A novel surface-mounted outer rotor transverse flux permanent-magnet motor (SMOR-TFPM) with simple structure and good performance is proposed in this paper. The basic structure and operating ...principle of the motor are introduced. According to the deficiency of the SMOR-TFPM electrical performance, this paper presents an improved design of the stator so that the motor performance is improved by transforming parts of the leakage flux into the main flux. The finite element model of the motor is established, the influence of the relevant parameters on the no-load magnetic leakage coefficient is optimally analyzed based on the three-dimensional finite element method. The main parameters design of a three-phase and fifteen-pair-pole SMOR-TFPM is completed based on the improved design and optimization analysis. The coupling relationship of the interphase magnetic field is verified. Besides, the motor torque characteristics are researched and analyzed. The results prove that the structure and dimensions design of the motor is reasonable and the characteristics are stable, which has a certain feasibility.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The effect of solar radiation on two typical external surfaces of a spacecraft is studied using numerical simulation by considering real geometry (geometry deviation from the nominal shape). The ...results of simulation are presented in this paper. Geometry deviations are simulated by two types of regular external heterogeneities. We compare the force and torque characteristics of solar radiation on nonuniform surfaces with similar characteristics for nominal surfaces and we find that the disagreement between them can reach 90% both in absolute value and sign. This means that it is necessary to consider the deviations in geometry from nominal for proper design and operation of spacecraft.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Three different radial flux ironless brushless dc (BLdc) motor types (motors without inner back-iron of the rotor, with inner back-iron of the rotor, and with dual-rotor) are investigated and ...compared in this paper. The magnetic field distribution, back electromagnetic force (EMF), axial end effect, and torque characteristics are investigated. First, the relationship between the magnetic field distribution and the motor size and pole pairs is investigated. It shows that the two parameters are not independent of each other and the magnetic field distribution is mainly related with the arc length of the permanent magnets. Second, the radial magnetic flux density in the coil regions of the three ironless BLdc motors is calculated and an evaluation factor is proposed to show the quality of the magnetic field distribution. Third, the influence of the winding configuration and the combination of slot and pole number on EMF is analyzed, and the corresponding evaluation factors are calculated and tabulated. Then, the axial end effect of the three ironless BLdc motors considering the fringe effect is investigated and compared. Next, the torque characteristics at full load and rated speed are studied for the three types of motors. Finally, the ironless BLdc motor without back-iron of the rotor is manufactured and tested. The experimental results are in good agreement with the finite-element method.
The permanent magnet (PM) is the key part of the relay. This paper aims to solve the problem of the uneven magnetization for the PM with nonlinear demagnetization curve after magnetizing and ...demagnetizing. A method partitioning the PM along the magnetization direction and the vertical direction of magnetization according to the condition of the specific magnetization of the PM was presented. By this method, the demagnetization model of the PM was built, the state of the PM magnetization was simulated under the demagnetizing magnetic intensity, and the recoil line and its initial point of each partition of the PM were obtained. Then the characteristic of the recoil line of each partition was used as its magnetic characteristic for the equivalent model of the PM to calculate the static torque characteristics under the demagnetizing magnetic field. Finally, the static torque characteristics of simulation and experiment were compared and the validity of the equivalent model presented was verified.
The friction coefficient between the vane and the slot is one of the most critical factors that affects the performance of a continuous rotary hydraulic cam-rotor vane motor. To study the effects of ...this coefficient on the torque characteristics of the motor, the mathematical model for the normal force and the disturbing torque between the cam rotors and the vanes of the motor was established by analyzing the forces exerted on the vanes. The mathematical model was simulated with MATLAB, and simulation results show that an increase in the friction coefficient would simultaneously decrease the normal force and increase the disturbing torque, which would negatively affect the performance of the motor. Further experimental research indicated that the low-speed performance of the hydraulic cam-rotor motor was significantly improved when the friction coefficient was reduced by controlling the parallelism tolerance, flatness and roughness between the vanes and the slots.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This paper provides essential information on the development of a 'dc motor test and analysis control card' using AVR series ATMega32 microcontroller. This card can be interfaced to PC and calculates ...parameters like motor losses, efficiency and plot characteristics for dc motors. Presently, there are different tests and methods available to evaluate motor parameters, but a single and universal user-friendly automated set-up has been discussed in this paper. It has been accomplished by designing a data acquisition and SCR bridge firing hardware based on AVR ATMega32 microcontroller. This hardware has the capability to drive the phase-controlled rectifiers and acquire real-time values of current, voltage, temperature and speed of motor. Various analyses feasible with the designed hardware are of immense importance for dc motor manufacturers and quality-sensitive users. Authors, through this paper aim to provide details of this AVR-based hardware which can be used for dc motor parameter analysis and also for motor control applications.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
This paper presents the detailed process of design and implementation of the transmission systems and mo-tor poles in electric vehicles (E-Vehicle). It involves the designing of motor poles, ...optimizing torque delivery, and ensuring seamless power transfer between the motor and wheels. This study investigates the critical role of pole count in designing BLDC motors specifically optimized for EV performance. We explore the impact of pole count on crucial motor characteristics, including speed, torque, and overall motor size. The analysis addresses that the fewer poles deliver high torque but result in a larger motor, while more poles yield higher speeds at the expense of torque. This investigation incorporates factors spe-cific to EVs, such as desired speed range, torque requirements, and size/weight limitations, to guide optimal pole count selection. Finally, the paper concludes by outlining implementation strategies for integrating the chosen pole design into BLDC motors for successful application in electric vehicles. Ultimately, this article represents the necessary ideas for the implementation of the design model in BLDC motors, thus paving the way for their integration into electric vehicles. Combining different aspects of analysis and practical application, this research helps to improve the performance of electric drive systems, thereby Solving transportation problems.
This study investigates the influence of machine design parameters, mainly the mutual and leakage inductances, on the flux-weakening performance of induction machines (IMs) for electrical vehicle ...application. In addition, the influences of other practical issues, such as iron saturation, stator and rotor resistances and so on, are investigated. A per-unit model is employed for the investigation, while during the analysis, the inductance ratio between the leakage and mutual inductance is introduced. It is shown that, in general, it is very difficult to achieve infinite flux weakening performance of IMs, and only with ideal zero inductance ratio, could IM achieve infinite constant power region and the maximum utilisation of inverter. Finally, analytically calculated torque/power-speed characteristics of a 12 kW IM are verified by finite element analyses and experiments.
The objective of this study is to develop a new spiral spring that exhibits unique deformation behavior. The properties of the spiral spring make it suitable for use not only as an energy storage ...element but also as an actuator or similar device. In the present study, a process for manufacturing a spiral spring made of Ti-Ni superelastic alloy wires was proposed. In addition, torque characteristics of the manufactured spiral spring were investigated by torque measurement tests. Rotational torque during wind and rewind processes at a constant rotational speed was monitored. In addition, torque measurement tests were repeated to investigate the effect of the number of wind and rewind processes on the torque characteristics. Two main results were obtained. First, the torque characteristics of the spiral spring show torque plateau behaviors, which are expected to produce a constant energy output. Second, the torque characteristic depends on the number of torque measurement tests. Torque values decrease with increasing number of repeated tests. These results for the spiral spring correspond to the superelastic behavior of the Ti-Ni alloy.
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