A High Step-up Transformer-Less DC-DC Converter with Continuous Input Current

Recently, renewable and sustainable energy sources such as PV are utilized as clean energy sources however, these energy sources have a low output voltage, and in high voltage applications high gain DC-DC converters are applied to enhance the output voltage of these types of energy sources. In this article, a non-isolated step-up DC-DC converter by a coupled inductor is introduced and also analyzed. Unlike previous DC-DC converters, this converter provides high voltage gain with low turn ratio, which reduces the core size, volume and weight of the converter and also reduces the cost of the system. Also, by coupled inductor turn's ratio reduction, the voltage stress of the semiconductor elements is reduced subsequently. A passive clamp circuit is also applied in the proposed converter, which boosts the converter voltage gain and also, reduces the voltage across of the switches. To demonstrate the benefits of the presented topology, a laboratory model is fabricated with 20V input and 200V output voltages and power rate of 200W in 25 kHz operation frequency.