Simplified fuzzy logic controller to improve disturbance rejection with space vector in induction motor drives

• Main Author: Salleh, Zulhisyam
• Format: Thesis
• Language: English; English
• Published: 2021
• Subjects: T Technology (General); TJ Mechanical engineering and machinery
• Online Access: http://eprints.utem.edu.my/id/eprint/26027/1/Simplified%20fuzzy%20logic%20controller%20to%20improve%20disturbance%20rejection%20with%20space%20vector%20in%20induction%20motor%20drives.pdf; http://eprints.utem.edu.my/id/eprint/26027/2/Simplified%20fuzzy%20logic%20controller%20to%20improve%20disturbance%20rejection%20with%20space%20vector%20in%20induction%20motor%20drives.pdf; http://eprints.utem.edu.my/id/eprint/26027/; https://plh.utem.edu.my/cgi-bin/koha/opac-detail.pl?biblionumber=121257

Induction motor control is a specific and challenging topic in electrical engineering. The development of renewable energy and electric vehicles is growing rapidly, the topic of induction motor control is gaining major attention for industry and academia. The fast capabilities of modern microprocessors offer consideration of more intelligent and powerful control strategies. Conventional control approaches require complex mathematical models for motors to design controllers for quantities such as speed, torque, and position. Modelbased calculations must be performed accurately for each motor, and the resulting modelbased controllers may not perform well. This research addresses these problems by introducing a new Fuzzy Logic (FL) Controller incorporating space vector pulse width modulation (SVPWM) strategy with vector control for controlling inverter-fed induction motor. The most basic technique used to design FL controllers is based on fixed parameters of two inputs and one output through trial-and-error tuning according to the desired response of the system. Membership functions (MFs), rule bases, and control models refer to the engineering skills and behavioural aspects of the controlled system experience. However, the conventional FL controller also has a demerit due to a high computational burden while running large sale fuzzy rules. Computing time directly affects the performance of the motor drive system during the experiments performed. Simplification of fuzzy rules is one of the popular techniques to reduce the FL controller’s computational demand. However, this technique affects the FL control system’s variable coverage and accuracy in performance degradation. The MFs can be optimised by changing the FLC peak value of the MFs in the drive system to increase the system’s robustness. Thus, this research presented the simplified fuzzy rules based on the phase plane trajectory method and optimised MFs to optimise the speed control performance. This research covered the controller design, modelling, and construction of digital signal processing (DSP). It implemented the designed controller to the experimental setup to improve disturbance rejection at various loads and speeds. The simplified 5-rule FL controller was tested and compared with several simplified standard rules; 25-rules, 9-rules, and 7-rules. The experimental validation has been performed on hardware using a three-phase induction motor, controller, inverter, current and voltage sensors and DSP board. The experiment results have confirmed that the recovery time, Tre of load disturbance for optimised MFs 5-rule is 10ms faster than optimised MFs of 7-rule and the almost identical performance as optimised MFs 9-rule. Therefore, the proposed controller has a significant ability to rapidly overcome load disturbances that can be applied in high-speed motor applications such as electric vehicles and traction systems.