Abstract: A method and device for predicting defects of a capacitor, the method including determining the ripple voltage (Udc), the temperature (TP), and the current (Ic) of the capacitor, determining the value of an equivalent series resistance (ESR) of the capacitor, and the capacitance value (C) of the capacitor using a digital filter, determining information representative of the state of aging of the capacitor according to the temperature of the capacitor, and displaying that information and information representative of the value of the capacitance (C) and/or information representative of a cause associated with the state of aging according to the capacitance value. The device may include a converter and an uninterruptible power supply.

Abstract: A method for predicting defects of at least one capacitor comprising: determining the ripple voltage, the temperature, and the current of the capacitor, determining the value of an equivalent series resistance of the capacitor and the capacitance value of the capacitor by means of a digital filter, determining an item of information representative of the state of ageing of the capacitor according to the temperature of the capacitor, and displaying said information and information representative of the value of the capacitance or/and information representative of at least one cause associated with the state of ageing according to the capacitance value. A device for predicting defects of at least one capacitor to implement the method. A converter and uninterruptible power supply comprising the device.

Abstract: The medium voltage static switch is formed by serial connection of power semi-conductors, preferably of MOS type, controlled by a capacitive line. A diode is connected in parallel with the capacitor of the capacitive line between the gates of two adjacent semi-conductors. The control voltage is applied to a single control input, between the gate and source of the first stage semi-conductor.