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. K E Y W O R D S doubly fed induction generator, matrix converter, model predictive control, observer, power quality, reduced-order extended Kalman filter 1 | INTRODUCTION Matrix topology is a converter that can provide AC to AC power conversion and consists of bidirectional nine switches that are connected to each other. The output voltage is generated directly from the input voltage due to does not have large energy storage elements such as inductor or capacitor between input and output. Also, due to the switches are bidirectional,

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.

A novel isolated 7‐level (7L) multi‐level inverter (MLI) topology for grid‐connected medium and high voltage power applications is presented in this paper. The topology consists of two isolated transformers with different winding ratio and four switches connected to a single‐phase grid. This topology provides a great advantage over conventional MLIs by reducing passive and active components to allowing a 7L output voltage. Moreover, model predictive control (MPC) method is implemented to 7L‐MLI to generate gate signals of switches and ensure capacitor voltage balancing and grid connection. Performance of proposed topology has been confirmed by in‐depth analysis under simulation and laboratory setup with existing studies. Experimental results of a 1.5 kW 220 Vrms prototype are presented to support the simulation results. The prototype shows that the harmonic results match the limits of the IEC 61000‐3‐2 standard and show a better performance for grid connection and capacitor voltage balancing than conventional ones.

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.

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