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Direct torque control (DTC) of five-phase PMSMs has been investigated in many literatures. Besides many advantages of this method, large harmonic currents is one the major drawbacks of this scheme. Space vector modulation (SVM) methods have been applied to DTC algorithm to eliminate this problem. But it should be mentioned that SVM methods have complicated calculations. This paper proposes a simple scheme not only uses the DTC method based hysteresis comparators and maintain its simplicity, but eliminates the large harmonic currents. Also, the five-phase PMSM is fed by a three-phase to five-phase matrix converter (MC). Lack of bulky dc-link capacitor and controllable input power factor are some of advantages of MCs. Therefore, the presented method uses the advantages of MC and DTC method and also eliminates the large harmonic currents problem. [ABSTRACT FROM PUBLISHER]

The Indirect Matrix Converter (IMC) concept has been gaining recognition as a promising circuit alternative in recent years. An IMC has separate line and load side converters. Each switching period of line side converter is split into two portions. In each portion, the IMC is equivalent to a conventional inverter. Thus, output voltage can be obtained through applying a kind of space vector PWM to the load side converter. Conventional space vector pulse width modulation (CSVPWM) employs conventional switching sequence, which divides the zero vector time equally between two zero states in each modulation cycle. If a double edge CSVPWM used in each portion, each switch of the load side converter would have a switching frequency twice the sampling frequency. Therefore, bus-clamping PWM (BCPWM) techniques which use only one zero state in each modulation cycle can be used to reduce the switching frequency. [ABSTRACT FROM PUBLISHER]

Concepts of Micro-Grids are proposed to address primarily various issues related to integration of small scale renewable and electricity supply reliability. Micro-grids are Low Voltage networks that usually operate interconnected with the main Medium Voltage network but, in case of emergency, can run autonomously. In such networks Renewable Energy Sources (RES) are foreseen to have rather high penetration mainly photovoltaics and small scale Wind Turbines. In this paper, the electronic infrastructure of micro-grid is expressed. Then discussed the reasons for its complexity and the possibility of reducing the elements of electronic circuits are investigated. The reason for this is in order to compact DC micro-grid system for electrification to places like villages. This document gives Technical and economic comparison that is the reason for the brief electronic infrastructure of DC micro-grid. Simulation in Matlab Simulink is used to show the effectiveness of this method. [ABSTRACT FROM PUBLISHER]

Complex circuitry of electronic infrastructure of compact smart micro grids with multiple renewable energy sources feeding the loads using parallel operation of inverters acts as a deterrent in developing such systems. Parallel Inverters is one of the best methods to provide great load power. One way of briefing electronic infrastructure of micro grids, use parallel driver circuit focusing on bootstrap techniques. But so far research has been done in this area that if fault occurs in the switches what happens and will provide the reliability of the driver circuit? In this paper, first the parallel inverter and its driver circuit are studied and in the next section, their behavior will be analyzed when the switch is erroneous. Digital Simulation in Matlab Simulink is used to show the proposed solutions to this type of behavior and to avoid errors leading to other parts of the system. [ABSTRACT FROM PUBLISHER]

Micro-grid is one of new conceptual power systems for smooth installation of many distributed generations (DGs). While most of the micro-grids adopt ac distribution as well as conventional power systems, dc micro-grids are proposed and researched for the good connection with dc output type sources such as photovoltaics (PV), fuel cell, and secondary battery. In this paper, the electronic infrastructure of micro-grid is expressed. Then discussed the reasons for its complexity and the possibility of reducing the elements of electronic circuits are investigated. The reason for this is in order to compact dc micro-grid system for electrification to places like villages. [ABSTRACT FROM PUBLISHER]