Query: H5 topology inverter

Candidate papers:

abstract: A generalized circuit topology of multilevel voltage source inverters which is based on a direct extension of the three level inverter to higher level is proposed. The circuit topologies up to five level are presented. The proposed multilevel inverter can realize any multilevel pulsewidth modulation (PWM) scheme which leads to harmonic reduction and provides full utilization of semiconductor devices like GTOs, especially in the high power range where high voltage can be applied. The capacitor voltage balancing problem is discussed and a circuit remedy for such a problem is given.<ETX>
author_names: N S Choi

Je-Hyung Cho

Gyu-Hyeong Cho
title: A general circuit topology of multilevel inverter
venue: PESC '91 Record 22nd Annual IEEE Power Electronics Specialists Conference
year: 1991

abstract: There is a strong trend in the photovoltaic inverter technology to use transformerless topologies in order to acquire higher efficiencies combining with very low ground leakage current. In this paper, a new topology, based on the H bridge with a new ac bypass circuit consisting of a diode rectifier and a switch with clamping to the dc midpoint, is proposed. The topology is simulated and experimentally validated, and a comparison with other existing topologies is performed. High conversion efficiency and low leakage current are demonstrated.
author_names: Tamas Kerekes

Remus Teodorescu

Pedro Rodriguez

Gerardo Vazquez

Emiliano Aldabas
title: A New High Efficiency Single Phase Transformerless PV Inverter Topology
venue: IEEE Transactions on Industrial Electronics
year: 2011

abstract: This paper presents an overview of single phase inverters developed for small distributed power generators. The functions of inverters in distributed power generation (DG) systems include dc ac conversion, output power quality assurance, various protection mechanisms, and system controls. Unique requirements for small distributed power generation systems include low cost, high efficiency and tolerance for an extremely wide range of input voltage variations. These requirements have driven the inverter development toward simpler topologies and structures, lower component counts, and tighter modular design. Both single stage and multiple stage inverters have been developed for power conversion in DG systems. Single stage inverters offer simple structure and low cost, but suffer from a limited range of input voltage variations and are often characterized by compromised system performance. On the other hand, multiple stage inverters accept a wide range of input voltage variations, but suffer from high cost, complicated structure and low efficiency. Various circuit topologies are presented, compared, and evaluated against the requirements of power decoupling and dual grounding, the capabilities for grid connected or/and stand alone operations, and specific DG applications in this paper, along with the identification of recent development trends of single phase inverters for distributed power generators.
author_names: Josep Bordonau

T Shimizu
title: Topologies of single phase inverters for small distributed power generators: an overview
venue: IEEE Transactions on Power Electronics
year: 2004

abstract: Transformerless photovoltaic (PV) grid connected inverters have become more and more popular in distributed PV power generation systems due to the advantages on high efficiency, low cost, and small size. However, common mode (CM) current in the transformerless PV inverters can result in serious electromagnetic interference and insecurity, which will further reduce the reliability of the PV inverter systems. In this paper, an improved H5 topology, namely H5 D topology, is proposed, in which a clamping diode is added on the basis of H5 topology to eliminate the CM voltage fluctuation in H5 topology. Further, the PSIM simulation results of the H5 D topology and H5 topology are given and compared, especially, the performance of H5 D topology for CM current suppression is presented and analyzed concretely. Finally, the experimental prototypes of the H5 D topology and H5 topology are built and tested, and the experimental results validate the advantages of the H5 D topology. The proposed H5 D topology provides a new practical topology for distributed PV grid connected power generation systems.
author_names: Hong Li

Yangbin Zeng

Bo Zhang

Trillion Q Zheng

Ruixiang Hao

Zhichang Yang
title: An Improved H5 Topology With Low Common Mode Current for Transformerless PV Grid Connected Inverter
venue: IEEE Transactions on Power Electronics
year: 2019

abstract: This paper analyzes and compares three transformerless photovoltaic inverter topologies for three phase grid connection with the main focus on the safety issues that result from the lack of galvanic isolation. A common mode model, valid at frequencies lower than 50 kHz, is adopted to study the leakage current paths. The model is validated by both simulation and experimental results. These will be used to compare the selected topologies, and to explain the influence of system unbalance and the neutral conductor inductance on the leakage current. It will be demonstrated that the later has a crucial influence. Finally, a comparison of the selected topologies is carried out, based on the adopted modulation, connection of the neutral and its inductance, effects of unbalance conditions, component ratings, output voltage levels, and filter size.
author_names: Tamas Kerekes

Remus Teodorescu

Christian Klumpner

Mark Sumner

Dan Floricau

Pedro Rodriguez
title: Evaluation of Three Phase Transformerless Photovoltaic Inverter Topologies
venue: IEEE Transactions on Power Electronics
year: 2009

abstract: The three dimensional structure of an HNF 3/fork head DNA recognition motif complexed with DNA has been determined by X ray crystallography at 2.5 A resolution. This a/b protein binds B DNA as a monomer, through interactions with the DNA backbone and through both direct and water mediated major and minor groove base contacts, inducing a 13deg bend. The transcription factor fold is very similar to the structure of histone H5. In its amino terminal half, three a helices adopt a compact structure that presents the third helix to the major groove. The remainder of the protein includes a twisted, antiparallel b structure and random coil that interacts with the minor groove.
author_names: Kirk L Clark

Elaine D Halay

Eseng Lai

Stephen K Burley
title: Co crystal structure of the HNF 3/fork head DNA recognition motif resembles histone H5
venue: Nature
year: 1993

abstract: Preface 1. General Topology 2. Diferentiable Manifolds 3. 1= Fundamental Group 4. Homology Theory 5. Cohomology 6. Products and Duality 7. Homotopy Theory Appendices A E Bibliography Index of Symbols Index
author_names: Glen E Bredon
title: Topology and geometry
year: 1993

abstract: Abstract In order to improve the efficiency and reduce the cost of a photovoltaic system, the use of transformerless photovoltaic inverters is an alternative of increasing interest. However, this topology needs to be studied in detail, as it presents some problems related to the galvanic connection between the grid and the photovoltaic generator (e.g. efficiency degradation and safety problems) In this paper, a review of grid connected single phase photovoltaic inverters based on transformerless topologies has been carried out. On the one hand, some alternatives based on classical topologies have been presented. On the other hand, alternatives based on multi level inverter topologies have been studied, showing up that no leakage current is generated in comparison to classical topologies.
author_names: Ivan Patrao

Emilio Figueres

Fran Gonzalez-Espin

Gabriel Garcera
title: Transformerless topologies for grid connected single phase photovoltaic inverters
year: 2011

abstract: A new neutral point clamped pulsewidth modulation (PWM) inverter composed of main switching devices which operate as switches for PWM and auxiliary switching devices to clamp the output terminal potential to the neutral point potential has been developed. This inverter output contains less harmonic content as compared with that of a conventional type. Two inverters are compared analytically and experimentally. In addition, a new PWM technique suitable for an ac drive system is applied to this inverter. The neutral point clamped PWM inverter adopting the new PWM technique shows an excellent drive system efficiency, including motor efficiency, and is appropriate for a wide range variable speed drive system.
author_names: Akira Nabae

Isao Takahashi

Hirofumi Akagi
title: A New Neutral Point Clamped PWM Inverter
venue: IEEE Transactions on Industry Applications
year: 1981

abstract: Transformerless photovoltaic systems are one of the best options to connect a photovoltaic system to the electrical grid given their high efficiency, low cost, small size and low weight regarding their counterparts based on a transformer. In this paper a multilevel single phase inverter is aimed to link a photovoltaic generator with the electrical grid with reduced common mode current. A sinusoidal based modulation strategy is also presented which focus not only in the reduction of the common mode current but also in the reduction of the switching and conduction losses. Five voltage levels are obtained at the inverter output, therefore, a good behavior is achieved regarding harmonic distortion. Numerical results show that the proposed inverter and modulation strategy give a reduced common mode current and low harmonic distortion which is suitable for transformerless photovoltaic systems.
author_names: Gerardo Vazquez

Panfilo R Martinez

Jose M Sosa

Gerardo Escobar

Mario A Juarez

Andres A Valdez
title: H5 HERIC based transformerless multilevel inverter for single phase grid connected PV systems
venue: IECON 2015 41st Annual Conference of the IEEE Industrial Electronics Society
year: 2015