A Novel Single-Phase Switched-Capacitor Based 5-level Inverter Topology Featuring Voltage Boosting Capability and Common Mode Voltage Reduction

In this paper, a switched-capacitor multilevel inverter with voltage boosting and common-mode-voltage reduction capabilities is put forth. The proposed inverter is synthesized with one-half bridge and several switched-capacitor cells. Due to the voltage boosting and common-mode current reduction features, the proposed multilevel inverter is suitable for grid-connected PV applications. In addition, an analytical lifetime evaluation based on mission profile of the proposed inverter has been presented to derive lifetime distribution of semiconductors. Whereas in the proposed inverter, any components failure can bring the whole system to a shutdown. The series reliability model is used to estimate the lifetime of the overall system. The performance of the suggested multilevel inverter in grid-connected applications is verified through the simulation results using the grid-tied model in Matlab/Simulink. Moreover, the viability and feasibility of the presented inverter are proven by using a one kW lab-scaled prototype.

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Research on an Improved Single-Phase Unisolated Grid-Connected Photovoltaic Inverter

European Journal of Electrical Engineering ◽

10.18280/ejee.230205 ◽

2021 ◽

Vol 23 (2) ◽

pp. 123-130

Author(s):

Baoge Zhang ◽

Deyu Hong

Keyword(s):

Leakage Current ◽

Single Phase ◽

Current Problem ◽

Input Voltage ◽

Common Mode ◽

Common Mode Voltage ◽

Voltage Clamping ◽

The Common ◽

Simulation Results ◽

Inverter Topology

An improved single-phase unisolated grid-connected photovoltaic inverter topology is proposed to solve the common mode leakage current problem of unisolated grid-connected photovoltaic inverters. By analyzing the topology structure and voltage clamping principle of the improved inverter, the topology can maintain the same low input voltage as the full-bridge inverter, and ensure that the common-mode voltage in the continuation mode is clamped to the midpoint voltage of the bus, so as to effectively reduce the common-mode leakage current caused by the common-mode voltage suspension in the continuation mode. Moreover, the common-mode leakage current of the improved topology is smaller than that of the traditional H6-2D topology at similar conversion efficiency. The simulation results on MATLAB /Simulink platform show that the topology is feasible and effective.

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A Novel Inverter Topology for Single-Phase Transformerless PV System

Active and Passive Electronic Components ◽

10.1155/2016/1962438 ◽

2016 ◽

Vol 2016 ◽

pp. 1-6

Author(s):

Haiyan Cao

Keyword(s):

Leakage Current ◽

Single Phase ◽

High Efficiency ◽

Low Cost ◽

Experimental Tests ◽

Pv System ◽

Common Mode ◽

Common Mode Voltage ◽

The Common ◽

Inverter Topology

Transformerless photovoltaic (PV) power system is very promising due to its low cost, small size, and high efficiency. One of its most important issues is how to prevent the common mode leakage current. In order to solve the problem, a new inverter is proposed in this paper. The system common mode model is established, and the four operation modes of the inverter are analyzed. It reveals that the common mode voltage can be kept constant, and consequently the leakage current can be suppressed. Finally, the experimental tests are conducted. The experimental results verify the effectiveness of the proposed solution.

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