Device Modelling on Solar Cells

The research team of the Laboratory headed by Prof. Valery Rumyantsev is carrying out the following investigations and developments in frames of the Megagrant for research “Development of new generation photovoltaics on the base of materials with the intermediate band”:

  • creation of specialized equipment for investigating photoresponce spectra and I-V characteristics at illumination in a wide range of temperatures including super-low ones, which ensures sunlight concentration ratios of not less than 1000;
  • development of sunlight optical concentrators and concentrator modules corresponding to large extent to conditions of for optimum radiation conversion in PV cells based on materials with the intermediate band;
  • performance of indoor and outdoor investigations of sunlight conversion processes in nanoheterostructures with an active region performed of materials with the intermediate band;
  • development of ways for optimizing conditions for delivering optical power and removing residual heat from PV cells to ensure the maximum sunlight conversion efficiency.

We are solving a wide range of tasks associated with developing photovoltaic (PV) conversion facilities using PV cells based on AIIIBV compounds. The tasks can be formulated as follows:


  • performance of investigations of PV parameters of single-junction photovoltaic converters (PVCs) of laser radiation and of multijunction (MJ) PVCs of the concentrated sunlight (I-V characteristics in a wide range of photo-current densities and temperatures, components of the intrinsic resistance and others);

  • projection and fabrication of the initial and secondary sunlight concentrators and study of their properties;

  • development of solar concentrator PV module designs for terrestrial and space applications and indoor investigation of their properties;

  • creation of procedures and performance of outdoor investigations of characteristics of concentrator modules for terrestrial application including those at long-term operation;

  • elaboration and fabrication of sunlight tracker system prototypes;

  • development and manufacture of prototypes of solar power installations with concentrator PV modules;

  • elaboration and manufacture of measuring equipment for carrying out the enumerated above researches including that for supplying that to the scientific enterprises in Russia and abroad.



The following procedures for investigations with applying the manufactured computerized equipment are used:


  • measurement of the PV conversion efficiency in a pulsed mode of illumination at sunlight concentration ratios of up to 1000 in conditions of varying spectral composition;

  • measurement of concentrated and distributed components of the PV cell intrinsic resistance;

  • measurement of the radiation concentrator optical efficiency;

  • measurement of the operating temperature of a p-n junction of PV converters of laser and solar radiation at different modes of power transfer to a load;

  • determination of the efficiency of the luminescent radiation transfer in MJ PV cells.



For concentrator modules of terrestrial and space application, we have developed Fresnel lens panels being fabricated by the “silicone-on-glass” technology. In the “terrestrial” version, the panels consist of 288 4x4cm² or 128 6x6cm² lenses. The receiving panel of PV cells in the modules is made on a glass basement by the unique technology for concentrator modules – sealing of PV cells with using laminating films. The elaborated design of modules (so called SMALFOC modules, see corresponding publication) ensures the minimum cost of their production owing to the use of optimally selected cheap construction materials and to a possibility to optimize the fabrication process.

A long-standing experience in designing sun-trackers and solar power installations with concentrator modules has been realized in a series of facilities ensuring automated operation of modules in any latitudes at elevated resistance to wind loads by locating them in a form of steps.


Among the created measuring equipment, a line of pulsed sunlight simulators based on xenon lamps and automated complexes for recording PV cell´ I-V characteristics should be noted. The given set of measuring devises ensures a possibility for sorting PV cells on epitaxial plates before mounting them on heat-sinks, for measuring main PV characteristics after their mounting, for measuring the efficiency of assembled concentrator modules in illuminating by collimated light flux reproducing intensity, spectral composition and divergence of direct sunlight rays. Also developed, fabricated and supplied to corresponding Russian enterprises is a set of solar simulators for controlling parameters of large-sized (2x3m²) solar arrays of MJ PV cells for space application.

1.png Fig.1. A family of the illuminated I-V curves for a 3-junction cell at high sun concentration ratios (designated illumination cell area is 2.3 mm in diameter).
2.png Fig.2. Wafer map with a black/white cell classification. Each circle represents one solar cell. The brighter the area, the higher is a photoinduced EL-signal from the top InGaP sub-cell and the higher is expected voltage at maximum power point in working regime.
3.png Fig.3. Optical scheme of a SMALFOC module fragment.
4.png Fig.4. Assembled concentrator module of the SMALFOC design: view from the side of the lens panel and view from the side of the laminated photo-receiver panel with a standard junction box. Dimensions of the 128 lenses panel and photo-receiver panel are 480x960 mm²; the module output voltage is 48 V (16 connected in series sub-modules with SCs). In the module version with 288 lenses output voltage is 36 V for the same external dimensions.
5.png Fig. 5. Picture of one of the experimental solar power installations of the Ioffe Institute with concentrator modules of 1 kW total power.
6.png Fig. 6. Picture of the flash solar simulator and measurements system for characterization of the larger-area solar arrays for space applications.

Elder publication similar to current project:

Progress In Developing HCPV Modules Of SMALFOC-Design
Proc. of the 9th Int. Conf. on Concentrating Photovoltaics, 15-17 April 2013, Miyazaki, Japan, pp. 185-188 
V.D.Rumyantsev, V.M.Andreev, A.V.Chekalin, N.Yu.Davidyuk, O.A.Im, E.V.Khazova, N.A. Sadchikov

Cell Chip Temperature Measurements In Different Operation Regimes Of HCPV Modules
Proc. of the 9th Int. Conf. on Concentrating Photovoltaics, 15-17 April 2013, Miyazaki, Japan, pp. 138-141
V.D.Rumyantsev, A.V.Chekalin, N.Yu.Davidyuk, D.A.Malevskiy, P.V.Pokrovskiy, N.A.Sadchikov, A.N.Pan'chak

Fabrication and study of p-n structures with crystalline inclusions in the space-charge region
2013, Semiconductors, v.47, 12, pp.1652-1655
V.S.Kalinovsky, R.V.Levin, B.V.Pushniy, M.N.Mizerov, V.D.Rumyantsev, V.M.Andreev

Evaluation of the Solar Cell Internal Resistance in I-V Measurements under Flash Illumination
Proceedings of the 8th International Conference on Concentrating Photovoltaics (CPV-8), April 16-18, 2012, Toledo, Spain, pp. 152-156
V.D.Rumyantsev, V.R.Larionov, D.A.Malevskiy, P.V.Pokrovskiy, A.V.Chekalin, M.Z.Shvarts

Multijunctional flash solar simulator: 3 in 1
Proceedings of the 27th European Photovoltaic Solar Energy Conference and Exhibition, 24-28 September 2012, Frankfurt, Germany, pp. 214-217
V.D.Rumyantsev, V.R.Larionov, D.A.Malevskiy, P.V.Pokrovskiy, A.N.Panchak

HCPV modules with combined lens/guide secondaries
Proceedings of the 27th European Photovoltaic Solar Energy Conference and Exhibition, 24-28 September 2012, Frankfurt, Germany, pp. 236-238
V.D.Rumyantsev, V.M.Andreev, A.V.Chekalin, N.Yu.Davidyuk, E.A.Ionova, D.A.Malevskiy

Solar Simulator For Characterization Of The Large-Area HCPV Modules
Proceedings of the 7th International Conference on Concentrating Photovoltaics (CPV-7), April 4-6, 2011, Las Vegas, USA, pp. 212-215
V.D.Rumyantsev, V.R.Larionov, D.A.Malevskiy, P.V.Pokrovskiy,N.A.Sadchikov

Solar concentrator modules with silicone-on-glass Fresnel lens panels and multijunction cells
Optics Express, Vol. 18, Issue S1, pp. A17-A24, 2010 , 

Transfer of power by photons in HCPV triple-junction cells
Proceedings of the 6th International Conference on Concentrating Photovoltaic Systems, 6-11 April 2010, Freiburg, Germany, pp. 20-23
V.D.Rumyantsev, N.I. Kozhuchov, D.A.Malevskiy, P.V.Pokrovskiy

Head of the research group: Prof. Valery Rumyantsev
Phone: +7-812-292-73-94