The devastating impact of Covid-19 pandemic accelerated the shift to e-learning in the higher education. Particularly in the electrical machines courses, that often include laboratory experiments. ...However, no detailed models of DC motors, developed in MATLAB/Simulink, were reported in literature. Hence, in this paper, a virtual laboratory consist of models of DC motors was built for the first time. The proposed models are easy to use and modify, and allow all machines’ parameters to be altered for students to replicate easily to support and enhance the learning process of electrical machines courses. Consequently, the developed models are effective tools for educational and research purposes. Dynamic models of DC motors were developed using MATLAB/Simulink, namely separately excited, permanent magnet, shunt-connected and series-connected DC motors. Two different approaches for modelling were proposed, the block diagram representation and Simscape based models. The two modelling methods were validated against the built-in DC machine model. The proposed models are easy to use and modify, and allow all machines’ parameters to be altered for monitoring and comparison purposes. Consequently, the developed models are effective tools for research and educational purposes.
In this article, a novel method is proposed to reduce the dc-link capacitance of the brushless dc motor (BLDCM) system. In the proposed strategy, the charging mode of dc-link capacitor is designed to ...improve the energy stored by dc-link capacitor in the charging process instead of reducing the discharge time of dc-link capacitor used in previous article. The new modulation strategy and controller is designed to pump the dc-link capacitor voltage and ensure that it exceeds the ac voltage peak. The proposed modulation strategy has three vectors. The charging vector is used to improve the dc-link capacitor voltage, and the effective vector and zero vector are used to adjust the motor speed. For practical application, we provide an engineering calculation method to get the dc-link capacitance, and prove that the dc-link voltage can exceed the average voltage of the BLDCM. The experimental results verify the correctness of the theoretical analysis and the feasibility of the proposed method.
Recently, wireless power transfer for electric motor technology has been studied, where the primary side can drive the motor without physical contact, so the load motor can be employed in isolated ...environments. This article proposes a wireless permanent-magnet brushless DC (PM-BLDC) motor. Prominently, the secondary side does not involve any motor control chip, as the motor is fully controlled by the WPT controller at the primary side. The key is to employ three widely orthogonal channels with six LC tuning circuits at the secondary side, which can replace the motor controller to regulate the secondary inverter. Thus, the robustness of the motor side is ruggedized and highly improved by eliminating the most fragile component, i.e., the controlling microchip. Circuit simulations and an experimental prototype verify and demonstrate that the proposed three-phase PM-BLDC motor can be driven wirelessly with a single primary controller from 400 to 4000 rpm with 20 mm wireless power transfer distance, and the transmission efficiency can be as high as 80.2%.
Regenerative braking can improve energy usage efficiency and can prolong the driving distance of electric vehicles (EVs). A creative regenerative braking system (RBS) is presented in this paper. The ...RBS is adapted to brushless dc (BLDC) motor, and it emphasizes on the distribution of the braking force, as well as BLDC motor control. In this paper, BLDC motor control utilizes the traditional proportional-integral-derivative (PID) control, and the distribution of braking force adopts fuzzy logic control. Because the fuzzy reasoning is slower than PID control, the braking torque can be real-time controlled by PID control. In comparison to other solutions, the new solution has better performance in regard to realization, robustness, and efficiency. Then, this paper presents the simulation results by analyzing the battery state of charge, braking force, and dc bus current under the environment of MATLAB and Simulink. The simulation results show that the fuzzy logic and PID control can realize the regenerative braking and can prolong the driving distance of EVs under the condition of ensuring braking quality. At last, it is verified that the proposed method is realizable for practical implementation.
Electric vehicles (EVs) usually face many challenges such as long charging time, frequent discharging, and battery life deterioration. These can be addressed by introducing the capability of wireless ...power transfer (WPT) to the unit that can store the regenerative braking energy. A hybrid energy storage system (HESS) model is shown in this research, consisting of a battery and supercapacitor combination, connected through a bi-directional converter. This topology includes three systems connected to the dc-link, namely, BLDC motor drive system, the HESS, and the WPT system where the WPT system supplies power to the system throughout the drive cycle. Battery has limited power density whereas supercapacitors have limited energy density, hence a combination of both the storage units enables us to have an optimized storage system. Apart from that, a supercapacitor also contributes to battery life extension by redirecting the frequent charging and discharging phenomena. The proposed configuration is simulated in MATLAB environment and practically verified by using a BLDC motor. The proposed topology suits low voltage EVs to run in stop-and- go traffic situation or hilly areas. Regenerative braking of BLDC motor allows it to run as a generator for a while allowing the generated power to boost and store back into battery/supercapacitor. This paper proposes a simultaneous wireless charging method to allow the vehicle to charge while in motion. This research is potentially a future prospective of the developing technology in terms of EVs.
Choosing sine-wave instead of square-wave shaped currents to drive a brushless DC (BLDC) motor can increase the energy-efficiency up to 9.5%.But, unfortunately, for sine-wave setpoint current ...generation, the typical electronic or sensing low-resolution commutation feedback techniques become unavailable. For broad industrial employability, other sensing techniques such as computationally complex observers or signal injection methods requiring access to the switching states of the power electronics are not preferred. This raises the need to develop a computationally sufficient simple sensorless controller that optimizes the energy efficiency. Therefore, the authors propose a PID algorithm controlling the estimated load angle technique that enables sinusoidal current supply without the need for position feedback or user input. The aim is to implement a controller for dynamic speed-varying BLDC motor applications, which means that accurate speed trajectory tracking behavior and high robustness against load changes should be guaranteed. The application-dependent PID settings for setpoint and disturbance rejection control are estimated during an initialization speed trajectory based on only one stator winding current and voltage measurement. The proposed control algorithm is validated through experimental measurements on a BLDC motor with a nominal speed and power of 3000 r/min and 225 <inline-formula><tex-math notation="LaTeX">\mathrm{W}</tex-math></inline-formula>, respectively.
Electric vehicles (EVs) are playing a vital role in sustainable transportation. It is estimated that by 2030, Battery EVs will become mainstream for passenger car transportation. Even though EVs are ...gaining interest in sustainable transportation, the future of EV power transmission is facing vital concerns and open research challenges. Considering the case of torque ripple mitigation and improved reliability control techniques in motors, many motor drive control algorithms fail to provide efficient control. To efficiently address this issue, control techniques such as Field Orientation Control (FOC), Direct Torque Control (DTC), Model Predictive Control (MPC), Sliding Mode Control (SMC), and Intelligent Control (IC) techniques are used in the motor drive control algorithms. This literature survey exclusively compares the various advanced control techniques for conventionally used EV motors such as Permanent Magnet Synchronous Motor (PMSM), Brushless Direct Current Motor (BLDC), Switched Reluctance Motor (SRM), and Induction Motors (IM). Furthermore, this paper discusses the EV-motors history, types of EV-motors, EV-motor drives mathematical modelling, and design procedure of EV-motors. The hardware results have also been compared with different control techniques for BLDC hub and SRM. Future direction towards the design of EVs by a critical selection of motors and their control techniques to minimize the torque ripple and other research opportunities to enhance the performance of EVs are also presented.
Motors for Ship Propulsion Kirtley, James L.; Banerjee, Arijit; Englebretson, Steven
Proceedings of the IEEE,
12/2015, Letnik:
103, Številka:
12
Journal Article
Recenzirano
Odprti dostop
Electric propulsion of ships has experienced steady expansion for several decades. Since the early 20th century, icebreakers have employed the flexibility and easy control of direct current (dc) ...motors to provide for ship operations that split ice with back and forth motion of the ship. More recently, cruise ships have employed diesel-electric propulsion systems to take advantage of the flexibility of diesel, as opposed to steam engines, and because the electric plant can also be used for hotel loads. Research vessels, ferries, tankers, and special purpose vessels have also taken advantage of increased flexibility and fuel efficiency with electric propulsion. Today, the U.S. Navy is building an "all electric" destroyer to be named "Zumwalt," which employs two induction motors for propulsion. There are several different classes of motors that might be considered for use in ship propulsion, ranging from dc (commutator) motors through conventional induction and synchronous motors to permanent magnet synchronous machines, doubly fed machines and superconducting alternating current (ac) and acyclic homopolar machines. This review paper describes features of some of the major classes of motor that might be used in ship propulsion.
The Wolverine is a mobile, wearable haptic device designed for simulating the grasping of rigid objects in a virtual reality interface. In contrast to prior work on wearable force feedback gloves, we ...focus on creating a low cost and lightweight device that renders a force directly between the thumb and three fingers to simulate objects held in pad opposition (precision) type grasps. Leveraging low-power brake-based locking sliders, the system can withstand over 100N of force between each finger and the thumb, and only consumes 0.24 mWh (0.87 joules) for each braking interaction. Integrated sensors are used both for feedback control and user input: time-of-flight sensors provide the position of each finger and an IMU provides overall orientation tracking. This paper describes the mechanical design, control strategy, and performance analysis of the Wolverine system and provides a comparison with several existing wearable haptic devices.
This paper presents fault-tolerant control techniques for five-phase permanent-magnet motors with trapezoidal back electromotive forces under various open-circuit conditions. The proposed ...fault-tolerant control methods use only the fundamental and third-harmonic current components for the excitation of the healthy stator phases. The control techniques are developed by applying a concept that correlates the currents in the healthy phases based on their symmetry in space with respect to the fault in a machine. Optimum solutions under the single-phase open-circuit fault condition and double-phase open-circuit fault conditions are presented. The presented solutions are derived to increase the average output torque while reducing the torque pulsations and satisfying the zero-neutral-current constraint. Detailed experimental results are presented for the verification of the proposed solutions.