Comprehensive analysis on topologies for limiting leakage current in transformerless inverter

With the evolution of science and technology, human beings' demand for electric energy has increased rapidly. Traditional power generation methods such as using fossil fuel will result in serious greenhouse gases emitting, which leads to an intensification of the global greenhouse effect. Using clean energy to replace traditional power generation methods becomes urgent. As a reliable energy source, sunlight could continuously provide energy for human beings and Solar energy has accounted for a large proportion of new energy. Solar energy is converted into Direct Current (DC) by solar panels and the power transmitted from the power grid to factories and houses requires Alternating Current (AC), in this condition, inverters that could convert DC to AC are important components in photovoltaic (PV) systems. As the development of inverter technology gradually matures, inverters begin to develop with the characteristics of small, low-cost, and transformerless. This article introduces a common technical problem encountered in developing transformerless inverters-the generation of leakage current. Several different transformerless inverter topologies are compared to find reliable methods to limit leakage current, and some suggestions are raised for the future development of transformerless inverters.