Question 2
a. A PV module with below IV characteristics is used to charge a48 V[8 mar battery with internal resistance0.1Ω. Assume the PV module is directly connected to the battery and the battery is in charging state. Determine the approximated charging current and the power delivered to the battery. b. Calculated the module rated (MPP) power and fill factor (FF). Discuss whether the above charging system is efficient? [4 mar Page 3 of 5 c. Design a dc/dc converter to put between the PV module and battery to allow the PV module operates at MPP. You need to determine the type of the dc/dc converter (buck or boost), it's step ratio and the inductor size to operate in CCM. Assume the switching frequency isfs=20kHz. What is the battery's charging current if PV operates at MPP in this system? Draw the block diagram of the system. d. The PV module is composed of 90 cells in series, and each cell has a parallel resistance of5Ω. Ignore the series resistance. If only the top PV cell is shaded, calculate the module MPP voltage and power for two cases; i) without bypass diode,[8mar ii) with bypass diode with on-state voltage of0.7 V. Note there are 3 bypass diodes for the module, each across 30 cells.