IEEJ Transactions on Industry Applications
Online ISSN : 1348-8163
Print ISSN : 0913-6339
ISSN-L : 0913-6339
Volume 122 , Issue 2
Showing 1-20 articles out of 20 articles from the selected issue
  • Genichi Taguchi
    2002 Volume 122 Issue 2 Pages 83-88
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    Download PDF (1121K)
  • Yuichi TOKUNAGA, Seiichi SAITO, Minoru SHIGA
    2002 Volume 122 Issue 2 Pages 89-95
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    This paper proposes a novel method to cleanse electric contacts in a digital input system with low power consumption, which is suitable for industrial computer systems such as substation control systems. Oxygenated membrane on the surface of the contacts is kept away by generating small arcs when the contacts open or close. In order to reduce power consumption, the state of the contacts has to be monitored at low current. On the other hand, high current is needed to generate arcs. Our circuit can solve the problem by only supplying enough the current to generate arcs when the contact has been opened or closed. The mechanism to generate arcs is clarified experimentally and analytically, and it is shown by simulation that the proposed circuit can generate small arcs despite low power consumption.
    Download PDF (1360K)
  • Kohji Higuchi, Kazushi Nakano, Kuniya Araki, Fumiho Chino
    2002 Volume 122 Issue 2 Pages 96-103
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    A method is proposed for designing a robust controller for PWM power amplifiers, which are widely used as amplifiers themselves and power supplies. The main technical requirements imposed on PWM power amplifiers are linerarity in wide frequency range and well-damped fast dynamic response against extensive load and d. c. power supply variations. Therefore, in order to satisfy the design specifications-linearity in wide frequency range and no overshoots during the transients, an approximate 2-degree-of-freedom integral type control structure is proposed as well as a design procedure for the robust controller is discussed. It is clarified from some simulations and experiments that the designed controller shows highlighted good dynamic performances and effective disturbance rejection properties against external disturbances, i. e. load and power-supply variations.
    Download PDF (2392K)
  • Zhongping Yang, Takafumi Koseki, Satoru Sone
    2002 Volume 122 Issue 2 Pages 104-110
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    It is an important factor for railway services to take proper train rescheduling under disrupted conditions. This paper discusses the rescheduling problem in the case of resumption of train operation, in which the train operation has been temporarily suspended by an accident. The authors propose a novel rescheduling method using selective stops schedule pattern. The proposed rescheduling problem has been formulated as a nonlinear optimization problem, and it has been solved by the simulated annealing method. Finally, the proposed methods are applied to a typical commuter line, and the efficiency of these methods has been verified through simulations.
    Download PDF (1114K)
  • Kazushi Nakano, Tetsuya Tabaru, Seiichi Shin, Yukihiro Toyoda, Taro Ts ...
    2002 Volume 122 Issue 2 Pages 111-119
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    The procedure for identifying linear time-varying systems with dead times using the wavelet analysis has already been proposed by the authors. This paper reports an application of the identification procedure to actual control systems of watertube drum-boiler in a thermal power plant. The control systems are required to supply steadily high-quality steam subject to disturbances due to unexpected changes in load. Therefore, it is necessary to make a precise model which takes the disturbances into consideration for control system design. The identification procedure is applied by the following steps: (1) extension of the method for single-input/output systems to that for two-input/output systems, (2) estimation of the time span where the system is considered to be in steady states, and (3) estimation of the process transfer functions in each time span. The identified model is evaluated in terms of mean square errors of the process outputs (steam-pressure and water-level) in comparison with an ARX model.
    Download PDF (3096K)
  • Kiyoshi Ohishi, Emiko Hayasaka, Tetsuaki Nagano, Masaya Harakawa
    2002 Volume 122 Issue 2 Pages 120-127
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    A robust servo system is important for performance improvement of motion control systems to several industry applications. Generally, these robust servo systems are constructed as PI controllers, H controllers and so on. These control systems have the output limitation concerning both the capacity of actuator and the safety of system. When a servo system with integral element has a large error input, it often leads to output saturation and sometimes a windup phenomenon takes place. Ordinarily, in order to overcome this problem, the conventional anti-windup approach is to stop integral and additional calculations of servo system. However, the speed servo system with the conventional anti-windup algorithm sometimes has an oscillated response, and moreover, the actual voltage limitation is carried out on the axis of three phase alternating current. This paper proposes both a new anti-windup algorithm considering the phase voltage saturation and a new phase compensation algorithm for the vector control system of induction motor. The experimental results and the numerical simulation results show that the speed servo system having the proposed algorithms regulates a motor speed smoothly and stably for a large and quick motor speed reference.
    Download PDF (1746K)
  • Masashi Nakamoto, Akimasa Nakai
    2002 Volume 122 Issue 2 Pages 128-134
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    In this paper multivariable control and PI control are combined with cascade connection for an once-through type heat recovery boiler with multiple evaporators. An LQR design method has been applied to develop a decouplling controller for an interactive feedwater control of a heat recovery boiler. PI control has been applied to regulate outlet steam quality of each evaporators.
    Download PDF (1304K)
  • Toshiro Kumon, Tatsuya Suzuki, Makoto Iwasaki, Motoaki Matsuzaki, Nobu ...
    2002 Volume 122 Issue 2 Pages 135-143
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    The requirement for the high quality control of complex and/or structure-unknown plant is growing in the real-world industrial machine. Indiect Adaptive Control (IAC), which identifies model and updates the controllers automatically, is expected as on of the promising way to meet this requirement. The conventional IAC, however, required to know the structure of the structure of the controlled plant, i.e. the order of its transfer function in advance. This paper presents a new IAC scheme which makes use of Genetic Algorithm (GA) in its identification part. In the proposed framework, the information on the order of the plant is not required since GA searches both the structure of the plant dynamics and its parameters autonomously. A two-degree-of freedom Internal Model Control (IMC) is adopted as a basic control architecture since the indirect adaptation can be harmoniously embedded in it. The effectiveness of the proposed scheme is verified though numerical simulations and experiments applied to a velocity control of multi-mass systems.
    Download PDF (2370K)
  • Tadashi Yamaguchi, Yoshihiro Kawase, Masataka Torizawa, Hirokazu Sekin ...
    2002 Volume 122 Issue 2 Pages 144-149
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    Stepping motors have a high level of positioning control so that they are widely used in the field of OA machine tools and so on. Therefore, for the optimum design of these electromagnetic devices, it is necessary to analyze the dynamic characteristics of stepping motors. Stepping motors used in wristwatches are ones of the smallest stepping motors and are required a high accuracy of motion. However, it is difficult to obtain the accurate dynamic characteristics of them experimentally due to the small size. In this paper, the dynamic characteristics of a stepping motor for wristwatches are analyzed using the 3-D finite element method coupled with the electric circuit and the motion equation. In this analysis, the load of the gears is taken into account as the inertia of rotor in order to simulate the actual condition. The chopped voltage waveform is applied to the stepping motor. Thus, the time variations of the rotation angle and the exciting current are calculated, and the validity of our method is confirmed by the experiments.
    Download PDF (1475K)
  • Yoshihiro Kawase, Tadashi Yamaguchi, Masatoshi Ito, Katsuhiro Hirata
    2002 Volume 122 Issue 2 Pages 150-155
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    In this paper, thrust characteristics of a linear pulse motor for the use of automatic doors driven by 2-phase excitation are computed using the 3-D finite element method. The effectiveness of this calculation is verified through the comparison with the measured results. The influences of the excitation control on the thrust characteristics are investigated. Furthermore, the influences of loads on dynamic performances are investigated.
    Download PDF (2486K)
  • Takashi HIKIHARA, Tomoki YOSHIDA, Yoshisuke UEDA
    2002 Volume 122 Issue 2 Pages 156-161
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    Recently, magnetic levitation systems which suspend thin steel plates are widely discussed for demands on high quality steel production. The noncontact suspension has a possibility for producing nondamaged plates. Steel plates have the continuously distributed structure. Then it is difficult to arrange discrete magnets without an appropriate model of the bending dyanamics. In this paper, the Bernoulli-Euler model of a thin steel plate is proposed. The dynamical characteristics of a steel plate under vibration are discussed based on the model and experimental results. As results, it is clarified that the model has a limit of application to describe the bending behavior of a steel plate. The model may give us the information to decide the arrangement of electric magnets in the levitation system.
    Download PDF (1719K)
  • Akio Toba, Toshiharu Watanabe, Yoshinori Koganei, Hiroshi Ohsawa
    2002 Volume 122 Issue 2 Pages 162-168
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    This paper presents experimental evaluations of 5kW-level Surface Permanent Magnet Vernier Machines (SPMVM). The SPMVM has a feature of high-torque with low current loading, and thus has a possibility to achieve high torque and high efficiency at once, which is difficult with the conventional permanent magnet machines. Following to a brief explanation about the design of the prototype machines, experimental results are brought about, which show good agreements between the designed and measured characteristics. The experiments reveal that the SPMVM inherently has relatively low power factor, which is below 0.6 this case. It is also confirmed that the cogging torque becomes about 2 to 3% of the rated torque because of slight magnetic unbalances in the prototypes. As a conclusion, the most attractive features of the SPMVM are high torque density and low power loss, and thus the SPMVM is suitable for the applications that require high torque constantly, and that the weight or volume limitations are strict.
    Download PDF (1917K)
  • Youichi Ito, Satoru Ishiguma, Yuichiro Kanno, Hideyuki Iida, Yasuhiro ...
    2002 Volume 122 Issue 2 Pages 169-175
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    This paper describes a new power conversion method for single-phase uninterruptible power supplies (UPSs). Existing power conversion methods for UPSs can be divided into three categories; off-line, line-interactive and on-line methods. Generally, the line-interactive methods have better efficiency than the on-line method, while the on-line methods give better input and output characteristics than the line-interactive methods. The proposed method has the merits of these methods and provides a high efficiency with maintaining an excellent input and output characteristic. The main circuit based on this new method consists of three phase arms, which operates as a boost converter, a step-down converter, and a power active filter, respectively. Switching loss is significantly reduced by operating the two converters in PWM mode only when necessary. Testing results on a commercialized 1kVA UPS based on the proposed method show a maximum overall efficiency of 94%. Moreover the input and output characteristics are as good as those of the traditional on-line UPSs.
    Download PDF (993K)
  • H. Itoh, T. Inamoto, T. Uchiyama, K. Mohri
    2002 Volume 122 Issue 2 Pages 176-181
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    We propose a new car sensing system using two amorphous wire CMOS magneto-impedance (MI) sensor built in a disk set on the road. When a car passes above the disk, two MI sensors detect stray field from the car body The speed and length of a car can be estimated using the signals detected with the two MI sensors. We used a cross correlation function to detect the time interval between two detected waveforms. The proposed sensing system is useful not only for a traffic control but also for a traffic census for an environmental design of a big city residence.
    Download PDF (2652K)
  • Hirokazu Seki, Yoichi Hori
    2002 Volume 122 Issue 2 Pages 182-188
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    Japan is now a serious aging society and this problem will be more serious in the near future. Therefore, engineering support for aged people is required. As an important example of such support, a monitoring system for aged people is proposed in this paper. This system automatically learns aged people's usual actions in a few days and detects his/her abnormal action by observing the room with a simple camera such as CCD camera.
    At the learning stage, Self-Organizing Map (SOM) is used to realize automatic learning. For the detection method, Eigenspace Method is used which is excellent in compression of image data and calculation of the correlation among images. Parametric Eigenspace Method(PEM) is also used to detect abmormalities such as the speed of the action. Some results show the effectiveness of the proposed method.
    Download PDF (6951K)
  • Kenji Kariya, Muneaki Ishida
    2002 Volume 122 Issue 2 Pages 189-190
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    This paper deals with the high-frequency equivalent circuits of an induction motor and a PWM inverter considering the parasitic capacitance of switching devices. A method to measure the parasitic capacitance is also proposed. The validity of the derived equivalent circuit is confirmed by simulation and experimental results.
    Download PDF (1117K)
  • Shinji Hasegawa, Masatake Kawada, Takashi Semura, Shiro Matsumura, Ken ...
    2002 Volume 122 Issue 2 Pages 191-192
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    Considerable skill is needed to recognize handwriting sequence diagram. In this paper, we proposed auto recognition method of handwriting sequence diagram using correlation method.
    Download PDF (182K)
  • Makoto Saitou, Tosihisa Shimizu
    2002 Volume 122 Issue 2 Pages 193-194
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    A control method of single phase power active filter on d-q coordinate with Hilbert Transformer is presented in this letter. By using Hilbert transformer, the d-q components on single phase current and voltage can be obtained. Then, harmonic components can be derived from these d-q components instantaneously as well as three phase power active filter systems. The effectiveness of the proposed control method has been verified by the computer simulator and some significant characteristics are also shown in this letter.
    Download PDF (179K)
  • Yue Lu Feng, Mutsuo Nakaoka
    2002 Volume 122 Issue 2 Pages 195-196
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    This paper presents an inductor snubber -assisted high frequency series resonant inverter for induction eddy current-heated roller in copy and printing machines, which can achieve ZCS and wide power regulation under constant frequency pulse density modulation. Its operating principle is presented, together with its output power regulation characteristics.
    Download PDF (193K)
  • Masaaki SHIBATA, Go TASAKI, Takeshi NATORI
    2002 Volume 122 Issue 2 Pages 197-198
    Published: February 01, 2002
    Released: December 19, 2008
    JOURNALS FREE ACCESS
    The paper reports a structural approach to reduce impact force in landing the swinging leg of biped robot. The robot introduces redundant legs in the sagital plane, which have redundancy in terms of DOF that is, extra joints besides hip, knee and ankle in each leg. The leg independently changes the posture, regardless of the tip position, while the center of mass (COM) of the leg moves to an arbitrary position even if the tip is fixed. Since the position of COM moves in landing the swinging leg toward the ground, therefore the impact force is reduced. The validity of the proposed approach is confirmed in physical experiments.
    Download PDF (1139K)
feedback
Top