voltage of the network (e.g., 380V, 400V), unit: Volts (V) |
| Supply Frequency | Operating frequency of the network (e.g., 50 Hz or 60 Hz), unit: Hertz (Hz) |
| Capacitor Rated Power | Nominal reactive power rating of the capacitor, unit: kVAR |
| Capacitor Rated Voltage | Rated voltage specified on the capacitor nameplate, unit: Volts (V) |
| Capacitor Rated Frequency | Design frequency of the capacitor, typically 50 Hz or 60 Hz |
The reactive power output of a capacitor is proportional to the square of the applied voltage:
Where:
- Q_actual: Actual reactive power output (kVAR)
- Q_rated: Rated reactive power of the capacitor (kVAR)
- U_in: Input voltage (V)
- U_rated: Rated voltage of the capacitor (V)
- f_supply: Supply frequency (Hz)
- f_rated: Rated frequency of the capacitor (Hz)
A 10% increase in voltage results in approximately 21% higher reactive power (due to quadratic relationship)
Overvoltage can cause overheating, insulation breakdown, or reduced lifespan