Journal of Majlesi Journal of Mechatronic Systems
Volume:8 Issue: 2, June 2019

This paper discuss improving the quality conditions for feeding grids using four-quadrant chopper in dc-link for a 12pulse diode bridge rectifier variable speed drive system VSDS. This includes reducing the ripple and crest factors for voltage and current waves in dc-link. Variable speed drive system with a 12-pulse diode bridge rectifier has been modeled and simulated; the results demonstrating the ability of the proposed chopper to improve power quality in modern industrial facilities were discussed.

This paper presents a modelling and sliding mode control (SMC) of a doubly fed induction generator (DFIG) integrated into wind turbine system (WTS) for independent control of reactive and active stator power. For a comparative study, the independent control of reactive and active stator power is ensured in the first step by fuzzy sliding mode controller (FSMC) and the second step by fuzzy second order sliding mode controller (FSOSMC). Finally, the performance of the system is tested and compared by simulation in terms of robustness and reference tracking based on Matlab / Simulink software

This paper studies the design of feedback controllers to achieve generalized projective synchronization (GPS) between two fractional derivative order hyperchaotic Lu systems (similar), and between hyperchaotic Cai system and fractional-order hyperchaotic Lu system (dissimilar). First, new sliding surface is defined for GPS of fractional-order Lu-Lu and Lu-Cai systems. Then the results of the GPS achieved in this article is proved using Lyapunov stability theorem. Without using Lyapunov exponents, the active feedback control method to achieve GPS of fractional-order hyperchaotic Lu-Lu and Cai-Lu is calculated. Performance of the proposed method is shown, using numerical simulations

DC-DC Converter, for Integrated Buck Boost Series Parallel Fly-Back Converter (IBBSPFC) a single MOSFET Switch is used. This IBBSPFC can achieve high or low voltages by buck and boost process. The pass through a filter capacitances be able to be low thus to facilitate film capacitor can be used. Buck-boost converter can operate in Buck mode and Boost mode with continuous conduction mode by the inductor and capacitors. In this design, regulation and reliability of the converter improves when the capacitors are linked in series among the main winding of isolation transformer and the power transfer capability is improved by parallel connection of the isolation transformer with capacitor. By this IBBSPFC can increase and decrease of volt conversion without any transformer losses is obtained for different duty cycles. Therefore, this is beneficial for higher efficiency and reliability and the cost of the System can be reduced by using Fast recovery diodes, inductor and capacitors. By Conversion of 24V input to 50VOutput in continuous conduction mode (CCM) under 100W output power is obtained

This paper proposes the mitigation of grid voltage disturbances using a 7-level Packed U Cells (PUC7) based dynamic voltage restorer (DVR) solution. Which regulates the injection of the compensation voltage in series and synchronism with the grid during the voltage disturbance events, the auxiliary capacitor voltage, while controlling the PUC7 output current. A Seven-Level Packed U Cells (PUC7) inverter is composed of a smaller number of IGBTs and circuitry compared to similar structures. A voltage balancing controller is designed to apply the seven levels of the inverter; this is done by regulate the output voltage of the DC capacitors to a desired value in order to obtain seven levels at the output of the inverter. This feature enables the structure to be used to compensate for the power quality of power distribution networks. Nearest Level Control (NLC) in the inverter is used to create the desired waveform. The In-Phase control method is selected to control the proposed DVR and use the synchronous reference frame (SRF) method to detect the network voltage fluctuations. To verify and validate the proposed DVR performance, simulations are carried out in the MATLAB / SIMULINK software environment, and the results indicate the optimal performance and desirability of the proposed DVR to compensate for the voltage sag, swell and flicker power distribution grids. Theoretical analysis and simulation results are given to show the high performance of the proposed solution