INTERNATIONAL SESSION ON ELECTRO-MECHANICAL DEVICES 2004 (IS-EMD 2004)

INTERNATIONAL SESSION ON ELECTRO-MECHANICAL DEVICES 2004 (IS-EMD 2004)
co-located with 5^thChitose International Forum on Photonics Science & Technology (CIF'5)

(Record and Abstract)
October 21-22, 2004
Chitose Institute of Science & Technology Chitose, Hokkaido, Japan

Sponsorship:: Technical Committee of EMD in Institute of Electronics, Information and Communication Engineers.
Co-sponsored:: Research and Engineering Meeting of Electromechanical Components and Contact Technology, and Chitose Inst. of Science & Technology.

Technical program
Thursday, October 21, 2004

<<Session1>> - Optical Interconnection -

1. EMD2004-56: Design concept of bidirectional multifiber WDM networks for metro areas; Hitoshi OBARA and Masato SAKATA (Department of Electrical and Electronic Englneering, Akita University); A new feasible design of multifiber WDM ring networks using two identical sets of wavelengths for opposite directions on a single fiber is described. A numerical analysis shows that optical power penalty due to Rayleigh backscattering can be reduced less than 1 dB with the help of simple optical edge filters. These results make multifiber WDM networks more attractive for high-capacity WDM networks for metro areas.

2. EMD2004-57: 16-fiber fiber physical contact connector with compact shutter utilizing coupling mechanism of MU connector; Yoshiteru ABE, Masaru KOBAYASHI and Ryo NAGASE (NTT Photonics Laboratories, Nippon Telegraph and Telephone Corporation); Optical connectors for printed circuit board interfaces are required for the implementation of high-density multi-fiber connection. We have developed a 16-fiber fiber physical contact (FPC) connector to meet this requirement. In the FPC connector, two arrays of fibers are aligned in micro-holes without ferrules, and contact is maintained by the pressure generated by the elasticity of the fibers. The FPC connector has to ensure the reliability to the use of bare fibers. Moreover, the FPC connector must provide a more reliable coupling mechanism and higher density connection. To meet these requirements, we employ the MU connector coupling mechanism and a shutter, and we connect 16 fibers in the housing of the duplex MU connector. We developed compact shutters that open only when they come into contact with each other. The developed 16-fiber FPC connectors had an average insertion loss of 0.06 dB and a return loss of over 45 dB. The optical performance remained stable in environmental and mechanical tests.

3. EMD2004-58: Novel Stacked Packaging Structure Using Silica-based PLC with Integrated Micro-mirrors and its Application to an 8ch PD Array Module; Ikuo Ogawa, Yoshiyuki Doi, Makoto Abe and Senichi Suzuki (NTT Photonics Laboratories, NTT Corporation); We have developed a new stacked packaging technique using silica-based PLCs with integrated micro-mirrors and successfully applied it to the fabrication of an 8-channel PD-array module. The module showed excellent characteristics such as a high responsivity of > 0.85 A/W and a low crosstalk of < -65 dB.

4. EMD2004-59: Smart optical board packaging of delivery and coupling switch utilizing super-multi-fiber PLC connector; Masaru Kobayashi (NTT Photonics Laboratories, Nippon Telegraph and Telephone Corp.), Shuichiro Asakawa(NTT BizLink Corp.), Yoshiteru Abe, Ryo Nagase, Hiroshi Takahashi (NTT Photonics Laboratories, Nippon Telegraph and Telephone Corp.); We applied a super-multi-fiber PLC connector for connecting up to 64 ch to the board packaging of an 8 x 8 delivery and coupling switch (DC-SW) module with a fiber sheet. The DC-SW module is composed of plural PLCs and needs a large amount of fiber crossing. The PLC connector can attach fibers to and remove them from a PLC endface and realizes a PLC receptacle module instead of a PLC pigtail module. The fiber sheet resolves the problem of fiber congestion. We demonstrate the smart optical fiber wiring and board packaging of a DC-SW whose optical performance matches that of a conventional switch in which the pigtail fibers of the PLC modules are fusion spliced and squeezed into a package.

<<Session2>> - Arc Discharges & Related Phenomena -

5. EMD2004-60: The arc movement simulation in simplified chamber of low-voltage circuit breaker on different conditions; Yi Wu, Mingzhe Rong, Qian Yang, Guangxia Hu (Xi'an Jiaotong Univ.); This paper is devoted to simulate the arc movement in the simplified chamber of low-voltage circuit breaker. Based on a group of governing equations, a three-dimensional (3-D) arc model is built and solved by a commercial code. According to the simulation results, an arc shrinkage phenomenon happens near the electrode and the head of arc column in x-z plane looks somewhat like part of an ellipse. A 'bulge' visible in the front of the arc column and a trail in the rear are described in detail. Additionally, accompanied with some interrelated experimental data, the influence of external magnetic field and geometry configurations of the arc chamber on the arc motion is also discussed and analyzed.

6. EMD2004-61: Measurements of minimum arc current for Ag and Pd contacts; Yusuke KAMADA and Makoto HASEGAWA (Department of Applied Photonics System Technology, Chitose Institute of Science and Technology); Arc discharges often lead to serious contact failures when electrical contacts operate. Although values of so-called minimum arc current for various contact materials are often referred to as the lower limit over which no arc discharges are expected to occur at contact operations, damages apparently related to arc discharges can be observed even when contacts operate in very-light load region. In this paper, arc occurrence rates are measured for Ag and Pd contacts operated in a DC resistive load circuit. Based on the obtained results, it is confirmed that arc certainly occurs at current levels lower than the conventional minimum arc current value for each of the tested contact materials. Arc occurrence rate in general comes close to 100% at the conventional minimum arc current level. Accordingly, careful attention should be paid to use of the term "minimum arc current" in order to avoid misinterpretation thereof.

7. EMD2004-62: Comparison between the Surface Condition of Electrical Contacts and the Behavior of breaking Arcs Observed with a High-speed Camera; Junya Sekikawa, Tetsuya Kitajima, Takayoshi Endou, Takayoshi Kubono (Faculty of Engineering, Shizuoka University); The relationship between the condition of contact surfaces and the motion of arc spots are investigated in DC 42V/10A resistive circuit using a microscope and a high-speed camera for Ag electrical contacts. Surface conditions of electrical contacts are observed with the microscope after each breaking operation. As results, the diameters of the cathode and anode spot regions that are obtained by using a high-speed camera are almost corresponding to photographs of the traces of the erosion by a microscope. And the films on the cathode surface may be generated at different stage of the arc duration.

8. EMD2004-63: Cathode and anode bright spot behaviors of breaking arc between electrical contacts with the low separating speed; Takayoshi Endou, Junya Sekikawa, Takayoshi Kubono (Shizuoka Univ.); In each contact material (Ag, Cu, Ni, and Fe), the breaking arc occurring between electrical contact pair in resistive circuit of DC42V/10.5A were observed with a high-speed camera (1000 frames/s). Arc voltage and arc current were also measured simultaneously. By analyzing cathode and anode bright spots in the photographs, the position of cathode and anode bright spots on contact surfaces were plotted on the screen. As a result, cathode and anode bright spots were expressed the characteristic motion in each material. Moreover, by comparing those results with the photograph of contact surface after all operations, we considered the damage process of the contact surface by the breaking arc.

<<Session3>> - Relays -

9. EMD2004-64: Load Limits of Ultra Miniature Electromechanical Signal Relays; Werner JOHLER (Tyco Electronics AXICOM, Switzerland) and Alexander NEUHAUS (AC2T research GmbH, Austria); Modern telecom and signal relays have been optimized to carry and switch low signals and to withstand high dielectric strength. Recent designs have extremely small physical dimensions and are comparatively cheap. Small size and low cost also make this type of relay very attractive for industrial and automotive applications. For industrial and automotive applications performance characteristics other than low and stable contact resistance values are of importance. While, for industrial applications, safety aspects and inductive load switching characteristics are of major importance, in automotive applications, high switching currents, inductive and lamp loads and high ambient temperatures are essential. Tests were carried out in order to determine the limitations of small size relays. The results obtained clearly show the unexpectedly high load range which signal relays are able to cover. Despite their small size, these relays can handle switching loads up to several hundred volts and currents up to 5 A. On top of the high switching current there is high excess current capability, and relays can work at extreme ambient temperatures between -55 and more than +105 degrees C.

10. EMD2004-65: Fabrication process of non arcing power MEMS relay; Yu Yonezawa, Noboru Wakatsuki (Ishinomaki Senshu Univ.), Yoshio Sato, Tadashi Nakatani (Fujitsu Laboratories Ltd.), Koichiro Sawa (Keio Univ.); We proposed a new electric contact device that suppresses the arc phenomena. Electric contact functions are divided into energizing and switching. Switching contacts are the multi electrodes and each electrode current is suppressed by series resistance. For realizing of the multi contacting, cantilever beam array electrodes were formed on silicon substrate using Micro-electromechanical Systems (MEMS) technology. Finite element method was used for optimizing structure. Fabrication process of cantilever was examined. 0.97A of contact current was broken by the Au plating electrodes.

11. EMD2004-66: Time-coordinated switching relay for arc discharge suppression; Noboru Wakatsuki, Yu Yonezawa and Yuuichi Akiba (Department of Infomation Teclmology and Electronics, Faculty of Science and Engineering, Ishinomaki Senshu University); We propose a new electric contact device for stable arc discharge suppression. The functions of conventional electric contacts are categorized into energizing contacts and transient current contacts. A capacitor is connected in series to transient current contacts. Suppression of power consumption and arc discharge at breaking contacts are proposed, experimentally measured, and theoretically analyzed. The transient V-I characteristics at breaking contacts are controlled by the transient current switch and the capacitor. The transient responses at contacts were numerically derived by SPICE, and the transient contact current or contact voltage could be controlled to less than the minimum discharge current or the minimum discharge voltage, respectively. Using 2 conventional relay contacts, no stable arc break operation was confirmed for 50V/25A.

Friday, November 15, 2002
<<Session4>> - Signal Transmission -

12. EMD2004-67: Electrical-thermal current carrying capacity simulation of a printed circuit board connector; Horst F. Nowacki, Achim Brenner (HARTING KGaA); This technical contribution describes a conventional measurement setup for the determination of current carrying capacity of connectors specifically designed for heavy current applications in connection with printed circuit boards. In this model arrangement the physical factors influencing current carrying capacity are examined in terms of the execution of conducting tracks and the layer construction of the printed circuit board. In the course of the electrical-thermal simulation of a measuring routine utilizing the finite element method, the authors discuss the various influencing parameters. In this context, the individual elements of the model such as the input of individual wires, the printed circuit board itself with its conducting track widths and the execution of the connector are of particular significance. The simulation model selected is in continued use in order to determine the current carrying capacity of connectors with parallel-switched contacts. Here, particular emphasis is on discussing the influence of deviating constriction resistance of parallel-switched contacts. This parallel switching of contacts with lower current carrying capacity is especially interesting for the cost efficient utilization of components for industrial applications, as the component's high number of poles provides many contacts for practical applications and thereby enables parallel switching.

13. EMD2004-68: Characteristics of electromagnetic radiation from a surface microstrip line structure at high frequency; Yoshiki Kayano, Motoshi Tanaka, Hiroshi Inoue (Akita Univ.); It has been demonstrated that a common-mode (CM) can dominate an entire radiation up to 1GHz, despite the fact that a CM current is smaller than a differential-mode (DM) current. In this paper, the characteristics of electromagnetic radiation from a surface microstrip line structure at high frequency (a few gigahertz) are newly studied experimentally and with finite-difference time-domain modeling. Several different configurations are prepared to compare CM to DM component. The results show that the entire radiation up to 1GHz is related to CM component. The increase in entire radiation at higher frequencies could not be predicted from only the frequency response of CM current. At the higher frequencies, DM component may be more significant relative to the CM component.

14. EMD2004-69: A study on transmission and undesired radiation characteristics of mount model for high frequency element; Hiroshi Inoue, Takashi Kasuga, Yoshiki Kayano (Akita Univ.), Kenji Tan, Kiyoshi Yamakawa (Akita Research Inst. of Advanced Technology); Recently, a transmission line, which is applicable to a small magnetic probe that has impedance change at high frequency, is required. In this paper, transmission characteristics of mount model for high frequency element are studied experimentally and with finite-difference time-domain (FDTD) modeling. Several different configurations as mount model are prepared for comparison of the transmission characteristics. The results suggest that, if applicable conditions of transmission line which connects the sensor element are clarified, variation of the impedance of the sensor in a few ohms range can be detected. This study is a basic consideration to develop a technique which mounts high frequency element.

Thursday, October 22, 2004

<<Session5>> - Contactors & Circuit Breakers -

15. EMD2004-70: Measurement of the Dielectric Recovery Strength and Reignition of AC Contactors; Chen Degui, Li Xingwen and Dai Ruicheng (School of Electrical Engineering, Xi'an Jiaotong University, China); In order to understand the recovery characteristics of AC contacts and improve their performance, experimental measurements were used to investigate the arcing gap recovery process including dielectric recovery strength and reignition, to a pair of splitter plate together and four kinds of arc chamber of AC contactors. A special circuit was designed to perform the work. It demonstrates that under lower current, the dielectric recovery strengths of all kinds of arc chambers in the paper have no significant difference. However, with the increase of current, the difference of dielectric recovery strengths of them is much clear. The reignition characteristics of a pair of splitter plate and arc chambers are similar. With different configurations of arc chambers and prospective currents, the forms of post current zero reignition are distinct.

16. EMD2004-71: Investigation on the dynamic characteristics of a magnetic release in molded case circuit breaker; Xiang Honggang, Chen Degui, Li Xingwen, Tong Weixiong (Xi'an Jiaotong Univ.); A method is proposed to investigate the dynamic characteristics of a magnet release in molded case circuit breaker. With the static field assumption, two grids of the magnetic torque and flux linkage are calculated with the variation of the current and air gap, firstly. Considering the influence of tripping force, coupled with circuit equation and mechanism motion equation, the dynamic characteristics may be obtained with Runge-Kutta 4 method. Experiments have been done to verify the method. In addition, the influence of the reaction spring on the operation characteristic is analyzed. It demonstrates that the difference of the protection characteristic curve between experiment and simulation is below 10%, and it is easier to adjust the initial length of the reaction spring to meet the requirement of different rated current and operation current, relative to adjust the stiffness of the reaction spring.

17. EMD2004-72: Mechanical Condition Monitoring of Vacuum Circuit Breakers Using Artificial Neural Network; Yongpeng Meng, Shenli Jia and Mingzhe Rong (Xi'an Jiaotong Univ.); The vibration signature collected on the framework of the vacuum circuit breaker is decomposed into individual frequency bands using the algorithm of wavelet packets. Main signal energy in these bands is extracted to form the condition eigenvectors. For specific condition classification, the concept of credibility is introduced in this paper. A new recognition algorithm based on the Radial Basis Function (RBF) neural network is proposed and applied to the monitoring of vacuum circuit breakers. Multiple experiments under different conditions verify that the new algorithm can recognize not only the known conditions but also a new condition of the breakers.

<<Session6>> - Sensing Devices -

18. EMD2004-73: A new method to calculate the frequency characteristics of the Rogowski coil based on the frequency simulation; Xiaoshe Zhai, Yingsan Geng, Zhengxiang Song, Jianhua Wang, Jianjun Yao (Xi'an Jiaotong Univ. Xi'an ,China ); In the high frequency measurements, Rogowski coil's distributed resistance, capacitance and inductance may cause the resonance of the measuring circuit, which limits the measuring bandwidth. In this article, a new method based on high frequency simulator (HFSS) is adopted which can provide a convenient way to achieve more precise frequency characteristics. At the same time, the influence of the terminal impedance is discussed, so a proper damping impedance can be selected to improve the coil' frequency characteristics.

19. EMD2004-74: Optimization of Magnetic Circuit Geometry for Eddy-current Type Proximity Sensor; Koichi Koibuchi, Koichiro Sawa (Keio Univ.), Takashi Honma, Takumi Hayashi, Kuniyoshi Ueda and Hiroshi Sasaki (Yamatake Corp.); Eddy-current type proximity sensor is a non-contact type sensing device to detect the approach of a conductor by increase of eddy current loss in the target conductor. In this paper, actual proximity sensor is firstly calculated by FEM to verify the validity of numerical analysis results and study about electromagnetic properties of proximity sensor. Furthermore, two models that are modified magnetic circuit geometry based on the actual sensor are proposed and calculated by FEM. Results of numerical experiences are shown as enhanced sensing properties. In conclusions, knowledegs about optimal design for magnetic circuit geometry of the proximity sensor are shown.

<<Session7>> - Contact Phenomena -

20. EMD2004-75: Correlation between Contact Resistance Characteristics and STM Images for Ag-Pd Alloy with Some Additives; Terutaka Tamai (Hyogo University of Teacher Education); STM image is composed by tunnel current. The tunnel current is strongly depending on applied voltage between specimen surface and a probe tip, and on work function of the specimen surface. Therefore, STM image is different from optical images. Under certain applied voltage, the distribution of work function on the surface is directly relates to the image. In the present paper, in order to understand the STM images on the contact surface, surfaces of Ag-Pd alloys with Mg and Cr additives were subjected to the STM. The additives are easily oxidized, their oxide distribute on the surface. Therefore the effect of the additives on the STM image could observe. For Ag-Pd-Cr, in both case of clean and oxidized surface, as CrO and Cr2O3 of Cr oxide are typical insulators, sharp projections such as needles were shown in the images which are very different from optical microscope image. And high contact resistance was measured. On the other hand, for Mg, MgO showed conductive, therefore, smooth surface obtained as the STM image. Contact resistance showed very low level. Even if the oxide grew under heating, same tendency were obtained. Conductivity of oxides on the surface greatly effect on the images. Correlation between contact resistance and the STM images was found. key words: STM, contact resistance, Ag-Pd-Cr alloy, Ag-Pd-Mg alloy.

21. EMD2004-76: Characteristics of a sliding system with Au-plated slip-ring and AgPd brush for power supply; Koichiro Sawa, Takashi Shigemori, Yosuke Kawakami (Keio Univ.), Gun Ou, Kaoru Endo, Hiroshi Hagino (Japan Servo Co., Ltd.); Sliding contact is still an important mechanism to transmit current or electric power from a stationary equipment to a moving device. A power supply slip-ring used in a chip mounter is presently 20 millions rotations in life, but expected to have more life time. In this paper slip ring with Au plated on Ni plated base layer is investigated in reliability against AgPd brush. Test conditions are 400rpm in rotation speed and 5A in operation current. Contact resistance and surface morphology are observed with operation time. Consequently, in some case the Au-plated layer is worn out about 15 millions rotations, but contact resistance stays low and stable during the test of 20 millions rotations. Compared with no load current rings the contact resistance of rings with load current is usually lower. Further, the relation between contact resistance degradation and sliding surface change is discussed.

22. EMD2004-77: Relation between ambient temperature and contact voltage drop of sliding contacts; Takahiro Ueno, Noboru Morita (Nippon Inst. of Technology); The sliding contact surfaces of rotating slipring or commutator and brushes of motor are influenced by friction. The brush wear are influenced by brush pressure, current density and ambient atmosphere near by the contact part. However, little is known about the relation between brush wear and atmosphere condition in detail. The sliding part of brush and slipring is put into the sealed box and temperature inside the box is kept on the specified condition by temperature control system. The contact voltage drop, brush wear are observed.

23. EMD2004-78: Relationship between length and diameter of contact bridge formed under thermal equilibrium condition; Hiroyuki Ishida, Masanari Taniguchi (Tohoku Bunka Gakuen Univ.), Hideaki Sone (Tohoku Univ.), Hiroshi Inoue (Akita Univ.), Tasuku Takagi (Tohoku Bunka Gakuen Univ.); From the authors' investigations on the initial instantaneous phenomena in breaking contacts, we have found the two types of bridge, i.e. one is a brightened (luminous) bridge and another one is a dark (non-luminous) one. This paper discusses on the dark bridge formed between contacts when the separation speed is very small. The following items are mentioned in this paper: a)bridge model and theory on the relationship between bridge length and diameter. b) thermal flow from bridge to its vicinity, c) deduction of a thermal equilibrium condition from the calculation of thermal flow time constant. d) experimental works, e) discussions and f) conclusions. In conclusion, we see the coincidence of the tendency of the theory and experiment carried out on the relationship between bridge diameter and length.

<<Session8>> - Automotive Application -

24. EMD2004-79: Temperature measurement of breaking arcs between Cu-Cu, Ni-Ni and Pd-Pd contact pairs in a DC 42V-10A circuit; Tetsuya Kitajima, Junya Sekikawa (Shizuoka Univ.), Mitsuru Takeuchi (Nagoya Municipal Industrial Research Institute), Takayoshi Kubono (Shizuoka Univ); The purpose of this work is to examine the differences of the arc temperature among three electrode materials and the impact of the opening speed on breaking arc. Three electrode materials are Cu, Ni and Pd, and the opening speeds are 5, 10, 15 and 20 mm/s. The breaking arc is generated in a D.C 42V/10.5A circuit, and the arc voltage, the arc current and the spectrum intensity are measured. Arc temperature is calculated by using a Boltzmann plot. As it turned out, the arc temperature is about 5500~8000K for Cu contacts, 4500~8500K for Ni contacts and 8500~11500K for Pd contacts. Besides, the opening speed of 5, 10, 15 and 20mm/s has no influence on the arc temperature for Cu, Ni and Pd contacts.

25. EMD2004-80: Observation of Pips Formed on Ag/SnO2 Contacts in DC14V-20A Resistive Circuit; Yutaka NAITO, Takayoshi KUBONO, Junya SEKIKAWA, Ryo YAMAZAKI and Tomoya ITO (Shizuoka Univ.); We tested Ag/SnO212wt% contacts mounted on electromagnetic relay in the resistive circuit of DC14V-20A as make-only-contacts, and took pictures of transferred pips formed on cathode surface. In this experiment, we predict that if the relation of "H/Dr>=0.5 and H/Ga>0.5" is realized, the possibility that sticking will happen at contacts is very high, when the movable side of contacts is cathode. Where H is height of pip, Dr is thickness of pip (diameter of root of pip), and Ga is gap length of contacts. We also find situations of growth are different when the movable side is anode.

26. EMD2004-81: Growth of transferred pip and electrical property on AgCdO make-only contacts in a resistive circuit with dc 14V and 42V power supply; Tomoya Ito, Ryo Yamazaki, Yutaka Naito, Junya Sekikawa, Takayoshi Kubono (Shizuoka Univ.); AgCdO12wt% contacts mounted on electrical relays were tested in a dc 14V-21A and 42V-8.4A resistive circuit as make-only contacts. In this experience, we took photograph records and measured arc duration and number of bounces. The transferred pip has been grown on cathode surface, and its height H has grown "H/Gap>0.5",sticking have occurred easily. Rapid of growth or shape of the transferred pip have not influenced circuit condition, but there is a difference from each sample. Since arc discharge of switching operations at make-only contacts occurs during a rebound, arc duration as well as number of bounce fluctuates.