Distinct degradation processes in ZnO varistors: reliability analysis and   modeling with accelerated AC tests

Hadi YADAVARI; Mustafa ALTUN

Article Details

Distinct degradation processes in ZnO varistors: reliability analysis and modeling with accelerated AC tests

Authors:

Hadi YADAVARI | Mustafa ALTUN

Publisher:

TUBITAK

Journal:

Turkish Journal of Electrical Engineering and Computer Science 2017 Vol.25 Issue 4, pp.3240-3252

Document Type:

Article

Publication Date:

7/2017

Document Language:

Turkish

Document ID (Org No.):

2000736232

Frequency:

Bimonthly

eISSN:

1303-6203

pISSN:

1300-0632

Abstract:

 

In this study, we investigate different degradation   mechanisms of zinc oxide (ZnO) varistors. We propose a model that shows how   Vv (defined as DC varistor voltage when a 1-mA DC current is applied)   changes with time for different stress levels. For this purpose, accelerated   degradation tests are applied for different AC current levels and voltage   values are then measured. Different from the common practice in the   literature that considers degradation with only decreasing Vv values, we   demonstrate either an increasing or a decreasing trend in the Vv parameter.   The tests show a decreasing trend in Vv for current levels above a certain   threshold and an increasing trend for current levels below this threshold.   Considering both of these degradation mechanisms, we present a mathematical   degradation model. The proposed model exploits the physics of the   degradations for a single-grain boundary that is the core structure of a ZnO   varistor. To validate the proposed model, we perform Monte Carlo simulations   and the results are compared with those obtained from accelerated AC tests.   As a summary of this study, we introduce a conceptual accelerated AC test   methodology to analyze the reliability of the new ZnO varistor.

Article Details

Distinct degradation processes in ZnO varistors: reliability analysis and modeling with accelerated AC tests

Authors: Hadi YADAVARI | Mustafa ALTUN

Publisher: TUBITAK

Journal: Turkish Journal of Electrical Engineering and Computer Science 2017 Vol.25 Issue 4, pp.3240-3252

Document Type: Article

Publication Date: 7/2017

Document Language: Turkish

Document ID (Org No.): 2000736232

Frequency: Bimonthly

eISSN: 1303-6203

pISSN: 1300-0632

Issues

Authors:

Hadi YADAVARI | Mustafa ALTUN

Publisher:

TUBITAK

Journal:

Turkish Journal of Electrical Engineering and Computer Science 2017 Vol.25 Issue 4, pp.3240-3252

Document Type:

Article

Publication Date:

7/2017

Document Language:

Turkish

Document ID (Org No.):

2000736232

Frequency:

Bimonthly

eISSN:

1303-6203

pISSN:

1300-0632