Vacuum circuit breaker´s electrical life for shunt capacitor switching

In order to improve the efficiency of power distribution and for economic reasons, the power factor is corrected on medium voltage electrical network. To do this, it is mandatory to switch once or twice a day a capacitor bank. Vacuum circuit breakers are frequently used to switch capacitor banks. An automated system is used to evaluate the electrical life of vacuum circuit breakers depending on the shunt capacitor switching parameters. Tests consist of opening and closing operations on a three-phase circuit breaker. This system has two main advantages; the maximum reactive power available is 20 Mvar at 24 kV with inrush currents up to 22 kA (common values in customer applications are under 10 kA) and the short endurance test duration is only 8 days for 10,000 operations compared to 5 weeks in laboratories.