scholarly journals Power flow and faults analysis of a hybrid DC Microgrid : PV system and wind energy

2021 ◽  
Author(s):  
◽  
Musawenkosi Lethumcebo Thanduxolo Zulu
Keyword(s):  
Renewable Energy ◽  
Power System ◽  
Wind Energy ◽  
Load Distribution ◽  
Power Flow ◽  
Fault Analysis ◽  
Energy Sources ◽  
Pv System ◽  
Dc Microgrid ◽  
Dc Line

Rural electrification has become a very important means of improving the standard of living of rural dwellers, a process which also helps in the electrification of remote and isolated regions. Presently, the electrification of such regions can be achieved through the use of renewable energy. The use of renewable energy sources such as PV and wind energy is gaining popularity as the solution to achieving the electrification of rural areas, such as the use of the microgrid, which can be in the form of an AC or DC microgrid. The DC microgrid can be used to connect distributed energy resources and its energy storage is considered to be an economical system to meet consumer demand due to its benefits, namely environmental friendliness, reliability and good performance in load distribution. The power system may experience many faults when transferring power via overhead transmission lines to the load. When these faults occur, it is important to detect the location and isolate the part that had experienced the fault quickly, without de-activating the whole microgrid. The main aim of this study was to conduct a power flow and faults analysis on a hybrid DC microgrid model with battery storage. The hybrid energy sources for the DC microgrid are the PV system and wind energy system. Firstly, this research conducted a power flow analysis for the hybrid DC microgrid. Secondly, a fault analysis was carried out on the system and both the power flow and the fault analysis were formulated through implementation in a MATLAB/Simulink environment under various conditions in order to ascertain the stability and reliability of the system. Various MATLAB/Simulations were carried out, including the DC single-line-ground fault and DC line-line fault and are analysed in a designed hybrid DC microgrid power system. The results showed that DC line-to-line and DC line-to-ground faults lead to the imbalance of DC voltage, which is difficult to re-balance and stabilize in the system after the existence of these faults. When these faults occurred in the system, there was immense fluctuation and unsteadiness of output load power delivered to consumers. Moreover, wind-generated power on the generation side was severely affected. Based on the results and analysis of those results, the hybrid DC microgrid is seen as a satisfactory and optimum concept for the generation and transmission of power for rural and isolated area electrification, i.e. it can provide power to remote areas that cannot be reached by the national grid. The study revealed, based on the analysis of results, that it has an effective response under fault conditions. Results for a hybrid DC microgrid revealed that high quality of power is experienced in load distribution. Also based on the results, when DC faults occurs there is disturbance to output.

scholarly journals Improvement of bus voltage profiles of Nigerian power network in the presence of Static Synchronous Compensator (STATCOM) and Doubly Fed Induction Generator (DFIG)

2020 ◽  
Vol 39 (1) ◽  
pp. 228-237
Author(s):  
I.B. Anichebe ◽  
A.O. Ekwue
Keyword(s):  
Renewable Energy ◽  
Stability Analysis ◽  
Power System ◽  
Power Flow ◽  
Voltage Stability ◽  
Reactive Power ◽  
Renewable Energy Sources ◽  
Load Flow ◽  
Energy Sources ◽  
Power Network

Frequent blackouts and unstable supply of electricity show that the  voltage instability problem has been one of the major challenges facing the power system network in Nigeria. This study investigates the voltage stability analysis of the Nigerian power network in the presence of renewable energy sources; FACTS device is used as a voltage controller. A 330kV, 28-bus power system network was studied using the PSS/E software-based Newton-Raphson load-flow technique. The results show that 10 out of the 28 buses had voltages lying below the statutory limit of 0.95 ≤ 1.05 p.u. The application of STATCOM and DFIG devices on two of the weakest buses restored the voltages to acceptable statutory limits. The total active and reactive power losses were reduced to 18.76% and 18.82% respectively. Keywords: Voltage stability analysis; Integration of renewable energy sources; FACTS controllers, Reactive Power, Power Flow.

scholarly journals A Progressive Period Optimal Power Flow for Systems with High Penetration of Variable Renewable Energy Sources

Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2815
Author(s):  
Zongjie Wang ◽  
C. Lindsay Anderson
Keyword(s):  
Renewable Energy ◽  
Power System ◽  
Real Time ◽  
Power Flow ◽  
Optimal Power Flow ◽  
Renewable Energy Sources ◽  
Wind Farms ◽  
Energy Sources ◽  
Power System Operations ◽  
Optimal Power

Renewable energy sources including wind farms and solar sites, have been rapidly integrated within power systems for economic and environmental reasons. Unfortunately, many renewable energy sources suffer from variability and uncertainty, which may jeopardize security and stability of the power system. To face this challenge, it is necessary to develop new methods to manage increasing supply-side uncertainty within operational strategies. In modern power system operations, the optimal power flow (OPF) is essential to all stages of the system operational horizon; underlying both day-ahead scheduling and real-time dispatch decisions. The dispatch levels determined are then implemented for the duration of the dispatch interval, with the expectation that frequency response and balancing reserves are sufficient to manage intra-interval deviations. To achieve more accurate generation schedules and better reliability with increasing renewable resources, the OPF must be solved faster and with better accuracy within continuous time intervals, in both day-ahead scheduling and real-time dispatch. To this end, we formulate a multi-period dispatch framework, that is, progressive period optimal power flow (PPOPF), which builds on an interval optimal power flow (IOPF), which leverages median and endpoints on the interval to develop coherent coordinations between day-ahead and real-time period optimal power flow (POPF). Simulation case studies on a practical PEGASE 13,659-bus transmission system in Europe have demonstrated implementation of the proposed PPOPF within multi-stage power system operations, resulting in zero dispatch error and violation compared with traditional OPF.

scholarly journals An Integrated Multiport Dc – Dc Converter for Renewable Energy Applications

2019 ◽  
Vol 9 (1) ◽  
pp. 7023-7028
Keyword(s):  
Renewable Energy ◽  
Wind Energy ◽  
Power Flow ◽  
Renewable Energy Sources ◽  
Power Converter ◽  
Energy Output ◽  
Energy Sources ◽  
Present System ◽  
Compact Structure ◽  
Flow Management

As conventional energy sources are steadily depleting n nature due to human activities, renewable energy sources are the need of the hour. Renewable energy source delivers environmental friendly, sustainable power. Due to the intermittent nature of these source, the power produced cannot be used directly by the consumers. So the output power is conditional to meet the grid requirements by using semiconductor devices.In the present system, wind energy output is coupled with back to back power converter and solar energy output with dc to ac converter. The output from the two systems are separately interfaced with the power grid. This has the disadvantages of higher components count, increased cost and inefficient power flow management. The proposed system consists of four ports among which one port is for solar point input, one port is for wind energy input, one bi-directional battery port and an isolated load port. Zero voltage switching is adopted for all main switches in the converter. The integrated four port converter has the advantages of interfacing two sources and controlling them with low cost, compact structure that allow and intelligent power flow management between the household users, the electric distribution grid and the distributed generation units. This converter provides the facilities to combine two or more generation sources. Solar power and wind power are given as input to the two input ports of the converter. The converters use four main switches for this conversion. The output voltage will be a DC voltage. This voltage can be used to derive any DC load or can be converted to AC voltage using inverter to drive an AC load

scholarly journals A Review on Fuzzy-GA based Controller for Power Flow Control in Grid Connected PV System

2017 ◽  
Vol 7 (1) ◽  
pp. 125
Author(s):  
Raghu Thumu ◽  
K. Harinadha Reddy
Keyword(s):  
Renewable Energy ◽  
Power Quality ◽  
Power Flow ◽  
Reactive Power ◽  
Renewable Energy Sources ◽  
Energy Sources ◽  
Pv System ◽  
Pv Array ◽  
Reactive Power Flow ◽  
Photo Voltaic

<p>Now-a-days Renewable Energy Sources became an alternative to meet the increasing load demand because they are environmental friendly and also available abundant in nature. Among the Renewable Energy Sources, the Photo Voltaic (PV) System is gaining more attention due abundant availability of solar energy. The Maximum Power Point Tracking Technique is used to extract maximum power from the Photo Voltaic (PV) Array. When there is a need to transfer bulk amount of power from PV Array to Power Grid, the power quality issues, especially the real and reactive power flow problems, are a major concern. In this paper a novel control technique was proposed to control the power flow and to deal with power quality issues that arise when PV Array is integrated with power grid. It consists of a Fuzzy-GA based Cascaded Controller fed Flexible AC Transmission System device, namely Unified Power Flow Controller, for effective control of real and reactive power flow in grid connected photovoltaic system. The output of the Fuzzy Logic Controller is a control vector which is fine tuned by using Genetic Algorithm approach.</p>

scholarly journals The Control Principles of the Wind Energy Based DC Microgrid

2018 ◽  
Vol 55 (2) ◽  
pp. 28-36
Author(s):  
G. Zaleskis ◽  
I. Rankis
Keyword(s):  
Renewable Energy ◽  
Wind Energy ◽  
Renewable Energy Sources ◽  
Energy Sources ◽  
Stable Operation ◽  
Dc Microgrid ◽  
Wind Energy Conversion ◽  
Wind Generators ◽  
Effective Use ◽  
Technical Solutions

Abstract According to the strategical objectives of the use of the renewable energy sources, it is important to minimise energy consumption of conventional power grid by effective use of the renewable energy sources and provi-ding stable operation of the consumers. The main aim of research is to develop technical solutions that can provide effective operation of the wind generators in the small power DC microgrids, which also means wind energy conversion at as wider generator speed range as possible.

scholarly journals Solar and Wind Power Forecasting with Optimal ARIMA Parameters

2018 ◽  
Vol 7 (1.8) ◽  
pp. 201
Author(s):  
M Veda Swaroop ◽  
P Linga Reddy
Keyword(s):  
Renewable Energy ◽  
Power System ◽  
Wind Energy ◽  
Renewable Energy Sources ◽  
Green Energy ◽  
Energy Sources ◽  
National Renewable Energy Laboratory ◽  
Wind Energy Generation ◽  
Forecasting Method ◽  
The Cost

The solar and wind renewable energy sources are gaining popularity to encourage green energy into the power system. The cost of generation of solar and wind energy sources are decreasing and competing with conventional coal-based generation. Therefore, it is very important to integrate these renewable sources into the power system. Integrating Solar and wind energy sources require to solve the uncertainty problem. Both the solar and wind energy generation is uncertain and not controllable. In this paper, sliding window optimal ARIMA forecasting algorithm is proposed to solve the uncertainty associated with solar and wind sources. The proposed forecasting method is used on the data collected from National Renewable Energy Laboratory website.  

scholarly journals Inertia Theory Frequency Dynamic Analysis and Control of Power System with High Proportion of Renewable Source

2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Badar ul Islam ◽  
Zuhairi Baharudin ◽  
Parameshwari Kattel
Keyword(s):  
Renewable Energy ◽  
Power System ◽  
Power Plants ◽  
Renewable Energy Sources ◽  
Frequency Stability ◽  
Test System ◽  
Energy Sources ◽  
Power Imbalance ◽  
Pv System ◽  
System Inertia

Power plant emissions are a major cause of pollution in the environment. This necessitates the progressive replacement of conventional power plants with renewable energy sources. Changes in the quotas for conventional generating and renewable energy sources present new issues for modern power networks for example photovoltaic and wind turbines are replacing conventional power plants, which do not add to system inertia and due to the earth’s diurnal cycle and weather conditions. Solar radiations are not consistent all through the day, and photovoltaic (PV) generation is sometimes insufficient to meet the power requirement of the shifting local load. The amount of inertia in the power system, as well as the action of adjustable frequency reserves and the amount of power imbalance, all have an impact on frequency stability. As a result, estimating power system inertia and assessing frequency response are required so that necessary actions can be taken to assure frequency stability. In this way, the system frequency, power, and voltage stability are the major issues when high proportion of renewables are added. In this paper, we explained estimating power system inertia-related frequency problems. The approach account for the frequency and voltage fluctuations that occur after a disturbance and estimate the system’s total inertia constant as well as its overall power imbalance. The anticipated technique based on computational intelligence is used to analyze frequency responses from simulations of a test system under various circumstances on SIMULINK and focuses on the standalone PV system is critical for controlling it. As a result, the modelling of a PV system, battery, and generator using analogous circuits is discussed. As a matter of fact, maximum power should be harvested from a PV array to increase its efficiency that is depicted from the result outcomes of this research.

Sign in / Sign up

Export Citation Format

Share Document