Pub Date : 2019-12-01DOI: 10.1109/COBEP/SPEC44138.2019.9065338
J. Friebe, Siqi Lin, L. Fauth, Tobias Brinker
Premagnetization can be used to reduce the size, weight and losses of inductors. Due to the non-symmetric LIcurve of these inductors, they are typically only used in unidirectional dc converters. This paper introduces and discusses three topologies with premagnetized inductors for dc-ac conversion, including measurement results for one topology.
{"title":"Premagnetized Inductors in Single Phase dc-ac and ac-dc Converters","authors":"J. Friebe, Siqi Lin, L. Fauth, Tobias Brinker","doi":"10.1109/COBEP/SPEC44138.2019.9065338","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065338","url":null,"abstract":"Premagnetization can be used to reduce the size, weight and losses of inductors. Due to the non-symmetric LIcurve of these inductors, they are typically only used in unidirectional dc converters. This paper introduces and discusses three topologies with premagnetized inductors for dc-ac conversion, including measurement results for one topology.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"3 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75543975","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/SPEC44138.2019.9065764
Clovis N. L. Gajo, Arendt Wintrich, Paul Drexhage
Methods to estimate the lifetime of Power Semiconductor Modules, the typical aging factors, how they act, and some of the new improvement technologies that lead to higher lifetime.
{"title":"Predicting the Life Time of Power Semiconductor Modules","authors":"Clovis N. L. Gajo, Arendt Wintrich, Paul Drexhage","doi":"10.1109/COBEP/SPEC44138.2019.9065764","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065764","url":null,"abstract":"Methods to estimate the lifetime of Power Semiconductor Modules, the typical aging factors, how they act, and some of the new improvement technologies that lead to higher lifetime.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"299 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73199002","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/SPEC44138.2019.9065629
A. A. de Melo Bento, Raphael Perci Santiago
Photovoltaic panels are a low efficiency energy source. These require a relative large area in order to generate a specified output power and operate subject to uncontrollable environmental conditions. Photovoltaic panel emulators offer several important advantages in the context of testing MPPT techniques and static converter controller performance besides contributing to educational tool. This paper proposes a photovoltaic emulator whose the main characteristics are low electric inertia, flexibility, simplicity, low cost and robustness while maintaining a good approximation of the solar I-V profile. The design procedure is detailed and experimental results are carried out to confirm the feasibility of proposal.
{"title":"A Low Cost Photovoltaic Panel Emulator","authors":"A. A. de Melo Bento, Raphael Perci Santiago","doi":"10.1109/COBEP/SPEC44138.2019.9065629","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065629","url":null,"abstract":"Photovoltaic panels are a low efficiency energy source. These require a relative large area in order to generate a specified output power and operate subject to uncontrollable environmental conditions. Photovoltaic panel emulators offer several important advantages in the context of testing MPPT techniques and static converter controller performance besides contributing to educational tool. This paper proposes a photovoltaic emulator whose the main characteristics are low electric inertia, flexibility, simplicity, low cost and robustness while maintaining a good approximation of the solar I-V profile. The design procedure is detailed and experimental results are carried out to confirm the feasibility of proposal.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"11 1","pages":"1-5"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73277299","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/SPEC44138.2019.9065607
Rafael César Nolasco, V. F. Mendes
The interest in studying electrochemical batteries in many applications is rising in the last years, due to increasing applications of storage systems in which batteries have a crucial role. For example, one can cite electric vehicles and in the future power systems, where storage can be used for load leveling, power variation damping and power quality improvement. Although batteries are a component known for a long time, modelling them is a very complex task. There is not a general model easily applicable in every situation. To address this issue, this paper presents the approaches commonly used in battery modelling and develops one model to represent the behavior of battery voltage and capacity during a discharge and charge cycle. Furthermore, another model is used to predict the lifetime and the degradation. These models are developed in order to simulate small scale battery systems for Demand Side Management applications with PV generation.
{"title":"Modeling of Electrochemical Batteries Behavior and Lifetime Degradation for PV Applications","authors":"Rafael César Nolasco, V. F. Mendes","doi":"10.1109/COBEP/SPEC44138.2019.9065607","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065607","url":null,"abstract":"The interest in studying electrochemical batteries in many applications is rising in the last years, due to increasing applications of storage systems in which batteries have a crucial role. For example, one can cite electric vehicles and in the future power systems, where storage can be used for load leveling, power variation damping and power quality improvement. Although batteries are a component known for a long time, modelling them is a very complex task. There is not a general model easily applicable in every situation. To address this issue, this paper presents the approaches commonly used in battery modelling and develops one model to represent the behavior of battery voltage and capacity during a discharge and charge cycle. Furthermore, another model is used to predict the lifetime and the degradation. These models are developed in order to simulate small scale battery systems for Demand Side Management applications with PV generation.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"10 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73898528","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/SPEC44138.2019.9065546
M. M. Lumertz, C. D. de Oliveira, A. G. de Castro, P. Guazzelli, M.L. de Aguiar, J. Monteiro
Permanent magnetic synchronous machines with trapezoidal back-electromotive force and six-step operation, also known as brushless direct current motors, have high torque undulations because needed current waveform can’t be provided. Proper vector control techniques used to reduce chattering, are high dependent on machine parameters and are complex to implement on real applications. Sliding Mode and Pseudo Sliding Mode are controllers with high dynamical performance and simple implementation, but increase torque undulations in machine control applications. On the other hand, wavelet multiresolution controllers have the feature of chattering reduction, but are complex to tune and analyze, due to the number of parallel detail and approximation coefficients used. This works proposes a simplified wavelet controller, replacing approximation coefficients with a proportional controller. This controller was used to design a proper sliding manifold for a sliding mode speed control, on a BLDC motor, without using machine parameters. A genetic algorithm was used to determine an optimum mother wavelet for a fixed decomposition level, leaving just one parameter to tune in future works. In results, an improvement to the proposed controller was suggested, for a controller with high dynamical and steady state performance, without torque undulations and easier to tune than wavelet multiresolution controllers.
{"title":"Proportional Wavelet Sliding Mode Controller for Torque Ripple Reduction in BLDC Motor","authors":"M. M. Lumertz, C. D. de Oliveira, A. G. de Castro, P. Guazzelli, M.L. de Aguiar, J. Monteiro","doi":"10.1109/COBEP/SPEC44138.2019.9065546","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065546","url":null,"abstract":"Permanent magnetic synchronous machines with trapezoidal back-electromotive force and six-step operation, also known as brushless direct current motors, have high torque undulations because needed current waveform can’t be provided. Proper vector control techniques used to reduce chattering, are high dependent on machine parameters and are complex to implement on real applications. Sliding Mode and Pseudo Sliding Mode are controllers with high dynamical performance and simple implementation, but increase torque undulations in machine control applications. On the other hand, wavelet multiresolution controllers have the feature of chattering reduction, but are complex to tune and analyze, due to the number of parallel detail and approximation coefficients used. This works proposes a simplified wavelet controller, replacing approximation coefficients with a proportional controller. This controller was used to design a proper sliding manifold for a sliding mode speed control, on a BLDC motor, without using machine parameters. A genetic algorithm was used to determine an optimum mother wavelet for a fixed decomposition level, leaving just one parameter to tune in future works. In results, an improvement to the proposed controller was suggested, for a controller with high dynamical and steady state performance, without torque undulations and easier to tune than wavelet multiresolution controllers.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"148 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73953648","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/SPEC44138.2019.9065543
Dênis de Castro Pereira, Everton Bernard Figueiredo Rabelo, P. S. Almeida, Guilherme Márcio Soares, F. L. Tofoli, Henrique Antônio Carvalho Braga
This work presents a performance evaluation concerning interleaved buck structures used to drive extra-high current (up to 12 A) chip-on-board (COB) light-emitting diodes (LEDs). The analysis is carried out employing nonideal elements in simulations so that a better and reliable approach can be obtained as close to real results as possible. Aiming at a thorough analysis of conduction losses at very high current levels in floodlighting applications, interleaved buck converters (IBCs) are employed to establish a comparative approach concerning global efficiency and component count for conventional and synchronous topologies. Furthermore, the 3-cell IBC is experimentally implemented to evaluate and compare the total losses for this very-high current lighting application.
{"title":"Efficiency Analysis for Interleaved Buck Converters Employed as Extra-High Current COB LED Drivers","authors":"Dênis de Castro Pereira, Everton Bernard Figueiredo Rabelo, P. S. Almeida, Guilherme Márcio Soares, F. L. Tofoli, Henrique Antônio Carvalho Braga","doi":"10.1109/COBEP/SPEC44138.2019.9065543","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065543","url":null,"abstract":"This work presents a performance evaluation concerning interleaved buck structures used to drive extra-high current (up to 12 A) chip-on-board (COB) light-emitting diodes (LEDs). The analysis is carried out employing nonideal elements in simulations so that a better and reliable approach can be obtained as close to real results as possible. Aiming at a thorough analysis of conduction losses at very high current levels in floodlighting applications, interleaved buck converters (IBCs) are employed to establish a comparative approach concerning global efficiency and component count for conventional and synchronous topologies. Furthermore, the 3-cell IBC is experimentally implemented to evaluate and compare the total losses for this very-high current lighting application.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"24 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84172844","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/SPEC44138.2019.9065745
Henrique J. Hoch, T. M. K. Faistel, M. D. da Silva, A. Andrade, M. Martins
Due to the low voltage of the solar panels source, DC-DC high voltage gain converters are required for photovoltaic generation systems. So a new high voltage gain dc–dc converter is proposed in this paper. The proposed converter is generated by association of standard boost converter with switched-capacitor technique and a coupled inductor. This proposed converter achieves high voltage gain with low duty cycle and low turns ratio of the coupled inductor. In addition, it may be pointed out that these features are achieved with a low number of components, current and voltage stress. To evaluate the performance of the proposed converter, a 200-W prototype was simulated.
{"title":"High Voltage Gain DC-DC Converter based on a Simple Configuration of Switched Capacitor and Coupled Inductor","authors":"Henrique J. Hoch, T. M. K. Faistel, M. D. da Silva, A. Andrade, M. Martins","doi":"10.1109/COBEP/SPEC44138.2019.9065745","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065745","url":null,"abstract":"Due to the low voltage of the solar panels source, DC-DC high voltage gain converters are required for photovoltaic generation systems. So a new high voltage gain dc–dc converter is proposed in this paper. The proposed converter is generated by association of standard boost converter with switched-capacitor technique and a coupled inductor. This proposed converter achieves high voltage gain with low duty cycle and low turns ratio of the coupled inductor. In addition, it may be pointed out that these features are achieved with a low number of components, current and voltage stress. To evaluate the performance of the proposed converter, a 200-W prototype was simulated.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"09 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82171871","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/SPEC44138.2019.9065559
Elienai O. Macedo, R. Dias, S. L. Barcelos, E. Watanabe
This paper proposes a control algorithm for unbalanced voltage compensation using the Dynamic Direct Voltage Controller (D2VC). An advantage of this device is the possibility of a online direct voltage control in distribution systems, rather than on-load tap changers or other indirect control schemes. The proposed algorithm is based on the instantaneous positive and negative sequence components in αβ-frame, dismissing the use of a Unified Three-Phase Processor (UTSP), consequently avoiding its complexity and excessive computational efforts, and the compensation reference signals are obtained using proportional plus resonant (PR) controllers. There is no need of using any synchronism algorithm, e.g. PLL, which means that the D2VC’s performance is independent of the dynamics of this type of synchronization circuit. Simulation results carried out in time domain using PSCAD/EMTDC are presented to show the effectiveness of the proposed solution.
{"title":"Unbalanced Voltage Mitigation using D2VC with Proportional Resonant Controller in αβ-Frame","authors":"Elienai O. Macedo, R. Dias, S. L. Barcelos, E. Watanabe","doi":"10.1109/COBEP/SPEC44138.2019.9065559","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065559","url":null,"abstract":"This paper proposes a control algorithm for unbalanced voltage compensation using the Dynamic Direct Voltage Controller (D2VC). An advantage of this device is the possibility of a online direct voltage control in distribution systems, rather than on-load tap changers or other indirect control schemes. The proposed algorithm is based on the instantaneous positive and negative sequence components in αβ-frame, dismissing the use of a Unified Three-Phase Processor (UTSP), consequently avoiding its complexity and excessive computational efforts, and the compensation reference signals are obtained using proportional plus resonant (PR) controllers. There is no need of using any synchronism algorithm, e.g. PLL, which means that the D2VC’s performance is independent of the dynamics of this type of synchronization circuit. Simulation results carried out in time domain using PSCAD/EMTDC are presented to show the effectiveness of the proposed solution.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"95 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80409190","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/SPEC44138.2019.9065711
S. L. Barcelos, José Gomes de Matos, L. A. de Souza Ribeiro
A power system served by alternative energy sources to be deployed separately from the conventional power grid must be able to form a local power grid (also called a Microgrids), in which the load of this grid must be served in such a way that the concern with the degradation of the Electric Power Quality (PQ) indices is evidenced through studies that aim to characterize the state of operation of such electrical grid. In this sense, the proposition of solutions to improve the quality and continuity of service of the isolated Microgrids with intermittent generation integrated are extremely important. In this work, the results of the development of a simulation modelling using the PSCAD / EMTDC software to analyze and evaluate the impacts of several integration scenarios of intermittent generators in the Microgrid installed at the Lençóis Island community are presented.
{"title":"Modelling and Analysis of the Isolated Microgrid Installed at the Lençóis Island using PSCAD/EMTDC","authors":"S. L. Barcelos, José Gomes de Matos, L. A. de Souza Ribeiro","doi":"10.1109/COBEP/SPEC44138.2019.9065711","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065711","url":null,"abstract":"A power system served by alternative energy sources to be deployed separately from the conventional power grid must be able to form a local power grid (also called a Microgrids), in which the load of this grid must be served in such a way that the concern with the degradation of the Electric Power Quality (PQ) indices is evidenced through studies that aim to characterize the state of operation of such electrical grid. In this sense, the proposition of solutions to improve the quality and continuity of service of the isolated Microgrids with intermittent generation integrated are extremely important. In this work, the results of the development of a simulation modelling using the PSCAD / EMTDC software to analyze and evaluate the impacts of several integration scenarios of intermittent generators in the Microgrid installed at the Lençóis Island community are presented.","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"40 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89575233","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/SPEC44138.2019.9065528
C. Pineda, J. Pereda, S. Neira, P. Bravo, J. Rodríguez, C. García
High voltage direct current (HVDC) transmission systems and low voltage direct current (LVDC) networks are becoming popular due to their advantages and present feasibility, mainly pushed by the advance in power electronics. However, one of the main drawbacks of dc networks is the lack of a dc-dc converter that performs as the ac transformer in terms of efficiency, reliability and high-step voltage ratio, specially in medium and high voltage. Modular multilevel converters are an attractive alternative because they can manage medium and high dc voltages with standard semiconductor devices, and they can achieve high efficiency with soft switching modulation, such as resonant, trapezoidal or triangular currents usually used in double active bridges (DAB). This paper proposes a novel generalized trapezoidal current mode applied to high step ratio Modular Multilevel dc-dc Converters. The proposed modulation increases the efficiency and achieves bidirectional control of the power, soft-switching and a natural balance of the voltage in the capacitors. The simulation results show the bidirectional operation and the capacitor voltage balance of the converter under different operating conditions with high efficiency (98.2%).
{"title":"Trapezoidal Current Mode for Bidirectional High Step Ratio Modular Multilevel dc-dc Converter","authors":"C. Pineda, J. Pereda, S. Neira, P. Bravo, J. Rodríguez, C. García","doi":"10.1109/COBEP/SPEC44138.2019.9065528","DOIUrl":"https://doi.org/10.1109/COBEP/SPEC44138.2019.9065528","url":null,"abstract":"High voltage direct current (HVDC) transmission systems and low voltage direct current (LVDC) networks are becoming popular due to their advantages and present feasibility, mainly pushed by the advance in power electronics. However, one of the main drawbacks of dc networks is the lack of a dc-dc converter that performs as the ac transformer in terms of efficiency, reliability and high-step voltage ratio, specially in medium and high voltage. Modular multilevel converters are an attractive alternative because they can manage medium and high dc voltages with standard semiconductor devices, and they can achieve high efficiency with soft switching modulation, such as resonant, trapezoidal or triangular currents usually used in double active bridges (DAB). This paper proposes a novel generalized trapezoidal current mode applied to high step ratio Modular Multilevel dc-dc Converters. The proposed modulation increases the efficiency and achieves bidirectional control of the power, soft-switching and a natural balance of the voltage in the capacitors. The simulation results show the bidirectional operation and the capacitor voltage balance of the converter under different operating conditions with high efficiency (98.2%).","PeriodicalId":69617,"journal":{"name":"电力电子","volume":"6 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89779396","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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