High-Efficient Photovoltaic Power Optimizer Based on the Intrinsic Resonance and Coupled Inductors

Reducing switching losses through resonance is an effective way to improve the efficiency of a solar power optimizer. In fact, in comparison with the traditional converters, the resonance-based solar power optimizer can offer considerable reliability and efficiency at reduced cost if unnecessary elements in its configuration are removed. In this article, a new photovoltaic boost power optimizer is introduced based on the resonance between the converter inductor and the output capacitance of the MOSFET leading to a reduction in the switching losses of the MOSFET. Using this method, the cost of the converter decreases compared with traditional methods that employ additional elements to use the resonance in the system. In the proposed converter, the MOSFET is switched on when the resonant voltage across it reaches zero or a minimum value; therefore, the switching losses decrease significantly. Also, the proposed boost power optimizer operates in a critical conduction mode (CRM) to decrease the switching losses. In addition to the reduction of MOSFET switching losses, other losses consisting of inductor copper loss, diode conduction loss, and conducting loss of MOSFET are reduced so that converter efficiency increases considerably. The proposed technique is experimentally validated using a prototype. Experimental results demonstrated that the efficiency of the boost power optimizer is as high as 98%.