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Summary: In this study, couple inductor‐based buck power factor correction (PFC) converter is designed to mitigate dead zones of the converter. To minimize switching losses, all switches are controlled using a soft switching method, eliminating the need for snubber circuits. The circuit is controlled by an analog UC3843 pulse width modulation (PWM) integrated circuit (IC), providing natural PFC capability, which simplifies control and offers advantages in terms of size and cost compared to conventional ones. Simulation studies and prototype implementation are carried out to evaluate performance of the topology. The converter operates within a voltage range of 90–280 Vrms and has a power rating of 150 W. The results from both simulation and experimental analyses indicate that power factor (PF) of the circuit exceeds 98% and total harmonic distortion (THD) of the input current is found to be below 5% under various input voltage and load conditions. Furthermore, proposed topology demonstrated high efficiency, with measurements of 93% at full load and 95.6% at half load under 220 Vrms input voltage and 80 Vdc output voltage conditions. Outcomes highlight that the proposed topology achieves pure sinusoidal input current and exhibits competitive performance compared to other topologies used in the industry. [ABSTRACT FROM AUTHOR]

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, implementation of incremental fuzzy control (IFC) method on field programmable gate array (FPGA) is investigated for gimbals and fins of missiles that include brushless direct current (BLDC) motors and its comparison with conventional proportional-integral (PI) control method are analyzed. BLDC motors are widely used in two important parts of guided missiles due to their high performance. Firstly, gimbals usually consist of seeker cameras, whose axis controls are provided by BLDC motors. These motors provide two axis seeker camera motions, so that the missiles can trace the target. Secondly, missiles can be guided to intended direction by BLDC motors that are used in the control system of fins. According to these important roles, controlling of BLDC motors is very important for defense industry. Therefore, performance of FPGA-based conventional PI and proposed IFC methods on BLDC motors are analyzed in detailed in terms of both simulation and experimental study. Simulation results are obtained by using MATLAB/Simulink program. Also, an FPGA-based test bench is used for experimental studies. Results obtained from simulation and experimental set up are compared and it is proved that the implementation of proposed IFC method improves the BLDC motor performance used in missiles compared to the conventional PI control method. [ABSTRACT FROM AUTHOR]

Summary: Matrix converter has many advantages such as no need for high value filters, capability of bidirectional energy conversion and no need for DC bus. Nevertheless, modulation methods are very difficult and require high computational effort. Therefore, model predictive control method has been implemented to simplify the complexity of this topology. However, the weakness of this control method is using mathematical model and affected by parameter changes due to the external disturbances, frequency and temperature variations. To eliminate the variations of rotor resistance and stator resistance, a reduced‐order extended Kalman filter has been implemented as an observer to estimate them resulting from frequency and temperature variations, sensor noise or uncertainties. The algorithm is performed using TMS320F28335 digital signal processor that is a 32‐bit floating‐point processor operating at 150 MHz. Results obtained from experimental setup are compared with the previous studies and the performance of the proposed method is confirmed. [ABSTRACT FROM AUTHOR]

Background: MC has many advantages such as no need for high‐value filters, capability of bi‐directional energy conversion and no need for DC bus. However, distortion in the source voltage, such as noise or harmonics may be reflected directly on the load side due to the lack of any storage elements. Purpose This paper proposes an effective method for finite control set model predictive control (FCS‐MPC) implemented in matrix converter (MC) to overcome these possible drawbacks and to improve source current quality under distorted source voltage conditions. Method: Proposed approach based on instantaneous unity power factor (IUPF) strategy is applied to compensate for disturbance in the source voltage. In order to achieve this, phase‐locked loop (PLL)‐based virtual source voltage is generated at the same frequency as the source voltage to obtain sinusoidal reference current to be used in FCS‐MPC. Design Proposed method is performed using TMS320F28335 Digital Signal Processor (DSP) that is a 32‐bit floating‐point processor operating at 150MHz. Results: Experimental results show that it is possible to obtain sinusoidal current waveforms on both sides despite the distortions in source voltage or harmonics due to the proposed virtual source voltage strategy. Conclusion: The results obtained from the experimental set‐up confirm the performance of the proposed method. [ABSTRACT FROM AUTHOR]

A comparison of fuzzy self-tuning (FST), sliding mode control (SMC) and conventional proportional--integral (PI) control methods is performed under unbalanced grid conditions using a bridgeless power factor correction (PFC) converter. The bridgeless PFC converter operates the correction of AC line current to obtain a DC output voltage without full bridge rectifier based on these control methods. These control methods generate the duty cycles to provide higher unity power factor and lower total harmonic distortion of input current, even if AC line voltage is distorted. This study focuses on the performance analysis of FST and SMC methods adaptation to the input current for the bridgeless PFC converter and comparing with the conventional PI controller. Although the SMC method is only used in the current control loop, the FST method is used in both current and voltage control loops for eliminating harmonics of input current and regulating of output voltage. The performance of control methods is evaluated with a TMS320F2812 digital signal processor. The simulation and experimental results are compatible with the limits for harmonic current emissions, IEC 61000-3-2 and show that the FST and SMC are better than the conventional PI control method and FST is superior to the SMC. [ABSTRACT FROM AUTHOR]

In this study, the performance analysis of Fuzzy Self Tuning (FST) control method for Bridgeless Power Factor Correction (PFC) converter is proposed. The Bridgeless PFC converter based on FST method operates AC line rectification to result in DC output voltage without full-bridge rectifier. The proposed method generates the duty cycles to provide higher Unity Power Factor (UPF) and lower Total Harmonic Distortion (THD) of input current, even if AC line voltage consists of harmonics. Although Ziegler-Nichols method is very important to tune the coefficients of PI control method, it cannot guarantee to be always effective. For this reason, this study investigates the design of FST control method that tunes the coefficients of Kp, and Ki gains that are used into inner and outer control loops. These parameters are self-tuned to make them more general, to achieve minimum steady-state error, and to improve the dynamic behavior such as overshoot. Performance of proposed system was implemented for 1 kW Bridgeless PFC converter board with a TMS320F2812 DSP. The simulation and experimental results are compatible with the limits for harmonic current emissions, IEC 61000-3-2 and show that the proposed method is better than traditional ones. [ABSTRACT FROM AUTHOR]

In this study, trajectory control of robotic arm which has two degrees of freedom (DOF) is conducted by using the control methods of Proportional-Derivative (PD), Adaptive Neuro Fuzzy System (Anfis), hybrid PD-Anfis and its performance analysis is carried out. In the design of the robot, forward kinematics, inverse kinematics and dynamic equations are used. Firstly, the PD controller is executed, and then the PD controller and Anfis controller are compared applying to a different controller approach with the Anfis of Matlab/Simulink software. The positive and negative sides of the Anfis controller are compared and hybrid PD-Anfis controller method is conducted as a different approach to eliminate the negative sides. While the system constants Kp and Kv are kept constant by the classical PD control method, the output of PD controller is trained with Anfis in the new method and the output value is adjusted according to the error and the change rate of the error. By this way, outputs which have less error rate and which are able to follow the reference better are obtained. [ABSTRACT FROM AUTHOR]