Output Power Of Motor Research Articles

Analisis Pengaruh Sudut Penyalaan TRIAC terhadap Pengaturan Kecepatan Motor Induksi Satu Fasa Menggunakan Cycloconverter

ABSTRACTA single-phase induction motor is one type of electric motor that is most widely used in everyday’s life, especially for running small loads. The application of this single phase induction motor is not only in households but also in shops, shopping centers, and industry. In its operation, single-phase induction motors can be operated with constant speed and variable speed. The operation of a single-phase induction motor at a constant speed can be done by inputting the nominal voltage and frequency of the motor. Meanwhile, the operation of a single-phase induction motor with varying speeds can be done by adjusting the input frequency of the motor. In this study, an induction motor speed control was carried out using a cycloconverter to regulate the speed of a single-phase induction motor by changing the input frequency of the motor into three variations, namely f / 1, f / 2 and f / 3 at the base frequency of 50 Hz. The cycloconverter switching was designed using TRIAC and then a study was carried out on the effect of the TRIAC’s firing angle on the speed, voltage and output power of the motor by varying firing angles by 0?, 30?, 45?, 60? and 90?. The result show, it is found that increasing the firing angle, the motor output voltage decrease, the motor output power also decrease, except at the angle of 60 ? rises then at the angle of 90 decrease again, while the motor speed increases at the same frequency. Keyword: cycloconverter, firing angle, TRIAC.

Effects of power take-off parameters and harvester shape on wave energy extraction and output of a hydraulic conversion system

Considering nonlinear hydrodynamic forces of a harvester in irregular waves and a nonlinear hydraulic power take-off system, a time-domain nonlinear motion model and nonlinear hydraulic power take-off models are established to investigate the harvester motion response, the hydraulic system dynamic performance, the power extraction, the motor output power and efficiency. Matlab/Simulink is used to establish and simulate the system models. The convolution identification of nonlinear radiation force is based on a state-space model. The parameters of the state-space model and the infinity frequency added mass are fitted based on the least square method. The nonlinear hydrostatic storing force is considered for cone and hemisphere. The Pierson–Moskowitz 2-parameter spectrum is adopted for the irregular waves. The Coulomb friction force and viscous friction force based on the pressure difference and hydraulic cylinder parameters are modeled in the power take-off force. Under a given sea state, for cone, cylinder and hemisphere, the optimal hydraulic power take-off parameters are predicted based on a genetic algorithm for the maximum motor output power. The effects of the hydraulic cylinder piston working area, the motor displacement, the high pressure accumulator pre-charge pressure and initial volume, the significant wave height and energy period, the harvester diameter, draft and shape on the extracted power, the extraction efficiency, the motor output power and the hydraulic conversion efficiency are investigated. The extraction ability of the cone harvester is the highest among three shapes under the same diameter and draft. The conversion efficiency increases as the motor displacement decreases.

Motion coordination for humanoid jumping using maximized joint power

Jumping capability of humanoid robots can be considered as one of the cruxes to improve the performance of future humanoid robot applications. This paper presents an optimization method on a three-linkage system to achieve a jumping behavior, which is followed by the clarification of the mathematical modeling and motor-joint model with practical factors considered. In consideration of the constraints of ZMP and the performance of the motor, the output power of the joint motors is maximized as much as possible to achieve a higher height. Finally, the optimization method is verified by the simulation and experiment. Different from other electric driven robots, which take the output power of the joint as the constraint, we maximize the output power of the joint to optimize the hopping performance of the robot. Realizing dynamic jumping of humanoid robots can also provide a solid foundation for further research on running, which can greatly enhance the environmental adaptability.

Electromagnetic Field Analysis and Design of a Hermetic Interior Permanent Magnet Synchronous Motor with Helical-Grooved Self-Cooling Case for Unmanned Aerial Vehicles

As unmanned aerial vehicles expand their utilization and coverage, research is in progress to develop low-weight and high-performance motors to efficiently carry out various missions. An electromagnetic field interior permanent magnet (IPM) motor was designed and analyzed in this study that improved the flight performance and flight duration of an unmanned aerial vehicle (UAV). The output power and efficiency of a conventional commercial UAV motor were improved by designing an IPM motor of the same size, providing high power output and high-speed operation by securing high power density, wide speed range, and mechanical stiffness. The cooling performance and efficiency of the drive motor were improved without requiring a separate power source for cooling by introducing the helical-grooved self-cooling case, which has a low heat generation structure. Furthermore, the motor is oil-cooled through rotating power without a separate power source, reducing the weight of the UAV. The heat dissipation characteristics were verified by fabricating a prototype and taking actual measurements to verify the validity of the heat dissipation characteristics. The results of this study are expected to improve the flight duration and performance of UAVs and contribute to the efficiency of the design of a UAV drive motor.

Energy saving by reducing motor rating of sucker-rod pump systems

Energy industry can make significant savings by reducing electric motors ratings of the popular Sucker-Rod Pump (SRP) systems. This can be achieved by application of robust controllers, which are fully integrated with the SRP systems. In this work we have developed, modelled and analysed such integrated systems, specifically by examining two control schemes with open- and closed-loop controllers. The open loop scheme employs a genetic algorithm optimizing frequency in order to minimize fluctuations in a motor output power. This approach results in reducing the peak torque and consequently decreases the required motor rating by 20%. However, the scheme relies on a complex model of this electromechanical system, and it is computationally expensive. The second proposed scheme with a closed-loop control, the first of its kind for the SRP systems, is much faster and robust. It allows to reduce the motor rating by further 30% of that required in the open-loop scheme, which can save $246 M through choosing smaller motors and $39 M per year by reducing motor inner loss.

Магнитное поле и силы в гибридной системе левитации высокоскоростного транспорта

A hybrid system designed to provide levitation for a high-speed on-ground vehicle at low traveling speeds is considered. The levitation is obtained due to the simultaneous use of electrodynamic repulsion forces and electromagnetic attraction forces. Structurally, this is implemented by using two longitudinal tracks. One of them, which is electrically conducting and nonmagnetic, is located under the vehicle excitation solenoid, and the second one, which is ferromagnetic, is arranged above the vehicle excitation solenoid only on the acceleration, braking and station sections. To ensure the equality of the resulting levitation force to the vehicle weight on all of these motion sections, the ferromagnetic track is made so that its area that participates in producing the attraction force varies depending on the vehicle motion speed. To avoid the negative effect of eddy currents induced in the ferromagnetic track, the latter is made of plates electrically insulated from each other. In performing the design calculations, the tracks were represented as plates of infinite size. An analytical solution for the magnetic field and levitation forces is obtained. It is shown that in particular cases, the results obtained from these solutions coincide with the results obtained previously by other authors for the conventional repulsion levitation system. The possibility of levitation at low speeds and stops is confirmed, and it is pointed out that a somewhat growth in the braking force does not has an essential influence on the traction linear motor power output

System‐level optimal design process of inverter‐fed BLAC motor used for 12–48 V integrated electric brake system

In this study, to maximise the performance and efficiency of 48 V integrated electric brake (IEB) system, a system-level optimal design process is proposed for inverter-driven brushless AC (BLAC) motor, taking into account the available input voltage that varies depending on the motor operating conditions. To get available input voltages, the voltage drops of battery wiring and inverter are reversely calculated from the motor output power. In the optimal design process, the resistance components in the inverter are separated into DC and AC parts, and these are analysed by including the dq equivalent circuit for motor analysis. The battery currents are obtained using the calculated maximum output performance and the loss between the battery and inverter. The proposed design process is applied to the optimal design of the 48 V motor for IEB systems. Also, to reduce the development cost of the 48 V motor, the manufacturing tools of the previously developed 12 V motor are shared. As an optimal design results, it is confirmed that there is an efficiency improvement effect of ∼5% compared to the conventional design of 12–48 V BLAC motor.

A Dumbbell Shaped Piezoelectric Motor Driven by the First-Order Torsional and the First-Order Flexural Vibrations

A piezoelectric motor driven by the first-order torsional and first-order flexural (T/F) vibrations is designed, fabricated, and tested in this study. The actuating force is generated by the torsional vibration of the dumbbell-shaped vibrator, while the elliptical motion shape is adjusted with the flexural vibration. The rotor, pressed onto the vibrator’s lateral surface, is frictionally driven with the vibrator. Here, the torsional vibration, the shear modes of piezoelectric ceramics, and the driving method may contribute to high torque and high output power. To test the feasibility of our proposal, first, a prototype of the T/F vibrator is built and its vibration properties are explored. As predicted, the torsional and flexural vibrations are excited on the vibrator. Then, the load characteristics of the piezoelectric motor are investigated. The maximal torque, the no-load rotation speed, and maximal output power are 4.3 Nm, 125 r/min, and 16.9 W, respectively. The results imply that using the first-order torsional and the first-order flexural vibrations is a feasible method to achieve high torque and high output power of piezoelectric motors.

Research on Constant Power Control Strategy of Pure Electric Excavator

Electric construction machinery can achieve zero emissions and be pollution free in the process of construction. In an electric excavator, to make full use of the output power of the power source, the output power of the electric motor (EM) should be absorbed by a hydraulic pump on the most attainable level. Therefore, constant power control is generally employed to achieve power matching between the power source and hydraulic pump. In this paper, considering the shortcomings of a single constant power point in a traditional load sensing system of electric construction machinery, combining the discharge characteristics of the li-ion battery and the overload capability of EM, a piecewise constant power control strategy is proposed to realize the organic unity of power and safety for a novel electric construction machinery power train system. The control strategy is verified by simulations and experiments. The results show that the system can not only satisfy the large power output but also ensure the normal and stable operation of the system when the electric excavator meets the heavy load through the piecewise constant power control. The proposed control strategy improves the dynamic performance of the system on the basis of ensuring the safety of the system.

Thermal analysis of the triple-phase asynchronous motor-reducer coupling system by thermal network method

As the core components of mechanical power system, triple-phase asynchronous motor and reducer are required strictly for temperature control. In this paper, the triple-phase asynchronous motor and the reducer are regarded as a coupling system, and thermal network method is used to predict the temperature field distribution of the coupling system. The predicted temperature of the thermal network method is consistent with the experimental result and the finite-element analysis. Furthermore, analysis shows that motor output power, coefficient of friction between teeth and lubricating oil parameters have a great effect on reducing the temperature of the coupling system.

A method for selecting parameters of the electromechanical transmission of an industrial tractor

The article describes a method for selecting the torque — speed characteristics of the drive motors and parameters of the electromechanical transmission of an industrial tractor. In order to provide the maximum performance of the tractor the transmission developed in the research has two gears:transportation range and technological range. The distinctive feature of the transmission is the use ofthe ZK tank steering systemdeveloped by the researchers of BMSTU (G.I. Zaychik, M.A. Kreynes, M.K. Kristi).The authors have studied the impact ofthe design parameter of the planetary gear sets of the ZK mechanism on the tractor performance. The torques and drive motor rotor speeds providing required performance in a turn as a functions of the planetary gear design parameter have been calculated. Also the time of the tractor full turn around its center of mass and around one braked track when the transmission operates in the transport and technological ranges has been found. An finaly, the impact of the tractor transmission parameters on the maximum tractor speed at manoeuvring has been analysed. The results of the analysis were used for selection of the electric motor output power providing a comfortable work for the tractor operator.

ANN‐based method for parametric modelling and optimising efficiency, output power and material cost of BLDC motor

This study presents a new method for parametric modelling and optimisation of a permanent-magnet brushless DC (BLDC) motor. We proposed an artificial neural network (ANN)-based metric technique to combine and optimise different objective functions of a BLDC motor using ANN-based models and compared with conventional optimisation methods with analytical models. To proceed with this optimisation problem, the function should be minimised. For applying constraints to this problem, a simple method called penalty factor is proposed, in which a penalty term was added to the function when the constraints are violated. We considered three goals in this optimisation: efficiency maximisation, speed maximisation and material cost minimisation. Since the load is constant torque in our case, more speed means more powerful motor, and to achieve the minimum material cost goal the volume of the magnet is set as an objective function. To find the optimum geometric parameters, we used gradient-based method subject to non-linear magnetic constraints. All the obtained results were validated by Ansoft Maxwell. Optimising using the proposed method including ANN-based models does not require knowledge about complicated electric/magnetic equations. Also, ANN-based BLDC motor model is more accurate than analytical models and faster than existing models in simulation tools.

Performance Evaluation of an Electromagnetic Free Piston Compressor Without Permanent Magnets

The performance of a linear free piston gas compressor is investigated in this study. Two compressor pistons are mounted on a robust reciprocating cage mover, which is driven by a double-stator linear induction machine. Since the beginning of the 21st century, many permanent-magnet machines were investigated due to their high power density and efficiency. Less attention has been paid to linear induction machines (LIMs) that stand out through the fact that they do not require expensive rare-earth magnets, and moreover, they are insensitive to strong magnetic fields, high temperatures, and harsh working conditions. This enables them to be used with corrosive media, e.g., for a hydrogen compressor. Therefore, a prototype of a potentially more robust electromagnetic free piston gas compressor was built. It is evaluated on two test benches: First, the LIM is tested with a load motor that enables the measurement of the mechanical output power, and second, the free piston gas compressor is tested with ambient air and the discharge pressure and output flow rate are measured. The electrical power consumption, the mechanical output power of the linear motor, and the pneumatic output power of the free piston compressor are determined for various operating conditions. The measurement results are presented and the average cycle efficiencies are calculated. Moreover, the average cycle power losses of the LIM are analyzed.

Drivetrain modelling and parameter calculation for an electric bus with fixed or 2-speed gearbox

This paper presents drivetrain calculations for an electric bus. Parameters of motor, gears and motor efficiency map are used. The goal is to select the suitable motor and gearbox. Driving cycle SORT2 and real life driving cycles measured on bus lines are used. Based on the bus manufacturer assignment, only permanent magnet synchronous machines are considered. The motor output power is considered in the range of 120-160 kW. The selection of axle gear ratios was limited to 6.19, 6.5 and 7.35, as those are readily available. The gearbox was either a fixed one, with gear ratio of 1.8, or a 2-speed gearbox with a gear ratio of 1 and 1.8. The calculations have shown, that a 2-speed gearbox can decrease the energy consumption. The improvement is in the range of 1-3% dependent on the motor option and driving cycle.

Defect Diagnosis of Disconnector Based on Wireless Communication and Support Vector Machine

Focusing on the shortage of mechanical defect detection and diagnosis technology for disconnectors, a wireless monitoring method for the mechanical state of disconnectors is proposed. The split-core current sensors and improved voltage sensors are used to measure the motor currents and voltages of the disconnector under typical mechanical states at different working voltages. The wireless communication network is used to upload the acquisition data to the cloud server quickly, and the received data are processed by the software system. By comparing and analyzing the curves of current, input power, and output power under different states, it is concluded that the motor output power can adequately reflect the mechanical state of the disconnector. Twenty-three time-domain features of the output power time curve are extracted to form the original feature vector. Kernel principal component analysis (KPCA) method is used to reduce the dimension of the nonlinear features, and the Fisher's criterion function is constructed to determine the width parameter of the kernel function in the feature optimization. Grid search algorithm is used to optimize the kernel parameters of the support vector machine (SVM), and the trained SVM model is used to classify the mechanical state data whose working voltage part is known, and part is unknown, with a classification accuracy of 100%. The results show that the proposed wireless monitoring method can effectively diagnose the mechanical state of the disconnector and has a good generalization ability.

Sucker Rod Pump Working State Diagnosis Using Motor Data and Hidden Conditional Random Fields

In oil exploitation, the short maintenance period and the poor real-time performance of dynamometer card sensors limit the timely working state diagnosis for sucker rod pumps (SRP). The motor is the power source of the SRP that provides all the energy required to lift the oil from underground to surface. The motor power output is highly associated with the working state of the entire equipment. Thus, this article proposes a new strategy to predict the working state of SRP based on motor power. First, seven novel features are extracted from motor power data to support the modeling and diagnosing processes, with the consideration of the significant parameters such as valve's working points and the operating cycle of SRP. Moreover, a custom-designed multiple hidden conditional random fields model with time window is employed as the classifier to identify different working states. At last, the proposed method is validated by a set of motor power data collected from wells by a self-developed device. The experimental result demonstrates the effectiveness of the proposed method for the working state diagnosis of SRPs.

Piezoelectric Motor Utilizing an Alumina/PZT Transducer

To enhance the torque and output power of the rod-shaped piezoelectric rotary motors, in this article, we employ alumina to substitute the metal parts of the transducers considering that the high Young's modulus of alumina may avoid preload-induced vibration reduction and enable the transducers to generate the high driving force. Besides, alumina exhibits a relatively low density compared to most of the materials commonly used as the vibrating bodies (except aluminum alloy); this probably enhances the power densities of the piezoelectric motors. To assess the validity of our proposal, we constructed a Langevin-type alumina/lead–zirconate–titanate (PZT) motor and investigated its load characteristics. The transducer of 35 mm in outer diameter operated in orthogonal bending (B2) modes and drove the rotor with its end surface. The alumina/PZT motor yields the maximal torque and maximal output power of 1.56 N·m and 26.0 W, respectively, both of which exceed those of the metal/PZT motors having identical structure and working in B2 modes. Additionally, its power density reaches 56.3 W/kg, relatively high among the rod-shaped rotary motors although some of which work in more powerful modes. This article validates the effectiveness of our proposal and provides a new approach to improve the performance of the rod-shaped piezoelectric rotary motors.

Design for the Interior Permanent Magnet Synchronous Motor Drive System Based on the Z-Source Inverter

The permanent magnet synchronous motor (PMSM) running above the base speed requires flux-weakening control, which is usually realized by the direct-axis demagnetization current generated by the vector control, thus leading to a decrease in the system efficiency in the flux-weakening region. In addition, the motor power output range is limited by the inverter output voltage and current level. In this paper, a Z-Source drive PMSM control system with adjustable DC-link voltage was proposed to improve the efficiency of the motor system. The proposed system was experimentally verified. The response time of DC-link voltage is 10 ms and the overshoot is 3%, indicating good dynamic characteristics. Compared with the flux-weakening scheme, the Z-Source inverter scheme can achieve higher efficiency (about 3%) when the PMSM speed was set to 650 r/min.

운전 전압 조건에 따른 고하중 대차 견인용 유도전동기의 출력 및 손실 특성 해석

운전 전압 조건에 따른 고하중 대차 견인용 유도전동기의 출력 및 손실 특성 해석

Fluid flow and heat transfer analysis of TEFC machine end regions using more realistic end‐winding geometry

Here, a typical small low-voltage totally enclosed fan-cooled (TEFC) motor (output power ∼10 kW) has been studied using computational fluid dynamics. The complexity of the end-winding geometries, often consisting of several insulated copper strands bound together, provides a challenge to the modelling and analysis of heat transfer and fluid flow phenomena occurring in the end region, which typically is an area of most interest for thermal management. Approximated geometries are usually employed in order to model the end windings to reduce the analysis time and cost. This paper presents a comparison of two cases, a typical simplified geometry and a more realistic geometry of end windings, and uses these cases to highlight the challenges and impact on predicted heat transfer. A comparison of the two models indicate that the different representations of end winding geometries can affect the heat dissipation rate through the outer housing by up to 45%.