В статье приводятся результаты экспериментальных и теоретических исследований процессов самовосстановления металлопленочных конденсаторов в форсированных режимах. Предложена методика испытаний конденсаторов, позволяющая регистрировать акты самовосстановления в широких диапазонах напряжений и времен. Показана возможность сохранения работоспособности металлопленочных конденсаторов в условиях многократного (4 - 6 раз) форсирования электрической нагрузки. Предложен механизм деградации конденсаторов, обусловленный развитием множественности процессов самовосстановления, приводящий к постепенному накоплению высокопроводящих зон вблизи каналов пробоя. Создана модель единичного процесса самовосстановления, позволяющая оценивать энергию самовосстановления для разных уровней прикладываемого напряжения. В качестве параметра для оценки скорости деградации и прогнозирования ресурса металлопленочных конденсаторов в форсированном режиме предложено использовать величину суммарной энергии самовосстановления

Articolul prezintă rezultatele investigaţiilor experimentale şi teoretice ale proceselor de auto-vindecare în condensatoarele cu pelicule metalizate în regimuri forţate. Se propune o metodă de testare a condensatoarelor, care permite să se înregistreze actele de auto-vindecare într-o gamă largă de tensiuni şi timp. Se demonstrează posibilitatea de asigurare a robusteţei condensatoarelor cu electrozi metalizaţi şi dielectric din pelicule de mase plastice în condiţii de multiple depăşiri a sarcinii admisibile (de 4-6 ori) în caz de forţare a sarcinii electrice. S-a propus mecanismul de degradare al condensatoarelor, ca urmare a derulărării a mai multor procese de auto-vindecare, ceea ce duce la acumularea treptată a zonelor cu conductivitate ridicată lângă canale de degradare. S-a propus un model al procesului caracteristic uni act de auto-vindecare, care vă permite să se evalueze puterea de auto-vindecare pentru diferite nivele de tensiune aplicate. Ca parametru pentru a estima rata de degradare si prognozare a duratei de viaţă a condensatoarelor cu auto-vindecare cu dielectric din peliculă metalizată în regim forţat de sarcină se propune să se utilizeze energia totală a proceselor de auto-vindecare

The advantage of modern metallized film capacitors is high reliability caused by so-called ability to self-healing. Application of such capacitors in overload modes (at short lifetimes) can significantly improve their technical and volumetric characteristics. In spite of the fact that self-healing had been investigated over the last decades, the existing theoretical notions and the reported experimental results did not led to the commonly accepted model of the process of self-healing. Moreover, there is no information on film capacitors performance in overload modes in the literature. In this paper, we present the results of experimental and theoretical study on processes of self-healing of film capacitors in overload modes. The capacitors’ testing method is proposed. The method allows to record events of self-healing over a wide range of voltages and times. It is shown that capacitors are able to operate at voltages 4-6 times higher than nominal value. The capacitors’ degradation mechanism is caused by multiple self-healing events that lead to the gradual accumulation of highly conducting zones near the breakdown channels. Model of single event of self-healing is developed. This allows estimating the energy of self-healing for different levels of applied voltage. It is suggested to use the value of cumulative energy of self-healing as a parameter for estimating the rate of degradation and predicting the film capacitor’s lifetime