Mi-Ching Tsai

National Cheng Kung University, 臺南市, Taiwan, Taiwan

Are you Mi-Ching Tsai?

Claim your profile

Publications (89)88.06 Total impact

  • I-Hsien Lin · Min-Fu Hsieh · Hsiu-Fu Kuo · Mi-Ching Tsai ·
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper develops an approach that is capable of accurately predicting the performance of synchronous reluctance motors (SynRMs). The SynRMs receive increasing attention and have been used in many industrial applications. The 2-D finite element analysis (FEA) is usually considered to be competent for design and analysis of SynRMs. However, the power factor of SynRMs is likely to be considerably overestimated. This would then lead to an underestimation of current required and cause problems for the design of electronic drivers. Compensation should be made to improve the accuracy of the analysis for SynRMs although there does not seem to be a solution put forward so far. The research in this paper shows that the exclusion of end turn leakage inductances in 2-D analysis is a key factor to cause such a significant difference. To resolve this problem, this paper analytically calculates the end turn leakage inductance, which is then incorporated into the 2-D FEA. The developed method is found to agree well with the experimental results, and it significantly improves the design accuracy and efficiency using only the 2-D FEA.
    IEEE Transactions on Magnetics 11/2015; 51(11):1-1. DOI:10.1109/TMAG.2015.2450255 · 1.39 Impact Factor
  • Chao-Chien Chiang · Min-Fu Hsieh · Yu-Hsien Li · MI-CHING TSAI ·
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper develops an approach to evaluate and predict the effect of punching processes upon the performance of switched reluctance motors (SRMs). Punching is a common process for manufacturing of electric motors although the magnetic performance of the electrical steels at the cut edges may degrade. This could then result in a lower motor performance than expected. Annealing can usually restore the material property but it would be costly for production of common electric motors. Therefore, it is useful to compensate this effect in the design of electric motors. In this paper, the damaged range due to punching is modeled and included in the finite-element simulation for the SRMs such that the effect of this damage can be evaluated. The material properties at the cut edges are determined using the techniques developed here. Two SRMs are investigated: one being annealed after punching and the other not before assembly. Test results show that the annealed SRM produces a better performance. The comparison between the simulations and experiments shows that the developed method can be used for analysis of punching effect on motor performance.
    IEEE Transactions on Magnetics 11/2015; 51(11):1-1. DOI:10.1109/TMAG.2015.2449661 · 1.39 Impact Factor
  • Po-Wei Huang · Mi-Ching Tsai ·
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents the design of a new flux switching device that is capable of coupling with surface permanent magnet motors to become a new actuator featured with auto-locking, increased safety, and higher energy utilization. These advantages are based on the concept of flux switching and the alternation of electric power with cogging torque. In this design, four additional axial winding coils are proposed to smoothing the switching process and provide bi-directional rotation. In addition, different manufacturing processes of the inner rotor are discussed with the aim of simplifying the fabrication process. The torque characteristics are investigated experimentally and analytically using a prototype and finite element analysis tool, respectively.
    IEEE Transactions on Magnetics 07/2015; 51(11):1-1. DOI:10.1109/TMAG.2015.2438300 · 1.39 Impact Factor
  • Mi-Ching Tsai · Kwei-Yuan Chiou · Sheng-He Wang · Ching-Kuo Lin ·
    [Show abstract] [Hide abstract]
    ABSTRACT: Torque-speed characteristics measurements are essential in the design and manufacture of electric motors. Dynamometers have been widely used in motor characteristics measurements, and the coupling between the motor under test and dynamometer is a critical issue for high-power electric motors. This paper develops a contactless measurement system, which consists of a permanent magnet (PM) coupler and requires no dynamometer. The torque of the PM coupler is transmitted by the eddy-current and controlled by the air gap inside the coupler. An equivalent circuit model of the magnetic coupler is derived theoretically and then verified experimentally under different operating conditions. The capacity of the proposed measurement system can also be determined in order to provide sufficient and accurate measurement information for the tested motors. A 1.5 kW dc motor with a maximum torque of 8.15 N-m was tested as an illustrated example. The experimental results are given to show the effectiveness of the proposed approach.
    IEEE Transactions on Magnetics 11/2014; 50(11):1-4. DOI:10.1109/TMAG.2014.2332536 · 1.39 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper compares the microstructure and magnetic properties of punched electrical steel before and after annealing. The effects of this manufacturing process on performance of a switched reluctance motor (SRM) are also investigated. The punching of laminations distorts the grains near the cut edges, and therefore an anneal process is used to recover the damage caused by punching. In this paper, samples are annealed at 750°C for an hour under a N2 atmosphere. The damaged regions and corresponding recovery after annealing are observed under microscope as the measured core losses are improved up to 37%. The SRM performance is measured and it is found that the torque density can be enhanced when using the annealed electrical steel.
    IEEE Transactions on Magnetics 11/2014; 50(11):1-4. DOI:10.1109/TMAG.2014.2329708 · 1.39 Impact Factor

  • 09/2014; 3(3):256-263. DOI:10.11142/jicems.2014.3.3.256
  • Wei-Hsiu Tai · Mi-Ching Tsai · Zwe-Lee Gaing · Po-Wei Huang · Yu-Sheng Hsu ·
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents a novel double salient motor design in which the permanent magnets are implanted in the stator to provide additional magnetic flux sources for enhancing its performance and reducing the inherent cogging torque. The feasible cones method is adopted to calculate the dimensional sizes of the proposed short flux path motor. The assembled stators concept is employed to design the magnetic flux paths of the double salient permanent magnet (DSPM) motor and also transfer the heat generated by the windings outside the motor. Due to the nonlinear properties of the doubly salient structure, this paper utilizes both magnetic circuit analysis and finite element analysis to evaluate different operating characteristics of the designed DSPM motor. Experimental data are provided to verify the proposed design.
    IEEE Transactions on Magnetics 04/2014; 50(4):1-4. DOI:10.1109/TMAG.2013.2283373 · 1.39 Impact Factor
  • Mi-Ching Tsai · Po-Wen Hsueh ·
    [Show abstract] [Hide abstract]
    ABSTRACT: Wheelchairs used by disabled people or caregivers are typical human-in-the-loop systems, of which the power-assisted control in accordance to a human’s perception is essential. This paper presents a force sensorless control based on a force/torque observer with a motion coordinate transformation for power-assisted wheelchairs. The output linear movement and angular velocity motions of a power wheelchair can be controlled independently by inherent coupling dual-driving-wheels with this transformation. A force observer design without numerical differentiation, which is utilized to indirectly measure the human’s pushing force, is proposed for realizing the force sensorless power-assisted control. An assistant performance index is adopted to evaluate the validity of the power-assisted control according to a specified power-assisted gain. Experimental results show that the proposed method can effectively estimate the human force exerted on the wheelchair for achieving power-assisted control.
    Mechatronics 12/2013; 23(8):1014–1024. DOI:10.1016/j.mechatronics.2013.07.010 · 1.73 Impact Factor
  • Po-Wen Hsueh · Jyun-Ci Chen · Wu-Sung Yao · Mi-Ching Tsai · Wei-Cheng Syu ·
    [Show abstract] [Hide abstract]
    ABSTRACT: Haptic technique is a tactile feedback skill between humans and machine devices. How to deal with the compliantly controlled haptic interaction is essential. This paper proposes an impedance control design based on Luenberger observer for haptic linear servo motors. With the consideration of practical implementations, the Luenberger observer is substituted for tactile sensors to estimate the external force exerted by humans. The controlled motion looks like a spring-mass-damper system required by the desired haptic system and realized by the proposed impedance control. Simulation and experimental results are given to show that the dynamic behavior of the controlled linear servo motor is analog to a desired spring-mass-damper system.
    2013 CACS International Automatic Control Conference (CACS); 12/2013
  • Po-Wen Hsueh · Mi-Ching Tsai ·
    [Show abstract] [Hide abstract]
    ABSTRACT: The lower limb cycle ergometer driven by a motor is a typical rehabilitation-assistive device for hemiparetic patients with abnormal muscle tone in their lower limbs. Since unusual muscle tone may cause excessive spasticity during rehabilitation, it is important to monitor reactive torques produced primarily by the abnormal muscle tone. Thus, this study investigated a state observer design applied to a belt-driven ergometer, where the motor current and position information were used to estimate reliable reactive torque. A dual feedback control loop was proposed to improve the resonance caused by the belt-driven structure and stabilize the cycling speed in the cycle rehabilitated device; meanwhile, the impedance model constructed by the feedback control loop is presented to generate the compliance characteristic for stably and gently controlling the speed response affected by reactive torque. Simulation and experiments of the belt-driven ergometer were conducted with results validating the effectiveness of the proposed control scheme in terms of stable cycle speed and observer performance. Crown Copyright
    Control Engineering Practice 11/2013; 21(11):1564-1576. DOI:10.1016/j.conengprac.2013.07.002 · 1.81 Impact Factor
  • Wu-Sung Yao · Mi-Ching Tsai · Yutaka Yamamoto ·
    [Show abstract] [Hide abstract]
    ABSTRACT: Time-varying periodic motions have appeared in many industrial processes, such as cam-follower systems, in that the control system has to operate at a periodic variable velocity specified in terms of the angular position-domain. This paper employs a repetitive control for rejecting the time-varying periodic disturbances, and presents an implementation technique based on angular position which can generate a fixed number of cycles in real-time. This control technique can accommodate the period variation in a time-varying periodic signal such that variable samples per period for synchronization can be achieved by the regular fixed-time sampling rate. A technique using position information to manipulate the delayed data and an interpolation scheme to properly access data in the buffer memory is proposed. An anti-vibration control system with time-varying periodic disturbances is studied to illustrate control performance. The experimental results are given to illustrate that time-varying repetitive control can effectively eliminate steady-state errors within a few cycles.
    Control Engineering Practice 09/2013; 21(9):1226–1237. DOI:10.1016/j.conengprac.2013.04.010 · 1.81 Impact Factor
  • Sheng-He Wang · Mi-Ching Tsai ·
    [Show abstract] [Hide abstract]
    ABSTRACT: Noncontact tweezers using acoustic levitation technology are useful for microhandling processes as they have fewer restrictions with materials or particle shapes. This has significant value in the development of composite materials and biotech industries where the contamination is an issue, such as the production of advanced microbiochips for health diagnostics. This involves the mixing of multiple components in a stable suspension of drops without a container. In this paper, a quasi-standing wave field generated by crossing two ultrasonic waves from piezoelectric transducers is adopted to develop acoustic tweezers. Compared with general single-axis acoustic levitation, the proposed acoustic tweezers can levitate small particles at pressure nodes without the need for a reflector and has the capability of 2-D movement. Additionally, a theoretical model of the proposed acoustic tweezers is derived such that the pressure distribution of the tweezers can be calculated from the operating conditions to determine the trapped position. With a 10° inclination and frequency of 27.6 kHz, a 400 Pa levitated pressure can be generated to float polystyrene spheres with a density of 16.37 kg/m3, and a 2 mm × 3 mm movement of the trapped position is demonstrated by adjusting the relative orientation and the relative distance of the two transducers, respectively. The simulation and experimental results demonstrate the effectiveness of the proposed acoustic tweezers' model to predict particle trapping.
    IEEE/ASME Transactions on Mechatronics 06/2013; 18(3):1019-1026. DOI:10.1109/TMECH.2012.2195191 · 3.43 Impact Factor
  • Po-Wei Huang · Mi-Ching Tsai ·
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents an investigation into the effect of the reactance on a V-shaped line start permanent magnet motor. Five rotor designs with different V-shaped angles are utilized for exploring motor characteristics with the reactance. Performances such as back electromotive force, d- and q-axis reactance, loading capability and efficiency are simulated and analyzed by the torque model and a time stepped two-dimensional finite element software application. According to the comparison, the variations of output behaviors with d- and q-axis reactance can be described. Moreover, the design which features both excellent synchronization capability and high efficiency was verified by experiment on a prototype.
    IEEE Transactions on Magnetics 05/2013; 49(5):2311-2314. DOI:10.1109/TMAG.2013.2239279 · 1.39 Impact Factor
  • Jyun-Ci Chen · Po-Wen Hsueh · Mi-Ching Tsai ·
    [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this study is to develop the control approach of a belt-driven cycling device for lower-limb rehabilitation by providing passive movement therapy training at a stable cycling speed. To achieve stable cycling speed, the speed controller design is based on a two-inertia system model, which is established for the cycling device incorporating the transmission belt. The proposed minimum complexity controller method features a speed control design employing acceleration information feedback to successfully reduce vibration. Simulations and experimental results are presented to validate the feasibility of the proposed control system.
  • [Show abstract] [Hide abstract]
    ABSTRACT: The ability to sustain a smooth-running practice is very important in dentistry. Because of this reason, Electric handpieces driven by permanent magnetic synchronous motors (PMSMs) have been increasingly applied in dentistry and have replaced air-driven ones due to their high efficiency and ability to sustain constant speed while operating. Additionally, they produce little noise compared to the high pitched whine of their air-driven counterparts. As is well known, the rotor position is the necessary information for driving a PMSM. Unfortunately, a dental handpiece requires repeated heat sterilization that will break down the Hall sensors, and further, lacks the space to install an incremental encoder. Therefore, sensorless speed control of a PMSM is the key technology for an electric dental handpiece. In this paper, a sliding mode observer is used to implement an electric dental handpiece. Moreover, a prototype of the electric handpiece system has been designed and built. Experimental results are presented to verify the feasibility.
    Industrial Electronics (ISIE), 2013 IEEE International Symposium on; 01/2013
  • [Show abstract] [Hide abstract]
    ABSTRACT: Torque ripple is a very essential index for evaluating the effectiveness of a switched reluctance motor (SRM). Many common design strategies for reducing torque ripples of a SRM are (i) changing the excitation trigger angle of stator windings, (ii) delaying the cut-off time of winding excitation, (iii) adjusting the ratio of the arc angle between the stator and rotor, and (iv) changing the geometric shape of the rotor. However, the output torque or the efficiency of the SRM may drop as the above design strategies are solely adopted. In this paper, a hybrid design model which is obtained by the Taguchi Method for optimally designing a SRM with lower torque ripple and higher efficiency is presented. An 8P12S motor is taken as a study case, and the 3D finite element method (FEM) is applied to analyze the characteristics of the motor and optimize the design process. The results show that the proposed method can achieve the design goal of obtaining a high-performance SRM for light electric vehicle applications.
    Electrical Machines and Systems (ICEMS), 2013 International Conference on; 01/2013
  • Chung-Hsien Lin · Mi-Ching Tsai · Shih-Wei Hsiao ·
    [Show abstract] [Hide abstract]
    ABSTRACT: The paper presents a static force measurement based on the characteristic of piezoelectric devices which are known as an electromechanical transducer. Material properties of a piezoelectric device vary with applied static forces and merge into the equivalent electrical admittance of the piezoelectric device through the electromechanical interaction such that the applied static force can be obtained by the equivalent electrical admittance variation. Differing from the general static force measurement by piezoelectric devices, we measure the static force by detecting magnitude and phase of the admittance at a fixed frequency. A prototype for achieving the static force measurement is built as a cantilever beam structure. Experiments are carried out for evaluating the performance of two detection methods, results of which show that the repeatability and hysteresis error are less than 12.0% of full scale output (FSO) and 7.5% FSO, respectively, by using the phase detection method. The proposed static force measurement can be embedded in automation assembly systems due to its simple structure, which is particularly suitable for use of gripping jaw applications.
    Sensors and Actuators A Physical 11/2012; 187:147–153. DOI:10.1016/j.sna.2012.09.001 · 1.90 Impact Factor
  • Po-Wei Huang · Mi-Ching Tsai ·
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents the design of an actuator with high efficiency and auto-locking ability which features an additional holding force in the power-off condition. The operating principle of the auto-locking structure is based on the concept of flux switching. In the paper, an analytical method for computing the cogging torque of the two operating states (the moving and holding states) is developed. It is investigated that the actuator develops a holding force in the power-off condition which can be safely turned on using the auto-locking mechanism The torque characteristics for the auto-locking structure are also investigated using analytical and finite element analysis methods (using ANSYS 3D FEA software). A prototype is constructed and the experimental results are used to verify and validate the simulation results.
    IEEE Transactions on Magnetics 11/2012; 48(11):4622-4625. DOI:10.1109/TMAG.2012.2204235 · 1.39 Impact Factor
  • Wu-Sung Yao · Mi-Ching Tsai · Jian-Zhi Lai · Fu-Yun Yang ·
    [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, a motion trajectory detecting method that permits tracking of magnetic objects is investigated by the magnetic flux density of a 3-D Hall probe. Inaccurate motion trajectory information may be produced physically due to the measured magnetic field signal altering as the distance between the Hall probe and the object changes. A magnetic flux feedback control is proposed such that the motion command of the control system is generated in real time by the coordinated geometry of the Hall probe and the magnetic object. The magnetic tracking control system consists of an inner position/velocity control loop and an outer magnetic control loop that employs a position vector expressed in terms of the magnetic flux density to detect the relative distance between a magnetic object and the Hall probe. The measurement of the Hall probe can, hence, be kept within an effective distance such that the motion trajectory of the measured magnetic object can be detected accurately for the case of large movements. An experimental setup with a five-axis servo mechanism is constructed for the validation study, in which the three-axis moving table is utilized to control the motion of the Hall probe, and the other two-axis moving table facilitates the movement of the magnetic object. A circular motion and a rhomboidal path are given to verify the improvement of the proposed detecting method.
    IEEE/ASME Transactions on Mechatronics 08/2012; 17(4):709-716. DOI:10.1109/TMECH.2011.2118226 · 3.43 Impact Factor
  • Mi-Ching Tsai · Cheng-Chi Huang ·
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper presents a mechanical device with controllable inertia, in which a magnetic planetary gearbox (PG) is employed to hold two free terminals (the carrier and sun gear) and one feedforward control terminal (the ring gear). Based on the concept of inerter design and impedance control, the ring-gear motor controls the equivalent inertia of the carrier. The sealless nature of the proposed noncontact magnetic PG provides a low-inertia design ability and an over-load protection characteristic for a high-torque transmission. The control block diagram technique is utilized to represent the dynamic model of the variable-inertia device for the equivalent-inertia derivation and computer simulation, in which its equivalent inertia can be found by the transfer function from the torque to the acceleration at the carrier. Finally, the dynamic model is verified by experiments, and the controlled range of the equivalent inertia is illustrated.
    IEEE/ASME Transactions on Mechatronics 01/2012; 16(6-16):1120 - 1128. DOI:10.1109/TMECH.2010.2077679 · 3.43 Impact Factor