design & performance analysis of a smart portable pv...

International Conference on Mechanical, Industrial and Materials Engineering 2013 (ICMIME2013) 1-3 November, 2013, RUET, Rajshahi, Bangladesh.

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Paper ID: AM-08

Design & Performance Analysis of a Smart Portable PV Charger

Md. Abu Shahab Mollah1, M. A. Parvez Mahmud2, Md. Faysal Nayan1, Shahjadi Hisan Farjana3

, Sharmin Sobhan1 1Ahsanullah University of Science & Technology, Dhaka, Bangladesh

2University of Science & Technology, Daejeon, South Korea 3Khulna University of Engineering & Technology, Khulna, Bangladesh

E-mail: [email protected], [email protected], [email protected], [email protected], [email protected]

Abstract

In this paper a smart and simple PV charger for portable applications is presented. This proposed charger is low cost, low volume and light weight. Moreover this charger can realize three charging modes including the MPPT mode, the CV mode and the current limited mode. It can be integrated into an IC chip to reduce the size due to the simple structure. At last, a 60W prototype is built and tested to confirm the validity and applicability of the proposed system. Keywords: PV charger, Smart switch, Control circuit, Driver circuit.

1. Introduction

The traditional charger is the component, which transfers the power from the grid to the battery. In normal condition, the grid can supply continuing and stable energy to the battery. Therefore, the battery can be charged according to its self-condition by the traditional charger. Normally, the charging process includes two stages: in the first stage, the battery is charged in the constant-current mode. When the voltage of the battery is up to the floating voltage, the charging mode is changed to the constant-voltage (CV) mode as the second stage. During the whole charging process, only the charging current and the voltage of the battery need to be controlled. 2. PV charger

Photovoltaic or in short term PV is one of the renewable energy resources that recently has become broader in nowadays technology. PV has many benefits especially in environmental, economic and social. In general, a PV system consists of a PV array which converts sunlight to direct-current electricity, a control system which regulates battery charging and operation of the load, energy storage in the form of secondary batteries and loads or appliances. A charge controller is one of functional and reliable major components in PV systems. 3. Proposed Smart and simple PV charger

To design an efficient photovoltaic charger we use some basic part to complete the design successfully. Main part of our design consists of PV array, smart switch, and control circuit, sample and hold circuit, driver circuit. We can say our PV charger design is more smart system than other PV charger. In our design, PV array is used to reduce the system size. Step down buck converter is used as the charging circuit due to its simple structure and low cost. The overall block diagram consist of one PV array, three control loop, one smart switch, one insulation driver, one diode, one inductor, one capacitor and one lithium ion battery. So it can be smarter than other system. The block diagram of proposed smart and simple charger circuit is given in figure 1:

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actions on Energyariq, M.S. Jamil 2005, pp. 251-2

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Rincon-Mora, “Ats and Systems, Vman, “Comparisy Conversion, voAsghar, “Devel55.

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Accurate, CompVol.53, NO.11, Nson of Photovoltol. 22, NO.2, Junlopment of An A

echanical, Indus

voltage and ra

cern of environular. The off-grnergy with a hharge the batteupply is widelyrtable applicati

pact, and Power-November 2006taic Array Maximne 2007, pp. 439

Analog Maximum


atio of Voc/Vop

nmental pollutirid PV power ghigh power denery from the soly used in the daons. As a resul

Efficient Li-Ion 6,pp.1180-1184.mum Power Poin9-449. m Power Point T


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Battery Charger

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design & performance analysis of a smart portable pv...

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