Comparison of Typical PV Module Performances Based on the Circuit Models

IEEE PES Asia-Pacific Power and Energy Engineering Conference (APPEEC) -- OCT 07-10, 2018 -- Kota Kinabalu, MALAYSIAWOS: 000455030900038In PV systems, it is usually expected that power generation under varying conditions at any time should be maximum as much as possible. Therefore, it is essential to build a circuit model based on a widely used single or double diode model under instantly varying conditions with minimum estimation error through the measured values in the manufacturers' data sheet. It is fact that these approximate circuits models ease the performance analysis of PV systems if the unknown parameters are accurately estimated at various temperatures and unchanged irradiance levels or vice versa. This paper comparatively studies the performances of the two approximate circuit models for the four types of PV modules using the real-coded genetic algorithms. The results indicated that I-V characteristics obtained from the identified parameters exhibit almost similar trend with those given in manufacturers' data sheets under the same conditions. Besides, the estimated parameters obtained from using both models slightly show difference from each other and it can be said that the single diode model is solely satisfactory to model a typical PV model as long as they are accurately estimated.IEEE Power & Energy Soc, IEEE, Cenergi, Tenaga Nas, Tamco Switchgear Malaysia Sdn Bhd, Larsen & Toubro Grp Co, Sher Engn & Consultancy, Adv Power Solut Sdn Bhd, Ranhill, Limitless Green Energy Sdn Bhd, VELLD, MT

Modeling of a Typical Photovoltaic Module using Matlab/Simulink

2nd International Symposium on Multidisciplinary Studies and Innovative Technologies (ISMSIT) -- OCT 19-21, 2018 -- Kizilcahamam, TURKEY/0000-0002-8895-7821WOS: 000467794200118This paper presents detailed modeling principles of a typical photovoltaic (PV) module using the Matlab/Simulink software. The presented model is based on equations that are obtained from equivalent circuits of the single and double diode models. The presented models are designed with user-friendly blocks from the Simulink block library. The models provide better understanding of the output characteristics of a typical PV module and its changes, since the models can predict the behavior when it operates under various design parameters, as well as environmental conditions. The P-V and I-V output characteristics are determined using the developed models under various temperature and solar irradiation conditions. The accuracy of the developed models is validated by comparing the predicted results with the parameters provided in the datasheet of the investigated PV module.IEEE Turkey Sect, Karabuk Univ, Kutahya Dumlupinar Uni

Simian Virus 40 Large-T-Antigen-Specific Rejection of mKSA Tumor Cells in BALB/c Mice Is Critically Dependent on both Strictly Tumor-Associated, Tumor-Specific CD8(+) Cytotoxic T Lymphocytes and CD4(+) T Helper Cells

Protective immunity of BALB/c mice immunized with simian virus 40 (SV40) large T antigen (TAg) against SV40-transformed, TAg-expressing mKSA tumor cells is critically dependent on both CD8(+) and CD4(+) T lymphocytes. By depleting mice of T-cell subsets at different times before and after tumor challenge, we found that at all times, CD4(+) and CD8(+) cells both were equally important in establishing and maintaining a protective immune response. CD4(+) cells do not contribute to tumor eradication by directly lysing mKSA cells. However, CD4(+) lymphocytes provide help to CD8(+) cells to proliferate and to mature into fully active cytotoxic T lymphocytes (CTL). Depletion of CD4(+) cells by a single injection of CD4-specific monoclonal antibody at any time from directly before injection of the vaccinating antigen to up to 7 days after tumor challenge inhibited the generation of cytolytic CD8(+) lymphocytes. T helper cells in this system secrete the typical Th-1 cytokines interleukin 2 (IL-2) and gamma interferon. Because in this system TAg-specific CD8(+) cells secrete only minute amounts of IL-2, it appears that T helper cells provide these cytokines for CD8(+) T cells. Moreover, this helper effect of CD4(+) T cells in mKSA tumor rejection in BALB/c mice does not simply improve the activity of TAg-specific CD8(+) CTL but actually enables them to mature into cytolytic effector cells. Beyond this activity, the presence of T helper cells is necessary even in the late phase of tumor cell rejection in order to maintain protective immunity. However, despite the support of CD4(+) T helper cells, the tumor-specific CTL response is so weak that only at the site of tumor cell inoculation and not in the spleen or in the regional lymph nodes can TAg-specific CTL be detected

Identification of Novel HLA-A2-Restricted Human Immunodeficiency Virus Type 1-Specific Cytotoxic T-Lymphocyte Epitopes Predicted by the HLA-A2 Supertype Peptide-Binding Motif

Virus-specific cytotoxic T-lymphocyte (CTL) responses are critical in the control of human immunodeficiency virus type 1 (HIV-1) infection and will play an important part in therapeutic and prophylactic HIV-1 vaccines. The identification of virus-specific epitopes that are efficiently recognized by CTL is the first step in the development of future vaccines. Here we describe the immunological characterization of a number of novel HIV-1-specific, HLA-A2-restricted CTL epitopes that share a high degree of conservation within HIV-1 and a strong binding to different alleles of the HLA-A2 superfamily. These novel epitopes include the first reported CTL epitope in the Vpr protein. Two of the novel epitopes were immunodominant among the HLA-A2-restricted CTL responses of individuals with acute and chronic HIV-1 infection. The novel CTL epitopes identified here should be included in future vaccines designed to induce HIV-1-specific CTL responses restricted by the HLA-A2 superfamily and will be important to assess in immunogenicity studies in infected persons and in uninfected recipients of candidate HIV-1 vaccines