Design and Implementation of 1.2KW PV Power Supply for Battery charging and discharging system

• Main Authors: Chien Wei Lu, 呂健瑋
• Other Authors: S. Y. Tseng
• Format: Others
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/61966130759062368181

碩士 === 長庚大學 === 電機工程學系 === 100 === The main objective of this thesis to design and implement a battery charger and discharger for photovoltaic (PV) power system. In the proposed charger, since output power of PV arrays depends on the insolation variation of sun, the controller with DSP is adopted to implement maximum power point tracking (MPPT) of PV arrays and CC-CV hybrid charge of battery. The proposed discharger, also uses the DSP controller to achieve battery discharge with constant current (CC) method. Moreover, the DSP one is used to detect battery voltage for avoiding undercharge and overcharge of battery to expand its life cycle. The proposed charger system adopts interleaved boots converter associated with boost type snubber to increase conversion efficiency. In order to simplify circuit structure of the proposed one, two boost type snubbers can use switch integration technique to merge them. The proposed converter can be operated with zero-voltage switching at turn on and with zero-voltage transition at turn off. Moreover, the proposed snubber can be used in N sets of interleaved boost converters to increase conversion efficiency. The discharger adopts an interleaved boost converter with coupling-inductor circuit to achieve high step-up voltage ratio. Finally, from experimental results it can be found that, the proposed charger can achieve MPPT and CC-CV charge feature and the proposed discharger can implement constant current(CC) discharge for verifying the feasibility of the proposed PV power system.