scholarly journals Comparison of Virtual Synchronous Generator Strategies for Control of Distributed Energy Sources and Power System Stability Improvement

2021 ◽  
Author(s):  
Guilherme Penha da Silva Júnior ◽  
Thiago Figueiredo do Nascimento ◽  
Luciano Sales Barros
Keyword(s):  
Power Systems ◽  
Power System ◽  
Renewable Energy Sources ◽  
Synchronous Generator ◽  
System Stability ◽  
Control Mode ◽  
Voltage Source ◽  
Energy Sources ◽  
And Performance ◽  
Virtual Synchronous Generator

The high integration of distributed generation (DG) system based on renewable energy sources (RES) in the power system requires changes regarding the control mode of these sources with some urgency. Such changes seek to maintain the stability of the power systems. Thus, there is a demand for using control techniques on DGs/RESs that can mitigate the disturbances caused by low inertia and the lack of control over the dispatched powers. As a solution, one can use virtual synchronous generator (VSG) techniques making the voltage  source inverter (VSI) control behave similarly to the traditional synchronous generator (SG). This paper presents a literature review and performance tests for the main VSG topologies used in DGs/RESs: ISE, VSYNC, VISMA and Synchronverter. The implementation of VSG in the DGs/RESs has made possible increase inertia in the grid and, additionally regulate the active and reactive powers separately and bidirectionally. So, it has been possible to meet power system requirements; being able to operation both grid-connected or island-mode, which is ideal for microgrids. The results obtained confirm the literature reports. It was observed that the Synchronverter topology presented advantages over the other VSG topologies.

scholarly journals Obtaining Probability Distribution Laws of Power System Steady-State Mode Parameters

2020 ◽  
Vol 20 (3) ◽  
pp. 41-51
Keyword(s):  
Renewable Energy ◽  
Probability Distribution ◽  
Power Systems ◽  
Power System ◽  
Renewable Energy Sources ◽  
Current Trend ◽  
System Stability ◽  
Energy Sources ◽  
Stable Operation ◽  
Distribution Laws

Stable operation of electrical power systems is one of the crucial issues in the power industry. Current vo­lumes of electricity consumption cause the need to constantly increase the generated capacity, repeatedly modifying and complicating the original circuit. In addition to this, given the current trend towards the use of digital power systems and renewable energy sources, more and more uncertainties difficult to predict by standard mathematical methods appear. Events in the power system are deterministic, i.e. random. Thus, it is difficult to fully assess the system stability, voltage levels, currents, or possible power losses. Finding the probability distribution laws can give us an understanding of all the possible states in which an object can exist. Obtaining them is complicated by the difficulty of accounting for all the correlations between the random arguments of the source data. These laws are necessary to determine the optimal operating modes, the possibility of solving the problem of determining the optimal renewable energy sources installation locations and the required amount of generated energy in a non-deterministic way. The purpose of this article is to test the developed SIBD method for obtaining the full probabilistic characteristics. This method, unlike the Monte Carlo methods, does not use a random sample of initial data, but completely covers the studied functional dependence. The problem was solved using the provisions of probability theory and mathematical statistics, numerical optimization methods in particular. The MATLAB Matpower application package was also used to solve technical computing problems.

scholarly journals Converter-driven Stability Analysis of Power Systems Integrated with Hybrid Renewable Energy Sources

2021 ◽  
Author(s):  
Jianqiang Luo ◽  
Yiqing Zou ◽  
Siqi Bu
Keyword(s):  
Renewable Energy ◽  
Stability Analysis ◽  
Power Systems ◽  
Power System ◽  
Dynamic Models ◽  
Renewable Energy Sources ◽  
Energy Sources ◽  
Power Electronic ◽  
Modal Interaction ◽  
Hybrid Renewable Energy

Various renewable energy sources such as wind power and photovoltaic (PV) have been increasingly integrated into the power system through power electronic converters in recent years. However, power electronic converter-driven stability issues under specific circumstances, for instance, modal resonances might deteriorate the dynamic performance of the power systems or even threaten the overall stability. In this paper, the integration impact of a hybrid renewable energy source (HRES) system on modal interaction and converter-driven stability is investigated in an IEEE 16-machine 68-bus power system. Firstly, an HRES system is introduced, which consists of full converter-based wind power generation (FCWG) and full converter-based photovoltaic generation (FCPV). The equivalent dynamic models of FCWG and FCPV are then established, followed by the linearized state-space modeling. On this basis, converter-driven stability analyses are performed to reveal the modal resonance mechanisms of the interconnected power systems and the modal interaction phenomenon. Additionally, time-domain simulations are conducted to verify effectiveness of dynamic models and support the converter-driven stability analysis results. To avoid detrimental modal resonances, an optimization strategy is further proposed by retuning the controller parameters of the HRES system. The overall results demonstrate the modal interaction effect between external AC power system and the HRES system and its various impacts on converter-driven stability.

scholarly journals Renewable Energy System on Frequency Stability Control Strategy Using Virtual Synchronous Generator

Symmetry ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 1697 ◽  
Author(s):  
Lingling Li ◽  
Hengyi Li ◽  
Ming-Lang Tseng ◽  
Huan Feng ◽  
Anthony S. F. Chiu
Keyword(s):  
Renewable Energy ◽  
Power System ◽  
Large Scale ◽  
Synchronous Generator ◽  
Frequency Stability ◽  
Stability Control ◽  
System Stability ◽  
Generator System ◽  
System Frequency ◽  
Virtual Synchronous Generator

This study constructs a novel virtual synchronous generator system based on a transfer function, and optimizes the parameters of the model by using the improved whale algorithm to improve the frequency control ability of virtual synchronous generator. Virtual synchronous generator technology helps to solve the problem that the integration of large-scale renewable energy generation into the power system leads to the deterioration of system frequency stability. It can maintain the symmetry of grid-connected scale and system stability. The virtual synchronous generator technology makes the inverter to have the inertia and damping characteristics of a synchronous generator. The inverter has the inertia characteristics and damps to reduce the frequency instability of high penetration renewable energy power system. The improved whale algorithm is efficient to find the best combination of control parameters and the effectiveness of the algorithm is verified by microgrid and power system. The results show that the proposed frequency coordination control scheme suppresses the frequency deviation of power system and keep the system frequency in a reasonable range.

scholarly journals Application of Synchrophasor Measurements for Improving Situational Awareness of the Power System

2018 ◽  
Vol 55 (2) ◽  
pp. 3-10
Author(s):  
A. Obushevs ◽  
A. Mutule
Keyword(s):  
Renewable Energy ◽  
Power Systems ◽  
Power System ◽  
Electric Power ◽  
Real Time ◽  
Situational Awareness ◽  
Renewable Energy Sources ◽  
Electric Power System ◽  
Energy Sources ◽  
Scada Systems

Abstract The paper focuses on the application of synchrophasor measurements that present unprecedented benefits compared to SCADA systems in order to facilitate the successful transformation of the Nordic-Baltic-and-European electric power system to operate with large amounts of renewable energy sources and improve situational awareness of the power system. The article describes new functionalities of visualisation tools to estimate a grid inertia level in real time with monitoring results between Nordic and Baltic power systems.

scholarly journals Frequency Control of Large-Scale Interconnected Power Systems via Battery Integration: A Comparison Between the Hybrid Battery Model and WECC Model

2021 ◽  
Author(s):  
Roghieh Abdollahi Biroon ◽  
Pierluigi Pisu ◽  
David Schoenwald
Keyword(s):  
Power Systems ◽  
Power System ◽  
Large Scale ◽  
System Analysis ◽  
Hybrid Control ◽  
Frequency Control ◽  
Renewable Energy Sources ◽  
Control Design ◽  
Energy Sources ◽  
The Stability

The increasing penetration of renewable energy sources in power grids highlights the role of battery energy stor- age systems (BESSs) in enhancing the stability and reliability of electricity. A key challenge with the renewables’, specially the BESSs, integration into the power system is the lack of proper dynamic model for stability analysis. Moreover, a proper control design for the power system is a complicated issue due to its complexity and inter-connectivity. Thus, the application of decentralized control to improve the stability of a large- scale power system is inevitable, especially in distributed energy sources (DERs). This paper presents an optimal distributed hybrid control design for the interconnected systems to suppress the effects of small disturbances in the power system employing utility-scale batteries based on existing battery models. The results show that i) the smart scheduling of the batteries’ output reduces the inter-area oscillations and improves the stability of the power systems; ii) the hybrid model of the battery is more user-friendly compared to the Western electricity coordinating council (WECC) model in power system analysis.

scholarly journals A Feasibility Solution of a Synchronous Generator for Optimisation of the System Power Stability using an Integrated Development Environment of Visual Basic-Excel

2020 ◽  
Vol 9 (3) ◽  
pp. 1261-1268
Keyword(s):  
Power Systems ◽  
Power System ◽  
Digital Simulation ◽  
Synchronous Generator ◽  
Power System Stability ◽  
System Stability ◽  
Development Environment ◽  
Runge Kutta ◽  
Mathematical Techniques ◽  
Computational Resources

Power systems are considered highly non-linear because the environment in which they operate keep changing and hence require iterative mathematical techniques to analyse them. Such changes have a resultant effect on the system`s stability. Fluctuations in parameters are experienced in loads across the networks of the system, generator`s outputs, network topology and other operating parameters. Practically, there is no analytical solution exists for solving the problem of stability. On the other hand, there are techniques available to obtain an acceptable approximate solution of such a problem, known as digital simulation. Runge-kutta method is one of these techniques which has been used broadly as it calculates every step in a sequence of sub-steps. The method relies on a complex mathematical modelling of the synchronous generator with the help of Park-Gorev`s transformation, for the sake of simplicity and intuitiveness the method is used to analyse and study the complex equations of the three-phase synchronous generator. Generally, the system is said to be stable if the opposing forces within it are balanced and at a perfect equilibrium. The aims of this research are to establish the effects of synchronous generator`s design and transient conditions upon power system stability with the help of Embedded Microsoft Excel Sheet based on Power System Stability Analysis (EMES-PSS), using the Runge-Kutta integration method. The study has proved that EMES-PSS can find the limits of Salient and Non-Salient machines stability when changing their essential parameters. The optimisation solutions of the power system stability problem can be achieved by using basic computational resources. The software can also be used on a number of modern tablets e.g., Apple`s tablets.

scholarly journals Quasi-Z-Source Inverter-Based Photovoltaic Power System Modeling for Grid Stability Studies

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 508
Author(s):  
Lluís Monjo ◽  
Luis Sainz ◽  
Juan José Mesas ◽  
Joaquín Pedra
Keyword(s):  
Power Systems ◽  
Power System ◽  
System Modeling ◽  
Power Conversion ◽  
System Stability ◽  
Voltage Source ◽  
Voltage Source Converter ◽  
Stability Problems ◽  
Sensitivity Studies ◽  
And Control

Quasi-Z-source inverters (qZSIs) are becoming a powerful power conversion technology in photovoltaic (PV) power systems because they allow energy power conversion in a single stage operation. However, they can cause system resonances and reduce system damping, which may lead to instabilities. These stability problems are well known in grid-connected voltage source converter systems but not in quasi-Z-source inverter (qZSI)-based PV power systems. This paper contributes with Matlab/Simulink and PSCAD/EMTDC models of qZSI-based PV power systems to analyze transient interactions and stability problems. These models consider all power circuits and control blocks of qZSI-based PV power systems and can be used in sensitivity studies on the influence of system parameters on stability. PV power system stability is assessed from the proposed models. The causes of instabilities are analyzed from numerical simulations and possible solutions are proposed.

scholarly journals Challenges of High Renewable Energy Sources Integration in Power Systems—The Case of Croatia

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 1047
Author(s):  
Ninoslav Holjevac ◽  
Tomislav Baškarad ◽  
Josip Đaković ◽  
Matej Krpan ◽  
Matija Zidar ◽  
...  
Keyword(s):  
Renewable Energy ◽  
Power Systems ◽  
Power System ◽  
System Integration ◽  
Renewable Energy Sources ◽  
Current Situation ◽  
Electric Power System ◽  
Energy Sources ◽  
Wind Integration ◽  
Inertial Response

This paper presents a high-level overview of the integration of renewable energy sources (RES), primarily wind and solar, into the electric power system (EPS) in Croatia. It presents transmission system integration aspects for the particular case of this country. It explains the current situation and technical characteristics of the current conventional generation units and currently installed wind energy capacities. Based on the current situation future development scenario is determined and used to evaluate the impacts of the wide-scale integration of renewables. Grid connections aspects, power balancing, market participation, and inertia reduction aspects are considered. Furthermore, some specifics of both solar and wind integration are discussed identifying problems and potential solutions. Primarily through the provision of the inertial response of both solar and wind and through better forecasting of wind production. Finally, the outlook for the Croatian power system is given, that will most probably double its RES capacity in the coming 3-year period and a certain level of investments and changes of current operational practices will need to be provided.

scholarly journals New Coordinated Tuning of SVC and PSSs in Multimachine Power System Using Coyote Optimization Algorithm

2021 ◽  
Vol 13 (6) ◽  
pp. 3131
Author(s):  
Tawfik Guesmi ◽  
Badr M. Alshammari ◽  
Yasser Almalaq ◽  
Ayoob Alateeq ◽  
Khalid Alqunun
Keyword(s):  
Power Systems ◽  
Power System ◽  
Objective Function ◽  
Time Domain ◽  
Optimization Algorithm ◽  
Optimization Problem ◽  
System Stability ◽  
Electromechanical Oscillations ◽  
And Performance ◽  
Nonlinear Time Domain

This paper presents a new approach for coordinated design of power system stabilizers (PSSs) and static VAR compensator (SVC)-based controller. For this purpose, the design problem is considered as an optimization problem whose decision variables are the controllers’ parameters. Due to nonlinearities of large, interconnected power systems, methods capable of handling any nonlinearity of power networks are mostly preferable. In this regard, a nonlinear time domain based objective function is used. Then, the coyote optimization algorithm (COA) is employed for solving this optimization problem. In order to ensure the robustness and performance of the proposed controller (COA-PSS&SVC), the objective function is evaluated for various extreme loading conditions and system configurations. To show the contribution of the coordinated controllers on the improvement of the system stability, PSSs and SVC are optimally designed in individual and coordinated manners. Moreover, the effectiveness of the COA-PSS&SVC is assessed through comparison with other controllers. Nonlinear time domain simulation shows the superiority of the proposed controller and its ability in providing efficient damping of electromechanical oscillations.

Sign in / Sign up

Export Citation Format

Share Document