In the Yamanashi Maglev (magnetic levitation) Test Line, running tests commenced on 3 April 1997, and have progressed well. The world record 552km/h run of manned 5-car unit was attained on 14 April 1999. “Reliability verification tests” are being planned for fiscal 2000. Tests that will include running tests at 500km/h, the target maximum speed for operational lines, will be repeated to verify reliability and durability. Concerning to LSM-drive-control, driving control system has performed well from high speed over 500km/h to stopping. For remarkable example, the Maglev train can be stopped within the deviation of 2.5cm errors. One of the important functions of running control for operational lines is minute-distance control called “Inching control”. When the deviation of stooping is beyond allowable errors, we have to correct stopping location of train with the Inching control accurately and quickly.
In this paper, we propose the Inching control method. Firstly we explain the flow and running pattern of inching control. Secondly we propose the inching control loop. Inching control comprises 3 main control loops, feed-forward loop of disturbance compensation, feedback loop of PID location control and two-out-of-three power feeding control. Finally we verify the effectiveness of the Inching control by experimental results of 10cm inching.

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Novel algorithm of the dynamic driving/braking force distribution is proposed for electric vehicle (EV) with four in-wheel motors. In such EV, the vehicle lateral motion can be controlled by yaw moment, generated with torque difference between wheels. This method is known as DYC (Direct Yaw moment Control) in normal engine vehicle engineering, however, the torque difference can be generated more directly with in-wheel motors. One problem of DYC is its instability on the slippery road, such as wet or snowy asphalt. To achieve high stability, the loads of wheels are preferable to be equal. The load of each wheel can be evaluated with root sum square of driving/braking force and side force. Therefore, the driving/braking forces, or motor torques, should be distributed depending on the side forces of wheels, to minimize the load imbalance between the wheels. The proposed algorithm can solve this optimization problem approximately with a few calculation cost, thus this method can be applied for real-time calculation within a control period. The approximate solutions with proposed method are evaluated by comparison with numerical solutions that require long calculation time. Difference between these solutions is negligible one, and this indicates the effectiveness of proposed method.

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This paper presents the fundamental study on the characteristics of motor using equivalent circuits representative of the magnetic properties of core materials, which can be used in the case of magnetic saturation or PWM. The iron losses were separated into those of field excitation and armature current one. The copper losses were also separated into parts related to output power, motor structural factors or magnetic saturation. The effect of manufacturing stress can be estimated and the punched core with thicker steel sheet and narrower width of tooth or yoke may have almost twice larger iron losses than steel sheets without manufacturing stress.

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The optimal H₂ control of oscillatory systems via the constraints of the derivatives of state variables is discussed and applied to a physical system in this paper. It is shown that the derivative state constrained optimal H₂ control can be reduced into the standard optimal H₂ control problem with modified controlled output equations. The solution to the modified standard problem has salient features for controlling oscillatory systems that have been a tough subject in state space as well as in classical frequency domain controls.
The results obtained in the paper suggest the directions how to select the constraining weights in the standard state space control designs of oscillatory systems.
The application of this approach to the control of a two-inertia resonance system is shown to demonstrate the proposed schemes.

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We have developed a local Conformance Test System (CTS) of Home Bus System (HBS) for the last many years. This paper presents a method to expand this as a remote CTS for layers 3 and 7 of HBS standards. We describe a constitution method of HBS/ISDN gateway in which the distant two HBS terminals can communicate mutually through ISDN without violating the traditional HBS standards. In addition, the definition formats of test suites and test cases that are required for the remote conformance test are introduced by using an examples of layer 7 of HBS. In order to inspect the effectiveness of our propsal, we provide the system construction of HBS and ISDN, mutual communication procedure of gateway, and an example of testing results of layer 7.

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Non-Contact Energy Transfer Systems are widely used in industrial material handling systems. This paper proposes a new Non-Contact Energy Transfer System using a tuned pick-up coil and an Immittance converter inductively coupled to a parallel transmission line excited by a high frequency constant current source.
In a Non-Contact Energy Transfer System which supplies continuous energy to movers by electromagnetic induction, the efficiency is low owing to low excitation impedance because of the wide air gap of the magnetic core in the pick-up coil. The excitation impedance can be increased by the resonance with a capacitor connected parallel to the pick-up coil. The resonant pick-up coil works as a high frequency constant current source for the load. We propose using an Immittance converter to transform the high frequency constant current source into a high frequency constant voltage source. Then, the high frequency constant voltage source is rectified into a constant voltage DC source, and supplies power to an inverter for motor driving.
In this paper, the configuration of this new Non-Contact Energy Transfer System and its characteristics are described. The experimental results and simulation waveforms are also described.

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Switched Reluctance Motors (SRM) have more simple and rugged construction compared to those of the conventional ac motors. Hence, SRM are suitable for low-cost variable-speed drives in many industrial applications. However, the need of a traditional position sensor for its control is one of the demerits of SRM from standpoints of cost, size and reliability. For practical use, the sensorless drive of SRM are expected.
This paper presents the position sensorless control of SRM based on a simple expression of non-linear magnetization characteristics. Successful experiments using 1.5kW, 5, 400rpm SRM with 6/4 poles configuration have been performed for verifying the practicability of the proposed sensorless control scheme.

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Consideration of passengers' transfer behavior is an important factor in railway service design. This paper proposes a new method for constructing railway network timetables in order to reduce transfer time. Firstly, an estimation method of the number of transfer passengers is proposed on the basis of a passenger behavior assumption of minimum travel time. Secondly, construction of railway network timetable is formulated as a nonlinear optimization problem. Thirdly, a genetic algorithm has been applied to solve the optimization problem, because its size for a practical problem is very large in terms of the number of variables. Finally, the effectiveness of the proposed method has been verified through typical examples.

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Reduction of the noise emitted from the automobile alternator has recently become a serious issue, and tangible especially concerning with improvement of the engine noise. In order to design a quiet automobile alternator, a designer needs to anticipate all important resonant frequencies. We simulated the electromagnetic vibration behavior of the rotor using experimental modal analysis and finite element method analysis. The results obtained are applicable to alternator design for reduction.

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In this paper, a new brushless synchronous condenser termed the BSC-Filter is presented. It consists of two wound-rotor induction machines connected in a cascade, and acts not only as a synchronous condenser but also as a passive filter with a capacitor connected to its stator field winding. An equivalent circuit model seen from the 6th harmonic in the field system is illustrated using the method of symmetrical coordinates. Based on this equivalent circuit model, a fundamental formula is derived to select the capacitor value properly. The validity of the theoretical analysis is verified through experiments, and basic characteristics of the BSC-Filter are clarified. In addition to phase compensation, this new machine is capable of reducing low-order 5th and 7th harmonics in power lines.

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Greater efficiency for electric vehicle motors is demanded nowadays. Significantly, higher efficiency of permanent magnetic type synchronous motor is possible, particulary for the IPM(interior permanent magnetic type) synchronous motor which has great mechanical strength and high efficiency because it uses the reluctance torque efficiently. However, the IPM motor's are influenced by not only induced voltage harmonic but also cogging torque. This paper describes the examinations of magnetic form for the IPM motor. The IPM moter's of trapezoid magnet form with gap have proved characteristics of the induced voltage sinewave form and high efficiency and low cogging torque.

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Coal fuel as one of the major fuel for the thermal power plants should be used to be effectively and environmentally accepted in the future. Integrated Coal Gasification Combined Cycle (IGCC) is expected to be the most suitable power generation system for this purpose and now being developed and commissioned in the world.
Viewed from the perspective of the power generation mixture in Japan, nuclear power plants will continue to be operated to meet the base load, while thermal power plants will be required to serve to cover the middle load. Therefore, IGCC plants will need to have a capability of following a wide range of load demand at high speed. For this purpose, a Load and Pressure Controller was developed and tested during the operational research on a 200 tons/day entrained flow IGCC pilot plant at the Nakoso Power Station by the Engineering Research Association for IGCC Power Systems (IGC Association) under the trust of New Energy and Industrial Technology Organization (NEDO). This paper reports on the development of this controller and its actual test results, focusing on the controller design using the dynamic simulation study.

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Recently, high precision and fast response motor drive systems are increasingly used in many industrial applications. With the development of control theories and equipment, the system response has become faster and faster, while the stiffness has reduced due to miniaturization and weight reduction of the equipment. As the result, the system has to be treated as a resonance system in some cases, so that some effective control methods to suppress the vibration are proposed.
Based on the pole placement approach, we have proposed a vibration suppression control method of the 2-inertia speed and position control systems which need no information about the load side variables. However, this method needs a lot of computation and the characteristic equation for the system must be changed according to the change of the inertia ratio. In this paper, we apply a genetic algorithm (GA) for the determination of the controller gains. Simulation results reveal that the proposed method is even useful for wide range of the inertia ratio and can get the solution quickly.
Finally, the effectiveness of the proposed method has been verified by experiments.

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The end effect of a linear induction motor (LIM) has been analyzed mainly by two methods which are based on the Fourier series method, that is, the space harmonic method and the Fourier transform method respectively.
The space harmonic analysis has been carried out firstly by the author, which is suitable for numerical calculation taken directly into account of design parameters of LIM, such as the primary winding arrangement and the construction of the secondary reaction rail.
But, it was very difficult and complicated to do calculation by using the Fourier transform method taking into account the design parameters of LIM in detail.
In the paper, a simplified Fourier transform method based on the space harmonic method is described. The summation in the space harmonic method is converted the Fourier integral in the region of effective pole pitches around the real pole pitch of LIM.

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A power factor corrected (PFC) boost converter with discontinuous current mode (DCM) operation can decrease the total harmonic distortion with simple circuit and easy control method. However, the PFC converter must be tumed off at maximum inductor current and the distortion in the input current increases with low ratio of output voltage to input voltage. To reduce the switching losses and EMI noise, a soft switching circuit for the PFC converter is proposed in this paper. A simple control method to improve the input current waveform in low ratio of output voltage to input voltage is suggested for practical use.

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