Hi,

How is the capacitor bank connected? Is the capacitor bank at distribution level or in an industrial plant? There might be certain causes for the explosion which includes:
a. Transient Overvoltage
b. Capacitor Energization/Switching
c. Harmonics

The first item might be experienced when there is a ground fault located within the capacitor bank installation. The second one is when the inrush current is very large that it exceeds the rate of inrush rating of the capacitor bank. The last item is experienced when the capacitor bank is not sized properly i.e. no impedance/frequency scan conducted.

Let me know your insights here. Thanks.

Regards,