MV POWER CAPACITORS

Construction

MV power capacitors are manufactured with all-film technology. The dielectric is polypropylene foil impregnated with synthetic liquid known under the trade name JARYLEC, which is harmless to health and environmentally friendly. Electrodes are made of aluminum foil. This construction ensures extremely low losses of capacitors.

Internal interconnection is in the case of three-phase units to the star and is marked with "Y", for single-phase it is "I". The units have built-in internal discharge resistors reducing the voltage to 75 V within 10 minutes. The three-phase and single-phase units are in fully insulated containers.

Internal fuses

The function of internal fuses is isolating a faulty element from the others to allow further function of the capacitor unit. For further capacitor function it's necessary to take into account capacitance change of the capacitor. The internal fuses in capacitor are restricted with the energy contained in the each internal section.

This energy is very important for secure disconnection of the fuse in the case of fault inside any element. For their proper function there is important that capacitor has sufficient energy for save disconnection of the fuse. On the other hand the fuses must not disconnect during switching (on and off) of the unit. Both types of capacitors (internally fused or not) would be equipped with correctly selected external fuses.