H7 three phase transformerless inverter for photovoltaic grid-tied system with maximum power point operation

Abstract

<span lang="EN-US">One of the most important and common parts of the modern power systems is the grid-connected photovoltaic (PV) systems. Recently, these systems have gotten a big revolution due to the introduction of the transformerless inverters. It has the merits of small size, low cost, and high efficiency. However, transformerless inverters has a general safety problem related to the earth leakage current. Various researches were directed toward evolving their performance and diminishing the leakage current to the standard limits. This article proposes an application of the H7 controller to a PV powered grid-tied three phase transformerless inverter. The transformerless inverter is linked with the grid through a boost converter. The boost converter inductance is rearranged and divided to reduce the earth leakage current of the system. simulations are carried out for the proposed H7 PV grid-tied system and for a system that uses the conventional three phase inverter. The simulation results show that the H7 inverter provides lower leakage current, higher efficiency, and lower total harmonic distortion (THD) compared to the conventional three phase inverter.</span>

Fabrication and experimental study of transformer 400 V with a simple rectifier circuit design

“…Recently, this system has gotten a big revolution due to the introduction of transformer less inverter. It has the benefits of small size, low cost and high efficiency [13]. In the utilization of photovoltaic (PV), a DC voltage converter is needed as a voltage regulator output [14].…”

An Efficient Grid Connected Photovoltaic System Based on H6 Transformer-less Inverter

“…To overcome the leakage current problems, the so-called transformer-less inverters are utilized. Many topologies of transformer-less inverters are presented in literature including three phase and single-phase transformer-less inverters [10]- [17]. The main feature of transformer-less inverters is to decouple the photovoltaic arrays from the grid either on the dc side (PV array side) as in H5, H6 and H7 transformer-less inverters or on the dc side (grid side) as in the highly efficient and reliable inverter concept inverter (HERIC) transformerless inverter.…”