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Comparison the Performance of the Dynamic Voltage Restorer Based on PI, Fuzzy Logic, and Fuzzy Neural Controller
Issue:
Volume 5, Issue 1, June 2021
Pages:
1-11
Received:
26 March 2021
Accepted:
12 April 2021
Published:
26 April 2021
Abstract: The Dynamic Voltage Restorer (DVR) is one of the most efficient and effective custom power devices in protecting the sensitive equipment against voltage sag and voltage harmonics due to; lower cost, smaller size and dynamic response. The inverter is the core of the DVR and it directly affects the performance of the DVR, incorrect injection or delay in the process would be dangerous to sensitive loads. The major functions of the DVR controller are, detection of voltage disturbances events in the system, calculation of the compensating voltage and generation the reference signal for the PWM to trigger the voltage source inverter. PI controller and fuzzy logic controller has been compared with the proposed fuzzy neural optimized fuzzy logic controller in correcting the sag problems and mitigating the harmonics distortion with linear and non-linear loads. Fuzzy Neural optimized Fuzzy Logic controller is the most efficient in improving the performance of the Dynamic Voltage Restorer in compensating any kind of voltage variations and reducing the voltage Total Harmonic Distortion (THD) by enhancing an injection capability of the DVR which is highly influenced by a control algorithm employed. The system is simulated in MATLAB and results confirm the validity and feasibility.
Abstract: The Dynamic Voltage Restorer (DVR) is one of the most efficient and effective custom power devices in protecting the sensitive equipment against voltage sag and voltage harmonics due to; lower cost, smaller size and dynamic response. The inverter is the core of the DVR and it directly affects the performance of the DVR, incorrect injection or delay...
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The Relationship Between Business Environment and Happiness with Corporate Profitability
Issue:
Volume 5, Issue 1, June 2021
Pages:
12-20
Received:
19 February 2021
Accepted:
16 April 2021
Published:
29 April 2021
Abstract: Business and investment in any area requires the provision of an appropriate and secure institutional environment. One of the factors that helps to expand businesses and increase corporate profits is the right business environment. Avoiding complicated administrative bureaucracy, lending and credit, proper international trade, and the ease of obtaining the necessary permits will be helpful in this regard. On the other hand, businesses can perform better in a happy and stress-free environment. Happiness is an emotional state characterized by feelings of joy, satisfaction, contentment, and fulfillment. While happiness has many different definitions, it is often described as involving positive emotions and life satisfaction. The purpose of the present study is to investigate the relationship between the business environment and happiness indicators with corporate profitability. For this purpose, 175 top companies in the world from 2013 to 2018 that were profitable among the top 500 companies each year were selected as the statistical population. World Happiness annual report, Doing Business annual reports, and Fortune site were used to collect the data. Also the data analysis was done according to the panel data method using Stata software. The results shows that in general, there is a positive relationship between business environment and happiness indicators corporate profitability.
Abstract: Business and investment in any area requires the provision of an appropriate and secure institutional environment. One of the factors that helps to expand businesses and increase corporate profits is the right business environment. Avoiding complicated administrative bureaucracy, lending and credit, proper international trade, and the ease of obtai...
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Fuzzy Neural Optimized Fuzzy Logic Controller Based Dynamic Voltage Restorer for Power Quality Improvement with Non-linear Loads
Issue:
Volume 5, Issue 1, June 2021
Pages:
21-32
Received:
26 March 2021
Accepted:
22 April 2021
Published:
30 April 2021
Abstract: Recently a large attention has been focused on a power quality domain due to: disturbances caused by non-linear loads, Increase in number of electronic devices and growth of renewable energy sources. Power quality measures the fitness of electric power transmitted from generation to industrial, domestic and commercial consumers. At least 50% of power quality problems are of voltage quality type. In power system voltage sags, voltage distortion introduced by harmonics, and asymmetrical voltage are considered to be the most severe affecting power quality, because both utilities and consumers are affected by these disturbances. Different methods introduced to solve power problems but the custom power devices are the most effective and efficient methods, one of which is the use of the Dynamic Voltage Restorer (DVR). The main objectives of this research are to achieve more accuracy in compensating the voltage variations and reducing the total harmonics distortion (THD) to acceptable limits. Most of the researchers applied the control strategies to compensate the voltage disturbances in critical load but did not focus on the objective of reducing the total harmonics distortion (THD). In many sensitive loads such as, airport lighting system, medical equipment, auxiliary plant of power system, and adjustable speed drives., the level of the (THD) is more important, this research focuses on mitigating the harmonics to less than 3%. An adaptive controller like fuzzy neural optimized fuzzy logic controller is proposed to improve the performance of the DVR in injecting the required voltage to restore the load voltage to its nominal value under different voltage variations which are created by MATLAB/SIMULINK program for a period of 0.15s from 0.8s and kept till 0.95s.
Abstract: Recently a large attention has been focused on a power quality domain due to: disturbances caused by non-linear loads, Increase in number of electronic devices and growth of renewable energy sources. Power quality measures the fitness of electric power transmitted from generation to industrial, domestic and commercial consumers. At least 50% of pow...
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