Application of power compensating concept for high efficiency maximum power point tracking in grid-connected photovoltaic system

High efficiency is one of the most important requirements for grid-connected photovoltaic (PV) systems. Power compensating concept promises high efficiency maximum power point (MPP) tracking and hence improves the efficiency of the whole PV systems. In this paper, the compensating concept in grid-connected PV systems with kinds of power architectures was summarized. It was found that even with the compensating concept, the efficiency requirement of the converter dedicated for the realization of the compensating concept, which was defined as the photovoltaic regulator (PVR), never relaxed. However, obvious efficiency advancement comes true when high efficiency topology, such as phase-shifted-full-bridge (PSFB), is adopted as the PVR. A 98% high efficiency MPP tracking was achieved for a 240 W PV panel by using the compensating concept where a 200 kHz operated PSFB was adopted as the 85 W PVR.