Bearingless Brushless DC Motor Research Articles

Decoupling control of bearingless brushless DC motor using particle swarm optimized neural network inverse system

Neural network inverse system decoupling control can effectively solve the nonlinear strong coupling problem of bearingless brushless DC motor, but it has the problem of slow convergence and easy to fall into local extreme value. An Improved Particle Swarm Optimization (IPSO) algorithm has been employed to optimize the initial weights of the BP neural network inverse system. Comparisons between traditional inverse system decoupling control and the proposed method through simulations were conducted to confirm the efficacy and superiority of the proposed decoupling strategy. Furthermore, experiment research indicates that effective decoupling control can be achieved for both speed and radial displacement, as well as between the x and y-axis radial displacements, showcasing the good dynamic decoupling performance and stability of the proposed decoupling control strategy.

Particle swarm optimization based interval type 2 fuzzy logic control for motor rotor position control of artificial heart pump

Artificial heart pump (AHP) is employed to replace the native damaged heart and perform its functions. Bearingless brushless DC (BBLDC) motors are used for the implementation of the AHP. BBLDC motor is a highly nonlinear model with uncertainties and its mathematical model is hard to be found accurately. In this paper, BBLDC motor is simulated. Proportional plus integral (PI) controller is proposed to control the rotor suspension current. Furthermore, a type 2 proportional plus integral plus derivative-like fuzzy logic controller (T2 PID-Like FLC) is proposed to control the motor rotor (x, y) positions. Particle swarm optimization (PSO) technique is employed to find the best controller scaling factors and to optimize the controller inputs membership functions distribution within its universe of discourse. Simulation results showed enhancement in levitating the rotor to the required position, when using T2 PID-like FLC as compared with using type 1 PID-like fuzzy logic controller. The enhancement is measured using integral of absolute error (IAE) as a cost function to achieve 64.18% and 81.81% in the x and y axes respectively. The Performance of the motor is enhanced by 20%, which decreases the rotor oscillation and increases the ability to withstand the system disturbances and nonlinearity

Simulation Design of Blood-pump Intelligent Controller Based on PID-like fuzzy logic Technique

This paper presents a blood pump with a bearingless brushless DC motor, supported by speed, torque, and suspension force controllers. Simulation of the pump motor and its controllers tested by MATLAB/Simulink. Two Proportional plus Integral (PI) controllers are employed for controlling the rotational speed and torque of the motor. For controlling the suspension force a comparative study is presented between the Proportional plus Integral plus Derivative (PID) controller and two inputs PID-like Fuzzy Logic Controller (FLC). A particle swarm optimization technique is used to find the best values for the controller’s parameters. The results of the speed and torque controllers exhibit a good time response to reach the desired speed with a short period of time and to decrease the distorting effects of the load torque successfully. Under similar conditions, the PID-like FLC that controls the suspension forces shows a better time response compared to the PID controller. An enhancement in the responses is rated between 18% and 49%, measured using the absolute integral of error criteria on the x and y axes, and in the processing, time rated between 38% and 47%, very high oscillation suppression capability is observed in the PID-like FLC response

Speed and Displacement Control System of Bearingless Brushless DC Motor Based on Improved Bacterial Foraging Algorithm

To solve the deficiencies of long optimization time and poor precision existing in conventional bacterial foraging algorithm (BFA) in the process of parameter optimization, an improved bacterial foraging algorithm (IBFA) is proposed and applied to speed and displacement control system of bearingless brushless DC (Bearingless BLDC) motors. To begin with the fundamental principle of BFA, the proposed method is introduced and the individual intelligence is efficiently used in the process of parameter optimization, and then the working principle of bearingless BLDC motors is expounded. Finally, modeling and simulation of the speed and displacement control system of bearingless BLDC motors based on the IBFA are carried out by taking the software of MATLAB/Simulink as a platform. Simulation results show that, speed overshoot, torque ripple and rotor position oscillation are dramatically reduced, thus the proposed method has good application prospects in the field of bearingless motors.

Suspension Force Control System Design and Simulation for Bearingless Brushless DC Motor

A bearingless brushless DC motor is a new type of high performance motor, which integrates the function of magnetic bearings into a brushless DC motor. In this paper, the suspension force control system is improved and optimization designed according to the radial suspension force mathematical model. The bearingless brushless DC motor control system model is established with the aid of Matlab/Simulink software. From the simulation results, it is confirmed that the rotor shaft is stably suspended without the mechanical contacts. The proposed suspension control system is found suitable to realize the stable suspension of the rotor in the bearingless brushless DC motor.

Research on Drive and Control System of Bearingless Brushless DC Motor for Satellite Flywheel

Compared with the complex structure and unsatisfactory performance of traditional flywheel drive system, the proposed strategy adopts bearingless brushless DC motor as the drive actuator of flywheel. The direct torque control which combines the space voltage vector pulse width modulation is presented to control the system. Moreover, a simulation system is built with Matlab/Simulink toolbox. From the simulation results, the proposed control strategy is verified and the rotor can be stably suspended by suspension force along the central axis.

Combined Discrete Space Voltage Vector with Direct Torque Control for Bearingless Brushless DC Motor and Closed-Loop Suspended Force Control

In order to improve the performance of bearingless brushless DC motor, a closed-loop suspended force controller combining the discrete space voltage vector modulation is applied and the direct torque control is presented in this paper. Firstly, we increase the number of the control vector to reduce the torque ripple. Then, the suspending equation is constructed which is spired by the direct torque control algorithm. As a result, the closed-loop suspended force controller is built. The simulated and experimental results evaluate the performance of the proposed method. The more advantage is that the proposed algorithm can achieve the fast torque response, reduce the torque ripple, and follow ideal stator flux track. Furthermore, the motor which implants the closed-loop suspended force controller cannot only obtain the dynamic response rapidly and displacement control accurately, but also has the characteristics of bearingless brushless DC motor (such as simple structure, high energy efficiency, small volume and low failure rate).

Magnetic Suspension Performance of a Bearingless Brushless DC Motor for Small Liquid Pumps

This paper presents the experiment results from the testing of a magnetic suspension system in a bearingless brushless dc motor. This machine is suitable for use in small liquid pumps. The bearingless motor structure, the principle of the suspension force generation, and the magnetic suspension control strategy are proposed by the author. A prototype bearingless brushless dc motor is designed using computed results from a finite-element method simulation of the system. The simulation is experimentally verified using a prototype machine where the rotor is successfully suspended without mechanical contact when it drives a liquid pump at the maximum rotational speed of 2200 r/min and the maximum fluid flow of 8.2 L/min. This result shows that the proposed bearingless brushless dc motor is suitable as the drive for small liquid pumps.

Nonlinear Feedback Control of a Bearingless Brushless DC Motor

The demands on bearingless drive configurations concerning performance as well as costs are high. The proposed bearingless brushless DC motor consists of five concentrated coils in a symmetrical arrangement, which generate radial forces and motor torque simultaneously in interaction with a permanent-magnet-excited disk-shaped rotor. Additionally, tilting deflection and the axial position of the rotor are stabilized passively by means of magnetic reluctance forces. Thus, system costs can be reduced significantly compared to a conventional bearingless motor setup, which actively stabilizes all 6 DOF. Due to the nonlinearity of the plant, the use of linear control design methods alone is not suitable for achieving a high operation performance. This paper introduces a novel radial position and motor torque control algorithm for a bearingless brushless DC motor based on the theory of feedback linearization. Thereby, the combined model of translatory and rotatory dynamics can be split into independent linear systems by means of a nonlinear change of system coordinates and a static-state feedback. Experimental results demonstrate the effectiveness of the proposed approach.