Photovoltaic (PV) system is one of the promising renewable energy technologies. Although the energy conversion efficiency of the system is still low, but it has the advantage that the operating cost is free, very low maintenance and pollution-free. Maximum power point tracking (MPPT) is a significant part of PV systems. This paper presents a novel intelligent MPPT controller for PV systems. For the MPPT algorithm, an optimized fuzzy logic controller (FLC) using the Hopfield neural network is proposed. It utilizes an automatically tuned FLC membership function instead of the trial-and-error approach. The MPPT algorithm is implemented in a new variant of coupled inductor soft switching boost converter with high voltage gain to increase the converter output from the PV panel. The applied switching technique, which includes passive and active regenerative snubber circuits, reduces the insulated gate bipolar transistor switching losses. The proposed MPPT algorithm is implemented using the dSPACE DS1104 platform software on a DS1104 board controller. The prototype MPPT controller is tested using an agilent solar array simulator together with a 3？kW real PV panel. Experimental test results show that the proposed boost converter produces higher output voltages and gives better efficiency (90%) than the conventional boost converter with an RCD snubber, which gives 81% efficiency. The prototype MPPT controller is also found to be capable of tracking power from the 3？kW PV array about 2.4 times more than that without using the MPPT controller. 1. Introduction Energy generation based on renewable energy resources has received a great attention. Photovoltaic (PV) system is one of the promising renewable energy technologies. The photovoltaic (PV) generation system is a promising renewable, clean, and environmentally friendly source of energy [1]. Each solar cell produces only about one-half volt of electricity, and dozens of individual solar cells are interconnected in a sealed, weatherproof package called a PV module [2]. PV modules can be connected in series, parallel, or both into what is called a PV array. This PV array is connected to a power conditioner and then to a load or grid tie as a grid connected PV system. In general, the two main problems with PV power generation systems are the low conversion efficiency and that electrical power generated by a typical PV panel varies with weather conditions. Thus, many studies on enhancing the energy-generation efficiency of PV applications have been carried out [3]. A PV generation system should operate at its
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