The authors demonstrate a sequence of venting configurations and techniques, from an unmodified compact fluorescent downlight as a control fixture, through a series of venting strategies, to the development of a highly efficient downlight that incorporates a new angular concept in convective venting. With this new venting design, an increase in light output of nearly 25% can be attained without the optical losses generally associated with some venting geometries. The key issue in using convective venting as an effective thermal management technique is to maximize the thermal advantages of the venting configuration while reducing or eliminating the optical losses produced by openings in the envelop of the fixture or reflector. With the proper design and positioning of a convective venting geometry within a particular fixture, all of the benefits of a thermally efficient fixture can be obtained without compromise in optical efficiency.<>
{"title":"Variations in convective venting to increase the efficiency of compact fluorescent downlights","authors":"M. Siminovitch, C. Zhang, N. Kleinsmith","doi":"10.1109/IAS.1993.299186","DOIUrl":"https://doi.org/10.1109/IAS.1993.299186","url":null,"abstract":"The authors demonstrate a sequence of venting configurations and techniques, from an unmodified compact fluorescent downlight as a control fixture, through a series of venting strategies, to the development of a highly efficient downlight that incorporates a new angular concept in convective venting. With this new venting design, an increase in light output of nearly 25% can be attained without the optical losses generally associated with some venting geometries. The key issue in using convective venting as an effective thermal management technique is to maximize the thermal advantages of the venting configuration while reducing or eliminating the optical losses produced by openings in the envelop of the fixture or reflector. With the proper design and positioning of a convective venting geometry within a particular fixture, all of the benefits of a thermally efficient fixture can be obtained without compromise in optical efficiency.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127387182","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}
The authors present an analysis of the monopolar ionized field in conductor-to-plane configurations without resort to Deutsch's assumption. An iterative finite-element technique is used to solve Poisson's equation. Satisfying the current continuity condition and updating the space-charge density are based on the application of Kirchoff's current-balance law at each node of the finite-element grid, taking the ion diffusion into account. The proposed method of solution has been applied to laboratory and full-scale models of a monopolar transmission line. The calculated V-I characteristics and the current-density and electric field profiles at the ground plane agreed well with those measured experimentally in comparison with previous calculations. Fast convergence and simplicity in programming characterize the proposed method.<>
{"title":"Analysis of monopolar ionized field as influenced by ion diffusion","authors":"M. Abdel-Salam, Z. Al-Hamouz","doi":"10.1109/IAS.1993.299095","DOIUrl":"https://doi.org/10.1109/IAS.1993.299095","url":null,"abstract":"The authors present an analysis of the monopolar ionized field in conductor-to-plane configurations without resort to Deutsch's assumption. An iterative finite-element technique is used to solve Poisson's equation. Satisfying the current continuity condition and updating the space-charge density are based on the application of Kirchoff's current-balance law at each node of the finite-element grid, taking the ion diffusion into account. The proposed method of solution has been applied to laboratory and full-scale models of a monopolar transmission line. The calculated V-I characteristics and the current-density and electric field profiles at the ground plane agreed well with those measured experimentally in comparison with previous calculations. Fast convergence and simplicity in programming characterize the proposed method.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129133428","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}
A series of motor control experiments is described. The results are based on a nonlinear design technique called integrator backstepping. This model-based approach is applied to the design and implementation of high-performance trajectory tracking controllers for a BDC (brush DC) motor driving a single-link robot. Two controllers are proposed: an embedded computed torque controller which requires full-state feedback and an output feedback controller which only requires position measurement (i.e., observed backstepping). Both controllers require exact knowledge of the electromechanical dynamics in order to guarantee GES tracking performance. Extensions of the proposed backstepping techniques are discussed for more complex electromechanical systems, and for systems with uncertainty. The proposed controllers are simulated and implemented on a state-of-the-art DSP (digital signal processing) based workstation using a user-developed real-time DAC (data acquisition and control) system.<>
{"title":"Integrator backstepping techniques for the tracking control of permanent magnet brush DC motors","authors":"J. Carroll, M. Schneider, D. Dawson","doi":"10.1109/IAS.1993.298880","DOIUrl":"https://doi.org/10.1109/IAS.1993.298880","url":null,"abstract":"A series of motor control experiments is described. The results are based on a nonlinear design technique called integrator backstepping. This model-based approach is applied to the design and implementation of high-performance trajectory tracking controllers for a BDC (brush DC) motor driving a single-link robot. Two controllers are proposed: an embedded computed torque controller which requires full-state feedback and an output feedback controller which only requires position measurement (i.e., observed backstepping). Both controllers require exact knowledge of the electromechanical dynamics in order to guarantee GES tracking performance. Extensions of the proposed backstepping techniques are discussed for more complex electromechanical systems, and for systems with uncertainty. The proposed controllers are simulated and implemented on a state-of-the-art DSP (digital signal processing) based workstation using a user-developed real-time DAC (data acquisition and control) system.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133672792","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}
A sliding-mode control in electronic AC power supplies is presented. This control technique makes it possible to satisfy the increasing demand for the high-level performance of these systems, which include uninterruptible power supplies, test supplies, and fuel cell, and solar cell supplies. The existence and hitting conditions are discussed, and criteria for the selection of the control parameters which define the sliding surface and determine the quality of response are described. Improvements of the method are introduced to accommodate for the time-varying voltage reference and in the presence of an insulation transformer. A three-level, constant-frequency, variable-band dead-beat modulation technique is associated with the sliding control, producing ultrasonic, low-ripple modulation. Tests performed on an experimental prototype confirm the outstanding performance of the adopted control.<>
{"title":"An AC power supply with sliding-mode control","authors":"L. Malesani, L. Rossetto, A. Spiazzi, A. Zuccato","doi":"10.1109/IAS.1993.299037","DOIUrl":"https://doi.org/10.1109/IAS.1993.299037","url":null,"abstract":"A sliding-mode control in electronic AC power supplies is presented. This control technique makes it possible to satisfy the increasing demand for the high-level performance of these systems, which include uninterruptible power supplies, test supplies, and fuel cell, and solar cell supplies. The existence and hitting conditions are discussed, and criteria for the selection of the control parameters which define the sliding surface and determine the quality of response are described. Improvements of the method are introduced to accommodate for the time-varying voltage reference and in the presence of an insulation transformer. A three-level, constant-frequency, variable-band dead-beat modulation technique is associated with the sliding control, producing ultrasonic, low-ripple modulation. Tests performed on an experimental prototype confirm the outstanding performance of the adopted control.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"182 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116951136","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}
Formulation of the equations of motion for brushless motors in the compact form is considered. It is demonstrated that, by incorporating a combination of time scaling and linear state transformations, compact representations for the equations of motion can be obtained. It is shown that, by nondimensionalizing the equations of motion for brushless motors, one can significantly reduce the number of parameters in the model, and thus significantly reduce the complexity associated with the dynamic analysis procedure. Using the compact representations, it is demonstrated that the systems under investigation, subject to constant inputs and loads, possess multiple equilibrium states which characterize the global stability. As a by-product of the proposed scheme, an equivalence relationship between brushless motors and the Lorenz system is presented.<>
{"title":"Dynamic analysis of brushless motors based on compact representations of the equations of motion","authors":"N. Hemati","doi":"10.1109/IAS.1993.298903","DOIUrl":"https://doi.org/10.1109/IAS.1993.298903","url":null,"abstract":"Formulation of the equations of motion for brushless motors in the compact form is considered. It is demonstrated that, by incorporating a combination of time scaling and linear state transformations, compact representations for the equations of motion can be obtained. It is shown that, by nondimensionalizing the equations of motion for brushless motors, one can significantly reduce the number of parameters in the model, and thus significantly reduce the complexity associated with the dynamic analysis procedure. Using the compact representations, it is demonstrated that the systems under investigation, subject to constant inputs and loads, possess multiple equilibrium states which characterize the global stability. As a by-product of the proposed scheme, an equivalence relationship between brushless motors and the Lorenz system is presented.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"296 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131448558","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}
A self-adjusting diagnostic system for monitoring the frequency trimming process is described. The SAFUDS (self-adjusting fuzzy diagnostic system) is capable of adjusting its knowledge to the changes with two incorporated neural networks serving as a convenient online process monitoring system. The development of the SAFUDS not only fulfills the requirement of automating the diagnostics of the trimming process, but it also demonstrates the advantage of fuzzy logic over conventional logic in implementing the system. The use of fuzzy logic avoids the rigidity of conventional reasoning where it is difficult to process information that is definite or imprecise. One of the major advantages of the fuzzy monitoring strategy lies in the intelligibility and flexibility by which the process condition and control actions can be described directly from the experience and advice of an expert. With fuzzy logic, the system is able to heuristically interpret the condition of the process, like human operators. After the diagnostic system had been implemented for six months, the production yield rate of the frequency trimming process improved from 85% to 95%. During the implementation of the system, the knowledge of the production engineer as well as of the operators regarding the process improved.<>
{"title":"Self-adjusting diagnostic system for the manufacture of crystal resonators","authors":"B.H. Gwee, M. Lim, B.H. Soong","doi":"10.1109/IAS.1993.299139","DOIUrl":"https://doi.org/10.1109/IAS.1993.299139","url":null,"abstract":"A self-adjusting diagnostic system for monitoring the frequency trimming process is described. The SAFUDS (self-adjusting fuzzy diagnostic system) is capable of adjusting its knowledge to the changes with two incorporated neural networks serving as a convenient online process monitoring system. The development of the SAFUDS not only fulfills the requirement of automating the diagnostics of the trimming process, but it also demonstrates the advantage of fuzzy logic over conventional logic in implementing the system. The use of fuzzy logic avoids the rigidity of conventional reasoning where it is difficult to process information that is definite or imprecise. One of the major advantages of the fuzzy monitoring strategy lies in the intelligibility and flexibility by which the process condition and control actions can be described directly from the experience and advice of an expert. With fuzzy logic, the system is able to heuristically interpret the condition of the process, like human operators. After the diagnostic system had been implemented for six months, the production yield rate of the frequency trimming process improved from 85% to 95%. During the implementation of the system, the knowledge of the production engineer as well as of the operators regarding the process improved.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128460679","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}
An AC line fed switching power supply with a single power converter stage is described which operates with high input power factor while maintaining good regulation of the desired output DC voltage. The single-power converter is a dual active bridge DC-to-DC power converter (DABC), comprising high-frequency transformer-coupled input and output bridge converters. The DABC receives a rectified AC line voltage via a diode-bridge rectifier connected to a small, high-frequency filter capacitor. The two active bridges, generating edge-resonant square waves at their transformer terminals, appropriately phase-shifted from each other to simultaneously perform the high-efficiency DC output regulation while maintaining unity power factor at the AC input. The soft-switching nature of the converter allows increased performance (in terms of efficiency and stresses) and reduction in size/weight at operating frequencies in the range of 50-250 kHz. Simulations, and experimental results are presented to corroborate the analysis.<>
{"title":"Single phase unity power factor control for dual active bridge converter","authors":"M. Kheraluwala, R. W. D. Doncker","doi":"10.1109/IAS.1993.299007","DOIUrl":"https://doi.org/10.1109/IAS.1993.299007","url":null,"abstract":"An AC line fed switching power supply with a single power converter stage is described which operates with high input power factor while maintaining good regulation of the desired output DC voltage. The single-power converter is a dual active bridge DC-to-DC power converter (DABC), comprising high-frequency transformer-coupled input and output bridge converters. The DABC receives a rectified AC line voltage via a diode-bridge rectifier connected to a small, high-frequency filter capacitor. The two active bridges, generating edge-resonant square waves at their transformer terminals, appropriately phase-shifted from each other to simultaneously perform the high-efficiency DC output regulation while maintaining unity power factor at the AC input. The soft-switching nature of the converter allows increased performance (in terms of efficiency and stresses) and reduction in size/weight at operating frequencies in the range of 50-250 kHz. Simulations, and experimental results are presented to corroborate the analysis.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133513275","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}
A simple model for calculating the stator surface vibration of a unipolar four-phase hybrid stepping motor is presented. The approximate radial magnetic force per pole is calculated using a permeance model and its equivalent magnetic circuit. Based on the calculated radial magnetic forces and the measured stator mobility values, the radial vibration spectrum on top of a stator pole is estimated. The results show a reasonable agreement between the calculated and measured radial vibration levels. This verifies the analytical approach which, due to the special structure and excitation of the motor, is significantly different from the technique commonly employed for vibration study of induction machines.<>
{"title":"A simple model to calculate the stator radial vibration of a hybrid stepping motor","authors":"E. So, R.G.D. Williams, S.J. Yang","doi":"10.1109/IAS.1993.298913","DOIUrl":"https://doi.org/10.1109/IAS.1993.298913","url":null,"abstract":"A simple model for calculating the stator surface vibration of a unipolar four-phase hybrid stepping motor is presented. The approximate radial magnetic force per pole is calculated using a permeance model and its equivalent magnetic circuit. Based on the calculated radial magnetic forces and the measured stator mobility values, the radial vibration spectrum on top of a stator pole is estimated. The results show a reasonable agreement between the calculated and measured radial vibration levels. This verifies the analytical approach which, due to the special structure and excitation of the motor, is significantly different from the technique commonly employed for vibration study of induction machines.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122925601","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}
The utility of resonant inverter topologies in electronic ballasts for high-pressure sodium (HPS) lamps is examined. The three basic types of resonant inverters, series-loaded, parallel-loaded, and series-parallel-loaded, are compared for their applicability in electronic ballasts. A parallel-loaded resonant (PLR) inverter operating at a constant switching frequency is selected because of the high voltage gains possible. As a result, it is not necessary to use a transformer to provide enough voltage to start the HPS lamp from a low-voltage DC source such as that obtained from rectification of 120 V AC source. A PLR inverter was designed based on this analysis. A computer simulation of this design verified inverter operation when driving an HPS lamp. A laboratory prototype was then constructed and found to operate satisfactorily.<>
{"title":"A comparison of resonant inverter topologies for HPS lamp ballasts","authors":"R. Nelms, Tim D. Jones, M. C. Cosby","doi":"10.1109/IAS.1993.299200","DOIUrl":"https://doi.org/10.1109/IAS.1993.299200","url":null,"abstract":"The utility of resonant inverter topologies in electronic ballasts for high-pressure sodium (HPS) lamps is examined. The three basic types of resonant inverters, series-loaded, parallel-loaded, and series-parallel-loaded, are compared for their applicability in electronic ballasts. A parallel-loaded resonant (PLR) inverter operating at a constant switching frequency is selected because of the high voltage gains possible. As a result, it is not necessary to use a transformer to provide enough voltage to start the HPS lamp from a low-voltage DC source such as that obtained from rectification of 120 V AC source. A PLR inverter was designed based on this analysis. A computer simulation of this design verified inverter operation when driving an HPS lamp. A laboratory prototype was then constructed and found to operate satisfactorily.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123987233","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}
Various aspects of corona discharge treatment are reviewed. Particular attention is given to the Lissajous power measurement procedure; the significance of quartz, ceramic, or rubber as the dielectric in corona treaters; watt density considerations; and stabilizers and fatty acids.<>
{"title":"Corona discharge treatment","authors":"P. Sherman","doi":"10.1109/IAS.1993.299063","DOIUrl":"https://doi.org/10.1109/IAS.1993.299063","url":null,"abstract":"Various aspects of corona discharge treatment are reviewed. Particular attention is given to the Lissajous power measurement procedure; the significance of quartz, ceramic, or rubber as the dielectric in corona treaters; watt density considerations; and stabilizers and fatty acids.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124005955","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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