26 research outputs found

    Estimation of Electrical Parameters of the Induction Machine Steady State Model Using Nameplate Data and Hunger Game Search Algorithm

    Get PDF
    In this paper, the Hunger Games Search (HGS) optimization algorithm is used to estimate the electrical parameters of the induction machine steady state model. Induction machine nameplate data is used as input to the proposed algorithm. The performance of the proposed method is confirmed by comparing the output characteristics obtained by estimating the motor parameters including torque, current and power factor in the steady state model of the induction machine with the values provided by the manufacturer. In addition, by evaluating and comparing the results of the proposed method with the results of previous research, it is shown that the proposed algorithm is a very effective and accurate method for the acceptable estimation of induction machine parameters

    Introducing a New Hybrid Method to Reduce BLDC Motor Torque Ripple, Based on Predictive Control and Quasi Z-Source Converter

    Get PDF
    The commutation torque ripple adversely affects the performance of the six-phase inverter of the BLDC motor with trapezoidal back EMF and creates vibration and noise for industrial applications. In this paper, the motor model is obtained in non-commutation times and during the commutation period, and according to that, a suitable method to reduce the torque ripple, by equalizing the slope of the current disconnected from the motor and the slope of the current connected to the motor during commutation, is presented. At low speeds, torque ripple is reduced using predictive pulse width modulation technique. With this method, the duty cycle of the switch involved in the commutation is predicted and applied to the switch during the commutation intervals. At high speeds, this reduction is done using quasi z-source converter and selector circuit. The quasi z-source converter and the selector circuit increase the input voltage of the inverter during commutation intervals and increase its value to four times the back EMF voltage of the motor, thus reducing the torque ripple at high speeds. The theoretical and analytical results are verified using the simulations performed in the PLECS software

    Tuning the Properties of the Osmium Nitrido Group in TpOs(N)X 2

    No full text

    Alkane Oxidation by Osmium Tetroxide

    No full text

    Marital Satisfaction amongst Parents of Children with Attention Deficit Hyperactivity Disorder and Normal Children

    No full text
    Objective: The aim of this study was to compare marital satisfactionbetween parents of children with attention deficit hyper activity disorder (ADHD) and parents of normal children.Methods: In this study we have selected 400 parents (200 parents of children with ADHD and 200 parents of normal children), whose children age range was 6-18 years. Data were collected using Enrich marital satisfaction Questionnaire, Kiddie Schedule for Affective Disorders and Schizophrenia Present and Lifetime Version (K-SADS-PL) and Conner’s Questionnaire (parent and self-report forms). For data analysis, SPSS software17, bivariate χ2- test, and independent t- test were used.Results: The mean of marital satisfaction in parents of normal children was higher than parents of ADHD children. In the bivariate χ2- test, the p value was less than 0.05, and the obtained t was more than the table-t (1.96), so it can be assumed that there is a significant difference between parents of normal children and those with ADHD children in their marital satisfaction. The level of marital satisfaction (strongly agree level) was 2.8% lower among parents of ADHD children compared to parents of normal children.Conclusions: Findings indicate that parents with ADHD children have lower level of marital satisfaction than parents with normal children
    corecore