Pub Date : 2019-12-01DOI: 10.1109/COBEP/SPEC44138.2019.9065892
Matheos C. Wermuth, Amanda C. Maia, Richard G. Cornelius, Guilherme S. da Silva
This paper presents the comparison of two modulation techniques, a carrier based PDPWM with third harmonic injection, and a double-sided modulation, for the Three Level Diode-Clamped Split-Source Inverter (3L-DC-SSI) and shows each benefits and drawbacks. The 3L-DC-SSI is applied to the electrical vehicle (EV) context since it has the advantage of operating with two isolated DC sources, being able to potentially ally the photovoltaic energy generation with an energy storing system commonly used in EVs. For this purpose, both modulation approaches are tested via simulation and the results are compared.
{"title":"Comparison Between Two Modulation Strategies for the 3L-DC-SSI","authors":"Matheos C. Wermuth, Amanda C. Maia, Richard G. Cornelius, Guilherme S. da Silva","doi":"10.1109/COBEP/SPEC44138.2019.9065892","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065892","url":null,"abstract":"This paper presents the comparison of two modulation techniques, a carrier based PDPWM with third harmonic injection, and a double-sided modulation, for the Three Level Diode-Clamped Split-Source Inverter (3L-DC-SSI) and shows each benefits and drawbacks. The 3L-DC-SSI is applied to the electrical vehicle (EV) context since it has the advantage of operating with two isolated DC sources, being able to potentially ally the photovoltaic energy generation with an energy storing system commonly used in EVs. For this purpose, both modulation approaches are tested via simulation and the results are compared.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79459055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-01DOI: 10.1109/COBEP/SPEC44138.2019.9065301
Marcos Vinicius Bressan, C. Rech, A. Batschauer
This work evaluates two capacitors design methodologies for Flying Capacitors Inverters. The first design methodology is developed through analysis of one switching period of the flying capacitor inverter. The second one analyses a complete output period of the inverter using the double Fourier series. Bolt methodologies use of the Phase-Shift Pulse Width Modulation. Experimental and numeric results verify the impacting of the two methodologies design in a five-level flying capacitor inverter.
{"title":"Impact of Capacitor Design Methodology on FC Inverters","authors":"Marcos Vinicius Bressan, C. Rech, A. Batschauer","doi":"10.1109/COBEP/SPEC44138.2019.9065301","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065301","url":null,"abstract":"This work evaluates two capacitors design methodologies for Flying Capacitors Inverters. The first design methodology is developed through analysis of one switching period of the flying capacitor inverter. The second one analyses a complete output period of the inverter using the double Fourier series. Bolt methodologies use of the Phase-Shift Pulse Width Modulation. Experimental and numeric results verify the impacting of the two methodologies design in a five-level flying capacitor inverter.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79757552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-01DOI: 10.1109/COBEP/SPEC44138.2019.9065311
E. Y. Sakô, João Lucas de Souza Silva, Daniel de Bastos Mesquita, Rafael Espino Campos, H. S. Moreira, Marcelo Gradella Villalva
With the diffusion of the implantation of photovoltaic systems, it became necessary to research to increase efficiency and improve the payback of the investment. In this way, losses in photovoltaic systems are an obstacle, and among the several losses, losses by mismatch can be highlighted. Thus, the paper proposes to collect in literature and classify the causes and to point out the solutions for mismatch losses in a PV system, and posteriorly a case study on a PV system comparing the PV modules with dirt and clean. An I-V curve tracer was used to perform measurements with better accuracy. As a result, the mismatch losses happened in the photovoltaic system in the test and had an amplification when the photovoltaic modules were soiling, in both cases, limited the photovoltaic system of reach maximum power. Therefore, it has been shown that mismatch losses can occur in several ways, and can considerably influence the performance of a photovoltaic system.
{"title":"Concepts and Case Study of Mismatch Losses in Photovoltaic Modules","authors":"E. Y. Sakô, João Lucas de Souza Silva, Daniel de Bastos Mesquita, Rafael Espino Campos, H. S. Moreira, Marcelo Gradella Villalva","doi":"10.1109/COBEP/SPEC44138.2019.9065311","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065311","url":null,"abstract":"With the diffusion of the implantation of photovoltaic systems, it became necessary to research to increase efficiency and improve the payback of the investment. In this way, losses in photovoltaic systems are an obstacle, and among the several losses, losses by mismatch can be highlighted. Thus, the paper proposes to collect in literature and classify the causes and to point out the solutions for mismatch losses in a PV system, and posteriorly a case study on a PV system comparing the PV modules with dirt and clean. An I-V curve tracer was used to perform measurements with better accuracy. As a result, the mismatch losses happened in the photovoltaic system in the test and had an amplification when the photovoltaic modules were soiling, in both cases, limited the photovoltaic system of reach maximum power. Therefore, it has been shown that mismatch losses can occur in several ways, and can considerably influence the performance of a photovoltaic system.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80684768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-01DOI: 10.1109/COBEP/SPEC44138.2019.9065650
Khristian M. de Andrade, Hugo E. Santos, Wellington M. Vilela, T. E. P. de Almeida, G. T. de Paula
This paper presents PeMSyn, a free and open source graphical user interface based in Matlab/FEMM, for the design and simulation of Permanent Magnet Synchronous Machines. PeMSyn aggregates several functionalities normally found separated in other similar softwares, such as: automation of the drawing and sizing of Permanent Magnet Machines, winding design, Finite Element Analysis, pole segmentation analysis and performance assessment of Permanent Magnet Machines. PeMSyn is also modular, allowing the user to employ each one of these features individually. Moreover, it can be easily translated to any language by means of a language file and allows adding other machine topologies.This paper discusses each one of the modules in detail, the equations used in the design process, input parameters and output results, as well as an application example.
{"title":"PeMSyn: a Free Software to Assist the Design and Performance Assessment of Permanent Magnets Synchronous Machines","authors":"Khristian M. de Andrade, Hugo E. Santos, Wellington M. Vilela, T. E. P. de Almeida, G. T. de Paula","doi":"10.1109/COBEP/SPEC44138.2019.9065650","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065650","url":null,"abstract":"This paper presents PeMSyn, a free and open source graphical user interface based in Matlab/FEMM, for the design and simulation of Permanent Magnet Synchronous Machines. PeMSyn aggregates several functionalities normally found separated in other similar softwares, such as: automation of the drawing and sizing of Permanent Magnet Machines, winding design, Finite Element Analysis, pole segmentation analysis and performance assessment of Permanent Magnet Machines. PeMSyn is also modular, allowing the user to employ each one of these features individually. Moreover, it can be easily translated to any language by means of a language file and allows adding other machine topologies.This paper discusses each one of the modules in detail, the equations used in the design process, input parameters and output results, as well as an application example.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77851534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-01DOI: 10.1109/COBEP/SPEC44138.2019.9065377
Ê. C. Resende, Henrique T. M. Carvalho, F. C. Melo, E. Coelho, G. B. de Lima, L. D. de Freitas
In Grid-Tied Distributed Generation systems (GTDG), the islanding phenomena is a fundamental subject, since it can possibly lead to safety hazards for the line workers during maintenance and damage to equipment. Therefore, it is required that GTDG have anti-islanding techniques, which can be passive and/or active. This paper focuses on the computational implementation of three active anti-islanding techniques based on the frequency drift of the injected current of the inverter. These methods are the Classic Active Frequency Drift (AFD), AFD with Positive Feedback (AFDPF) and AFD with Pulsating Chopping Factor (AFDPCF). For the tests carried out, was considered a PV system of 1 kWp using a VSI inverter, evaluating the time for detecting the islanding, the NDZ size and the THDi caused by the anti-islanding method. The AFDPCF proved to present reduced NDZ, the SFS performed the faster islanding detection and both presented reduced THDi , for all the analyzed cases.
{"title":"A Performance Analysis of Active Anti-Islanding Methods Based on Frequency Drift","authors":"Ê. C. Resende, Henrique T. M. Carvalho, F. C. Melo, E. Coelho, G. B. de Lima, L. D. de Freitas","doi":"10.1109/COBEP/SPEC44138.2019.9065377","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065377","url":null,"abstract":"In Grid-Tied Distributed Generation systems (GTDG), the islanding phenomena is a fundamental subject, since it can possibly lead to safety hazards for the line workers during maintenance and damage to equipment. Therefore, it is required that GTDG have anti-islanding techniques, which can be passive and/or active. This paper focuses on the computational implementation of three active anti-islanding techniques based on the frequency drift of the injected current of the inverter. These methods are the Classic Active Frequency Drift (AFD), AFD with Positive Feedback (AFDPF) and AFD with Pulsating Chopping Factor (AFDPCF). For the tests carried out, was considered a PV system of 1 kWp using a VSI inverter, evaluating the time for detecting the islanding, the NDZ size and the THDi caused by the anti-islanding method. The AFDPCF proved to present reduced NDZ, the SFS performed the faster islanding detection and both presented reduced THDi , for all the analyzed cases.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73820596","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-01DOI: 10.1109/COBEP/SPEC44138.2019.9065634
Walquiria N. Silva, J. G. de Oliveira, B. Dias, L. D. de Oliveira
This paper presents the operation and modelling of gas microturbines as Distributed Generation (DG) systems. The studied system consists of a gas microturbine linked to Permanent Magnet Synchronous Generator (PMSG), which is connected to a back-to-back converter. The purpose of this study is to analyze the dynamic behaviour of gas microturbines in a simple and operative model so that the results can be used to investigate the applicability of energy generation. The development of the system will be validated through simulation, using the Simulink-MATLAB® software, whose obtained results will verify the system’s operation and suggest possible applications.
{"title":"Gas Microturbines for Distributed Generation System","authors":"Walquiria N. Silva, J. G. de Oliveira, B. Dias, L. D. de Oliveira","doi":"10.1109/COBEP/SPEC44138.2019.9065634","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065634","url":null,"abstract":"This paper presents the operation and modelling of gas microturbines as Distributed Generation (DG) systems. The studied system consists of a gas microturbine linked to Permanent Magnet Synchronous Generator (PMSG), which is connected to a back-to-back converter. The purpose of this study is to analyze the dynamic behaviour of gas microturbines in a simple and operative model so that the results can be used to investigate the applicability of energy generation. The development of the system will be validated through simulation, using the Simulink-MATLAB® software, whose obtained results will verify the system’s operation and suggest possible applications.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74137549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-01DOI: 10.1109/COBEP/SPEC44138.2019.9065481
E. V. Stangler, F. Neves, F. Bradaschia, M. Mezaroba, F. J. Zimann, A. Batschauer
The unified power quality conditioner has been considered one of the most complete solutions to power quality related issues. Thus, the development of control strategies that improve its performance has gained increasing research interest. This paper presents an enhanced control scheme for ensuring an improved compensation performance for the dual unified power quality conditioner (iUPQC). The basics of the control implementation, the reference generators and the control loops specifications of both converters are discussed in detail. Besides, the design step of the controllers is carefully explained in order to allow its reproduction. Furthermore, the complete control scheme is validated through experimental results using a three-phase three-wire iUPQC prototype.
{"title":"Implementation of a iUPQC control scheme for ensuring an improved compensation performance","authors":"E. V. Stangler, F. Neves, F. Bradaschia, M. Mezaroba, F. J. Zimann, A. Batschauer","doi":"10.1109/COBEP/SPEC44138.2019.9065481","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065481","url":null,"abstract":"The unified power quality conditioner has been considered one of the most complete solutions to power quality related issues. Thus, the development of control strategies that improve its performance has gained increasing research interest. This paper presents an enhanced control scheme for ensuring an improved compensation performance for the dual unified power quality conditioner (iUPQC). The basics of the control implementation, the reference generators and the control loops specifications of both converters are discussed in detail. Besides, the design step of the controllers is carefully explained in order to allow its reproduction. Furthermore, the complete control scheme is validated through experimental results using a three-phase three-wire iUPQC prototype.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81732531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-01DOI: 10.1109/COBEP/SPEC44138.2019.9065511
Francesco Toniolo, Qing Liu, T. Caldognetto, S. Buso, G. Spiazzi
This paper describes the implementation of a digital current controller for a Bidirectional Interleaved Boost converter with Coupled Inductors (BIBCI). The final goal of the project is to develop a complete, high efficiency, battery management system (BMS). In order to do that, an optimized, triple phase shift (TPS) digital PWM strategy is used to maximize the BIBCI conversion efficiency. On top of that, a battery current controller is implemented, whose dynamic modeling is analyzed. The controller design procedure is then explained. Experimental results, taken on a 1.5 kW converter prototype, validate the theoretical analysis and control design procedure.
{"title":"Digital Current Control for a Bidirectional Interleaved Boost Converter with Coupled Inductors","authors":"Francesco Toniolo, Qing Liu, T. Caldognetto, S. Buso, G. Spiazzi","doi":"10.1109/COBEP/SPEC44138.2019.9065511","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065511","url":null,"abstract":"This paper describes the implementation of a digital current controller for a Bidirectional Interleaved Boost converter with Coupled Inductors (BIBCI). The final goal of the project is to develop a complete, high efficiency, battery management system (BMS). In order to do that, an optimized, triple phase shift (TPS) digital PWM strategy is used to maximize the BIBCI conversion efficiency. On top of that, a battery current controller is implemented, whose dynamic modeling is analyzed. The controller design procedure is then explained. Experimental results, taken on a 1.5 kW converter prototype, validate the theoretical analysis and control design procedure.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82230090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-01DOI: 10.1109/COBEP/SPEC44138.2019.9065406
Matheus K. Ferst, Hugo F. M. de Figueiredo, G. Denardin
The growth of Renewable Distributed Generations (RDG) presents both, a solution to common problems of traditional energy sources - such as the environmental impact and losses in transmission and distribution - and a challenge to appropriate control a large number of Distributed Energy Resources (DERs). The feasibility of such control depends on adequate communication protocols that, among other features, need to address the security requirements of DER applications. Modbus/TLS was presented in previous work as a possible protocol for direct DER communications and analyzed with respect to bulk data transfer. This paper extends such analysis, evaluating the connection time for multiple key exchange algorithms configurations, discussing possible impacts and proposing alternatives for environments where the observed connection times are prohibitive.
{"title":"Connection Time in Modbus/TLS for Secure Communications on Photovoltaic Systems","authors":"Matheus K. Ferst, Hugo F. M. de Figueiredo, G. Denardin","doi":"10.1109/COBEP/SPEC44138.2019.9065406","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065406","url":null,"abstract":"The growth of Renewable Distributed Generations (RDG) presents both, a solution to common problems of traditional energy sources - such as the environmental impact and losses in transmission and distribution - and a challenge to appropriate control a large number of Distributed Energy Resources (DERs). The feasibility of such control depends on adequate communication protocols that, among other features, need to address the security requirements of DER applications. Modbus/TLS was presented in previous work as a possible protocol for direct DER communications and analyzed with respect to bulk data transfer. This paper extends such analysis, evaluating the connection time for multiple key exchange algorithms configurations, discussing possible impacts and proposing alternatives for environments where the observed connection times are prohibitive.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87763299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-12-01DOI: 10.1109/COBEP/SPEC44138.2019.9065544
I. V. Bessa, R. L. Medeiros, I. Bessa, Florindo A. C. Ayres Junior, Kevin E. Lucas
DC-DC switching power converters exhibit the important characteristic of almost-perfect regulation at the output terminals independent of the input perturbations. However, such characteristic reflects at the input terminal as a constant power load (CPL). Microgrids (MGs) consists of multiple converters to satisfy the different voltage levels that loads need and stability problems are caused due to the interaction of Point-of-Load (POL) converters. In this context, this paper focuses on the stability analysis of POL converters as CPLs. In particular, POL converters are modeled using boost and buck converter topologies and the stabilization of POL converters is performed with different classic and modern control strategies, such as output feedback and state feedback. The performance analysis of the controllers is carried out using the Integral Squared Error (ISE), the Integral Time-weighted Squared Error (ITSE) and the Integral Squared of Control Signal (ISSC) performance indices.
{"title":"Stabilization of DC Microgrids with Point-of-Load Converters as Constant Power Loads","authors":"I. V. Bessa, R. L. Medeiros, I. Bessa, Florindo A. C. Ayres Junior, Kevin E. Lucas","doi":"10.1109/COBEP/SPEC44138.2019.9065544","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065544","url":null,"abstract":"DC-DC switching power converters exhibit the important characteristic of almost-perfect regulation at the output terminals independent of the input perturbations. However, such characteristic reflects at the input terminal as a constant power load (CPL). Microgrids (MGs) consists of multiple converters to satisfy the different voltage levels that loads need and stability problems are caused due to the interaction of Point-of-Load (POL) converters. In this context, this paper focuses on the stability analysis of POL converters as CPLs. In particular, POL converters are modeled using boost and buck converter topologies and the stabilization of POL converters is performed with different classic and modern control strategies, such as output feedback and state feedback. The performance analysis of the controllers is carried out using the Integral Squared Error (ISE), the Integral Time-weighted Squared Error (ITSE) and the Integral Squared of Control Signal (ISSC) performance indices.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87116498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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