An Optimal Control Strategy for DC Bus Voltage Regulation in Photovoltaic System with Battery Energy Storage

<table>Comparison of the battery module discharge curves at different current magnitudes: (a) simulated Yuasa NP4-12 discharge curve and (b) manufacturer data of the Yuasa NP series battery (note that battery module’s capacity <svg height="17.9625" id="M188" style="vertical-align:-3.22281pt" version="1.1" viewbox="0 0 96.887497 17.9625" width="96.887497" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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<g transform="matrix(.012,-0,0,-.012,53.888,17.763)"><path d="M152 404l81 35q23 10 41 10q81 0 139 -61.5t58 -149.5q0 -107 -74.5 -178.5t-176.5 -71.5q-71 0 -147 36v555q0 48 -9.5 59.5t-56.5 15.5v23q79 10 145 35v-308zM152 374v-258q0 -20 6 -35q7 -19 30 -37t58 -18q63 0 99.5 50t36.5 137q0 82 -43.5 131t-108.5 49
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<g transform="matrix(.017,-0,0,-.017,73.962,13.688)"><path d="M535 323h-483v50h483v-50zM535 138h-483v50h483v-50z" id="x3D"></path></g><g transform="matrix(.017,-0,0,-.017,88.666,13.688)"><path d="M456 178h-96v-72q0 -51 12.5 -62.5t72.5 -16.5v-27h-256v27q65 5 78 17t13 62v72h-260v28q182 271 300 426h40v-407h96v-47zM280 225v295h-2q-107 -148 -196 -295h198z" id="x34"></path></g>
</svg> Ah). Note. <svg height="11.75" id="M189" style="vertical-align:-0.15048pt" version="1.1" viewbox="0 0 12.1125 11.75" width="12.1125" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
<g transform="matrix(.017,-0,0,-.017,.062,11.4)"><path d="M682 629q-1 -16 -1.5 -72t-2.5 -86l-31 -4q-5 92 -51 129t-139 37q-100 0 -177 -49t-116 -125t-39 -162q0 -122 66 -201t182 -79q83 0 137 42.5t112 128.5l26 -15q-12 -31 -42.5 -88t-45.5 -75q-139 -27 -199 -27q-148 0 -243 81.5t-95 226.5q0 173 129.5 274.5
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</svg>: given capacity as stated on each battery in Ah.</table>

The Scientific World Journal

fig8

Figure 8

Figure 8: An Optimal Control Strategy for DC Bus Voltage Regulation in Photovoltaic System with Battery Energy Storage 