Abstract
To assess the operational Status of metallized film capacitors in flexible DC transmission Systems and analyze thcir failurc causcs, a method for health assessment of metallized film capacitors using multi-frequency impedance characteristics is proposed. Firstly, an equivalent series-parallcl cquivalent modcl of the capacitor is cstablishcd to extraet characteristic Parameters representing the degradation of metallized film capacitors. Secondly, a testing platform for accclcrated aging of capacitors and a multi-frequency impedance testing platform for metallized film capacitors are set up to obtain capacitor samplcs in different degradation states due to varying degradation causcs. Finally, characteristic parameters as « aP and inflection frequency are extracted from the multi-frequency impedance curvc of metallized film capacitors to analyze the changes in characteristic parameters of different capacitors. The rcsults indicate that when capacitors deteriorate under DC voltage, if as>l. 91, it signifies an exacerbation of the conduetive part degradation, and if aP>0. 17 and thc inflection frequency is higher than 150 Hz, it indicatcs an exacerbation of the dielectric part degradation. This method not only identifies the degree of capacitor degradation but also visually reflects thc degraded parts and causes of capacitors, demonstrating good detection Performance for capacitors with poor mctallization, and inferior sealing quality.
| Translated title of the contribution | Multi-Frequency Impedance Characteristics and Deterioration State Evaluation Method of Metallized Film Capacitors |
|---|---|
| Original language | Chinese (Traditional) |
| Pages (from-to) | 160-171 |
| Number of pages | 12 |
| Journal | Hsi-An Chiao Tung Ta Hsueh/Journal of Xi'an Jiaotong University |
| Volume | 59 |
| Issue number | 3 |
| DOIs | |
| State | Published - Mar 2025 |