Load Frequency Control (LFC) Strategies in Renewable Energy‐Based Hybrid Power Systems:A Review

The hybrid power system is a combination of renewable energy power plants and conventional energy power plants. This integration causes power quality issues including poor settling times and higher transient contents. The main issue of such interconnection is the frequency variations caused in the hybrid power system. Load Frequency Controller (LFC) design ensures the reliable and efficient operation of the power system. The main function of LFC is to maintain the system frequency within safe limits, hence keeping power at a specific range. An LFC should be supported with modern and intelligent control structures for providing the adequate power to the system. This paper presents a comprehensive review of several LFC structures in a diverse configuration of a power system. First of all, an overview of a renewable energy-based power system is provided with a need for the development of LFC. The basic operation was studied in single-area, multi-area and multi-stage power system configurations. Types of controllers developed on different techniques studied with an overview of different control techniques were utilized. The comparative analysis of various controllers and strategies was performed graphically. The future scope of work provided lists the potential areas for conducting further research. Finally, the paper concludes by emphasizing the need for better LFC design in complex power system environments

Stability Analysis and Design of Variable Step-Size P Algorithm Based on Fuzzy Robust Tracking of MPPT for Standalone/Grid Connected Power System

This research aims to design a modified P&O algorithm for the efficient tracking of maximum power point (MPPT) for standalone and grid-connected systems. The proposed research work modifies the P&O algorithm for the dc-dc converter where the fixed step size P&O algorithm is translated into variable step size with the help of ant colony optimization (ACO) to generate optimal parameters for the PID controller to generate a variable step size in the P&O algorithm. This variable step size is dependent upon the error that is the difference between the generated power and desired power. By doing this it improves the efficiency of the P&O algorithm and its limitations are overcome. Furthermore, the PV is extended to connect with a grid where the inverter is controlled by a fuzzy logic controller (FLC) so that the combined structure of variable P&O and fuzzy helps to achieve MPP efficiently. The robustness of the proposed work is compared with other state-of-the-art controllers to justify the effectiveness of the proposed work. Finally, a stability test of the system is carried out to verify the overall stability of the power system

Inter-markets volatility spillover in U.S. bitcoin and financial markets

This paper investigates the volatility spillover dynamics between U.S. Bitcoin and financial markets from July 19, 2010 to December 29, 2017. Diebold and Yilmaz (2012) volatility spillover index, Barunik, Kocenda, and Vacha (2017) Spillover Asymmetry Measure, and Barunik and Krehlik (2018) frequency connectedness methodologies are applied to investigate the time varying dynamics of volatility spillover among U.S. Bitcoin and financial markets. The findings of the study indicate the presence of low level of integration and contagion between U.S. Bitcoin and financial markets. Asymmetric nature of volatility spillover is also detected. The connectedness among the U.S. Bitcoin and financial markets is found to be concentrated at high frequency, suggesting that markets process information rapidly. Moreover, the turbulence in Bitcoin market will have insignificant effect on U.S. financial markets. This non-contagion nature of Bitcoin markets provides significant risk hedging and diversification benefits for domestic and foreign investors in the U.S

Load Frequency Control (LFC) Strategies in Renewable Energy-Based Hybrid Power Systems: A Review

The hybrid power system is a combination of renewable energy power plants and conventional energy power plants. This integration causes power quality issues including poor settling times and higher transient contents. The main issue of such interconnection is the frequency variations caused in the hybrid power system. Load Frequency Controller (LFC) design ensures the reliable and efficient operation of the power system. The main function of LFC is to maintain the system frequency within safe limits, hence keeping power at a specific range. An LFC should be supported with modern and intelligent control structures for providing the adequate power to the system. This paper presents a comprehensive review of several LFC structures in a diverse configuration of a power system. First of all, an overview of a renewable energy-based power system is provided with a need for the development of LFC. The basic operation was studied in single-area, multi-area and multi-stage power system configurations. Types of controllers developed on different techniques studied with an overview of different control techniques were utilized. The comparative analysis of various controllers and strategies was performed graphically. The future scope of work provided lists the potential areas for conducting further research. Finally, the paper concludes by emphasizing the need for better LFC design in complex power system environments

Improved hybrid sphere decoding algorithm for long horizon finite control set model predictive control of grid-tied inverter

In this paper, the reference tracking and switching loss minimization problem of grid-tied inverters has been formulated as an integer least square (ILS) problem. It is considered an NP-hard and combinatorial problem due to the binary nature of switching status. A novel modification to the traditional non-recursive sphere decoding algorithm is being proposed in this research to address the implementation of long-horizon control with reduced computational burden. The proposed algorithm demonstrates a significant reduction in computation cost for long horizons resulting in energy minimization. The proposed method exploits the state-space model of the system to predict the sector in the space vector two-dimensional plane in which reference voltage could exist, thereby reducing the search space and time to search for the optimal solution. The proposed algorithm optimizes the utilization of controller resources compared to the conventional approach. The algorithm’s performance has been validated through simulations and Hardware in loop verification, for the performance optimization of a three-phase grid-tied inverter coupled using RL filter

Infallibility of the Prophets: A Research Based Analysis

The Research is about the Infallibility of the prophets. Infallibility means Protections form sins. It is a basic belief of the Muslim Ummah that Prophets are saved and protected from sins. They are models for the human being and having a strong character throughout their lives. Qur’an has mentioned the infallibility of the prophets in details and showed that the prophets are innocent and they do not pay attention towards the sins and prohibited acts. A small minority of Muslim scholars have opined that the Prophets might have committed sins of an minor type called zalla, meaning ‘error’ or ‘lapse’, and give some example from their lives Adam, Noah, Abraham and Joseph, [peace be upon them]. Before elaborating their cases, it should be noted that even if we even attribute some errors to the Prophets, they errors are not sins in the meaning of disobedience to God’s Commandments. The Prophets cared to wait for Revelation when they had a question to judge. On rare occasions, however, it happened that they would exercise their own power of reasoning in order to give a judgment as they were the greatest of mujtahids (jurists of the highest rank who can infer laws from the principles established by the Qur’an and the Sunnah). They might sometimes have made mistakes in their judgments or decisions, but such mistakes, which were immediately corrected by God, can never be considered as sins.

Implementation of Image Processing Based Digital Dactylology Converser for Deaf-Mute Persons

Language of signs is usually used by the deaf-mute persons in order to convey their message. But, it becomes very difficult for those who have no knowledge of the sign language. The aim of this research work is to resolve this problem using Digital Dactylology Converser (DOC) which is a device that converts a sign language into voice signal and text message. Primarily a hands gesture is recognised by computer vision program and based on that image a speech and text is played and displayed on the speaker and LCD respectively. Purpose of this device is to make conversation easy between dumb and the normal people around the world. In order to minimize their limitations and enable them to expand their boundaries, this is best suitable device. Experimental results verify the operational accuracy of the device for different users. The proposed device can work well and translates the letters, alphabets to text and soun

Comparison of GPGPU based Robotic Manipulator with other Embedded Controllers

Industrial and robotic controllers have to execute various complex independent tasks repeatedly in real time. In order to implement these algorithms with non-linear equations, massive computational power is required in a motion control system. In this paper, inverse kinematics algorithm is selected as a test algorithm to compare performance of General Purpose Graphics Processing Unit (GPGPU) with other widely used sequential and concurrent controllers. Inverse Kinematics algorithm is implemented sequentially in Arduino Due microcontroller and FPGA is used for concurrent implementation where algorithm is designed in VHDL using combinational division. Execution speeds of these controllers are compared with NVIDIA Quadro K2200 GPU programmed with CUDA Parallel Computing Architecture. Results validated that using computational power of GPU, execution time of large independent tasks is significantly decrease