Capacitor current calculation

Capacitor current calculation
According to the nameplate of an imported brand, reference example: to achieve 50 Kvar reactive power output. The capacitor needs to be configured as a 70 Kvar capacitor. Its rated current is: 81.6A, the rated voltage is: 500V, product model: 7R50 + XD 70.
Calculate according to the formula:
Rated current I=Q (1.732 U)=70÷(1.732X0.5) =80.8381A
And according to I=U / Z=U (1 / wc) = wcU
So the wc=I/U=81÷0.5=162
1. When the capacitor is running at the system voltage of 480V: I=wc U Q=1.732U I
Current (A) I=162X0.48=77.76A 78A
Capacity (Kvar) Q=1.732U I=1.732X0.48X77.76=64.665
2. When the capacitor is operating at the 450V system voltage:
Current (A) is I=162X0.45=72.9A 73A
Capacity (Kvar) Q=1.732U I=1.732X0.44X72.9=56.857
3. When the capacitor is operating at 440V system voltage:
Current (A) I=162X0.44=71.28
Capacity (Kvar) Q=1.732U I=1.732X0.44X71.28=54.354
4. When the capacitor is operating at the 420V system voltage:
Current (A) I=162X0.42=68.04A 68A
Capacity (Kvar) Q=1.732U I=1.732X0.42X68.04=49.4950
In summary, the calculation formula shows that the lower the system voltage, the operating current is smaller, and the actual output capacity is smaller. Considering that the general low-voltage distribution system operating voltage is 380V ± 5%.
Take its upper limit for calculation. U=380 + (380X0.05) =399400V. Take the capacitor end voltage by about 28V. The actual operating voltage is assumed to be 430V.
Current (A) is I=162X0.43=69.66A 70A
Capacity (Kvar) Q=1.732U I=1.732X0.43X69.66=51.852
If the actual current is 380V, the voltage at the capacitor end is raised about 28V after considering the addition of a 7% reactor. Actual operating voltage is assumed to be 410V.
Current (A) I=162X0.41=66.4267A
Capacity (Kvar) Q=1.732U I=1.732X0.41X66.42=47.1648
The following figure is the nameplate of an imported capacitor: