Pub Date : 1989-05-23DOI: 10.1109/NSEMC.1989.37190
J. Suriano, C. Ong
Electromechanical and electromagnetic disturbances produced by DC motors were modeled using a dynamic electrical network representation that includes a representation of the changing circuit configuration due to the commutation. With this technique the instantaneous current and voltage of each of the armature coils of the motor are computed as is the instantaneous electromagnetic torque developed by the motor. This tensor-based network model generates inputs to a set of state equations describing the electromagnetic and electromechanical behavior of the motor. The output can be used to study sources of noise and vibration in addition to performance characteristics for DC motors. Using this model, the effects of manufacturing tolerances in the assembly of motors can be evaluated. The tensor-based method is used to simulate time-varying circuit topology of the armature winding of a DC motor. Some numerical results comparing the predicted with the measured waveforms of a sample three-brush DC motor are discussed.<>
{"title":"Modeling of electromechanical and electromagnetic disturbances in DC motors","authors":"J. Suriano, C. Ong","doi":"10.1109/NSEMC.1989.37190","DOIUrl":"https://doi.org/10.1109/NSEMC.1989.37190","url":null,"abstract":"Electromechanical and electromagnetic disturbances produced by DC motors were modeled using a dynamic electrical network representation that includes a representation of the changing circuit configuration due to the commutation. With this technique the instantaneous current and voltage of each of the armature coils of the motor are computed as is the instantaneous electromagnetic torque developed by the motor. This tensor-based network model generates inputs to a set of state equations describing the electromagnetic and electromechanical behavior of the motor. The output can be used to study sources of noise and vibration in addition to performance characteristics for DC motors. Using this model, the effects of manufacturing tolerances in the assembly of motors can be evaluated. The tensor-based method is used to simulate time-varying circuit topology of the armature winding of a DC motor. Some numerical results comparing the predicted with the measured waveforms of a sample three-brush DC motor are discussed.<<ETX>>","PeriodicalId":408694,"journal":{"name":"National Symposium on Electromagnetic Compatibility","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115448600","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}
Pub Date : 1989-05-23DOI: 10.1109/NSEMC.1989.37168
R. Garver, J. Tatum
The concept of radio frequency interference (RFI) is expanded to include RF damage or radiofrequency effects (RFEs). An assessment methodology was developed to predict the RF power density incident on a system that would cause upset or damage to the system electronics. This RFE assessment methodology is based on a modified version of the methodology used for electromagnetic pulse assessments. In the general assessment methodology for a system with a single entry path and critical component, the system under investigation is surveyed to identify the critical components and candidate RF entry ports. These areas are characterized in detail. The external power density that defines the susceptibility threshold of the system is determined. The methodology presents the results as a probability of system upset or damage (failure probability) as a function of incident RF power density.<>
{"title":"Assessment methodology for radio frequency effects (RFE)","authors":"R. Garver, J. Tatum","doi":"10.1109/NSEMC.1989.37168","DOIUrl":"https://doi.org/10.1109/NSEMC.1989.37168","url":null,"abstract":"The concept of radio frequency interference (RFI) is expanded to include RF damage or radiofrequency effects (RFEs). An assessment methodology was developed to predict the RF power density incident on a system that would cause upset or damage to the system electronics. This RFE assessment methodology is based on a modified version of the methodology used for electromagnetic pulse assessments. In the general assessment methodology for a system with a single entry path and critical component, the system under investigation is surveyed to identify the critical components and candidate RF entry ports. These areas are characterized in detail. The external power density that defines the susceptibility threshold of the system is determined. The methodology presents the results as a probability of system upset or damage (failure probability) as a function of incident RF power density.<<ETX>>","PeriodicalId":408694,"journal":{"name":"National Symposium on Electromagnetic Compatibility","volume":"35 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113980380","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}
Pub Date : 1989-05-23DOI: 10.1109/NSEMC.1989.37148
J. Walther
Commercial sources of conductive silicone gaskets for electromagnetic interference (EMI) shielding filled with silver-plated glass microspheres were highly stable under conditions of severe vibration and intense simulated electromagnetic pulse (EMP). The results are in contrast to data published by C.H. Kuist (1977) and may demonstrate a considerable advancement in EMI gasket and conductive filler manufacturing technologies. The data showed there is no longer reason for concern over vibration and EMP stabilities of silver-glass gaskets.<>
{"title":"Electrical stability during vibration and electromagnetic pulse survivability of silver-plated glass bead filled EMI shielding gaskets","authors":"J. Walther","doi":"10.1109/NSEMC.1989.37148","DOIUrl":"https://doi.org/10.1109/NSEMC.1989.37148","url":null,"abstract":"Commercial sources of conductive silicone gaskets for electromagnetic interference (EMI) shielding filled with silver-plated glass microspheres were highly stable under conditions of severe vibration and intense simulated electromagnetic pulse (EMP). The results are in contrast to data published by C.H. Kuist (1977) and may demonstrate a considerable advancement in EMI gasket and conductive filler manufacturing technologies. The data showed there is no longer reason for concern over vibration and EMP stabilities of silver-glass gaskets.<<ETX>>","PeriodicalId":408694,"journal":{"name":"National Symposium on Electromagnetic Compatibility","volume":"157 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123332746","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}
Pub Date : 1989-05-23DOI: 10.1109/NSEMC.1989.37140
J. Randa, M. Kanda, D. Melquist, R. Orr
Various thermooptic designs are considered for electric-field probes for the approximate frequency range of 1-110 GHz. The designs are all based on using an optically sensed thermometer to measure the temperature rise of a resistive material in an electric field. Calculations of the sensitivities of the different designs, measurement results for the most easily fabricated design, and a discussion of possible improvements are presented. The results indicate that a probe based on this design could detect a minimum electric field of about 30-50 V/m.<>
{"title":"Thermo-optic designs for microwave and millimeter-wave electric-field probes","authors":"J. Randa, M. Kanda, D. Melquist, R. Orr","doi":"10.1109/NSEMC.1989.37140","DOIUrl":"https://doi.org/10.1109/NSEMC.1989.37140","url":null,"abstract":"Various thermooptic designs are considered for electric-field probes for the approximate frequency range of 1-110 GHz. The designs are all based on using an optically sensed thermometer to measure the temperature rise of a resistive material in an electric field. Calculations of the sensitivities of the different designs, measurement results for the most easily fabricated design, and a discussion of possible improvements are presented. The results indicate that a probe based on this design could detect a minimum electric field of about 30-50 V/m.<<ETX>>","PeriodicalId":408694,"journal":{"name":"National Symposium on Electromagnetic Compatibility","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125529183","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}
Pub Date : 1989-05-23DOI: 10.1109/NSEMC.1989.37197
Han Fang, Gao You-gang
A theoretical analysis is presented for currents along, and voltages between, sheath and core conductors induced by external sources of electromagnetic interference (EMI) in multiple-conductor underground cables. The mutual coupling among the cables of either infinite length or finite length is taken into account. The terminal effects from the boundary conditions of finitely long cables and the effect of grounding on the coupling are analyzed. The analysis is based on the model presented previously by the author (see J. Electrot., No. 1, 1989). Using this model, the general solutions to currents and potentials along the cable sheaths are first derived, and then the current in each core conductor, and the voltage between the sheath and core conductor are determined. For finitely long cables, the above model is valid if ordinary boundary conditions, i.e. the arbitrary terminal impedance between the sheath and the earth, are taken into account. These so-called terminal effects can either strengthen or restrain the influence from external EMI sources depending on their phase superposition. It is shown that the terminal effect may become less important when the cable lengths get longer. Thus, the results for infinitely long cables can be achieved when the cables are sufficiently long. Examples are analyzed for some special EMI sources such as conductive and current energizations. Satisfactory solutions to these influences are derived.<>
{"title":"A new analysis of the influence from external EMI sources on multiple underground cables","authors":"Han Fang, Gao You-gang","doi":"10.1109/NSEMC.1989.37197","DOIUrl":"https://doi.org/10.1109/NSEMC.1989.37197","url":null,"abstract":"A theoretical analysis is presented for currents along, and voltages between, sheath and core conductors induced by external sources of electromagnetic interference (EMI) in multiple-conductor underground cables. The mutual coupling among the cables of either infinite length or finite length is taken into account. The terminal effects from the boundary conditions of finitely long cables and the effect of grounding on the coupling are analyzed. The analysis is based on the model presented previously by the author (see J. Electrot., No. 1, 1989). Using this model, the general solutions to currents and potentials along the cable sheaths are first derived, and then the current in each core conductor, and the voltage between the sheath and core conductor are determined. For finitely long cables, the above model is valid if ordinary boundary conditions, i.e. the arbitrary terminal impedance between the sheath and the earth, are taken into account. These so-called terminal effects can either strengthen or restrain the influence from external EMI sources depending on their phase superposition. It is shown that the terminal effect may become less important when the cable lengths get longer. Thus, the results for infinitely long cables can be achieved when the cables are sufficiently long. Examples are analyzed for some special EMI sources such as conductive and current energizations. Satisfactory solutions to these influences are derived.<<ETX>>","PeriodicalId":408694,"journal":{"name":"National Symposium on Electromagnetic Compatibility","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129054821","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}
Pub Date : 1989-05-23DOI: 10.1109/NSEMC.1989.37177
W.B. Mieth
Hull-generated intermodulation interference (IMI) signals occur when two or more RF induced currents flow in metallic junctions having nonlinear conduction characteristics. After a brief review of the problem, the approach taken to develop a cost-effective measurement system for IMI on US Navy ships, is described. An automated IMI assessment system approach was developed to allow IMI assessment testing to occur in an accurate, timely, and efficient manner. The configuration of the automated system for intermodulation assessment (ASIA) and the interface to the shipboard transmit system are described. The system consists of three major sections: VLF/HF receiver; the radio signal distribution unit (RSDU); and microprocessor/interface unit. The half-rack IEEE-488 bus-controlled receiver performs signal detection of the interference frequencies.<>
{"title":"A cost-effective solution to measurement of hull-generated intermodulation interference on US Navy ships","authors":"W.B. Mieth","doi":"10.1109/NSEMC.1989.37177","DOIUrl":"https://doi.org/10.1109/NSEMC.1989.37177","url":null,"abstract":"Hull-generated intermodulation interference (IMI) signals occur when two or more RF induced currents flow in metallic junctions having nonlinear conduction characteristics. After a brief review of the problem, the approach taken to develop a cost-effective measurement system for IMI on US Navy ships, is described. An automated IMI assessment system approach was developed to allow IMI assessment testing to occur in an accurate, timely, and efficient manner. The configuration of the automated system for intermodulation assessment (ASIA) and the interface to the shipboard transmit system are described. The system consists of three major sections: VLF/HF receiver; the radio signal distribution unit (RSDU); and microprocessor/interface unit. The half-rack IEEE-488 bus-controlled receiver performs signal detection of the interference frequencies.<<ETX>>","PeriodicalId":408694,"journal":{"name":"National Symposium on Electromagnetic Compatibility","volume":"103 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116485650","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}
Pub Date : 1989-05-23DOI: 10.1109/NSEMC.1989.37211
S. T. Uhrich, M.C. Dosch, D.R. Bernotski
Theory, verification data, and suggested solutions are discussed for a low-frequency measurement anomaly encountered with measurement systems where the excitation and detection circuits are referenced to the same ground potential via a common shield. Drive return current is allowed to flow on the imperfectly conducting shield of the measurement circuit cable, introducing an error voltage in addition to the desired voltage. The inductance of the shield reduces this current at higher frequencies, thereby causing the error to roll off. This measurement error, caused by the transfer impedance of the shield, is most evident when measuring the small impedances commonly characterized in electromagnetic-pulse/electromagnetic-compatibility testing.<>
{"title":"Investigation of a low frequency measurement anomaly encountered with measurement systems utilizing a common shield","authors":"S. T. Uhrich, M.C. Dosch, D.R. Bernotski","doi":"10.1109/NSEMC.1989.37211","DOIUrl":"https://doi.org/10.1109/NSEMC.1989.37211","url":null,"abstract":"Theory, verification data, and suggested solutions are discussed for a low-frequency measurement anomaly encountered with measurement systems where the excitation and detection circuits are referenced to the same ground potential via a common shield. Drive return current is allowed to flow on the imperfectly conducting shield of the measurement circuit cable, introducing an error voltage in addition to the desired voltage. The inductance of the shield reduces this current at higher frequencies, thereby causing the error to roll off. This measurement error, caused by the transfer impedance of the shield, is most evident when measuring the small impedances commonly characterized in electromagnetic-pulse/electromagnetic-compatibility testing.<<ETX>>","PeriodicalId":408694,"journal":{"name":"National Symposium on Electromagnetic Compatibility","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132265559","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}
Pub Date : 1989-05-23DOI: 10.1109/NSEMC.1989.37152
G. L. Enochson, S. Kormanyos, V. Severson
A brief summary is presented of lightning tests conducted on the US Navy E-6 aircraft wing tip antenna pod/HF probe in accordance with MIL-STD-1757 to demonstrate compliance with MIL-B-5087B lightning protection requirements. The tests were conducted on a 22 ft full-sized electrically representative model of the pod/HF probe. Three types of tests were conducted. Long arc attachment tests (MIL-STD-1757 test method T01) were performed to determine the lightning arc entry angle. Direct effects testing (method T02) was conducted to examine the extent of damage which could result from a direct attachment of a high-current lightning strike to the pod. Indirect effects testing (method T05) was conducted to assess the voltage levels induced on equipment cables that result from lightning strike attachment. The waveforms applied, test article configurations, and current injection points were chosen to represent worst-case conditions. Test operations and test results are discussed.<>
{"title":"Lightning protection testing of the E-6 wing tip antenna pod/HF probe","authors":"G. L. Enochson, S. Kormanyos, V. Severson","doi":"10.1109/NSEMC.1989.37152","DOIUrl":"https://doi.org/10.1109/NSEMC.1989.37152","url":null,"abstract":"A brief summary is presented of lightning tests conducted on the US Navy E-6 aircraft wing tip antenna pod/HF probe in accordance with MIL-STD-1757 to demonstrate compliance with MIL-B-5087B lightning protection requirements. The tests were conducted on a 22 ft full-sized electrically representative model of the pod/HF probe. Three types of tests were conducted. Long arc attachment tests (MIL-STD-1757 test method T01) were performed to determine the lightning arc entry angle. Direct effects testing (method T02) was conducted to examine the extent of damage which could result from a direct attachment of a high-current lightning strike to the pod. Indirect effects testing (method T05) was conducted to assess the voltage levels induced on equipment cables that result from lightning strike attachment. The waveforms applied, test article configurations, and current injection points were chosen to represent worst-case conditions. Test operations and test results are discussed.<<ETX>>","PeriodicalId":408694,"journal":{"name":"National Symposium on Electromagnetic Compatibility","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114650639","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}
Pub Date : 1989-05-23DOI: 10.1109/NSEMC.1989.37156
L. Hoeft, J. Hofstra, R.J. Karaskiewcz
An in-situ system-level upset test technique has been developed that uses a random repetitive square wave pulse generator (R/sup 2/SPG) as a broadband simulator. In the proposed technique current is inductively coupled to cables or cable bundles and is easily controllable from amplitudes of 10 mA to 16 A peak-to-peak. The waveform is a broadband transient that approximates a damped square wave with a ringing frequency that is related to the resonant frequency of the cable to which it is connected and the length of the charge line and connecting cables. The pulses are generated with a random interval between pulses. The average repetition rate can be as high as 30 Hz. The pulse generator is described, typical waveforms are presented, and it is shown how the generator can be used to determine the upset threshold of a digital system by presenting results for a personal computer.<>
{"title":"R/sup 2/SPG-a new technique for measuring upset susceptibility thresholds of large systems","authors":"L. Hoeft, J. Hofstra, R.J. Karaskiewcz","doi":"10.1109/NSEMC.1989.37156","DOIUrl":"https://doi.org/10.1109/NSEMC.1989.37156","url":null,"abstract":"An in-situ system-level upset test technique has been developed that uses a random repetitive square wave pulse generator (R/sup 2/SPG) as a broadband simulator. In the proposed technique current is inductively coupled to cables or cable bundles and is easily controllable from amplitudes of 10 mA to 16 A peak-to-peak. The waveform is a broadband transient that approximates a damped square wave with a ringing frequency that is related to the resonant frequency of the cable to which it is connected and the length of the charge line and connecting cables. The pulses are generated with a random interval between pulses. The average repetition rate can be as high as 30 Hz. The pulse generator is described, typical waveforms are presented, and it is shown how the generator can be used to determine the upset threshold of a digital system by presenting results for a personal computer.<<ETX>>","PeriodicalId":408694,"journal":{"name":"National Symposium on Electromagnetic Compatibility","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121180474","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}
Pub Date : 1989-05-23DOI: 10.1109/NSEMC.1989.37205
J. Poltz, A. Wexler
A description is given of a new release of Greenfield, a family of analog simulation software tools that simulate the behavior of multilayer printed-circuit boards (PCBs) under high-speed switching conditions. Per unit length inductance, capacitance and resistance matrices-for systems of coupled multiconductor microstrips and striplines-are produced by the two-dimensional Green's function boundary-element field solver Greenfield2d. Greenfield2d supports generation of different SPICE subcircuit models of coupled transmission lines. These models can be subsequently used in Phyllis or any tool which supports SPICE netlist syntax. Cross-sections of multiconductor structures including stripline, microstrip and no-ground connections are shown. The boundary-element procedure is used to generate circuit models for these electromagnetically coupled structures. Time-domain signals and cross-talk waveforms are shown in the time domain.<>
{"title":"Cross-talk and ringing on a multilayer PCB","authors":"J. Poltz, A. Wexler","doi":"10.1109/NSEMC.1989.37205","DOIUrl":"https://doi.org/10.1109/NSEMC.1989.37205","url":null,"abstract":"A description is given of a new release of Greenfield, a family of analog simulation software tools that simulate the behavior of multilayer printed-circuit boards (PCBs) under high-speed switching conditions. Per unit length inductance, capacitance and resistance matrices-for systems of coupled multiconductor microstrips and striplines-are produced by the two-dimensional Green's function boundary-element field solver Greenfield2d. Greenfield2d supports generation of different SPICE subcircuit models of coupled transmission lines. These models can be subsequently used in Phyllis or any tool which supports SPICE netlist syntax. Cross-sections of multiconductor structures including stripline, microstrip and no-ground connections are shown. The boundary-element procedure is used to generate circuit models for these electromagnetically coupled structures. Time-domain signals and cross-talk waveforms are shown in the time domain.<<ETX>>","PeriodicalId":408694,"journal":{"name":"National Symposium on Electromagnetic Compatibility","volume":"167 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1989-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121571593","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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