{"title":"A lossless active clamping circuit for current doubler topologies","authors":"Yan Zhu;Liang Yan;B. Lehman","doi":"10.1109/LPEL.2004.838776","DOIUrl":"https://doi.org/10.1109/LPEL.2004.838776","url":null,"abstract":"This letter presents a new lossless clamping circuit on the secondary side for DC-DC converters with a current-doubler structure. This circuit reduces ringing on secondary-side rectifiers due to leakage inductance. The ringing loss is recovered to the load. As a result, efficiency is improved, and the voltage stress on secondary-side rectifiers is reduced significantly. These improvements allow DC-DC topologies with a current doubler to operate efficiently at high switching frequencies. The operating principle of the clamping circuit is detailed. Simulations and experimental results validate the proposed technique.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"2 3","pages":"92-95"},"PeriodicalIF":0.0,"publicationDate":"2004-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2004.838776","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50225497","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}
Yang Zhang;R. Zane;A. Prodic;R. Erickson;D. Maksimovic
{"title":"Online calibration of MOSFET on-state resistance for precise current sensing","authors":"Yang Zhang;R. Zane;A. Prodic;R. Erickson;D. Maksimovic","doi":"10.1109/LPEL.2004.839635","DOIUrl":"https://doi.org/10.1109/LPEL.2004.839635","url":null,"abstract":"An approach for online current sensing calibration is presented where an auxiliary switch and a precision sense resistor are connected in parallel with a main power switch to achieve accuracy comparable to the sense resistor method, together with the advantage of essentially no additional power loss. The proposed current-sensing circuit and the calibration methods are particularly well suited for digital controller implementations where the required control and calibration functions can be easily accomplished. Experimental results with a digitally controlled 1.5-V 15-A synchronous buck converter demonstrate functionality of the online calibration approach, showing a significant improvement in accuracy over voltage sensing across the power MOSFET on-resistance.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"2 3","pages":"100-103"},"PeriodicalIF":0.0,"publicationDate":"2004-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2004.839635","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"50225503","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":"Digital phase control for resonant inverters","authors":"Y. Yin;R. Zane","doi":"10.1109/LPEL.2004.832032","DOIUrl":"https://doi.org/10.1109/LPEL.2004.832032","url":null,"abstract":"This letter presents an approach for direct digital phase control of resonant inverters that is based on inductor current or voltage sensing. Compared to frequency control, phase control provides the advantages of self-tuning to the tank resonant frequency, reduced sensitivity for improved control near resonance, and inherent protection against operation below resonance to avoid hard switching. The digital control algorithm suitable for implementation using standard CMOS logic is derived. The design details of an experimental test platform based on a Xilinx field programmable gate array (FPGA) and experimental results for a typical resonant inverter are provided.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"2 2","pages":"51-53"},"PeriodicalIF":0.0,"publicationDate":"2004-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2004.832032","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49984297","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":"Derivation of a second-order switching surface in the boundary control of buck converters","authors":"K.K.S. Leung;H.S.H. Chung","doi":"10.1109/LPEL.2004.834796","DOIUrl":"https://doi.org/10.1109/LPEL.2004.834796","url":null,"abstract":"A second-order switching surface in the boundary control of buck converters is derived in this letter. The formulated switching surface can make the overall converter exhibit better steady-state and transient behaviors than the one with a first-order switching surface. The switching surface is derived by estimating the state trajectory movement after a switching action, resulting in a high state trajectory velocity along the switching surface. This phenomenon accelerates the trajectory moving toward the target operating point. The proposed control scheme has been successfully applied to a 120-W buck converter. The large-signal performance and a comparison with the first-order switching surface have been studied.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"2 2","pages":"63-67"},"PeriodicalIF":0.0,"publicationDate":"2004-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2004.834796","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49984300","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":"Quality without compromise","authors":"","doi":"10.1109/LPEL.2004.835847","DOIUrl":"https://doi.org/10.1109/LPEL.2004.835847","url":null,"abstract":"Prospective authors are requested to submit new, unpublished manuscripts for inclusion in the upcoming event described in this call for papers.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"2 2","pages":"75-75"},"PeriodicalIF":0.0,"publicationDate":"2004-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2004.835847","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49984303","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 Letters publication information","authors":"","doi":"10.1109/LPEL.2004.835843","DOIUrl":"https://doi.org/10.1109/LPEL.2004.835843","url":null,"abstract":"Provides a listing of current society officers.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"2 2","pages":"c2-c2"},"PeriodicalIF":0.0,"publicationDate":"2004-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2004.835843","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49984294","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":"Digital correction of PWM switching amplifiers","authors":"P. Midya;B. Roeckner;S. Bergstedt","doi":"10.1109/LPEL.2004.834795","DOIUrl":"https://doi.org/10.1109/LPEL.2004.834795","url":null,"abstract":"Pulsewidth modulated (PWM) signals for driving a switching audio amplifier can be synthesized in the digital domain with extremely high linearity and precision. However, nonidealities associated with the power stage degrade output performance. A method to digitally correct for these nonidealities, resulting in very low total harmonic distortion (THD) and high signal-to-noise ratio (SNR) performance, is presented. This method also provides excellent rejection of power supply noise which is otherwise absent in digital PWM amplifiers. To meet noise requirements for hi-fi audio, the feedback structure is a fourth-order structure which shapes the noise beyond the audio band. The method has been implemented on a bread board, and state-of-the-art performance was achieved. Total harmonic distortion of 85 dB and dynamic range of 100 dB was measured using Audio Precision test equipment.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"2 2","pages":"68-72"},"PeriodicalIF":0.0,"publicationDate":"2004-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2004.834795","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49984301","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}
P. Cantillon-Murphy;T.C. Neugebauer;C. Brasca;D.J. Perreault
{"title":"An active ripple filtering technique for improving common-mode inductor performance","authors":"P. Cantillon-Murphy;T.C. Neugebauer;C. Brasca;D.J. Perreault","doi":"10.1109/LPEL.2004.831155","DOIUrl":"https://doi.org/10.1109/LPEL.2004.831155","url":null,"abstract":"Active ripple filtering is the replacement of large passive components in power filter circuits with smaller passive components and active control circuitry. This letter focuses on common-mode filters, where a large common-mode inductor (choke) is replaced by two smaller chokes and active op-amp control. The technique is appropriate when improved attenuation is required at relatively low frequencies and the high-frequency filtering requirements are easily met. Smaller chokes save significantly in material and winding costs. The technique is more advantageous if wire-wound chokes can be replaced by planar printed circuit board chokes. The use of the technique in an automotive electromagnetic interference (EMI) filter application is explored in detail.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"2 2","pages":"45-50"},"PeriodicalIF":0.0,"publicationDate":"2004-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2004.831155","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49984296","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":"A simple model for flux weakening in surface PM synchronous machines using back-to-back thyristors","authors":"A.M. EL-Refaie;D.W. Novotny;T.M. Jahns","doi":"10.1109/LPEL.2004.832635","DOIUrl":"https://doi.org/10.1109/LPEL.2004.832635","url":null,"abstract":"Flux weakening in surface permanent magnet (PM) synchronous machines is revisited in this letter. The condition for achieving infinite constant power speed ratio (CPSR) is explained from the machine equivalent circuit and phasor diagram point of view. Back-to-back thyristors, or triac, switches feeding the three phases of a surface PM synchronous machine will be shown to be equivalent to a simple series reactance with respect to fundamental component behavior. Using such switches is equivalent to adding a series inductance to the machine. This additional inductance helps extend the CPSR of surface PM synchronous machines. This is significant because extending the CPSR of surface PM machines is usually a challenging task due to the presence of low-permeability surface magnets and the resulting low machine inductance.","PeriodicalId":100635,"journal":{"name":"IEEE Power Electronics Letters","volume":"2 2","pages":"54-57"},"PeriodicalIF":0.0,"publicationDate":"2004-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/LPEL.2004.832635","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49984298","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}