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Capacitors are important passive electrical components. For this reason, the aim is to maximize the quality of these products and their resistance to environmental influence. Some of the main problems with capacitors are: the dependence of their capacitance on the charging voltage and the ambient temperature. The capacitance usually depends on the voltage and almost always decreases while increasing charging voltage. In addition, the capacitance of this type of capacitor is strongly dependant on temperature, charging time, current and frequency. Therefore, they are not recommended for use in circuits where linearity is required (sound equipment, measuring devices). Additionally, reduction in capacity at high voltages must also be taken into account regarding power circuits. The aim is to produce capacitors whose capacitance and temperature dependence would be minimal or at least the alterations in capacitance dependence on voltage would be inverse - the capacitance would increase with increasing voltage. This article introduces the research of a ceramic capacitor with a TDK manufactured dielectric perovskite strip. The aim of the research is to find out the behaviour of this capacitor using reverse voltage, to investigate the dependence of the capacitance of a ceramic capacitor on voltage and current and the dependence of the capacitance on temperature. Furthermore, evaluation of the aging properties of these capacitors is done. Firstly, a capacitance measurement model was constructed, which works in a wide range of voltages from 0 to 500 V and ensures a constant charge / discharge current of the capacitor. The suitability of this model for use in further testing was tested using a stapling capacitor. The capacitive dependencies of the test capacitor on the voltage and temperature, which correspond to the properties specified by the manufacturer, were measured. Capacitance-voltage dependency studies were carried out using three different discharge currents. Examination of the connection with opposite polarity showed that the capacitor irreversibly loses its capacitance due to the inverse voltage. Monitoring of the self-discharge rate showed that a voltage of opposite polarity connected to a capacitor with a perovskite dielectric permanently reduces the capacitance of this capacitor. In addition, such a violation significantly increases its leakage current, which is particularly strong at voltages |
