The characteristics of a two-layer structure on the basis layers varistor ceramics and polymeric PPTC nanocomposite being in thermal contact for purpose using it as limiter constant voltage long-term varying electrical overvoltages are analyzed. A theoretical model such has been developed, its main simulated. It is shown that provision required output limitation performed by selecting classification layer. maximum current layer heating determined intensity heat transfer to environment....

For quantitative estimation of the degree electrical disorder (electrical inhomogeneity) in ZnO varistor ceramics caused by a variation barrier height at different grain boundaries sample, comparison threshold electric fields (onsets highly nonlinear current–voltage characteristics) and single boundary (GB) is suggested approved. At dc degradation similar behavior characteristics GB observed. The percolation model Shklovskii–De Gennes applicable for description ceramics. not dependent on...

The problems of reducing the cost ensuring safe operation solar cells by using low-cost elements solid-state electronics to protect against overvoltage photovoltaic arrays are considered. results experimental studies use a varistor-posistor structure based on metal oxide varistor and PPTC fuses PolySwitch type being in thermal contact prevent overvoltages series connections presented. General schemes for considered limit indicated constant given justified. requirements parameters this...

Purpose The purpose of this paper is to minimize and prevent current overloads (including the elimination abnormal fire hazardous situations) in photovoltaic solar arrays by using low-cost functional electronic elements, particular, new PolySwitch PPTC fuses. Design/methodology/approach modeling method has been used investigate circuit solution use type fuses arrays. Findings It shown that limitation short-circuit with parallel connection components (photovoltaic cells or their modules) can...

The manifestation and formation of various defects in the process exploitation real photovoltaic cells their compounds as well work regime changing non-uniform illumination lead to so-called series parallel inconsistencies (differences electrical characteristics) between separate groups. This results local overheating intensifying degradation processes. In some cases temporary disconnection (isolation) corresponding elements solar batteries is more appropriate order increase service life....

The results of experimental study the transformation light current-voltage and volt-watt characteristics for parallel connections photovoltaic modules when using “PolySwitch” polymer resettable fuses are given. conditions selecting such which allow their correctly triggering minimize current overload formulated experimentally verified. It is established that if connected in series to circuits all modules, thus forming a unit, this prevents situation as complete loss electrical energy...

The electromigration degradation model of nonlinear electrical properties non‐uniform structures with intercrystallite potential barriers is developed. It allows connecting the increasing near surfaces concentration volume donors by their migration in field at heating up means current process degradation. results experimentally observed deterioration varistoral properties, and asymmetrical deformation currentvoltage characteristics during exploitation.

One of the main problems in ensuring reliability solar electrical power sources is local overheating, when hot spots form photovoltaic cells arrays. It currently considered that these negative phenomena are caused, among other things, by overvoltage circuits This leads to appearance defective elements and a significant decrease functionality entire generation system up its complete failure. study considers possible ways increase arrays using thermistor thermocontacting layers for preventing...

Recently, the combined two-layer structure based on varistor ceramics and polymer posistor nanocomposites with carbon filler (known as PolySwitch resettable fuses) has been seen one of promising elements for protecting electrical circuits from long-term overvoltages. The layers are in thermal contact. main functional property such a is sharp increase (by several orders magnitude) resistance nanocomposite layer during transfer energy heated by overvoltage. Detailed information about behavior...

Purpose The purpose of this paper is to develop the models dielectric permittivity dispersion heterogeneous systems based on semiconductors a level that would allow apply effectively method broadband spectroscopy for study electronic processes in ceramic and composite materials. Design/methodology/approach new approach determining complex with semiconductor particles used. It includes finding analytical expression effective separate particle spherical shape. This takes into account...

Recently, much attention has been paid to the study of influence current overloads and local overheating on degradation electrical characteristics photovoltaic components solar arrays. First all, it is connected with tasks increasing reliability durability operation such renewable sources energy. Such studies are particular interest due recent emergence new methods devices for improving arrays by isolating inactive (defective or shaded) areas their (photovoltaic cells modules). This paper...

Purpose – The purpose of this paper is to develop a generalized model the nonlinear conductivity varistor ceramic suitable for solving problems prediction and control nonlinearity, stability properties. Design/methodology/approach modeling current-voltage characteristic intergranular barrier in metal oxide ceramics based on development algorithm. It includes all known mechanisms electrotransfer wide range voltages currents characteristics, also takes into account deviation form Schottky...

The article discusses the relevance of developing a laboratory model for experimental study operating parameters installations with batteries, voltage inverters, and photovoltaic solar converters. Materials research methods are described, including use modern technologies such as microcontrollers WiFi, analog-to-digital converters, cloud environments data storage analysis. results studies presented, which demonstrate that correct setting can significantly reduce load on batteries increasing...

The ability of a structure in the form photovoltaic element with built-in posistor layer based on polymer nanocomposite carbon filler being direct thermal contact to protect against overvoltages was studied experimentally and by simulation. It shown that current voltage reverse-biased [Formula: see text]–[Formula: text] junction are limited decrease from moment when temperature this reaches values close tripping low-conductivity state. has value layer, which is equal text]C. possibility...

A model and a calculation scheme that allow describing investigating temperature voltage drop distributions in solar photovoltaic cell plates the presence of an overvoltage displacing p-n junction reverse direction are developed. It is found for photocell distribution stabilizes within several seconds after onset. In this case, maximum size region local heating (called “hot spot”) set. An increase value leads to spot” size. For cells with lower electrical resistances, takes place at...

Purpose – The purpose of this paper is modeling the effect negative capacitance in capacitance-voltage characteristic intergranular potential barrier varistor structure. Design/methodology/approach metal oxide ceramics based on development algorithm. It includes all known mechanisms electrotransfer a wide range voltages and currents, also takes into account voltage drop interlayer barrier. Findings models algorithms for calculating characteristics single with use most established...

Recently, solar panels have become one of the most desirable sources renewable electrical energy, and thus requirements for their reliability, in particular to maintain basic functional properties at elevated temperatures, are increasing. The element batteries is photovoltaic converter. Until now, degree degradation ways protect converters during overheating corresponding real situations exploitation, not sufficiently studied. In this paper, authors study important problems arising...

Electrical characteristics of experimental two-layer structure based on layers varistor ceramics and polymer nanocomposite with carbon filler being in thermal contact are studied. A layer such is used PPTC fuses the PolySwitch technology. The dependences output voltage layer, current temperature input applied to entire analyzed. It shown that an increase voltage, reaches a certain value does not change after that. concluded ceramics–PPTC type can be as limiter constant electrical for...