{"title":"Low-harmonic, three-phase rectifier that applies current injection and a passive resistance emulator","authors":"P. Pejovic;P. Bozovic;D. Shmilovitz","doi":"10.1109/LPEL.2005.858411","DOIUrl":"https://doi.org/10.1109/LPEL.2005.858411","url":null,"abstract":"A new three-phase diode bridge rectifier that provides low harmonic distortion of the input currents applying current injection technique is proposed in this paper. The rectifier applies a novel passive resistance emulator consisting of four diodes and a transformer with the volt-ampere rating of 3.57% of the rectifier-rated power. Optimization of the transformer turns ratio is performed in order to minimize the input current total harmonic distortion (THD). It is shown that with the optimal turns ratio the input current THD equals 3.72%. Dependence of the input current THD on the load current is analyzed, and it is shown that at low load currents the rectifier operates in the discontinuous conduction mode with the THD of 7.79%. The analytical results are experimentally verified on a 2 kW rectifier, indicating that the input current THD lower than 8% is provided within a wide range of the load current variations applying simple circuitry.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"3 3","pages":"96-100"},"PeriodicalIF":0.0,"publicationDate":"2005-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2005.858411","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50326670","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}
{"title":"Improvement of light-load efficiency using width-switching scheme for CMOS transistors","authors":"S. Musunuri;P.L. Chapman","doi":"10.1109/LPEL.2005.859769","DOIUrl":"https://doi.org/10.1109/LPEL.2005.859769","url":null,"abstract":"This paper presents a derivation of the optimum width of transistors to minimize losses in monolithic CMOS buck converters. The high optimal width requires a tapered inverter chain gate driver. A technique called \"width switching\" is presented. It can be integrated with the inverter chain to maintain maximum converter efficiency over a wide power range, particularly at light load. Experimental results are presented from a chip containing CMOS transistors optimized for power levels between 50 mW and 200 mW. Challenges in implementing the width-switching scheme and other applications are also discussed.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"3 3","pages":"105-110"},"PeriodicalIF":0.0,"publicationDate":"2005-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2005.859769","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50325582","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}
{"title":"Flux-based two-degrees-of-freedom algorithm for three-phase electronic converter control","authors":"Poh Chiang Loh;Gary Hun Hiong Pang","doi":"10.1109/LPEL.2005.855479","DOIUrl":"https://doi.org/10.1109/LPEL.2005.855479","url":null,"abstract":"This letter integrates the tracking robustness of two-degrees-of-freedom control and fast dynamic response of flux-based, pulse-width modulation to develop a new current controller for high performance, three-phase electronic converter control. Theoretical analysis shows that the controller can simultaneously achieve good steady-state, transient and harmonic performance, which are challenges not previously met by existing current controllers reported in the literature. Experimental results are presented to verify the performance and practicality of the proposed controller.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"3 3","pages":"89-91"},"PeriodicalIF":0.0,"publicationDate":"2005-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2005.855479","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50325585","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}
{"title":"Commutation technique for high-frequency link cycloconverter based on state-Machine control","authors":"R.S. Balog;P.T. Krein","doi":"10.1109/LPEL.2005.858422","DOIUrl":"https://doi.org/10.1109/LPEL.2005.858422","url":null,"abstract":"A technique for commutating the load current of a high-frequency link, pulse-width modulated cycloconverter is presented. As the load current makes a sign transition, switch operation becomes critical to avoid commutation failure. Previous techniques required either dead time or the use of large inductors to limit shoot-through current, thereby compromising performance and efficiency. The technique presented here identifies the switching sequence that is necessary to allow load current to commutate naturally without distortion. The switching sequence is managed with a state machine.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"3 3","pages":"101-104"},"PeriodicalIF":0.0,"publicationDate":"2005-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2005.858422","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50326669","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}
Ning-Yi Dai;Man-Chung Wong;Yuan-Hua Chen;Ying-Duo Han
{"title":"A 3-D generalized direct PWM algorithm for multilevel converters","authors":"Ning-Yi Dai;Man-Chung Wong;Yuan-Hua Chen;Ying-Duo Han","doi":"10.1109/LPEL.2005.855112","DOIUrl":"https://doi.org/10.1109/LPEL.2005.855112","url":null,"abstract":"A three-dimensional (3-D) generalized direct pulse width modulation (PWM) algorithm is proposed for multilevel converters in a three-phase, four-wire system. It is proved to be equivalent to the newly proposed generalized 3-D space vector modulation (SVM). However, the direct PWM greatly simplifies the calculation process and is much easier to implement in digital controllers. The direct PWM can be used in all applications needing a 3-D control vector, such as active filters, uninterruptible power supplies, etc. Simulation and experimental results are given to show the validity of the proposed control strategy.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"3 3","pages":"85-88"},"PeriodicalIF":0.0,"publicationDate":"2005-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2005.855112","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50325586","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}
{"title":"IEEE Power Electronics Society Information","authors":"","doi":"10.1109/LPEL.2005.860647","DOIUrl":"https://doi.org/10.1109/LPEL.2005.860647","url":null,"abstract":"Provides a listing of current society officers.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"3 3","pages":"c3-c3"},"PeriodicalIF":0.0,"publicationDate":"2005-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2005.860647","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50326666","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}
{"title":"Harmonic optimization of multilevel converters using genetic algorithms","authors":"B. Ozpineci;L.M. Tolbert;J.N. Chiasson","doi":"10.1109/LPEL.2005.856713","DOIUrl":"https://doi.org/10.1109/LPEL.2005.856713","url":null,"abstract":"In this letter, a genetic algorithm (GA) optimization technique is applied to determine the switching angles for a cascaded multilevel inverter which eliminates specified higher order harmonics while maintaining the required fundamental voltage. This technique can be applied to multilevel inverters with any number of levels. As an example, in this paper a seven-level inverter is considered, and the optimum switching angles are calculated offline to eliminate the fifth and seventh harmonics. These angles are then used in an experimental setup to validate the results.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"3 3","pages":"92-95"},"PeriodicalIF":0.0,"publicationDate":"2005-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2005.856713","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50326668","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}
{"title":"Frequency domain model of conducted EMI in electrical drives","authors":"E. Gubia;P. Sanchis;A. Ursua;J. Lopez;L. Marroyo","doi":"10.1109/LPEL.2005.848730","DOIUrl":"https://doi.org/10.1109/LPEL.2005.848730","url":null,"abstract":"A harmful aspect of adjustable speed drives is the presence of large high-frequency stray currents. The most important, from the view of electromagnetic compatibility, are common-mode currents at the output and input sides of the converter. Currents at the output flow through the installation ground while those at the input flow through the grid ground. These common-mode currents can cause disturbances in other units that are connected within the same power section or placed close to the drive. This paper proposes a simulation model for a complete drive system based on the frequency domain. The model accurately reproduces the behavior of common-mode currents at any point of the system and allows the user to understand the influence of each system element on the currents. Thus, the model is useful both for designing filter structures and placing them at the proper position inside the adjustable speed drive. The model is validated by means of experimental results on a 5 kVA adjustable speed drive.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"3 2","pages":"45-49"},"PeriodicalIF":0.0,"publicationDate":"2005-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2005.848730","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50328376","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}
{"title":"Electronic controlled device for the analysis and design of photovoltaic systems","authors":"P. Sanchis;J. Lopez;A. Ursua;L. Marroyo","doi":"10.1109/LPEL.2005.851314","DOIUrl":"https://doi.org/10.1109/LPEL.2005.851314","url":null,"abstract":"The characterization and design of photovoltaic systems is a difficult issue due to the variable operation atmospheric conditions. With this aim, simulators and measurement equipments have been proposed. However, most of them do not deal with real atmospheric conditions. This letter proposes an electronic device that first measures the real evolution of the I-V characteristic curves of photovoltaic modules and generators, and then physically emulates in real time these curves to test photovoltaic inverters. The device consists of a dc-dc converter, a microcontroller and a data storage unit. The two operation modes (emulation and measurement) are digitally driven by the microcontroller. The converter current is controlled by means of a variable-hysteresis control loop, whose reference is provided by the microcontroller. In addition, a digital voltage control loop is designed to find out the complete characteristic curves of the photovoltaic generators. A 15-kW prototype is designed and built that can measure three times per second the characteristic curves of up to seven generators and then emulate their electrical behavior to test photovoltaic inverters. With the proposed device, the optimal configuration and performance of photovoltaic modules and generators, as well as the operation of photovoltaic inverters can be thoroughly analyzed under real atmospheric conditions.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"3 2","pages":"57-62"},"PeriodicalIF":0.0,"publicationDate":"2005-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2005.851314","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50328379","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}
{"title":"Correction to \"A Nonlinearity Compensation Method for a Matrix Converter Drive\"","authors":"K.-B. Lee;F. Blaabjerg","doi":"10.1109/LPEL.2005.847409","DOIUrl":"https://doi.org/10.1109/LPEL.2005.847409","url":null,"abstract":"This paper presents a new method to compensate the nonlinearities for matrix converter drives. The nonlinearities of matrix converter drives such as commutation delay, turn-on and turn-off time of the switching devices, and on-state switching device voltage drop is corrected by a new matrix converter model using the direction of current. The proposed method does not need any additional hardware or complicated software and it is easy to realize by applying the algorithm to the conventional vector control. The proposed compensation method is applied for high-performance induction motor drives using a 3-kW matrix converter system without a speed sensor. Experimental results show the proposed method provides good compensating characteristics.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"3 2","pages":"81-81"},"PeriodicalIF":0.0,"publicationDate":"2005-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2005.847409","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50328384","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}