Search results for: T. Enayaty Ahangar
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4

Search results for: T. Enayaty Ahangar

4 Upgrading of Old Large Turbo Generators

Authors: M. Shadmand, T. Enayaty Ahangar, S. Kazemi

Abstract:

Insulation system of electrical machineries is the most critical point for their durability. Depending on generator nominal voltage, its insulation system is designed. In this research, a new stator insulation system is designed by new type of mica tapes which will consequently enables us to decrease the nominal ground-wall insulation thickness for the same voltage level. By keeping constant the slot area, it will be possible to increase the copper value in stator bars which will consequently able us to increase the nominal output current of turbo-generator. This will affect the cooling capability of machinery to some extent. But by considering the thermal conductivity of new insulating system which is improved, it is possible to increase the output power of generator up to 6% more. This research is done practically on a 200 MVA and 15.75 kV turbo-generators which its insulating system is Resin Rich (RR).

Keywords: insulation system, resin rich, VPI, upgrading

Procedia PDF Downloads 466
3 Improving Load Frequency Control of Multi-Area Power System by Considering Uncertainty by Using Optimized Type 2 Fuzzy Pid Controller with the Harmony Search Algorithm

Authors: Mehrdad Mahmudizad, Roya Ahmadi Ahangar

Abstract:

This paper presents the method of designing the type 2 fuzzy PID controllers in order to solve the problem of Load Frequency Control (LFC). The Harmony Search (HS) algorithm is used to regulate the measurement factors and the effect of uncertainty of membership functions of Interval Type 2 Fuzzy Proportional Integral Differential (IT2FPID) controllers in order to reduce the frequency deviation resulted from the load oscillations. The simulation results implicitly show that the performance of the proposed IT2FPID LFC in terms of error, settling time and resistance against different load oscillations is more appropriate and preferred than PID and Type 1 Fuzzy Proportional Integral Differential (T1FPID) controllers.

Keywords: load frequency control, fuzzy-pid controller, type 2 fuzzy system, harmony search algorithm

Procedia PDF Downloads 235
2 Variation of Clinical Manifestations of COVID-19 Over Time of Pandemic

Authors: Mahdi Asghari Ozma, Fatemeh Aghamohammadzadeh, Mahin Ahangar Oskouee

Abstract:

In late 2019, the people of the world were involved with a new infection by the coronavirus, named SARS-COV-2 (COVID-19), which disseminated around the world quickly. This infection has the ability to affect various systems of the body, including respiratory, gastrointestinal, urinary, and hematology, which can be transmitted by various body samples in different ways. To control this fast-transmitted infection by preventing its transmission to other people, rapid diagnosis is vital, which can be done by examining the patient's clinical symptoms and also using various serological, molecular, and radiological methods. Symptoms caused by COVID-19 in patients include fever, cough, sore throat, headache, fatigue, shortness of breath, loss of taste or smell, skin rash, myalgia, and conjunctivitis. These clinical features were appearing gradually in different time periods from the onset of the infection, and patients showed varied and new symptoms at different times, which show the variety of symptoms over time during the spread of the infection.

Keywords: COVID-19, diagnosis, symptom, variation, novel coronavirus

Procedia PDF Downloads 50
1 Improvement of the Robust Proportional–Integral–Derivative (PID) Controller Parameters for Controlling the Frequency in the Intelligent Multi-Zone System at the Present of Wind Generation Using the Seeker Optimization Algorithm

Authors: Roya Ahmadi Ahangar, Hamid Madadyari

Abstract:

The seeker optimization algorithm (SOA) is increasingly gaining popularity among the researchers society due to its effectiveness in solving some real-world optimization problems. This paper provides the load-frequency control method based on the SOA for removing oscillations in the power system. A three-zone power system includes a thermal zone, a hydraulic zone and a wind zone equipped with robust proportional-integral-differential (PID) controllers. The result of simulation indicates that load-frequency changes in the wind zone for the multi-zone system are damped in a short period of time. Meanwhile, in the oscillation period, the oscillations amplitude is not significant. The result of simulation emphasizes that the PID controller designed using the seeker optimization algorithm has a robust function and a better performance for oscillations damping compared to the traditional PID controller. The proposed controller’s performance has been compared to the performance of PID controller regulated with Particle Swarm Optimization (PSO) and. Genetic Algorithm (GA) and Artificial Bee Colony (ABC) algorithms in order to show the superior capability of the proposed SOA in regulating the PID controller. The simulation results emphasize the better performance of the optimized PID controller based on SOA compared to the PID controller optimized with PSO, GA and ABC algorithms.

Keywords: load-frequency control, multi zone, robust PID controller, wind generation

Procedia PDF Downloads 275