High-performance Brushless DC Motor Research Articles

Optimal Coronavirus Optimization Algorithm Based PID Controller for High Performance Brushless DC Motor

This paper presents an efficient coronavirus optimization algorithm (CVOA) to find the optimal values of the PID controller to track a preselected reference speed of a brushless DC (BLDC) motor under several types of disturbances. This work simulates how the coronavirus (COVID-19) spreads and infects healthy people. The initial values of PID controller parameters consider the zero patient, who infects new patients (other values of PID controller parameters). The model aims to simulate as accurately as possible the coronavirus activity. The CVOA has two major advantages compared to other similar strategies. First, the CVOA parameters are already adjusted according to disease statistics to prevent designers from initializing them with arbitrary values. Second, the approach has the ability to finish after several iterations where the infected population initially grows at an exponential rate. The proposed CVOA was investigated with well-known optimization techniques such as the genetic algorithm (GA) and Harmony Search (HS) optimization. A multi-objective function was used to allow the designer to select the desired rise time, the desired settling time, the desired overshoot, and the desired steady-state error. Several tests were performed to investigate the obtained proper values of PID controller parameters. In the first test, the BLDC motor was exposed to sudden load at a steady speed. In the second test, the continuous sinusoidal load was applied to the rotor of the BLDC motor. In the third test, different operating points of reference speed were selected to the rotor of the BLDC motor. The results proved that the CVOA-based PID controller has the best performance among the techniques. In the first test, the CVOA-based PID controller has a minimum rise time (0.0042 s), minimum settling time (0.0079 s), and acceptable overshoot (0.0511%). In the second test, the CVOA-based PID controller has the minimum deviation about the reference speed (±4 RPM). In the third test, the CVOA-based PID controller can accurately track the reference speed among other techniques.

Minimization of Harmonics in BLDC Motor Drive Using Fuzzy Logic Based Variable Inductor Filter Drive

ABSTRACT Harmonic analysis and its mitigation are very important for high-performance brushless DC motor drives. Conventional fixed LC filter work around its tuned frequency, resulting narrow band for operation. High-frequency current ripples can result in significant damage to the motor bearings. In this paper, afuzzy-based servo controlled variable inductor is proposed as apart of LC filter. Arotary variable inductor is controlled by using DC servo motor connected to it. Rotary variable inductor shaft is to be turned around to adistinct angle to attain imposed inductor value by using DC servomotor position control. This expands its operating frequency range more effectively. The current harmonics are compared for operation with and without the proposed filter. Proposed system was simulated using MATLAB/Simulink and implemented on 2 kW, 48 V, 8 pole pair BLDC motor drive for demonstration. Athree-phase IGBT-based voltage source inverter is used to drive the motor. Experimental results presented validate the effectiveness with improvement in current harmonics elimination by 22%. More importantly, improvement in THD is observed at lower operating frequencies too. This makes the scheme more useful for varying speed/load applications. Reduction in harmonics enhances other performance parameters of the BLDC motor drive.

A Novel Fuzzy Self Tuning Technique of Single Neuron PID Controller for Brushless DC Motor

In this paper, a combination ANN/Fuzzy technique is used to design a Novel Fuzzy Single Neuron PID (NFSNPID) controller to achieve high performance brushless DC motor. The design steps include two parts. The first part uses the genetic algorithm (GA) to find the optimum parameters of Single Neuron PID (SNPID) controller, while the former deals with the design of fuzzy logic control to update the weights of SNPID control online. To demonstrate the designed controller effectiveness, a comparative study is made with between the NFSNPID, Conventional Fuzzy Single Neuron PID CFSNPID and SNPID. All controllers were used to drive, separately, the brushless DC motor against the sudden change of load and operating speed. The performed simulations show better results that motivate for further investigations.

Brushless DC motor tracking control using self-tuning fuzzy PID control and model reference adaptive control

Abstract This paper compares the performance of two different control techniques applied to high performance brushless DC motor. The first scheme is self-tuning fuzzy PID controller and the second scheme is model reference adaptive control (MRAC) with PID compensator. The purpose of the control algorithm was to force the rotor speed to follow the desired reference speed with good accuracy all time. This objective should be achieved for different speed/time tracks regardless of load disturbance and parameter variations. The simulation results presented show that the second control scheme has better performance.

A new robust speed-sensorless control strategy for high-performance brushless DC motor drives with reduced torque ripple

This paper presents an analysis, design, and strategy of a high-performance speed-sensorless control scheme for estimating the phase-to-phase trapezoidal back-EMF of BLDC motor drive by means of a novel stochastic deconvolution technique in the H∞ setting, named robust stochastic H∞ deconvolution filter. In the proposed method, unlike the conventional observer-based approaches, the back-EMF is considered as an unknown input, and no need is felt for the constancy assumption of the rotor position and speed of machine within a short period of the time in the modeling of the BLDC motor which leads to ignoring the back-EMF dynamic at high and variable speed. In addition, since high-speed operation is vital for the motor, an improved approach has also been proposed to reduce the commutation-torque-ripple at high-speed for direct torque control (DTC) strategy of three-phase BLDC motor with 120° conduction mode in parallel with the proposed method due to the fact that drive performance intensely downgrades in this mode.

Design and analysis of speed-sensorless robust stochastic L∞-induced observer for high-performance brushless DC motor drives with diminished torque ripple

This paper aims to present an analysis and design of a high-performance speed-sensorless control scheme for a three-phase brushless DC (BLDC) motor drive by means of a novel observer technique in the induced L∞ norm setting, named robust stochastic L∞-induced observer, with the purpose of reducing torque ripple and increasing system robustness. The proposed observer is used for estimating the phase-to-phase trapezoidal back-electromotive-force (back-EMF) for the BLDC motor merely via utilizing measured line stator currents and voltages in such a way that by estimating the back-EMF, position and speed of the rotor is readily obtained. In contrast to the conventional back-EMF sensing methods, this strategy of utilized drive requires no filtering of current and voltage; furthermore, it does not suffer from any sensitivity to switching noises. Owing to that high-speed operation is vital for a motor, the varying input voltage method is used for realizing the minimization of commutation-torque-ripple in a parallel way to the proposed method since drive performance intensely degrades in this mode. Apart from analytic investigation of the proposed method, two other types of observers, namely, the sliding-mode observer and Kalman filter are compared with the proposed method for the aim of determining steady-state accuracy, dynamic performance, parameter and noise sensitivity, low-speed-operation performance, and computational complexity. Finally, the proposed system has been simulated in different operating conditions of the BLDC motor by computer simulation, and the effects of the proposed speed-sensorless control scheme has been assessed by comparative studies and simulation results. Simulation results authenticate that the proposed method is of excellent robustness and high precision estimation in comparison with sliding-mode and Kalman filter methods under different operating conditions in spite of the existence of measurement noise and electric parameter uncertainty. Therefore, the proposed method with its strong robustness makes it possible for the drive to enable the motor to undergo a stable tensionless operation without facing any problem at high-and low-speeds.

Design of a miniature implantable left ventricular assist device using CAD/CAM technology.

In this study, we developed a new miniature motor-driven pulsatile left ventricular assist device (LVAD) for implantation into a Japanese patient of average build by means of computer-aided design and manufacturing (CAD/CAM) technology. A specially designed miniature ball-screw and a high-performance brushless DC motor were used in an artificial heart actuator to allow miniaturization. A blood pump chamber (stroke volume 55 ml) and an inflow and outflow port were designed by computational fluid dynamics (CFD) analysis. The geometry of the blood pump was evaluated using the value of index of pump geometry (IPG) = (Reynolds shear stress) x (occupied volume) as a quantitative index for optimization. The calculated value of IPG varied from 20.6 Nm to 49.1 Nm, depending on small variations in pump geometry. We determined the optimum pump geometry based on the results of quantitative evaluation using IPG and qualitative evaluation using the flow velocity distribution with blood flow tracking. The geometry of the blood pump that gave lower shear stress had more optimum spiral flow around the diaphragm-housing (D-H) junction. The volume and weight of the new LVAD, made of epoxy resin, is 309 ml and 378 g, but further miniaturization will be possible by improving the geometry of both the blood pump and the back casing. Our results show that our new design method for an implantable LVAD using CAD/CAM promises to improve blood compatibility with greater miniaturization.

Experimental verification of a hybrid fuzzy control strategy for a high-performance brushless DC drive system

This paper describes the design and experimental verification of a hybrid fuzzy control system for a high-performance brushless DC motor drive. Both the design of the fuzzy controller and its integration with the proportional-integral (PI) in a global control system are discussed. The principle, of the proposed control system is to use a PI controller, which performs satisfactorily in most cases, while keeping in the background, a fuzzy controller, which is ready to take over the PI controller when severe perturbations occur. Strategies of the switching control for the hybrid controller is such that the fuzzy controller is activated whenever the resident system exhibits an oscillatory and/or overshoot behavior. Thus, the PI and fuzzy controllers can be managed to take advantage of their positive attributes. Performance of the hybrid fuzzy-PI controller is evaluated through a laboratory implementation. The laboratory implementation is based on a linguistic fuzzy controller whose design is derived from the expert knowledge gained during disturbances. Experimental results have shown excellent tracking performance of the proposed control system, and have convincingly demonstrated the usefulness of the hybrid fuzzy controller in high-performance drives with uncertainties.

A hybrid observer for high performance brushless DC motor drives

Brushless DC motor drive systems are used in a wide variety of applications. These drives may be classified as being one of two types: sinusoidal drives in which there are no low-frequency harmonics in the current waveforms and no low-frequency torque ripple; and nonsinusoidal drives in which there is considerable low-frequency harmonic content, both in the current and torque waveforms. Although sinusoidal drives feature superior performance, they are generally more expensive since rotor position must be sensed on a continuous basis, thus requiring an optical encoder or a resolver, whereas relatively inexpensive Hall-effect sensors may be used for nonsinusoidal drives. In this paper, a straightforward hybrid observer is set forth which enables rotor position to be estimated on a continuous basis using information available from the Hall-effect sensors. The proposed observer is experimentally shown to perform just as well as an optical encoder for steady-state conditions and nearly as well as the optical encoder during transient conditions. The proposed scheme provides designers with a new option for rotor position sensing, one which offers an excellent compromise between accuracy and expense.