{"title":"Performance of a high-speed switched reluctance starter/generator system using electronic position sensing","authors":"S. R. Jones, B. Drager","doi":"10.1109/IAS.1995.530308","DOIUrl":"https://doi.org/10.1109/IAS.1995.530308","url":null,"abstract":"A switched reluctance machine-based system, whether a motor drive or a starter/generator, requires the rotor position to be determined to commutate at the correct instants. This paper compares the performance of a high-speed switched reluctance starter/generator (SR S/G) system when operating with a resolver to the performance when operating resolverless, or sensorless, using an electronic position sensing subsystem for rotor position estimation. A brief overview of the SR S/G system is given, followed by the approach for sensorless system operation. Test results are given, and system efficiency is compared, for both approaches when operating both as a starter and as a generator. Minimal difference is seen in system efficiency, with peaks at over 75 percent for start-mode and at over 79 percent for generate mode, for both resolver-based and sensorless operation.","PeriodicalId":117576,"journal":{"name":"IAS '95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132751026","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 new inverter control scheme for induction motor drives requiring wide speed range","authors":"M. Osama, T. Lipo","doi":"10.1109/IAS.1995.530321","DOIUrl":"https://doi.org/10.1109/IAS.1995.530321","url":null,"abstract":"A new control scheme to extend the speed range of four pole induction motor drives for electric vehicles is investigated. A three phase stator winding is used with each of the two coil groups per phase being independent resulting in a six coil, six terminal machine. Two inverters supply the machine with the required regulated currents to obtain the effect of either four pole or two pole windings. Four pole operation is proposed from zero speed until the end of its constant power region. Employing contactorless pole changing to obtain two pole operation extends the constant power region resulting in a doubling of the speed range for the same inverter/machine rating.","PeriodicalId":117576,"journal":{"name":"IAS '95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134147437","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 decentralized adaptive control algorithm and the application in power system stabilizer (PSS) design","authors":"J. Dai, A. Ghandakly","doi":"10.1109/IAS.1995.530501","DOIUrl":"https://doi.org/10.1109/IAS.1995.530501","url":null,"abstract":"This paper presents a new decentralized control algorithm, the generalized multivariable minimum variance (GMMV) control. The controller makes use of only local variables as feedback to generate control signals, and the external system dynamics are accounted for by a supplementary disturbance input term. The algorithm is combined with an online multivariable model identification method to form a self-tuning regulator (STR). As a practical application, a GMMV based power system stabilizer (PSS) is designed and tested by both computer simulation and on-line implementation. Results prove that the proposed new control algorithm and PSS are superior to the conventional and single variable based PSS schemes.","PeriodicalId":117576,"journal":{"name":"IAS '95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting","volume":"37 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115581937","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":"Modelling and simulation of run-out table cooling control using feedforward-feedback and element tracking system","authors":"R. Guo","doi":"10.1109/IAS.1995.530571","DOIUrl":"https://doi.org/10.1109/IAS.1995.530571","url":null,"abstract":"This article proposes a simple run-out table cooling control algorithm for an existing hot strip mill. The control system was designed to minimize the retrofit cost and to utilize existing equipment. Special consideration includes response times of top and bottom cooling headers, top header opening sequence, prediction of finisher speed, and strip element tracking. A six-dimensional look-up table was generated for feedforward control using an offline mathematical model which was identified and verified by rolling data. The feedforward loop was designed to obtain the target coiling temperature while the feedbackward loop was applied to attenuate cooling disturbance due to real-time changes of rolling parameters and prediction errors of the mathematical model.","PeriodicalId":117576,"journal":{"name":"IAS '95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114183494","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":"Formation of the charged droplet cloud and corona discharge between the cloud and a grounded electrode","authors":"T. Sugimoto, S. Tanaka, Y. Higashiyama, K. Asano","doi":"10.1109/IAS.1995.530438","DOIUrl":"https://doi.org/10.1109/IAS.1995.530438","url":null,"abstract":"The formation of a charged-droplet cloud with high charge density and the corona discharge characteristics between the cloud and a grounded electrode have been investigated. To form a charged-droplet cloud an electrostatic spray system with an airless nozzle is adopted. The spray system consists of an airless nozzle, a ring electrode and a blower. Since an airless nozzle can ejected large amount of droplets at once, a high density cloud can be created. Droplets in the cloud are electrified by means of induction phenomenon with the ring electrode. A blower is used to promote the transportation of the charged droplets and to grow in the charge density of the cloud. As the air-flow is faster, the charge amount of the ejected droplets and the charge density of the cloud increase. The air flow also influences the corona discharge from the grounded electrode to the charged cloud, extremely. The discharge current with air flow becomes several times larger than that without air flow, because the air flow prevents the deposition of charged droplets on the grounded electrode and no small corona discharge from the deposited droplets occurs. It suggests that the air flow is quite effective to make the discharge between a charged-droplet cloud and a grounded electrode.","PeriodicalId":117576,"journal":{"name":"IAS '95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114224181","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":"Direct torque control of permanent magnet drives","authors":"C. French, P. Acarnley","doi":"10.1109/IAS.1995.530302","DOIUrl":"https://doi.org/10.1109/IAS.1995.530302","url":null,"abstract":"Many permanent magnet motor drives use an open loop form of torque control, based on the assumption that output torque is proportional to applied current. In a practical motor this assumption may not always be correct, due to sub-optimal alignment of magnets, nonuniformity of magnetic material, current sensor nonlinearities and current controller limitations. These factors, together with nonoptimised current references, can lead to high values of torque ripple and copper loss. This paper describes a method of estimating the electromagnetic torque from the rate of change of co-energy with respect to position, thus taking account of mutual torque, reluctance torque and saturation effects. The paper shows how the estimator can be used in a direct torque control scheme. The direct torque controller maximises the torque/copper loss ratio. Implementation of the direct torque controller in a DSP based drive system is described, with steady-state and transient experimental results illustrating the effectiveness of the direct torque control scheme.","PeriodicalId":117576,"journal":{"name":"IAS '95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117098732","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":"Radial air gap force as a source of audible noise in a sinusoidally fed induction machine","authors":"V. Ostović, G. Boman","doi":"10.1109/IAS.1995.530353","DOIUrl":"https://doi.org/10.1109/IAS.1995.530353","url":null,"abstract":"A method for computation of the spatial and time harmonics of radial air gap force in an induction machine is presented in the paper. The method is applied to the analysis of radial air gap force generated at various modes of operation of an induction machine. The comparison of computed harmonics of force with measured noise spectrum shows a high degree of reliability of the proposed method in predicting the noise spectrum of an induction machine.","PeriodicalId":117576,"journal":{"name":"IAS '95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting","volume":"87 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116084060","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}
H. Boenig, J. Ferner, F. Bogdan, R. S. Rumrill, G. Morris
{"title":"Design and operation of a 40 MW, highly-stabilized power supply","authors":"H. Boenig, J. Ferner, F. Bogdan, R. S. Rumrill, G. Morris","doi":"10.1109/IAS.1995.530596","DOIUrl":"https://doi.org/10.1109/IAS.1995.530596","url":null,"abstract":"Four 10 MW, highly-stabilized power supply modules have been installed at the National High Magnetic Field Laboratory in Tallahassee, FL, to energize water-cooled, resistive, high-field research magnets. The power supply modules achieve a long term current stability of 10 ppm over a 12 h period with a short term ripple and noise variation of <10 ppm over a time period of one cycle. The power supply modules can operate independently, feeding four separate magnets, or two, three or four modules can operate in parallel. Each power supply module consists of a 12.5 kV vacuum circuit breaker, two three-winding, step-down transformers, a 24-pulse rectifier with interphase reactors, and a passive and an active filter. Two different transformer tap settings allow rated DC supply output voltages of 400 and 500 V. The rated current of a supply module is 17 kA and each supply module has a one-hour overload capability of 20 kA. The isolated output terminals of each power supply module are connected to a reversing switch. An extensive high-current bus system allows the modules to be connected to 16 magnet cells. This paper presents the detailed design of the power supply components. Various test results taken during the commissioning phase with a 10 MW resistive load and results taken with the research magnets are shown. The effects of the modules on the electrical supply system and the operational behavior of the power factor correction/harmonic filters are described. Also included are results of a power supply module feeding a superconducting magnet during quench propagation tests.","PeriodicalId":117576,"journal":{"name":"IAS '95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting","volume":"157 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115274409","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":"Partial electrostatic discharge induced by precharged dielectric surfaces","authors":"T.S. Lee, J. Gasal","doi":"10.1109/IAS.1995.530485","DOIUrl":"https://doi.org/10.1109/IAS.1995.530485","url":null,"abstract":"When a blunt-nosed earthed object approaches a dielectric surface bearing strong levels of precharging, a micro-spark ensues within sub-mm distance. When the same object is sharp-nosed, on the other hand, a different mode has been found to apply: in place of sparking, tip corona leading to slow surface-wide neutralization would begin at a separation on the order of multiple cms. This work studies the phenomenon in selective experiments using dielectric surfaces precharged by both polarities with corona onset triggered at finite potentials. Current waveforms indicate inverse RF pulsing, which shares some common features with the familiar Trichel pulsing. Also noted is the phenomenon of pulse-bunching near onset condition of inverse corona, in which groups of such pulses, typically a few in each, would occur in quick but irregular succession.","PeriodicalId":117576,"journal":{"name":"IAS '95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115496063","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":"Switching harmonics in the DC link current in a PWM AC-DC-AC converter","authors":"H. Zhang, N. Wheeler, D. Grant","doi":"10.1109/IAS.1995.530640","DOIUrl":"https://doi.org/10.1109/IAS.1995.530640","url":null,"abstract":"A novel method for determining the DC link current drawn by a PWM inverter is described. The equations derived are simple to apply and yield considerable analytical insight into the DC link current waveform. The method enables the RMS current flowing in the DC link capacitor in a back-to-back power converter to be calculated, allowing the capacitor to be specified correctly. Simulated and experimental results verify the analysis.","PeriodicalId":117576,"journal":{"name":"IAS '95. Conference Record of the 1995 IEEE Industry Applications Conference Thirtieth IAS Annual Meeting","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1995-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123364788","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}