Driving parameter survey and experiment on railway drive system by using two or more permanent magnet synchronous motors controlled using one inverter

A new instantaneous torque-control strategy is presented for high-performance control of a permanent magnet (PM) synchronous motor. In order to deal with the torque pulsating problem of a PM synchronous motor in a low-speed region, new torque estimation and control techniques are proposed. The linkage flux of a PM synchronous motor is estimated using a model reference adaptive system technique, and the developed torque is instantaneously controlled by the proposed torque controller combining a variable structure control (VSC) with a space-vector pulse-width modulation (PWM). The proposed control provides the advantage of reducing the torque pulsation caused by the nonsinusoidal flux distribution. This control strategy is applied to the high-torque PM synchronous motor drive system for direct-drive applications and implemented by using a software of the digital signal processor (DSP) TMS320C30. The simulations and experiments are carried out for this system, and the results demonstrate the effectiveness of the proposed control.

This report provides background information on various fractional-horsepower electric motor technologies used for evaporator fan applications in commercial refrigeration and summarizes data from a DOE-sponsored evaporator fan motor laboratory and field demonstration project. This report also extrapolates that data to project the potential economic and environmental benefits resulting from upgrading the current installed base of commercial refrigeration evaporator fan motors to permanent magnet synchronous (PMS) motors.Evaporator fan motors used in commercial refrigeration applications are fractional horsepower in size, responsible for moving air across the evaporator coil, and typically run at one speed. Historically, shaded-pole induction motors have been the most commonly used evaporator fan motors in commercial refrigeration equipment and beverage vending machines. These are the simplest and least expensive type of fractional-horsepower motor, with an efficiency of approximately 20%. Electronically commutated (EC) permanent magnet motors, also known as brushless DC motors, were initially commercialized in the late 1980s, and their use in commercial refrigeration applications has increased within the last 10 to 15 years because of economic incentives and regulatory requirements. State-of-the-art EC motors are approximately 66% efficient. Another induction motor type, the permanent split capacitor (PSC) motor, offers a mid-point between shaded-pole and EC motor price and efficiency levels. PSC motors are typically about 29% efficient.A permanent magnet synchronous (PMS) AC motor that can directly use grid-supplied AC current without the need to rectify to DC has recently been commercialized. This new motor exhibits a peak efficiency of 75% and has the potential to significantly reduce the energy consumption of evaporator fan motors in commercial refrigeration equipment. Laboratory evaluation of evaporator fan motor technologies was performed to quantify and compare the performance of shaded-pole, PSC, EC, and PMS evaporator fan motors in a controlled environment, so as to minimize the influence of external factors and anomalies. The laboratory evaluation included dynamometer testing of the fan motors and airflow testing of the motor/fan assemblies. It was found that the 6–12 W PMS motor exhibited a peak efficiency of 75% with a power factor of approximately 0.9 at a power output of 11 W. It was also found that a 38–50 W PMS motor exhibited a peak efficiency of 82% with a power factor of approximately 0.9 at a power output of 35 W.Airflow testing of shaded-pole, PSC, EC, and PMS motor/fan assemblies was performed using an airflow test chamber, which was designed in accordance with ANSI/AMCA Standard 210-16/ASHRAE Standard 51-16, to measure the performance of the subject motor/fan assembly and to determine the incumbent display case system impedance (AMCA 2016). A family of fan curves (static pressure vs airflow rate and electrical power input vs airflow rate) was generated for the 6–12 W PMS motor/fan assemblies with 8-inch fan blades pitched from 17 to 32 degrees. A similar set of curves was generated for the 38–50 W motors paired with 10 and 12-inch blades. Various incumbent motor/fan assemblies were also tested in the laboratory airflow test chamber and their fan curves were generated.Field evaluation of refrigerated display case evaporator fan motors was accomplished by performing side-by-side comparisons of 6–12 W PMS motors to 6–12 W shaded-pole and EC evaporator fan motors. It was found that, on average, a PMS motor consumes 79% less power and draws 82% less current than a shaded pole motor, and on average, 34% less power and 49% less current than an EC motor. In addition, the PMS motor exhibits an average power factor of approximately 0.82, which is on average 40% greater than that of existing evaporator fan motors.Two field test sites were selected to evaluate the performance of the larger 38 to 50 W PMS evaporator fan motors in walk-in cooler/freezer applications. At each supermarket, two walk-in units were selected for investigation: one walk-in dairy cooler and one walk-in freezer. A 61% decrease in fan motor power was measured when retrofitting existing evaporator fan motors with PMS motors in the walk-in cooler. In addition, a 48% decrease in fan motor power was measured when retrofitting existing evaporator fan motors with PMS motors in the walk-in freezer.The culmination of the field evaluation of fan motor technologies was a whole-store retrofit conducted at a supermarket. Pre- and post-retrofit measurement of evaporator fan motor power in medium- and low-temperature refrigerated display cases and walk-in coolers/freezers was performed. Overall for the whole-store retrofit, the current supplied to all monitored evaporator fan motors was reduced by 52%, the real power was reduced by 46% and the apparent power was reduced by 51% following the retrofit of the 262 evaporator fan motors that w

This paper deals with theoretical analysis and design of permanent magnet (PM) synchronous motors (PMSMs) with minimized cogging force. Recently, many optimal designs for the PMSMs have been done by finite element (FE) analysis, but such analysis generally is time consuming. In this study, the equation of magnetic flux lines existing between PMs and iron cores is expressed geometrically and the cogging force is calculated theoretically without FE analysis. The form of equation is assumed to be the second-order polynomial and the virtual core is used to express the cogging force in analytical model. The cogging force can be calculated by applying the solved flux line equation and the flux density equation to the Lorentz force equation by using the Maxwell stress tensor. The theoretical analysis of minimized cogging force is applied to several prototypes such as synchronous PM planar motor (SPMPM), 2-DOF PMSM with screw motion, and axial flux PM (AFPM) brushless dc motor in this paper, and the analytical results are validated by FE analyses and experiments.

Recurrent modified Elman neural network control of PM synchronous generator system using wind turbine emulator of PM synchronous servo motor drive

In order to estimate the vibration and acoustic noise in a permanent magnet (PM) synchronous motor, the natural frequencies of the stator structure should be determined during the design stage. In this paper, analytical formulas to predict the natural frequencies of the stator are derived. The analytical model of the stator includes stator teeth, winding, stator core, and stator case. It is observed that the natural frequencies calculated with the integrated components exceed those based on the stator core alone only. In order to verify this analytical model, numerical simulation and experimental measurement are carried out using a PM synchronous motor which has 5 pole-pairs and 12 slots structure configuration. Good agreements are observed among the results obtained by analytical formula, simulation and experiment.

Permanent magnet (PM) synchronous motors (PMSMs) have been used to drive a number of vehicles. They have high torque density, high efficiency, and a wide speed range. However, the high cost of PMs is disadvantageous. This paper presents a technique for increasing the torque density by modifying the shape of the PMs and minimizing the magnet volume. The PM characteristics such as flux density, demagnetizing force, PM energy product, and the air-gap flux density are represented by a lumped magnetic equivalent circuit when the thickness and width of the PM are increased for the same volume but with different shapes. The torque, torque ripple, core loss, magnet loss, and efficiency of three interior (IPMSM) models designed by the proposed method are compared by finite element analysis. In addition, the demagnetization of the PM due to high temperature, maximum torque load angle, and an adverse field is analyzed. Finally, the analysis result is compared with that of the experiment to verify the proposed model.

The electric vehicle (EV) industry is developing around the world because of increased air pollution and the rising cost of fuel in traditional vehicles. E-rickshaws are in great demand in nations like India, since three-wheelers are the regular method of transport utilized by citizens. Compared with the induction motor (IM) and switch reluctance motor (SRM), the permanent magnet synchronous motor (PMSM) has the advantages of high power density, high efficiency, and fewer losses. Hence, PMSM is the better choice for E-rickshaw. The efficiency of PMSM is reliant upon the rotor arrangement and materials utilized in the motor. Due to the low cost and simplicity of assembling, silicon steel (SS) is typically utilized in PMSM cores. The intrinsic attributes of SS limit iron loss reduction. The iron loss of amorphous iron (AI) PMSM is less in contrast with SS due to high resistivity, low coercive power, etc. In this paper, efficiency optimization of surface and de-centered PMSM with SS and AI is discussed. The selection of the power rating of PMSM is done based on the E-rickshaw dynamics. The detailed design of PMSM is included. Based on design values, PMSM has virtually evolved from the ANSYS Maxwell stage. The motor parameters are obtained from ANSYS Maxwell, and PMSM is modeled in MATLAB/Simulink.KeywordsE-rickshawEfficiencyPMSMANSYS MaxwellMATLAB/Simulink

For electric vehicles (EVs), permanent magnet synchronous motors (PMSMs) are competitive owing to their high power factor, high efficiency and high power density. In this paper, four types of PMSMs with different rotor topologies are designed with the same motor main dimensions and the same amount of permanent magnet usage. First, the different PMSMs are compared in terms of their torque characteristics. The torque characteristic curves of the four motors are displayed with the control method i <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</sub> =0 for surface-mounted PMSM (SPMSM) and Maximum Torque per Ampere (MTPA) for interior PMSM (IPMSM). It turns out that IPMSM has higher starting torque than SPMSM due to the reluctance torque. Among the three IPMSMs with different rotor structures, V-shape IPMSM and delta-shape IPMSM can provide higher output torque under the same current supply with the higher salient rate. More information on the no-load magnetic density, torque ripple, efficiency and demagnetization problem operated at the peak current is also provided and compared. Then the four PMSMs with the same peak current are further analyzed and compared on the flux-weakening speed-enlarge (FWSE) capability. The results show good FWSE capability for all of the four PMSMs owing to the large peak current. However, the torque of SPMSM in flux-weakening control region is slightly higher than the IPMSMs.

The development of electric and hybrid vehicles has gained increasing attention in recent years. This paper proposes an Electric drive for Hybrid vehicles application and its control strategy to achieve a wide speed range. In these vehicles, important requirements for the electric drive are low weight, small volume, high efficiency and low cost. When choosing the motor for the vehicle drive, the induction motor is an obvious alternative but a permanent magnet synchronous motor (PMSM) can offer advantages in terms of higher efficiency and specific power. In this paper a permanent magnet synchronous machine (PMSM) is used as an electric drive machine. The operation of a PMSM above the base speed is possible by weakening the permanent-magnet excitation by a demagnetizing field component supplied by the stator winding. This can be done by closed loop operation of PMSM. The speed and torque control of the PMSM drive used as hybrid vehicle is controlled by proper tuning the PI controllers. A three level diode clamped inverter using IGBT's has simulated, whose switching sequences are controlled by Space Vector Pulse Width Modulation (SVPWM). A mathematical model of PMSM drive suitable for hybrid vehicle has simulated and proper closed loop control is established by field oriented control method. The entire work is done in MATLAB/SIMULINK.

Permanent Magnet Synchronous Motors (PMSMs) are becoming increasingly popular in traction applications. PMSMs have gained popularity due to their efficiency, compactness and excellent features related to control. This is mainly because of the permanent magnet placement in the rotor, which negates any additional rotor excitation, hence reducing energy losses considerably. This makes them more efficient compared to induction motors. PMSMs also have a high-power density, enabling them to provide more power relative to their size. These features make them highly feasible in electric vehicles and aerospace applications where size and weight are one of the critical aspects. With the possibility of precise and smooth torque control, they are well adapted to applications that have strict requirements for precise speed and position control. Also, PMSMs provide superior dynamic performance with low maintenance since they do not contain brushes and commutators; hence, they are supposed to have a longer life. But PMSMs have also some challenges, the most critical problem that usually faces PMSMs is fault detection, mainly bearing faults. The bearings in PMSMs are critical components, and any defect in those components creates serious mechanical and electrical problems for the motor. Due to its defective state, the bearing may impose the emergence of vibration, raised friction, and wear, leading to inefficiencies, increased heat generation, and, finally, motor failure. Thus, early detection of bearing faults is indispensable; prolonged operation with faulty bearings results in catastrophic damage to the motor, longer downtime, and more expensive repairs. Thus, the fault diagnosis at the inception stage has become very critical now. In this paper, a technique based on cyclization dominant frequency analysis for bearing fault detection using the phase current of a motor has been proposed. The results have shown that this method can be used for monitoring and detecting bearing faults without the use of any additional sensor.

An adaptive model-output-following controller using a variable structure system (VSS) approach is proposed in this paper. Only output from the plant is needed in the VSS control law to enhance the robustness of the control system. The position control of a permanent magnet (PM) synchronous motor servo drive using the proposed control strategy is illustrated. First, an integral-proportional (IP) position controller is systematically designed according to the prescribed drive specifications of the command tracking. Next, in order to allow the given specifications to be maintained under wide operating conditions, the state-space model of the systematically designed inner IP speed loop in the nominal case is chosen as the reference model. Then, the proposed adaptive controller based on VSS theory is designed and augmented to the inner speed loop to preserve the control performance. Simulation results show that the proposed control approach results accurately model the following characteristic and is robust with regard to plant parameter variations and external load disturbance.

The permanent magnet synchronous motor (PMSM) and the brushless DC motor (BDCM) have many similarities; they both have permanent magnets on the rotor and require alternating stator currents to produce constant torque. For application considerations, these two motor drives have to be differentiated on the basis of known engineering criteria. Some of the criteria used to assess these two machines include power density, torque per unit current, speed range, feedback devices, inverter rating, cogging torque, ripple torque, and parameter sensitivity. Guidelines for the appropriate machine to be used for a given application are given based on the results of the criteria. >

The Permanent Magnet Synchronous Motor (PMSM) is widely used in many fields. Aiming at nonlinearity, strong coupling and uncertainty of the PMSM, this paper proposes a nonlinear multi-input multi-output (MIMO) decoupling PMSM algorithm based on Active Disturbance Rejection Control (ADRC). A Lower-Upper matrix factorization approach is introduced to solve a general inverse of the measured time-varying matrix in real-time decoupling ADRC. This PMSM is based on the vector control. First, the PMSM model and vector control are simulated. Then, a first-order ADRC is introduced and used to replace the PID controller in the d and q axis of PMSM respectively. The simulation shows that the replaced system has a smaller fluctuation, faster response and better stability. Finally, the nonlinear MIMO decoupling ADRC and its inverse matrix method are deduced. Then, the decoupling PMSM control based on ADRC is verified. The simulation shows that this system has a better static and dynamic performance, and it conforms to the PMSM characteristics better. All this shows that the nonlinear MIMO decoupling ADRC is a better strategy for the PMSM. The presented algorithm also has advantage in method compared with some recent results of decoupling PMSM control.

The aim of this paper is to address the problem of the electronic implementation of chaos control using a single controller and synchronization of chaotic permanent magnet synchronous motor (PMSM). Firstly, different dynamical behaviors of the PMSM including steady state, periodic and chaotic behaviors are found using numerical methods such as two-dimensional largest Lyapunov exponents graph associated with two parameters of PMSM. Secondly, two simple and single controllers are designed and added to the chaotic PMSM in order to suppress chaotic behavior. The performance of the two proposed simple and single controllers is illustrated by numerical simulations. Thirdly, controllers are designed to achieve synchronization of unidirectional coupled identical chaotic PMSMs. Numerical simulations are also used to verify the effectiveness of the synchronization. Finally, the existence of chaos in PMSM and the physical feasibility of the proposed two simple and single controllers as well as the chaos synchronization are validated through the circuit implementation on OrCAD-PSpice software. The circuit implementation results comply fairly with those of the numerical simulation results and establish that the existence of chaotic behavior in the PMSM and the achievement of chaos synchronization in unidirectional coupled identical PMSMs designed and the two single controllers designed are effective and successful in suppressing chaotic behavior in PMSM.

In our high-power flywheel energy storage system, the heavy and large flywheel is rotated by the electromagnetic torque of a permanent-magnet (PM) synchronous motor (PMSM) and, in case of a breakdown of electric current, this motor used as a generator supplies electric energy to the various electric utilities using mechanical rotation energy of the flywheel. Thus, the dynamic performance of the flywheel is related to the electromagnetic torque for the motoring and generating power of the PMSM/G. Moreover, in the idling mode without generating loads, speed reduction of the flywheel is mainly caused by drag torque generated in the slotless iron-cored stator of this PM machine. In this paper, the operating torque, defined as the electromagnetic torque and drag toque, is estimated from the magnetic-field analysis by the PM rotor with diametrical magnetization. Also, the dynamic performance of the flywheel, according to the driving mode, is simulated from dynamic modeling of the PMSM/G with the operating torque and verified by the experiment.