Search Results for « BLDC motor drives »

This paper presents the design of a robust speed controller for brushless DC motors (BLDCM) under field-oriented control (FOC). The proposed robust controller integrates extension theory (ET) and sliding mode theory (SMT) to achieve robustness. First, the speed difference between the speed command and the actual speed of the BLDCM, along with the rate of change of the speed difference, are divided into 20 interval categories. Then, the feedback speed difference and the rate of change of the speed difference are calculated for their extension correlation with each of the 20 interval categories. The interval category with the highest correlation is used to determine the appropriate control gain for the sliding mode speed controller. This gain adjustment tunes the parameters of the sliding surface in the SMT, thereby suppressing the overshoot of the motor speed. Because the sliding surface reaching law of the sliding mode controller (SMC) adopts the exponential approach law, the system's speed response can quickly follow the speed command in any state and exhibit excellent load regulation response. The simplicity of this robust control method, which requires minimal training data, facilitates easy implementation. Finally, the speed control of the BLDCM is simulated using Matlab/Simulink software, and the results are compared with those of the SMC using the constant speed approach law. The simulation results demonstrate that the proposed robust controller exhibits superior speed command tracking and load regulation response compared to the traditional SMC.

Abstract These Days Electric tractors are becoming more popular among farmers due to their environmental friendliness. The efficiency, torque responsiveness, and control stability of these systems could be compromised due to the dynamic performance of the Brushless DC (BLDC) motors used. This could happen under different loads and field situations.In order to improve the dynamic performance of electric tractors driven by BLDC motors, this paper presents a FO-FLC, which stands for Fractional Order Fuzzy Logic Controller. Combining the robustness of fractional calculus with the flexibility of fuzzy logic, the proposed controller outperforms PI and integer-order fuzzy controllers in terms of control accuracy and system stability.The FOFLC optimizes its steady-state and transient behavior with operators for fractional-order differentiation and integration, and it can make real-time adjustments to its control settings with fuzzy inference rules. We used MATLAB/Simulink simulations to assess its speed regulation, torque ripple mitigation, and transient response to load disturbance capabilities.When compared to conventional control systems, the FOFLC achieves far better results in terms of torque smoothness, overshoot reduction, and settling time. These findings show that electric tractors powered by FOFLC-based BLDC motor control can improve energy efficiency, drivability, and operational reliability in the future.