New MPPT solar generation implemented with constant-voltage constant-current DC/DC converter

摘要

To obtain the maximum power from solar PVs, various maximum power point tracking (MPPT) methods have been developed. Most of these methods use various Perturb and Observe (P&O) algorithms to track the MPP of the solar array. However, a typical solar generation system consists of a solar array and a DC/DC converter. Making the output of the solar array maximum does not certainly result in the maximum DC/DC converter output. Therefore, it is suggested [1] that the PV array and the DC/DC converter should be considered as one system to maximize the overall system output. This paper reported an implementation of the new MPPT method which uses a constant-voltage constant-current (CVCC) DC/DC converter. It analysed the three working states of a CVCC DC/DC controller and developed a MPPT searching algorithm based on this kind of converter. With the CVCC characteristics of the DC/DC converter, the new method largely simplified the MPPT searching process. The experiment results and the comparison with the benchmark MPPT solar charger which is commercially available verified the effectiveness of the new method.