Kala Meah

Comparative Evaluation of HVDC and HVAC Transmission Systems

Alternating current (AC) is the main driving force in the industries and residential areas, but for the long transmission line (more than 400 miles) AC transmission is more expensive than that of direct current (DC). Technically, AC transmission line control is more complicated because of the frequency. DC transmission does not have these limitations, which has led to build long HVDC transmission lines over the last 40 years. HVDC technology made possible to transfer bulk power over long distances. This paper presents a comparative evaluation of HVDC and HVAC transmission systems.

Genetic evolving ant direction particle swarm optimization algorithm for optimal power flow with non-smooth cost functions and statistical analysis

Abstract This paper presents an evolving ant direction particle swarm optimization algorithm for solving the optimal power flow problem with non-smooth and non-convex generator cost characteristics. In this method, ant colony search is used to find a suitable velocity updating operator for particle swarm optimization and the ant colony parameters are evolved using genetic algorithm approach. To update the velocities for particle swarm optimization, five velocity updating operators are used in this method. The power flow problem is solved by the Newton–Raphson method. The feasibility of the proposed method was tested on IEEE 30-bus, IEEE 39-bus and IEEE-57 bus systems with three different objective functions. Several cases were investigated to test and validate the effectiveness of the proposed method in finding the optimal solution. Simulation results prove that the proposed method provides better results compared to classical particle swarm optimization and other methods recently reported in the literature. An innovative statistical analysis based on central tendency measures and dispersion measures was carried out on the bus voltage profiles and voltage stability indices.

Simple Fuzzy Self-tuning PI Controller for Multi-terminal HVDC Transmission Systems

Abstract This paper describes fuzzy logic-based self-tuning controller parameters for the rectifier side current regulators and inverter side gamma regulators in a multi-terminal high-voltage direct current (MTDC) transmission system. A four-terminal MTDC system is considered, with the detailed modeling of converters, transformers, source impedances, transmission lines, and filters. Simulations are conducted using MATLAB/SIMULINK® to generate transient responses. The simulation results using a fuzzy self-tuning proportional-integral (PI) controller and a fixed-parameter PI controller are compared. The transient simulation studies presented reveal the superior performance of the fuzzy self-tuning PI controller over the fixed-parameter PI controller in the MTDC transmission systems.

Simulation study of the CIGRE HVDC benchmark model with the WSCC nine-bus power system network

This paper presents a simulation study of the CIGRE high voltage direct current (HVDC) benchmark transmission system with the Western system coordinating council (WSCC) 3-machine, 9-bus power system network. The CIGRE HVDC benchmark system is embedded between generator-two and generator-three of the WSCC system to conduct the simulation. A three phase to ground fault on the AC side of the inverter is applied to study system responses such as settling time after the fault is cleared and the relative load angles.

Rapid Control Prototyping of a Permanent Magnet DC Motor Drive System using dSPACE and Mathworks Simulink

Prototyping is the key step in the manufacturing industry to save time and effort. Successful prototyping needs efficient processes and systems that integrate all necessary development steps. dSPACE offers an efficient rapid control prototyping process for any industry dealing with feedback control. The objective of this paper is to demonstrate a well-documented procedure of rapid control prototyping of a permanent magnet DC (PMDC) motor drive for speed control using dSPACE and Mathworks Simulink. The combined tools of Simulink and dSPACE provide the means for modeling the controller in software and applying it to the actual hardware via a digital signal processing board. This paper presents a comparison and analysis between the simulation results and dSPACE/ actual hardware results, which agreed with each other except for some minor differences.

Wind Energy Resources in Wyoming and Simulation for Existing Grid Connection

Many wind turbines are connected to power systems in the U.S. in recent years in order to reduce the negative environmental impacts of conventional electricity generation and promote the green energy initiative. This paper presents potential wind energy resources in Wyoming and the simulation for an existing grid connection. The wind data and the potential wind power were analyzed and the wind turbine was selected according to the results of analysis. Then the performance of the wind turbine incorporating in power network was simulated using MATLAB/Simulink for steady state and fault conditions. Finally cost benefit assessment and environmental impacts were evaluated

Simulation study of the Frontier Line as a multi-terminal HVDC system

This paper presents a simulation study of the proposed Frontier line from Wyoming to California through Utah and Nevada as a multi-terminal high voltage direct current (HVDC) transmission system. A four-terminal HVDC link is modeled with one terminal in each state. Various faults are simulated at different locations of the transmission link to observe the dynamic performance of the system. Results from the simulation study show that a multi-terminal HVDC link is technically feasible from Wyoming to California.

Short and medium term solutions for the current electricity crisis in Bangladesh

Bangladesh has had problems with electricity distribution for many years. The distribution system in Bangladesh is facing tremendous pressure from industrial and residential users to maintain a regular supply. The Bangladesh Power Distribution Board (BPDB) manages the situation using the load shading technique. Load shedding is now impractical as living standards and electric load characteristics have changed over the years. Modern household and office equipment require electricity and after an outage turn back on automatically, creating high demand when electricity comes back on after a long period of load shedding. Short-term load management techniques are discussed in this paper. This paper also presents alternative medium-term solutions for the electricity crisis in Bangladesh.

The Role of Wyoming's Energy in Solving National Electricity Crisis

Recent electric power shortages in various parts of the US stimulated a peak on generation capacity additions during the first three years of this new century. Most of the newly added units are fired by natural gas, a clean but expensive energy resource. The rapid increase in the use of natural gas makes its price ever increasing and volatile. Coal-fired plants are expected to be more promising for providing cheaper electricity in the near future. Coal will continue to be the primary energy source in electricity generation at least through 2030. Wyoming is the largest coal producing state and one of the largest in natural gas production in the US, but local utilization is extremely low. In addition to exporting raw energy resources, Wyoming could help the nation to solve its electrical energy crisis better by exporting energy directly using high voltage DC (HVDC) lines. The current electrical energy situations of the US and Wyoming are examined and some transmission schemes are proposed in this study. Economic analysis of the proposed schemes is also performed

Investigation on Fuzzy Logic-Based Self-Tuning Current Controller Applications in HVDC Links

This paper describes the effect of different defuzzification methods (DFMs) and membership functions (MFs) on the fuzzy logic-based self-tuning current controller applications in an HVDC link. The OGRE HVDC Benchmark system and control features are modeled using the SimPowerSystem toolbox and the available blocks in the MATLAB/SIMULINKreg. The fuzzy logic-based self-tuning controller is designed using the fuzzy logic toolbox in the MATLABreg. A comparative study is conducted between the fixed-gain controller and the fuzzy tuning controllers. This paper also presents the effect of the number of rules on the fuzzy logic-based self-tuning controller in an HVDC link. The results reveal that fuzzy tuned PI controller recovers the system from the faults faster than the traditional PI controller with fewer oscillations, and consecutively has less commutation failures.