Claim Missing Document
Check
Articles

Found 4 Documents
Search

Induction Motor Speed Control Using Indirect Z-source Matrix Converter with PSO-PI Controller under Various Break Conditions Majid Salim; Mohammad Sarvi
International Journal of Power Electronics and Drive Systems (IJPEDS) Vol 3, No 1: March 2013
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Since induction motors are preferred over direct current machines in the view of cost and simplicity, they have widely been used in industry. In this paper, the speed of the three-phase induction motor has been controlled using an indirect z-source matrix converter. The method used for this purpose is flux control keeping the V/f ratio and regulating slippage. The effect of flux changes and reference velocity in this method has been taken into consideration and various electric break methods on the motor have been studied accordingly. Coefficients of PI controllers have been obtained in the proposed system for desirable response by PSO Algorithm. The proposed system with the respective converter has been simulated in SIMULINK environment using the information of an induction machine by MATLAB Software. The results show to using the proposed system and indirect z-source matrix converter, appropriate velocity and desirable torque are obtained in a short time. DOI: http://dx.doi.org/10.11591/ijpeds.v3i1.1783
A Fuzzy Model for Ni-Cd Batteries Mohammad Sarvi; Masoud Safari
IAES International Journal of Artificial Intelligence (IJ-AI) Vol 2, No 2: June 2013
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (405.532 KB)

Abstract

The batteries models found in the literature are based mainly on mathematical descriptions of physical, chemical, and electrochemical properties which are difficult to determine. This paper presents new fuzzy based model for Nickel Cadmium (Ni-Cd) batteries. The main advantage of the proposed models is that, the proposed model is able to predict battery output voltage without knowledge of numerous factors. Inputs of the proposed model are battery current and state of charge while battery voltage is selected as the output. To check the accuracy of the proposed models, simulations results are compared with the measured battery data at different charge current as well as many other battery models for a 7Ah, size F, Ni-Cd battery. Simulated shows good agreements with measured data. The advantage of fuzzy model is that for modeling by fuzzy method experimental data isn’t needed. The proposed models can apply for modeling of other batteries types.DOI: http://dx.doi.org/10.11591/ij-ai.v2i2.1784
Determination of Fault Location and Type in Distribution Systems using Clark Transformation and Neural Network Mohammad Sarvi; S. M. Torabi
International Journal of Applied Power Engineering (IJAPE) Vol 1, No 2: August 2012
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (238.947 KB) | DOI: 10.11591/ijape.v1.i2.pp75-86

Abstract

In this paper, an accurate method for determination of fault location and fault type in power distribution systems by neural network is proposed. This method uses neural network to classify and locate normal and composite types of faults as phase to earth, two phases to earth, phase to phase. Also this method can distinguish three phase short circuit from normal network position. In the presented method, neural network is trained by αβ space vector parameters. These parameters are obtained using clarke transformation. Simulation results are presented in the MATLAB software. Two neural networks (MLP and RBF) are investigated and their results are compared with each other. The accuracy and benefit of the proposed method for determination of fault type and location in distribution power systems has been shown in simulation results.
A Fuzzy-PD Controller to Improve the Performance of HVDC System Mohammad Sarvi; Majid Keshmiri
International Journal of Applied Power Engineering (IJAPE) Vol 2, No 2: August 2013
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (640.15 KB) | DOI: 10.11591/ijape.v2.i2.pp79-88

Abstract

In this paper, a fuzzy self adjustment controller has been designed for using in control of a high voltage direct current (HVDC) system. Fuzzy logic method via fuzzy rules based on simple experimental logical proofs, selects the coefficient of PD controller. In order to investigate the performance and accuracy of the proposed control method, a Cigre system is considered and analyzed. The proposed fuzzy - PD controller is compared with conventional PD controller. To achieve this purpose, the operations of designed controllers are investigated for different conditions. Fuzzy controllers used to control of inverter and rectifier converters, improve significantly system responses and performances as well as DC power recovering, especially on hard faults. The HVDC control system with fuzzy controllers in soft faults and variations with small amplitude, are similar conventional control, but on hard faults and variation with large amplitude, the performances are improved in compare with conventional control.