SEPIC And PV Market

1216 Words3 Pages

1 INTRODUCTION: The world’s Renewable sources growing up recently and photovoltaic (PV) market will grow up to 30 GW by 2014, due to the following policy-driven scenario [1]; the role of grid-connected PV systems in distribution energy systems will become important, and the PV inverter will also play a unique role in this growing market. To obtain higher dc-link a String-type inverters use series connections with numerous modules to the main electricity through a dc-ac inverter [2], [4]. The single-ended primary inductance converter (SEPIC) having non- inverting output voltage [15][16]. Although the boost converter usually has higher efficiency than the SEPIC, nonetheless, it is only applicable for cases where the battery voltage is higher than the PV module voltage. The SEPIC’s buck boost features extends the applicable PV voltage and thus increases the adopted PV module flexibility. The comparison of various buck–b4250 boost converters from voltage gain and efficiency and cost. It is shown in Table.1 Among these converters, although the SEPIC is not the best from the views of efficiency and cost, it still has the merits of no inverting polarity, user free-to-drive switch, and low input-current pulsating for high-precise MPPT that makes its integral characteristics suitable for the low-power PV charger system. This paper will investigate the SEPIC with the PV module input and zeta converter with PV module input. Switched z source inverter interface with SEPIC and Zeta converters. Zeta converter provides either a step-up or a step-down function to the output, in a manner similar to that of the buck-boost or SEPIC converter topologies. The conventional Zeta converter is configured of two inductors, a series capacitor and a diode. ... ... middle of paper ... ...ing N1 and secondary winding N2. To simplify the circuit analysis of the proposed converter, the following assumptions are made. 1) All components are important, except for the leakage inductance of coupled inductor T1.The ON-state resistance RDS(ON) and all parasitic capacitances of the main switch S1 are neglected, as are the forward voltage drops of the diodes D1 ∼ D3. 2) The capacitors C1 ∼ C3 are sufficiently large that the voltages across them are considered to be constant.3) The ESR of capacitors C1 ∼ C3 and the parasitic resistance of coupled-inductor T1 are neglected. 4) The turn’s ratio n of the coupled inductor T1 winding is equal to N2/N1. The operating principles for continuous-conduction mode(CCM) are now presented in detail. The typical waveform of several major components during one switching period. The five operating modes are described as follows.

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