The impact of accurate, three-winding transformer models in the analysis of mine power systems is examined. Though the disparity in voltage regulation is minimal, the enhanced representation of three-winding transformers seriously affects the results of both steady-state and first-cycle fault analysis. Fault current magnitudes could be underestimated by as much as 60% at strategic locations in the mine power system. This directly affects the choice and sizing of protective and coordination devices used in mine power systems. The effect of winding temperature is also important, but the values do not vary too much from values computed for correctly represented, four-bus, three winding transformer models.<>
{"title":"Effect of three-winding transformer models on the analysis and protection of mine power systems","authors":"M. Oommen, J. Kohler","doi":"10.1109/IAS.1993.299221","DOIUrl":"https://doi.org/10.1109/IAS.1993.299221","url":null,"abstract":"The impact of accurate, three-winding transformer models in the analysis of mine power systems is examined. Though the disparity in voltage regulation is minimal, the enhanced representation of three-winding transformers seriously affects the results of both steady-state and first-cycle fault analysis. Fault current magnitudes could be underestimated by as much as 60% at strategic locations in the mine power system. This directly affects the choice and sizing of protective and coordination devices used in mine power systems. The effect of winding temperature is also important, but the values do not vary too much from values computed for correctly represented, four-bus, three winding transformer models.<<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":"124398852","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 experimental investigation of transient charge decay in a vessel partially filled with electrically charged liquid is reported. The test facility is an upright cylindrical tank with diameter and height equal to 50 cm. It is instrumented to permit continuous measurement of both the bulk charge density in the liquid and the electrostatic field during experimental runs. By correlating the time course of the bulk charge density to that of the electrostatic field, the transient redistribution of electrostatic charge can be characterized. One objective of this research is to ascertain the role played by surface charge in controlling the transient decay.<>
{"title":"Observation of transient charge relaxation of oil within a cylindrical vessel","authors":"Y. Matsubara, T. Jones","doi":"10.1109/IAS.1993.299069","DOIUrl":"https://doi.org/10.1109/IAS.1993.299069","url":null,"abstract":"An experimental investigation of transient charge decay in a vessel partially filled with electrically charged liquid is reported. The test facility is an upright cylindrical tank with diameter and height equal to 50 cm. It is instrumented to permit continuous measurement of both the bulk charge density in the liquid and the electrostatic field during experimental runs. By correlating the time course of the bulk charge density to that of the electrostatic field, the transient redistribution of electrostatic charge can be characterized. One objective of this research is to ascertain the role played by surface charge in controlling the transient decay.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"25 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":"121387160","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 investigated the decomposition performance of gaseous environmental destructive contaminants in air by using atmospheric-pressure discharge plasma including SPCP (surface discharge induced plasma chemical processing). Contaminants tested were chlorofluorocarbon (CFC-113) and trichloroethylene. The discharge exciting frequency range was wide, from 50 Hz to 50 kHz. Low-frequency discharge requires high voltage to inject high electric power into the gas and to decompose contaminants. A gaschromato mass spectrometer analyzed discharge products of dense CFC-113 or trichloroethylene, and HCl, CClFO, CHCl, etc. were detected as products. Two different electrode configurations, silent discharge (coaxial) electrode and coil electrode, were tested and compared.<>
{"title":"Atmospheric pressure discharge plasma processing for gaseous air contaminants","authors":"T. Oda, R. Yamashita, T. Takahashi, S. Masuda","doi":"10.1109/IAS.1993.299132","DOIUrl":"https://doi.org/10.1109/IAS.1993.299132","url":null,"abstract":"The authors investigated the decomposition performance of gaseous environmental destructive contaminants in air by using atmospheric-pressure discharge plasma including SPCP (surface discharge induced plasma chemical processing). Contaminants tested were chlorofluorocarbon (CFC-113) and trichloroethylene. The discharge exciting frequency range was wide, from 50 Hz to 50 kHz. Low-frequency discharge requires high voltage to inject high electric power into the gas and to decompose contaminants. A gaschromato mass spectrometer analyzed discharge products of dense CFC-113 or trichloroethylene, and HCl, CClFO, CHCl, etc. were detected as products. Two different electrode configurations, silent discharge (coaxial) electrode and coil electrode, were tested and compared.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"12 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":"114518204","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 step-by-step approach to identifying the parameters of an induction machine from standstill time-domain test data is presented. A step voltage disturbance is applied across the stator terminals while the machine is in standstill condition, and the resulting stator voltage and current responses are measured. The initialization of the transfer function model parameters is achieved by the Laplace transformation of the recorded time-response data, and the maximum likelihood method is used for both the transfer function and the equivalent circuit model parameter estimation. Based on the identified models, simulation studies are performed and compared to the measured standstill time-domain response, the standstill frequency response, and the free acceleration response to validate the identified models. A three-phase wound rotor induction machine rated at 5 hp and 220 V was tested at standstill, and its parameters were estimated.<>
{"title":"Estimation of induction machine parameters from standstill time domain data","authors":"S. Moon, A. Keyhani","doi":"10.1109/IAS.1993.298945","DOIUrl":"https://doi.org/10.1109/IAS.1993.298945","url":null,"abstract":"A step-by-step approach to identifying the parameters of an induction machine from standstill time-domain test data is presented. A step voltage disturbance is applied across the stator terminals while the machine is in standstill condition, and the resulting stator voltage and current responses are measured. The initialization of the transfer function model parameters is achieved by the Laplace transformation of the recorded time-response data, and the maximum likelihood method is used for both the transfer function and the equivalent circuit model parameter estimation. Based on the identified models, simulation studies are performed and compared to the measured standstill time-domain response, the standstill frequency response, and the free acceleration response to validate the identified models. A three-phase wound rotor induction machine rated at 5 hp and 220 V was tested at standstill, and its parameters were estimated.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"41 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":"115478081","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 continuous-time parametrically optimized adaptive self-tuning regulator (POSTR) is proposed for the design of power system stabilizers. This POSTR consists of an identification scheme which identifies the nonlinear power system with a predictive model and a control technique based on parameter optimization to derive the control law. The control design consists of choosing a suitable regulator structure and then tuning the associated parameters. The proposed stabilizer design technique has flexibility in specifying the order and the structure of the regulator, which offers advantages in selecting and autotuning well-known effective controller structures. Simulation study results are presented which show that the proposed technique outperforms the fixed parameter conventional stabilizer and the adaptive minimum variance self-tuner.<>
{"title":"Adaptive enhancement of synchronous generator stabilizer performance using a parameter optimization technique","authors":"A. M. Farhoud, A. Jalal, A. Ghandakly","doi":"10.1109/IAS.1993.298917","DOIUrl":"https://doi.org/10.1109/IAS.1993.298917","url":null,"abstract":"A continuous-time parametrically optimized adaptive self-tuning regulator (POSTR) is proposed for the design of power system stabilizers. This POSTR consists of an identification scheme which identifies the nonlinear power system with a predictive model and a control technique based on parameter optimization to derive the control law. The control design consists of choosing a suitable regulator structure and then tuning the associated parameters. The proposed stabilizer design technique has flexibility in specifying the order and the structure of the regulator, which offers advantages in selecting and autotuning well-known effective controller structures. Simulation study results are presented which show that the proposed technique outperforms the fixed parameter conventional stabilizer and the adaptive minimum variance self-tuner.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"34 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":"126878578","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}
One-step-ahead adaptive control with an input nonlinearity strategy is proposed to control the converted system of a traditional milling machine table with a lead screw transmission system. The control plant is a traditional lead screw actuated milling machine table which has been retrofitted with DC servomotor control. This old-fashioned machining table has nonlinear time-varying behavior due to the effects of irregular Coulomb friction of sliding surface and obvious backlash. Experimental results show that the control method has reasonable performance in terms of stability, transient response, tracking, and robustness under the influence of time delay of the simple motor driver and 1 mm backlash of each axis. This controller can overcome the nonlinear effect due to Coulomb friction and construct a stable closed-loop system.<>
{"title":"The adaptive control for retrofit traditional milling machine","authors":"S. Huang, M. Yan","doi":"10.1109/IAS.1993.299155","DOIUrl":"https://doi.org/10.1109/IAS.1993.299155","url":null,"abstract":"One-step-ahead adaptive control with an input nonlinearity strategy is proposed to control the converted system of a traditional milling machine table with a lead screw transmission system. The control plant is a traditional lead screw actuated milling machine table which has been retrofitted with DC servomotor control. This old-fashioned machining table has nonlinear time-varying behavior due to the effects of irregular Coulomb friction of sliding surface and obvious backlash. Experimental results show that the control method has reasonable performance in terms of stability, transient response, tracking, and robustness under the influence of time delay of the simple motor driver and 1 mm backlash of each axis. This controller can overcome the nonlinear effect due to Coulomb friction and construct a stable closed-loop system.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"29 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":"126887187","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 microscopic model for an electrostatic spraying system is presented to investigate the effect of the voltage applied to the induction nozzle on the droplet's charge, mobility, and charge-to-mass ratio. The variation of these parameters along the jet was also studied. The model also lays particular emphasis on the effect of the applied voltage on the spray current and the charge density at the nozzle. A macroscopic model for the electrostatic spraying system is also presented. The objective of this model is to study the spatial distribution of the droplet charge density, transit time, and trajectory in the region between the nozzle and the target in terms of the flow velocity of the spray and the space-charge-produced electric field. On the macroscopic scale, both the droplet charge density and the spray current increase with the voltage applied to the charging electrode. With the decrease of the spray flow velocity, the space-charge produced electric field becomes dominant. On the microscopic scale, induction charging eliminates the ion current from the current to the target and the associated back-ionization.<>
{"title":"Microscopic and macroscopic modeling of electrostatic-based pesticide spray systems","authors":"M. S. Abdel-Salam, F. Soliman, A. Megahed","doi":"10.1109/IAS.1993.299119","DOIUrl":"https://doi.org/10.1109/IAS.1993.299119","url":null,"abstract":"A microscopic model for an electrostatic spraying system is presented to investigate the effect of the voltage applied to the induction nozzle on the droplet's charge, mobility, and charge-to-mass ratio. The variation of these parameters along the jet was also studied. The model also lays particular emphasis on the effect of the applied voltage on the spray current and the charge density at the nozzle. A macroscopic model for the electrostatic spraying system is also presented. The objective of this model is to study the spatial distribution of the droplet charge density, transit time, and trajectory in the region between the nozzle and the target in terms of the flow velocity of the spray and the space-charge-produced electric field. On the macroscopic scale, both the droplet charge density and the spray current increase with the voltage applied to the charging electrode. With the decrease of the spray flow velocity, the space-charge produced electric field becomes dominant. On the microscopic scale, induction charging eliminates the ion current from the current to the target and the associated back-ionization.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"7 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":"127939080","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}
It is demonstrated that artificial neural networks can be used to identify and compensate for hysteresis caused by gear backlash in precision position-controlled mechanisms. Physical analysis of the system nonlinearities and optimal control are used to design the neural network structure. Network sizing and initializing problems are thus eliminated. This physically meaningful, modular approach facilitates the integration of this neural network with existing controllers; thus, initial performance matches that of existing control approaches and then is improved by refining the parameter estimates via further learning. The neural network operates by recognizing backlash and switching to a control which moves smoothly through the backlash when a torque transmitted to the output shaft must be reversed.<>
{"title":"Neural network compensation of gear backlash hysteresis in position-controlled mechanisms","authors":"D.R. Seidl, S. Lam, J. A. Putnam, R. Lorenz","doi":"10.1109/IAS.1993.299141","DOIUrl":"https://doi.org/10.1109/IAS.1993.299141","url":null,"abstract":"It is demonstrated that artificial neural networks can be used to identify and compensate for hysteresis caused by gear backlash in precision position-controlled mechanisms. Physical analysis of the system nonlinearities and optimal control are used to design the neural network structure. Network sizing and initializing problems are thus eliminated. This physically meaningful, modular approach facilitates the integration of this neural network with existing controllers; thus, initial performance matches that of existing control approaches and then is improved by refining the parameter estimates via further learning. The neural network operates by recognizing backlash and switching to a control which moves smoothly through the backlash when a torque transmitted to the output shaft must be reversed.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"42 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":"126702284","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 current-controlled current-source-type unity power factor PWM (pulse-width-modulated) rectifier is proposed. The three input line currents are controlled independently to obtain sinusoidal currents with low oscillations during transients. Power factor is controlled directly, and unity power factor operation can readily be achieved. Output DC voltage is regulated by varying the amplitude of the AC input current references. The proposed rectifier exhibits excellent steady-state operation and good transient dynamics, a result of the current control method used. A complete analysis of the PWM rectifier and control circuitry is given, and design guidelines are discussed. The theoretical results and design equations are verified by simulation and experiments on a 1.5 kVA prototype unit.<>
{"title":"A current-controlled current source type unity power factor PWM rectifier","authors":"N. Zargari, G. Joós","doi":"10.1109/IAS.1993.298989","DOIUrl":"https://doi.org/10.1109/IAS.1993.298989","url":null,"abstract":"A current-controlled current-source-type unity power factor PWM (pulse-width-modulated) rectifier is proposed. The three input line currents are controlled independently to obtain sinusoidal currents with low oscillations during transients. Power factor is controlled directly, and unity power factor operation can readily be achieved. Output DC voltage is regulated by varying the amplitude of the AC input current references. The proposed rectifier exhibits excellent steady-state operation and good transient dynamics, a result of the current control method used. A complete analysis of the PWM rectifier and control circuitry is given, and design guidelines are discussed. The theoretical results and design equations are verified by simulation and experiments on a 1.5 kVA prototype unit.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"61 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":"126397321","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 micro-vortex was observed to occur in liquid films exposed to the combined action of a focused laser beam and a high-frequency electric field. The laser beam was perpendicular to both the surface of the liquid film and the direction of the electric field. The size of this optoelectrostatical microvortex (OEMV) in various liquids (water, ethanol, acetone, nitrobenzene) varied with the conditions of the experiment, but stayed in the 10 mu m range. The velocity of the liquid flow in the vortex could be controlled according to the intensity and frequency of the electric field (5*10/sup 4/ to 10/sup 6/ V/m, 2*10/sup 4/ to 10/sup 6/ Hz), laser power (0 to 2 W), and laser power density in the focal point. No microvortex was observed in benzene and chloroform. As an application of this phenomenon, single DNA molecules could be transported along the OEMV.<>
{"title":"Liquid micro-vortex generated around laser focal point in an intense high-frequency electric field","authors":"A. Mizuno, M. Nishioka, V. Ohno, L. Dascelescu","doi":"10.1109/IAS.1993.299084","DOIUrl":"https://doi.org/10.1109/IAS.1993.299084","url":null,"abstract":"A micro-vortex was observed to occur in liquid films exposed to the combined action of a focused laser beam and a high-frequency electric field. The laser beam was perpendicular to both the surface of the liquid film and the direction of the electric field. The size of this optoelectrostatical microvortex (OEMV) in various liquids (water, ethanol, acetone, nitrobenzene) varied with the conditions of the experiment, but stayed in the 10 mu m range. The velocity of the liquid flow in the vortex could be controlled according to the intensity and frequency of the electric field (5*10/sup 4/ to 10/sup 6/ V/m, 2*10/sup 4/ to 10/sup 6/ Hz), laser power (0 to 2 W), and laser power density in the focal point. No microvortex was observed in benzene and chloroform. As an application of this phenomenon, single DNA molecules could be transported along the OEMV.<<ETX>>","PeriodicalId":345027,"journal":{"name":"Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting","volume":"21 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":"124300054","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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