The increasing amounts of customer-owned Distributed Energy Resources (DERs) limit the control and visibility of local Independent System Operators (ISOs) and utility operators. Most of these resources are non-curtailable and subject to several aggregation guidelines for wholesale participation. These units cannot be decoupled from the Transmission-Distribution (T-D) interface and have a direct impact on the economics and reliability of the grid. This paper reports the results of a study that investigated realistic dispatch conditions from a production and power flow co-simulation environment with increased behind-the-meter DER resources. The objectives of this study include: 1) understanding steady-state and transient voltage response of the system at the local T-D interface, 2) analyzing impacts on switching operations, 3) studying the system-wide frequency response of the Western Interconnection, and 4) examining scenarios that provide insight into the type of control strategies that best benefit local ISO and utility operations from a reliability perspective.
What is DERMS ? Distributed Energy Resources Management System
What is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management System
This document describes a flexible software-based distributed energy management system (DEMS) designed to investigate how controllable distributed energy units (CDEs) can be aggregated and integrated into the electric grid. The DEMS uses a hierarchical agent-based model to control different CDEs, including a wind turbine, combined heat and power plant, electric vehicle charging station, and industrial load. An experiment was conducted using the DEMS to demonstrate how it can aggregate these CDEs in different communication configurations to meet a secondary frequency control signal while maximizing profit from energy generation. Results showed the DEMS was able to successfully control the CDEs to closely track the required active power output.
This document summarizes a review of 16 solar PV benefit and cost studies conducted between 2005-2013. Key insights include:
- No single study comprehensively evaluated all benefits and costs of distributed solar PV, though most acknowledged additional sources that were difficult to quantify.
- There was significant variation in estimated values across studies due to differences in local contexts, assumptions, and methodologies.
- Methodological differences that most affected results were analysis resolution/granularity, cost/benefit categories considered, and individual value calculation approaches.
- There was general agreement on estimating energy value but less consensus on other values like grid support services and unmonetized benefits.
- Important gaps remain around quantifying distribution system impacts, grid support
IRJET- Voltage Stability, Loadability and Contingency Analysis with Optimal I...IRJET Journal
This document discusses contingency analysis and optimal placement of renewable distributed generators (RDGs) using continuation power flow analysis to improve voltage stability and loadability. It presents a methodology to determine the optimal location and mix of different RDG technologies (solar, wind, fuel cells) on the IEEE 9-bus test system using the Power System Analysis Toolbox (PSAT). Reactive power performance indices are calculated for different line contingencies to identify critical buses. The results show that optimally placing RDGs can enhance voltage stability and increase the maximum loadability point compared to the base case without RDGs.
Value of Distributed Energy Resources (VDER) PresentationDavid Katz
In support of Reforming the Energy VisionLink opens in new window - close new window to return to this page., the New York State Public Service Commission established a mechanism to transition to a new way to compensate distributed energy resources (DER), like solar power. This mechanism, called the Value of Distributed Energy Resources (VDER), replaces net energy metering (net metering or NEM).
This presentation was presented on February 8. 2018
IRJET- A Comparative Study of Economic Load Dispatch Optimization MethodsIRJET Journal
This document presents a comparative study of different optimization methods for solving the economic load dispatch (ELD) problem in power systems. The ELD problem involves minimizing generation costs while meeting demand, and is formulated as a non-linear optimization problem with constraints. Various conventional and evolutionary algorithms have been used to solve ELD, but more recently bio-inspired algorithms like flower pollination algorithm and Jaya optimization have shown better performance. The paper evaluates these nature-inspired algorithms and compares their results for the ELD problem to demonstrate their effectiveness.
This document summarizes research on approaches to managing congestion in deregulated electricity markets. It reviews various congestion management methods that have been proposed, including nodal pricing, price area congestion management, available transfer capability based approaches, using thyristor controlled phase shifting transformers, and flexible AC transmission systems devices. It also discusses optimization techniques that have been applied to congestion management problems, such as genetic algorithms and particle swarm optimization. The document provides examples of research on applying these different congestion management methods and optimization techniques to address transmission network congestion issues in deregulated power systems.
Demand response (DR) resources can provide various services to wholesale electricity markets including energy, capacity, and ancillary services depending on the market rules. DR is seen as an important tool for reliable grid operations and preventing market power issues. Federal regulations and funding aim to improve the role of DR by requiring comparable treatment of DR and generation in markets and supporting smart grid demonstration projects. Individual ISO/RTO markets define different products DR can provide and have requirements for metering and communications to enable participation.
What is DERMS ? Distributed Energy Resources Management System
What is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management SystemWhat is DERMS ? Distributed Energy Resources Management System
This document describes a flexible software-based distributed energy management system (DEMS) designed to investigate how controllable distributed energy units (CDEs) can be aggregated and integrated into the electric grid. The DEMS uses a hierarchical agent-based model to control different CDEs, including a wind turbine, combined heat and power plant, electric vehicle charging station, and industrial load. An experiment was conducted using the DEMS to demonstrate how it can aggregate these CDEs in different communication configurations to meet a secondary frequency control signal while maximizing profit from energy generation. Results showed the DEMS was able to successfully control the CDEs to closely track the required active power output.
This document summarizes a review of 16 solar PV benefit and cost studies conducted between 2005-2013. Key insights include:
- No single study comprehensively evaluated all benefits and costs of distributed solar PV, though most acknowledged additional sources that were difficult to quantify.
- There was significant variation in estimated values across studies due to differences in local contexts, assumptions, and methodologies.
- Methodological differences that most affected results were analysis resolution/granularity, cost/benefit categories considered, and individual value calculation approaches.
- There was general agreement on estimating energy value but less consensus on other values like grid support services and unmonetized benefits.
- Important gaps remain around quantifying distribution system impacts, grid support
IRJET- Voltage Stability, Loadability and Contingency Analysis with Optimal I...IRJET Journal
This document discusses contingency analysis and optimal placement of renewable distributed generators (RDGs) using continuation power flow analysis to improve voltage stability and loadability. It presents a methodology to determine the optimal location and mix of different RDG technologies (solar, wind, fuel cells) on the IEEE 9-bus test system using the Power System Analysis Toolbox (PSAT). Reactive power performance indices are calculated for different line contingencies to identify critical buses. The results show that optimally placing RDGs can enhance voltage stability and increase the maximum loadability point compared to the base case without RDGs.
Value of Distributed Energy Resources (VDER) PresentationDavid Katz
In support of Reforming the Energy VisionLink opens in new window - close new window to return to this page., the New York State Public Service Commission established a mechanism to transition to a new way to compensate distributed energy resources (DER), like solar power. This mechanism, called the Value of Distributed Energy Resources (VDER), replaces net energy metering (net metering or NEM).
This presentation was presented on February 8. 2018
IRJET- A Comparative Study of Economic Load Dispatch Optimization MethodsIRJET Journal
This document presents a comparative study of different optimization methods for solving the economic load dispatch (ELD) problem in power systems. The ELD problem involves minimizing generation costs while meeting demand, and is formulated as a non-linear optimization problem with constraints. Various conventional and evolutionary algorithms have been used to solve ELD, but more recently bio-inspired algorithms like flower pollination algorithm and Jaya optimization have shown better performance. The paper evaluates these nature-inspired algorithms and compares their results for the ELD problem to demonstrate their effectiveness.
This document summarizes research on approaches to managing congestion in deregulated electricity markets. It reviews various congestion management methods that have been proposed, including nodal pricing, price area congestion management, available transfer capability based approaches, using thyristor controlled phase shifting transformers, and flexible AC transmission systems devices. It also discusses optimization techniques that have been applied to congestion management problems, such as genetic algorithms and particle swarm optimization. The document provides examples of research on applying these different congestion management methods and optimization techniques to address transmission network congestion issues in deregulated power systems.
Demand response (DR) resources can provide various services to wholesale electricity markets including energy, capacity, and ancillary services depending on the market rules. DR is seen as an important tool for reliable grid operations and preventing market power issues. Federal regulations and funding aim to improve the role of DR by requiring comparable treatment of DR and generation in markets and supporting smart grid demonstration projects. Individual ISO/RTO markets define different products DR can provide and have requirements for metering and communications to enable participation.
Investigation of the challenges in establishing plug and play low voltage dc ...PromiseBeshel
A research proposal to improve the stability, efficiency, and reliability problems of low voltage DC microgrids from a communication control strategy point of view.
Power distribution planning_reference_book__second_edition__power_engineering...sushrut p
This document provides a summary of the contents and structure of the second edition of the book "Power Distribution Planning Reference Book" by H. Lee Willis. Some key points:
- The book has more than doubled in content from the first edition, with roughly 70% being new material, in order to address modern challenges in power distribution planning.
- New challenges include a greater focus on reliability management, business priorities of reducing costs while maintaining service quality, and managing aging infrastructure.
- The book is organized into four parts that cover resources for distribution planning, detailed reviews of technical distribution system aspects, planning tools and technologies, and the planning process.
- Several new chapters have been added addressing topics like reliability-
IRJET- Design and Simulation of Solar PV DC Microgrid for Rural ElectrificationIRJET Journal
This document summarizes a research paper that analyzes and designs a DC microgrid system for rural electrification in India. Key points:
1) The microgrid uses distributed solar PV generation, with maximum power point tracking converters connecting the solar panels. Fanout nodes distribute power to local clusters of homes, and power management units at each home regulate usage and integrate battery storage.
2) Experimental results from a 400W prototype demonstrate the steady-state operation and stability of the system when power from the solar source is varied. The microgrid is able to maintain a stable distributed voltage while enabling power sharing between components.
3) Calculations estimate the levelized cost of electricity for the microgrid design would be lower
A hybrid approach for ipfc location and parameters optimization for congestio...eSAT Journals
Abstract
The deregulated power system operation with competitive electricity market environment has been created many challenging tasks to the system operator. The competition with strategic bidding has been resulted for randomness in generation schedule, load withdrawal and power flows across the network. The economic efficiency of electricity market is mainly dependent on network support. In the event of congestion, it is required to alter the base case market settlement and hence the economic inefficiency in terms of congestion cost can occur. In order to anticipate congestion and its consequences in operation, this paper has been considered Interline Power Flow Controller (IPFC).This article proposed a tactical approach for optimal location and then its parameters in Decoupled Power Injection Modeling (DPIM) are optimized using Gravitational Search Algorithm (GSA). The case studies are performed on IEEE 30-bus test system and the results obtained are validating the proposed approach for practical implementations.
Keywords: Deregulated power system, competitive electricity market, congestion management, IPFC, Gravitational Search Algorithm (GSA)
This document describes a methodology for optimally allocating Unified Power Flow Controller (UPFC) devices in a power transmission system using multi-objective optimal power flow and genetic algorithms. The objectives are to maximize social welfare by minimizing generation costs while also minimizing branch overloading. A multi-objective optimal power flow formulation is presented with two objective functions - minimizing total generation costs and minimizing an exponential branch loading function. A genetic algorithm is then used to determine the optimal number and locations of UPFC devices to place on the system to minimize the two objectives simultaneously. The approach is demonstrated on the IEEE 30-bus test system.
Design methodology of smart photovoltaic plant IJECEIAES
In this article, we present a new methodology to design an intelligent photovoltaic power plant connected to an electrical grid with storage to supply the laying hen rearing centers. This study requires a very competent design methodology in order to optimize the production and consumption of electrical energy. Our contribution consists in proposing a robust dimensioning synthesis elaborated according to a data flow chart. To achieve this objective, the photovoltaic system was first designed using a deterministic method, then the software "Homer" was used to check the feasibility of the design. Then, controllers (fuzzy logic) were used to optimize the energy produced and consumed. The power produced by the photovoltaic generator (GPV) is optimized by two fuzzy controllers: one to extract the maximum energy and another to control the batteries. The energy consumed by the load is optimized by a fuzzy controller that regulates the internal climate of the livestock buildings. The proposed control strategies are developed and implemented using MATLAB/Simulink.
1. The document provides an introduction to wind energy in India and Madhya Pradesh, including the history and components of wind turbines.
2. It discusses the power sector reforms that began in Madhya Pradesh in the 1990s due to financial crises, which included separating generation, transmission, and distribution functions and encouraging private sector participation.
3. The key components of a horizontal axis wind turbine are described as the rotor, blades, nacelle, low and high speed shafts, gearbox, brake, generator, anemometer, and tower.
Introducing LQR-fuzzy for a dynamic multi area LFC-DR modelIJECEIAES
It is well known that Load Frequency Control (LFC) model plays a vital role in electric power system design and operation. In the literature, much research works has stated on the advantages and realization of DR (Demand Response), which has proved to be an important part of the future smart grid. In an interconnected power system, if a load demand changes randomly, both frequency and tie line power varies. LFC-DR model is tuned by standard controllers like PI, PD, PID controllers, as they have constant gains. Hence, they are incapable of acquiring desirable dynamic performance for an extensive variety of operating conditions and various load changes. This paper presents the idea of introducing a DR control loop in the traditional Multi area LFC model (called LFC -DR) using LQR- Fuzzy Logic Control. The effect of DR-CDL i.e. (Demand Response Communication Delay Latency) in the design is also considered and is linearized using Padé approximation. Simulation results shows that the addition of DR control loop with proposed controller guarantees stability of the overall closed-loop LFC-DR system which effectively improves the system dynamic performance and is superior over a classical controller at different operating scenarios.
Centralized voltage control in medium voltage distribution networks with dist...davidtrebolle
The growing shares of distributed generation represent new challenges to distribution grids operation regarding estimation and control of voltage profile along medium and low voltage feeders. This fact leads distribution networks to become active distribution systems in order to increase monitoring and control in medium and low voltage networks. In addition, Distributed Generation (DG) may be a new resource to provide a voltage control ancillary service to Distribution System Operators (DSOs). This issue is one of the main objectives of PRICE-GDI project. This paper presents analyses carried out within this project in order to determine the benefits of voltage control provided by DG.
The new regulatory framework which is being stated in
European Network Codes includes some requirements
for DSOs regarding voltage control. This paper analyses the impact of these requirements on voltage control provided by DG
The need for enhanced power system modelling techniques and simulation toolsPower System Operation
The transition to a clean energy future requires
thorough understanding of increasingly complex
interactions between conventional generation, network
equipment, variable renewable generation technologies
(centralised and distributed), and demand response.
Secure and reliable operation under such complex
interactions requires the use of more advanced power
system modelling and simulation tools and techniques.
Conventional tools and techniques are reaching their
limits to support such paradigm shifts.
The paper highlights the need for an Active System Management (ASM) of distribution networks as a key tool for the efficient and secure integration of a high share of Distributed Energy Resources (DER). The paper provides technical and regulatory recommendations that mainly focus on distributed generation but are also largely applicable to flexible loads, electric vehicles and storage.
A NOVEL CONTROL STRATEGY FOR POWER QUALITY IMPROVEMENT USING ANN TECHNIQUE FO...IJERD Editor
The proposed system presents power-control strategies of a Micro grid-connected hybrid generation
system with versatile power transfer. This hybrid system allows maximum utilization of freely available
renewable energy sources like wind and photovoltaic energies. For this, an adaptive MPPT algorithm along with
standard perturbs and observes method will be used for the system.
The inverter converts the DC output from non-conventional energy into useful AC power for the
connected load. This hybrid system operates under normal conditions which include normal room temperature
in the case of solar energy and normal wind speed at plain area in the case of wind energy. However, designing
an optimal micro grid is not an easy task, due to the fact that primary energy carriers are changeable and
uncontrollable, as is the demand. Traditional design and optimization tools, developed for controlled power
sources, cannot be employed here. Simulation methods seem to be the best solution.
The dynamic model of the proposed system is first elaborated in the stationary reference frame and
then transformed into the synchronous orthogonal reference frame. The transformed variables are used in
control of the voltage source converter as the heart of the interfacing system between DG resources and utility
grid. By setting an appropriate compensation current references from the sensed load currents in control circuit
loop of DG, the active, reactive, and harmonic load current components will be compensated with fast dynamic
response, thereby achieving sinusoidal grid currents in phase with load voltages, while required power of the
load is more than the maximum injected power of the DG to the grid. In addition, the proposed control method
of this paper does not need a phase-locked loop in control circuit and has fast dynamic response in providing
active and reactive power components of the grid-connected loads.
Power system planning & operation [eceg 4410]Sifan Welisa
The document discusses power load forecasting and substation planning. It explains that accurate load forecasting is important for power system planning and operation. Several load forecasting methods are described, including those based on historical load data, economic factors, and standardized load curves. Load forecasts can be short, medium, or long-term. The document also discusses factors to consider in substation planning and design, such as location, equipment requirements, and configuration. Feasibility studies are important for assessing potential hydroelectric and substation projects.
Power System Reliability Assessment in a Complex Restructured Power SystemIJECEIAES
The basic purpose of an electric power system is to supply its consumers with electric energy as parsimoniously as possible and with a sensible degree of continuity and quality. It is expected that the solicitation of power system reliability assessment in bulk power systems will continue to increase in the future especially in the newly deregulated power diligence. This paper presents the research conducted on the three areas of incorporating multi-state generating unit models, evaluating system performance indices and identifying transmission paucities in complex system adequacy assessment. The incentives for electricity market participants to endow in new generation and transmission facilities are highly influenced by the market risk in a complex restructured environment. This paper also presents a procedure to identify transmission deficiencies and remedial modification in the composite generation and transmission system and focused on the application of probabilistic techniques in composite system adequacy assessment
This research presents a method for reliability assessment considering the 23MVA, 230/15 kV
transformer through two 15 kV outgoing transmission lines at Debre Markos substation. It also goes further to
include 139 low voltage 15/0.4 kV distribution transformers. The total load connected to the 15 kV feeders are
varies between 0.33255 and 6.3185 MW. A composite system adequacy and security assessment is done using
Monte Carlo simulation. The basic data and the topology used in the analysis are based on the Institution of
Electrical and Electronics Engineers - Reliability Test System and distribution system for bus two of the IEEEReliability
Bus bar Test System. The reliability indices SAIDI, SAIFI, CAIDI, EENS, AENS, ASAI, ASUI, and
expected interruption costs are being assessed and considered. Distribution system reliability information was
obtained from actual data for systems operating in Ethiopia Electric Utility office and Debre Markos substation
recorded data and online SCADA system.
1) A distributed energy future will require distribution utilities to plan, operate, and innovate in new ways to integrate distributed energy resources and accommodate two-way power flows on the grid.
2) This changing paradigm encompasses seven dimensions including two-way power flows, local integration and balancing of resources, functional control of distributed resources, and new business models.
3) Distribution utilities will need to develop new planning approaches to handle issues like two-way power flows, energy storage and electric vehicles, demand response, and renewable energy forecasting. They will also need to collect and analyze more data from smart grids and distributed sensors.
Loss Reduction by Optimal Placement of Distributed Generation on a Radial feederIDES Editor
Due to the increasing interest on renewable sources
in recent times, the studies on integration of distributed
generation to the power grid have rapidly increased. In order
to minimize line losses of power systems, it is crucially
important to define the location of local generation to be placed.
Proper location of DGs in power systems is important for
obtaining their maximum potential benefits. This paper
presents analytical approaches to determine the optimal
location to place a DG on radial systems to minimize the power
loss of the system. Simulation results are given to verify the
proposed analytical approaches.
A Review on Optimization Techniques for Power Quality Improvement using DSTAT...ijtsrd
This document summarizes a research paper that proposes using a neural network approach to optimize techniques for improving power quality using a DSTATCOM (Distribution Static Compensator). It begins by introducing common power quality issues like voltage sags, swells, and harmonics. It then discusses different custom power devices used to address these issues, focusing on the DSTATCOM. The paper proposes a control algorithm using a backpropagation neural network to extract reference currents and control the DSTATCOM for reactive power compensation, load balancing, and voltage regulation. Simulation results showed the DSTATCOM was able to satisfactorily compensate for different types of loads using this neural network approach.
This document introduces the concepts of Distributed Flexible AC Transmission Systems (D-FACTS) as an alternative approach to realizing cost-effective power flow control. Specifically:
1) It proposes distributed series impedance (DSI) and distributed static series compensator (DSSC) devices that can be clamped onto existing power lines to dynamically and statically control power flow.
2) DSI and DSSC work by varying the impedance of power lines using small modules containing reactive elements and single turn transformers, without requiring a break in the transmission line.
3) This distributed approach could provide higher performance and lower cost active power flow control compared to conventional FACTS devices, through scalability,
Single core configurations of saturated core fault current limiter performanc...IJECEIAES
Economic growth with industrialization and urbanization lead to an extensive increase in power demand. It forced the utilities to add power generating facilities to cause the necessary demand-generation balance. The bulk power generating stations, mostly interconnected, with the penetration of distributed generation result in an enormous rise in the fault level of power networks. It necessitates for electrical utilities to control the fault current so that the existing switchgear can continue its services without upgradation or replacement for reliable supply. The deployment of fault current limiter (FCL) at the distribution and transmission networks has been under investigation as a potential solution to the problem. A saturated core fault current limiter (SCFCL) technology is a smart, scalable, efficient, reliable, and commercially viable option to manage fault levels in existing and future MV/HV supply systems. This paper presents the comparative performance analysis of two single-core SCFCL topologies impressed with different core saturations. It has demonstrated that the single AC winding configuration needs more bias power for affecting the same current limiting performance with an acceptable steady-state voltage drop contribution. The fault state impedance has a transient nature, and the optimum bias selection is a critical design parameter in realizing the SCFCL applications.
Economic Impacts of Behind the Meter Distributed Energy Resources on Transmis...Power System Operation
The increasing penetration of customer-owned Distribution Energy Resources (DERs) will have an impact on the economics that govern market operation. Visibility and control of local Independent System Operators (ISOs) over these resources are currently restricted or available in some form of aggregation. Additionally, non-curtailable resources pose a serious problem while balancing the market with eminent risks of over-generation and added congestion to the system. This study attempts to decouple the model at the Transmission-Distribution interface and demonstrate the following: 1) economic implications of such resources under two control strategies, 2) aspects of market dynamics affected by several DER penetration levels, 3) Potential benefits of increased ISO visibility beyond the Transmission-Distribution(T-D) interface.
This document summarizes a study on distributed energy resources (DER). It discusses how increased DER is changing power systems and potential reliability issues. DER provides alternatives to large central plants but can impact transmission systems. The document recommends:
1) Collecting and sharing DER location, type, and performance data across transmission and distribution systems to support modeling.
2) Modeling DER in bulk power system studies if significant impacts are expected based on location and output.
3) Avoiding netting of DER with load and instead aggregating or explicitly modeling DER based on penetration levels.
Investigation of the challenges in establishing plug and play low voltage dc ...PromiseBeshel
A research proposal to improve the stability, efficiency, and reliability problems of low voltage DC microgrids from a communication control strategy point of view.
Power distribution planning_reference_book__second_edition__power_engineering...sushrut p
This document provides a summary of the contents and structure of the second edition of the book "Power Distribution Planning Reference Book" by H. Lee Willis. Some key points:
- The book has more than doubled in content from the first edition, with roughly 70% being new material, in order to address modern challenges in power distribution planning.
- New challenges include a greater focus on reliability management, business priorities of reducing costs while maintaining service quality, and managing aging infrastructure.
- The book is organized into four parts that cover resources for distribution planning, detailed reviews of technical distribution system aspects, planning tools and technologies, and the planning process.
- Several new chapters have been added addressing topics like reliability-
IRJET- Design and Simulation of Solar PV DC Microgrid for Rural ElectrificationIRJET Journal
This document summarizes a research paper that analyzes and designs a DC microgrid system for rural electrification in India. Key points:
1) The microgrid uses distributed solar PV generation, with maximum power point tracking converters connecting the solar panels. Fanout nodes distribute power to local clusters of homes, and power management units at each home regulate usage and integrate battery storage.
2) Experimental results from a 400W prototype demonstrate the steady-state operation and stability of the system when power from the solar source is varied. The microgrid is able to maintain a stable distributed voltage while enabling power sharing between components.
3) Calculations estimate the levelized cost of electricity for the microgrid design would be lower
A hybrid approach for ipfc location and parameters optimization for congestio...eSAT Journals
Abstract
The deregulated power system operation with competitive electricity market environment has been created many challenging tasks to the system operator. The competition with strategic bidding has been resulted for randomness in generation schedule, load withdrawal and power flows across the network. The economic efficiency of electricity market is mainly dependent on network support. In the event of congestion, it is required to alter the base case market settlement and hence the economic inefficiency in terms of congestion cost can occur. In order to anticipate congestion and its consequences in operation, this paper has been considered Interline Power Flow Controller (IPFC).This article proposed a tactical approach for optimal location and then its parameters in Decoupled Power Injection Modeling (DPIM) are optimized using Gravitational Search Algorithm (GSA). The case studies are performed on IEEE 30-bus test system and the results obtained are validating the proposed approach for practical implementations.
Keywords: Deregulated power system, competitive electricity market, congestion management, IPFC, Gravitational Search Algorithm (GSA)
This document describes a methodology for optimally allocating Unified Power Flow Controller (UPFC) devices in a power transmission system using multi-objective optimal power flow and genetic algorithms. The objectives are to maximize social welfare by minimizing generation costs while also minimizing branch overloading. A multi-objective optimal power flow formulation is presented with two objective functions - minimizing total generation costs and minimizing an exponential branch loading function. A genetic algorithm is then used to determine the optimal number and locations of UPFC devices to place on the system to minimize the two objectives simultaneously. The approach is demonstrated on the IEEE 30-bus test system.
Design methodology of smart photovoltaic plant IJECEIAES
In this article, we present a new methodology to design an intelligent photovoltaic power plant connected to an electrical grid with storage to supply the laying hen rearing centers. This study requires a very competent design methodology in order to optimize the production and consumption of electrical energy. Our contribution consists in proposing a robust dimensioning synthesis elaborated according to a data flow chart. To achieve this objective, the photovoltaic system was first designed using a deterministic method, then the software "Homer" was used to check the feasibility of the design. Then, controllers (fuzzy logic) were used to optimize the energy produced and consumed. The power produced by the photovoltaic generator (GPV) is optimized by two fuzzy controllers: one to extract the maximum energy and another to control the batteries. The energy consumed by the load is optimized by a fuzzy controller that regulates the internal climate of the livestock buildings. The proposed control strategies are developed and implemented using MATLAB/Simulink.
1. The document provides an introduction to wind energy in India and Madhya Pradesh, including the history and components of wind turbines.
2. It discusses the power sector reforms that began in Madhya Pradesh in the 1990s due to financial crises, which included separating generation, transmission, and distribution functions and encouraging private sector participation.
3. The key components of a horizontal axis wind turbine are described as the rotor, blades, nacelle, low and high speed shafts, gearbox, brake, generator, anemometer, and tower.
Introducing LQR-fuzzy for a dynamic multi area LFC-DR modelIJECEIAES
It is well known that Load Frequency Control (LFC) model plays a vital role in electric power system design and operation. In the literature, much research works has stated on the advantages and realization of DR (Demand Response), which has proved to be an important part of the future smart grid. In an interconnected power system, if a load demand changes randomly, both frequency and tie line power varies. LFC-DR model is tuned by standard controllers like PI, PD, PID controllers, as they have constant gains. Hence, they are incapable of acquiring desirable dynamic performance for an extensive variety of operating conditions and various load changes. This paper presents the idea of introducing a DR control loop in the traditional Multi area LFC model (called LFC -DR) using LQR- Fuzzy Logic Control. The effect of DR-CDL i.e. (Demand Response Communication Delay Latency) in the design is also considered and is linearized using Padé approximation. Simulation results shows that the addition of DR control loop with proposed controller guarantees stability of the overall closed-loop LFC-DR system which effectively improves the system dynamic performance and is superior over a classical controller at different operating scenarios.
Centralized voltage control in medium voltage distribution networks with dist...davidtrebolle
The growing shares of distributed generation represent new challenges to distribution grids operation regarding estimation and control of voltage profile along medium and low voltage feeders. This fact leads distribution networks to become active distribution systems in order to increase monitoring and control in medium and low voltage networks. In addition, Distributed Generation (DG) may be a new resource to provide a voltage control ancillary service to Distribution System Operators (DSOs). This issue is one of the main objectives of PRICE-GDI project. This paper presents analyses carried out within this project in order to determine the benefits of voltage control provided by DG.
The new regulatory framework which is being stated in
European Network Codes includes some requirements
for DSOs regarding voltage control. This paper analyses the impact of these requirements on voltage control provided by DG
The need for enhanced power system modelling techniques and simulation toolsPower System Operation
The transition to a clean energy future requires
thorough understanding of increasingly complex
interactions between conventional generation, network
equipment, variable renewable generation technologies
(centralised and distributed), and demand response.
Secure and reliable operation under such complex
interactions requires the use of more advanced power
system modelling and simulation tools and techniques.
Conventional tools and techniques are reaching their
limits to support such paradigm shifts.
The paper highlights the need for an Active System Management (ASM) of distribution networks as a key tool for the efficient and secure integration of a high share of Distributed Energy Resources (DER). The paper provides technical and regulatory recommendations that mainly focus on distributed generation but are also largely applicable to flexible loads, electric vehicles and storage.
A NOVEL CONTROL STRATEGY FOR POWER QUALITY IMPROVEMENT USING ANN TECHNIQUE FO...IJERD Editor
The proposed system presents power-control strategies of a Micro grid-connected hybrid generation
system with versatile power transfer. This hybrid system allows maximum utilization of freely available
renewable energy sources like wind and photovoltaic energies. For this, an adaptive MPPT algorithm along with
standard perturbs and observes method will be used for the system.
The inverter converts the DC output from non-conventional energy into useful AC power for the
connected load. This hybrid system operates under normal conditions which include normal room temperature
in the case of solar energy and normal wind speed at plain area in the case of wind energy. However, designing
an optimal micro grid is not an easy task, due to the fact that primary energy carriers are changeable and
uncontrollable, as is the demand. Traditional design and optimization tools, developed for controlled power
sources, cannot be employed here. Simulation methods seem to be the best solution.
The dynamic model of the proposed system is first elaborated in the stationary reference frame and
then transformed into the synchronous orthogonal reference frame. The transformed variables are used in
control of the voltage source converter as the heart of the interfacing system between DG resources and utility
grid. By setting an appropriate compensation current references from the sensed load currents in control circuit
loop of DG, the active, reactive, and harmonic load current components will be compensated with fast dynamic
response, thereby achieving sinusoidal grid currents in phase with load voltages, while required power of the
load is more than the maximum injected power of the DG to the grid. In addition, the proposed control method
of this paper does not need a phase-locked loop in control circuit and has fast dynamic response in providing
active and reactive power components of the grid-connected loads.
Power system planning & operation [eceg 4410]Sifan Welisa
The document discusses power load forecasting and substation planning. It explains that accurate load forecasting is important for power system planning and operation. Several load forecasting methods are described, including those based on historical load data, economic factors, and standardized load curves. Load forecasts can be short, medium, or long-term. The document also discusses factors to consider in substation planning and design, such as location, equipment requirements, and configuration. Feasibility studies are important for assessing potential hydroelectric and substation projects.
Power System Reliability Assessment in a Complex Restructured Power SystemIJECEIAES
The basic purpose of an electric power system is to supply its consumers with electric energy as parsimoniously as possible and with a sensible degree of continuity and quality. It is expected that the solicitation of power system reliability assessment in bulk power systems will continue to increase in the future especially in the newly deregulated power diligence. This paper presents the research conducted on the three areas of incorporating multi-state generating unit models, evaluating system performance indices and identifying transmission paucities in complex system adequacy assessment. The incentives for electricity market participants to endow in new generation and transmission facilities are highly influenced by the market risk in a complex restructured environment. This paper also presents a procedure to identify transmission deficiencies and remedial modification in the composite generation and transmission system and focused on the application of probabilistic techniques in composite system adequacy assessment
This research presents a method for reliability assessment considering the 23MVA, 230/15 kV
transformer through two 15 kV outgoing transmission lines at Debre Markos substation. It also goes further to
include 139 low voltage 15/0.4 kV distribution transformers. The total load connected to the 15 kV feeders are
varies between 0.33255 and 6.3185 MW. A composite system adequacy and security assessment is done using
Monte Carlo simulation. The basic data and the topology used in the analysis are based on the Institution of
Electrical and Electronics Engineers - Reliability Test System and distribution system for bus two of the IEEEReliability
Bus bar Test System. The reliability indices SAIDI, SAIFI, CAIDI, EENS, AENS, ASAI, ASUI, and
expected interruption costs are being assessed and considered. Distribution system reliability information was
obtained from actual data for systems operating in Ethiopia Electric Utility office and Debre Markos substation
recorded data and online SCADA system.
1) A distributed energy future will require distribution utilities to plan, operate, and innovate in new ways to integrate distributed energy resources and accommodate two-way power flows on the grid.
2) This changing paradigm encompasses seven dimensions including two-way power flows, local integration and balancing of resources, functional control of distributed resources, and new business models.
3) Distribution utilities will need to develop new planning approaches to handle issues like two-way power flows, energy storage and electric vehicles, demand response, and renewable energy forecasting. They will also need to collect and analyze more data from smart grids and distributed sensors.
Loss Reduction by Optimal Placement of Distributed Generation on a Radial feederIDES Editor
Due to the increasing interest on renewable sources
in recent times, the studies on integration of distributed
generation to the power grid have rapidly increased. In order
to minimize line losses of power systems, it is crucially
important to define the location of local generation to be placed.
Proper location of DGs in power systems is important for
obtaining their maximum potential benefits. This paper
presents analytical approaches to determine the optimal
location to place a DG on radial systems to minimize the power
loss of the system. Simulation results are given to verify the
proposed analytical approaches.
A Review on Optimization Techniques for Power Quality Improvement using DSTAT...ijtsrd
This document summarizes a research paper that proposes using a neural network approach to optimize techniques for improving power quality using a DSTATCOM (Distribution Static Compensator). It begins by introducing common power quality issues like voltage sags, swells, and harmonics. It then discusses different custom power devices used to address these issues, focusing on the DSTATCOM. The paper proposes a control algorithm using a backpropagation neural network to extract reference currents and control the DSTATCOM for reactive power compensation, load balancing, and voltage regulation. Simulation results showed the DSTATCOM was able to satisfactorily compensate for different types of loads using this neural network approach.
This document introduces the concepts of Distributed Flexible AC Transmission Systems (D-FACTS) as an alternative approach to realizing cost-effective power flow control. Specifically:
1) It proposes distributed series impedance (DSI) and distributed static series compensator (DSSC) devices that can be clamped onto existing power lines to dynamically and statically control power flow.
2) DSI and DSSC work by varying the impedance of power lines using small modules containing reactive elements and single turn transformers, without requiring a break in the transmission line.
3) This distributed approach could provide higher performance and lower cost active power flow control compared to conventional FACTS devices, through scalability,
Single core configurations of saturated core fault current limiter performanc...IJECEIAES
Economic growth with industrialization and urbanization lead to an extensive increase in power demand. It forced the utilities to add power generating facilities to cause the necessary demand-generation balance. The bulk power generating stations, mostly interconnected, with the penetration of distributed generation result in an enormous rise in the fault level of power networks. It necessitates for electrical utilities to control the fault current so that the existing switchgear can continue its services without upgradation or replacement for reliable supply. The deployment of fault current limiter (FCL) at the distribution and transmission networks has been under investigation as a potential solution to the problem. A saturated core fault current limiter (SCFCL) technology is a smart, scalable, efficient, reliable, and commercially viable option to manage fault levels in existing and future MV/HV supply systems. This paper presents the comparative performance analysis of two single-core SCFCL topologies impressed with different core saturations. It has demonstrated that the single AC winding configuration needs more bias power for affecting the same current limiting performance with an acceptable steady-state voltage drop contribution. The fault state impedance has a transient nature, and the optimum bias selection is a critical design parameter in realizing the SCFCL applications.
Economic Impacts of Behind the Meter Distributed Energy Resources on Transmis...Power System Operation
The increasing penetration of customer-owned Distribution Energy Resources (DERs) will have an impact on the economics that govern market operation. Visibility and control of local Independent System Operators (ISOs) over these resources are currently restricted or available in some form of aggregation. Additionally, non-curtailable resources pose a serious problem while balancing the market with eminent risks of over-generation and added congestion to the system. This study attempts to decouple the model at the Transmission-Distribution interface and demonstrate the following: 1) economic implications of such resources under two control strategies, 2) aspects of market dynamics affected by several DER penetration levels, 3) Potential benefits of increased ISO visibility beyond the Transmission-Distribution(T-D) interface.
This document summarizes a study on distributed energy resources (DER). It discusses how increased DER is changing power systems and potential reliability issues. DER provides alternatives to large central plants but can impact transmission systems. The document recommends:
1) Collecting and sharing DER location, type, and performance data across transmission and distribution systems to support modeling.
2) Modeling DER in bulk power system studies if significant impacts are expected based on location and output.
3) Avoiding netting of DER with load and instead aggregating or explicitly modeling DER based on penetration levels.
Impact of dynamic demand response in the load frequency controlIRJET Journal
This document discusses the impact of dynamic demand response (DR) in load frequency control (LFC). It presents a model called LFC-DR that introduces a DR control loop to the traditional LFC model for a single-area power system. The model allows for optimal power sharing between DR and supplementary control. Simulation studies are carried out to verify the model and show that the addition of the DR control loop increases stability and improves dynamic performance by effectively utilizing DR. The LFC-DR model provides a general framework for analyzing the effects of DR on power system dynamics and controller design.
A Survey on Impact Assessment of D-FACTS Controllers with Electric Vehicles i...IRJET Journal
This document summarizes a research paper that assesses the impact of electric vehicles (EVs) and distribution static synchronous compensator (D-STATCOM) controllers on electric distribution networks. It finds that EVs can negatively impact power quality through increased voltage drops and imbalance factors. The document also reviews past literature on distributing distributed generation and flexible AC transmission system devices like D-STATCOM in distribution systems. It identifies gaps in assessing unbalanced and mixed distribution systems with these technologies and calls for more probabilistic studies of their combined impacts with variable loads.
Contingency plans based on N - 1 and N - 2 contingencies are already very much used by utilities . Artificial intelligent methods are new trends for analysing the contingency scenario along with state of art congestion management. This gives extra backup and b oost to reliable operation under contingent scenario of power system. This paper envisages the summary of all those efforts. This paper will help utilities to put more thinking in terms of recent developments in fast and intelligent computing methods. The paper highlights classical research and modern trends in contingency analysis such as hybrid artificial intelligent methods. Steady state stability assessment of a power system pursues a twofold objective:first to appraise the system's capability to withs tand major contingencies,and second to suggest remedial actions,i.e. means to enhance this capability,whenever needed. The first objective is the concern of analysis,the second is a matter of control.
Optimal Siting And Sizing Of Distributed Generation For Radial Distribution S...inventy
Research Inventy provides an outlet for research findings and reviews in areas of Engineering, Computer Science found to be relevant for national and international development, Research Inventy is an open access, peer reviewed international journal with a primary objective to provide research and applications related to Engineering. In its publications, to stimulate new research ideas and foster practical application from the research findings. The journal publishes original research of such high quality as to attract contributions from the relevant local and international communities.
Power-Sharing of Parallel Inverters in Micro-Grids via Droop control and Virt...IRJET Journal
This document discusses two power-sharing control strategies - droop control and virtual impedance - for parallel inverters in microgrids. Droop control simulates the frequency-power characteristics of conventional power systems but has limitations like load-dependent voltage regulation. Virtual impedance modifies the output impedance of inverters to improve current sharing. The document analyzes these approaches and compares their performance in sharing power between parallel inverters through MATLAB simulations under different weather conditions. It finds that both techniques effectively share load power while improving system stability and response, with virtual impedance providing better voltage regulation.
Automatic generation control problem in interconnected power systemsAlexander Decker
This document discusses automatic generation control (AGC) in interconnected power systems. It begins by describing the structure of modern power systems and identifying AGC as an important control problem. It then provides details on the duties of AGC, including maintaining frequency and regulating power flows between interconnected areas. The document describes different types of frequency deviations and the associated primary, secondary, and emergency control responses needed to maintain reliable system operation. It also outlines the hierarchical timescales of different control functions, from governor response to economic dispatch. Diagrams are included to illustrate typical AGC control loops and the dynamic response to a generation trip event.
Congestion Management in Deregulated Power System by Using FACTS DevicesIRJET Journal
This document discusses congestion management in deregulated power systems using Flexible AC Transmission System (FACTS) devices. It begins with an introduction to the problem of transmission line overloading and congestion in deregulated power markets. It then discusses how FACTS devices like Thyristor Controlled Series Capacitor (TCSC) can be used to reduce flows in heavily loaded lines and manage congestion. The document presents a case study using the IEEE 14-bus test system and PowerWorld Simulator software to analyze the impact of installing a TCSC on congested lines. It shows that the TCSC is effective at overcoming congestion by changing power flows and making locational marginal prices uniform across the system.
Modeling Approaches and Studies of the Impact of Distributed Energy Resources...Power System Operation
New modelling approaches and studies are needed to address the challenges from the deepening penetration of distributed energy resources (DER) on distribution networks insofar as they impact the reliability of the bulk electric system (BES) [1]. Operational challenges on the distribution system can manifest in forms of overvoltage, reverse power flows, difficulties in protection co-ordination etc. Adverse impacts on the BES can be as severe as cascading outages resulting from the simultaneous tripping of large amounts of DER and delayed system recovery due to a lack of voltage and frequency support from DER.
Modeling Approaches and Studies of the Impact of Distributed Energy Resources...Power System Operation
New modelling approaches and studies are needed to address the challenges from the deepening penetration of distributed energy resources (DER) on distribution networks insofar as they impact the reliability of the bulk electric system (BES) [1]. Operational challenges on the distribution system can manifest in forms of overvoltage, reverse power flows, difficulties in protection co-ordination etc. Adverse impacts on the BES can be as severe as cascading outages resulting from the simultaneous tripping of large amounts of DER and delayed system recovery due to a lack of voltage and frequency support from DER.
To meet these challenges two distribution system modelling approaches to study the impact of DER on the BES reliability are presented in this paper – an aggregated modelling approach [2] and a full modelling approach. The aggregated distribution system model comprises an equivalent/aggregate distribution system model (including an aggregate load model and an equivalent feeder segment) and an aggregate dynamic DER model. The aggregated distribution system model is connected to a transmission system model to enable studying the impact of DER on the BES. In the full distribution system modelling approach, on the other hand, the non-aggregated distribution system and individual DER are modelled. Connecting the full distribution system model to a transmission system model on the same simulation platform offers another approach to study the impact of DER on the BES. The transmission and the full distribution system modelling as a whole is referred to as the T&D combined model. The performance of both distribution system modelling approaches is compared and contrasted in BES stability studies. While the aggregated modelling approach provides a simplistic
Optimal dg placement using multiobjective index and its effect on stability 2IAEME Publication
This document summarizes an article from the International Journal of Electrical Engineering and Technology. The article discusses optimal placement of distributed generation (DG) in distribution systems using a multi-objective performance index. It studies DG placement on IEEE test feeders and a practical distribution system in India. It analyzes the impact of DG placement on transient stability, voltage, frequency and rotor angle during faults. It also examines coordination of overcurrent protection relays with and without DG, using directional and non-directional relays. The study aims to minimize power losses, improve voltage profiles and ensure reliable protection with high DG penetration.
IRJET-Identification of Weak Bus using Load VariationIRJET Journal
This document discusses identifying weak buses in a power system through load variation analysis. It uses the WSCC 3-Machine 9-Bus test system in PSAT, a MATLAB toolbox, to analyze the system under increasing load levels from 5% to 45%. By comparing the results to the original power flow, the aim is to determine the most sensitive bus that is most affected by load changes. It explains that identifying weak buses can help with optimal reactive power planning by determining where new reactive power sources are most needed to prevent voltage instability and collapse.
IRJET- Optimization of Renewable Energy Sources for DC MicrogridIRJET Journal
The document discusses optimization of renewable energy sources for DC microgrids. It proposes integrating wind and solar energy generation with battery storage in a microgrid connected to buildings. This hybrid system improves reliability by reducing storage needs when the generation sources have opposing output cycles. The document models and simulates such a system, showing the wind and solar outputs, storage controller, and grid connection. Integrating distributed renewable sources with storage in microgrids helps stabilize grids with intermittent generation and maximize use of transmission infrastructure.
Stochastic control for optimal power flow in islanded microgridIJECEIAES
The problem of optimal power flow (OPF) in an islanded mircrogrid (MG) for hybrid power system is described. Clearly, it deals with a formulation of an analytical control model for OPF. The MG consists of wind turbine generator, photovoltaic generator, and diesel engine generator (DEG), and is in stochastic environment such as load change, wind power fluctuation, and sun irradiation power disturbance. In fact, the DEG fails and is repaired at random times so that the MG can significantly influence the power flow, and the power flow control faces the main difficulty that how to maintain the balance of power flow? The solution is that a DEG needs to be scheduled. The objective of the control problem is to find the DEG output power by minimizing the total cost of energy. Adopting the Rishel’s famework and using the Bellman principle, the optimality conditions obtained satisfy the Hamilton-Jacobi-Bellman equation. Finally, numerical examples and sensitivity analyses are included to illustrate the importance and effectiveness of the proposed model.
System operators face a proliferation of power electronics
interfaced devices such as HVDC transmission lines,
wind and solar generation in their grids. Depending on
the jurisdiction, the instantaneous share of electrical
energy produced from renewable energy sources
occasionally reaches 150%. However, to operate a power
system with sustained high levels of renewable energy,
several operational challenges need to be addressed. The
goal of this survey paper, which is one of the products
of CIGRE joint working group C2/B4.38, is to identify
such challenges. To this extend, extensive literature
review and survey among and discussions with system
operators throughout the world were performed.
This paper identified several operational challenges that
were validated by system operators. These challenges
are grouped in the following three categories: (i) new
behavior of the power system, (ii) new operation of the
power system and (iii) lack of voltage and frequency
support. For each of the identified challenge, a
description, practical examples and relevant references
are provided.
This document summarizes an article that proposes an automatic demand response controller with a load shifting algorithm implemented using MATLAB software. The controller monitors generation capacity and customer demand to optimally schedule loads to reduce peak demand and stabilize the load curve. A mathematical model is presented that shifts loads in priority order from the lowest to highest load if total demand exceeds generation capacity. The model was tested on an 8 bus system in MATLAB and successfully stabilized the load curve to better manage power demand according to supply conditions.
IRJET- A Review on Hybrid AC/DC Microgrid System and its Coordination Con...IRJET Journal
This document summarizes a research paper on hybrid AC/DC microgrid systems and their coordination control. It begins with an abstract that outlines the benefits of hybrid AC/DC microgrids in integrating renewable energy sources while avoiding multiple power conversions. It then reviews several previous studies on hybrid microgrid control strategies and topologies. Key challenges discussed include maintaining stable operation during different generation and load conditions. The document concludes that hybrid AC/DC microgrids can minimize conversion losses but require further research on coordination control and other technical issues to enable practical implementation.
This document discusses electrical energy management and load forecasting in smart grids using artificial neural networks. It presents a study applying backpropagation neural networks to short-term load forecasting for Sudan's National Electric Company. The neural network model was used to forecast load, with error calculated by comparing forecasted and actual load data. The document also discusses generation dispatch, demand forecasting techniques, and designing a neural network for one-day load forecasting. It evaluates network performance and error for different training data sizes, finding that a ten-day training dataset produced the best results with minimum error. The neural network approach was able to reliably predict the nonlinear relationship between historical data and load.
Similar to Reliability Impacts of Behind the Meter Distributed Energy Resources on Transmission Operations (20)
The document provides highlights and key insights from the DNV Energy Transition Outlook 2021 report. It finds that:
1) Global emissions are not decreasing fast enough to meet Paris Agreement goals, and warming is projected to reach 2.3°C by 2100 despite renewable growth.
2) Electrification is surging, with renewables like solar and wind outcompeting other sources by 2030 and providing over 80% of power by 2050, supported by technologies like storage.
3) Energy efficiency gains lead to flat global energy demand after the 2030s, with a 2.4% annual improvement in energy intensity outpacing economic growth.
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SVC PLUS Frequency Stabilizer Frequency and voltage support for dynamic grid...Power System Operation
SVC PLUS
Frequency Stabilizer
Frequency and voltage support for dynamic grid stability
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Balancing services help maintain the frequency of the power grid by providing short-term energy or capacity reserves. They include balancing energy, which system operators use to maintain grid frequency, and balancing capacity, which providers agree to keep available. Different balancing services have varying activation speeds to respond to frequency deviations. Harmonization efforts in Europe are working to establish common balancing markets and platforms for cross-border exchange of reserves.
The Need for Enhanced Power System Modelling Techniques & Simulation Tools Power System Operation
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Power Quality Trends in the Transition to Carbon-Free Electrical Energy SystemPower System Operation
Power Quality
Trends in the Transition to
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A Power Purchase Agreement (PPA) is a long-term contract between an electricity generator and purchaser that defines the conditions for the sale of electricity. PPAs provide price stability and help finance renewable energy projects by guaranteeing revenue. There are physical PPAs, which deliver electricity directly, and virtual PPAs, which financially settle the contract without physical delivery. PPAs benefit both renewable developers by enabling project financing, and buyers seeking long-term electricity price certainty and renewable attributes.
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Electric vehicle and photovoltaic advanced roles in enhancing the financial p...IJECEIAES
Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
Comparative analysis between traditional aquaponics and reconstructed aquapon...bijceesjournal
The aquaponic system of planting is a method that does not require soil usage. It is a method that only needs water, fish, lava rocks (a substitute for soil), and plants. Aquaponic systems are sustainable and environmentally friendly. Its use not only helps to plant in small spaces but also helps reduce artificial chemical use and minimizes excess water use, as aquaponics consumes 90% less water than soil-based gardening. The study applied a descriptive and experimental design to assess and compare conventional and reconstructed aquaponic methods for reproducing tomatoes. The researchers created an observation checklist to determine the significant factors of the study. The study aims to determine the significant difference between traditional aquaponics and reconstructed aquaponics systems propagating tomatoes in terms of height, weight, girth, and number of fruits. The reconstructed aquaponics system’s higher growth yield results in a much more nourished crop than the traditional aquaponics system. It is superior in its number of fruits, height, weight, and girth measurement. Moreover, the reconstructed aquaponics system is proven to eliminate all the hindrances present in the traditional aquaponics system, which are overcrowding of fish, algae growth, pest problems, contaminated water, and dead fish.
CHINA’S GEO-ECONOMIC OUTREACH IN CENTRAL ASIAN COUNTRIES AND FUTURE PROSPECTjpsjournal1
The rivalry between prominent international actors for dominance over Central Asia's hydrocarbon
reserves and the ancient silk trade route, along with China's diplomatic endeavours in the area, has been
referred to as the "New Great Game." This research centres on the power struggle, considering
geopolitical, geostrategic, and geoeconomic variables. Topics including trade, political hegemony, oil
politics, and conventional and nontraditional security are all explored and explained by the researcher.
Using Mackinder's Heartland, Spykman Rimland, and Hegemonic Stability theories, examines China's role
in Central Asia. This study adheres to the empirical epistemological method and has taken care of
objectivity. This study analyze primary and secondary research documents critically to elaborate role of
china’s geo economic outreach in central Asian countries and its future prospect. China is thriving in trade,
pipeline politics, and winning states, according to this study, thanks to important instruments like the
Shanghai Cooperation Organisation and the Belt and Road Economic Initiative. According to this study,
China is seeing significant success in commerce, pipeline politics, and gaining influence on other
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### Applications of TDM
- **Telecommunications**: TDM is extensively used in telecommunication systems, such as in T1 and E1 lines, where multiple telephone calls are transmitted over a single line by assigning each call to a specific time slot.
- **Digital Audio and Video Broadcasting**: TDM is used in broadcasting systems to transmit multiple audio or video streams over a single channel, ensuring efficient use of bandwidth.
- **Computer Networks**: TDM is used in network protocols and systems to manage the transmission of data from multiple sources over a single network medium.
### Advantages of TDM
- **Efficient Use of Bandwidth**: TDM all
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Reliability Impacts of Behind the Meter Distributed Energy Resources on Transmission Operations
1. ranilkumar@quanta-technology.com
21, rue d’Artois, F-75008 PARIS CIGRE US National Committee
http://www.cigre.org 2019 Grid of the Future Symposium
Reliability Impacts of Behind the Meter Distributed Energy Resources on
Transmission Operations
R. ANILKUMAR, A. DANESHPOOY, V. MARATHE
Quanta Technology LLC
USA
SUMMARY
The increasing amounts of customer-owned Distributed Energy Resources (DERs) limit the
control and visibility of local Independent System Operators (ISOs) and utility operators.
Most of these resources are non-curtailable and subject to several aggregation guidelines for
wholesale participation. These units cannot be decoupled from the Transmission-Distribution
(T-D) interface and have a direct impact on the economics and reliability of the grid. This
paper reports the results of a study that investigated realistic dispatch conditions from a
production and power flow co-simulation environment with increased behind-the-meter DER
resources. The objectives of this study include: 1) understanding steady-state and transient
voltage response of the system at the local T-D interface, 2) analyzing impacts on switching
operations, 3) studying the system-wide frequency response of the Western Interconnection,
and 4) examining scenarios that provide insight into the type of control strategies that best
benefit local ISO and utility operations from a reliability perspective.
KEYWORDS
Distributed energy resources, frequency response, production simulation, power flow
simulations, curtailments.
2. 2
1. INTRODUCTION
The recent advancements in technology and policies have driven the growth of Distributed Energy
Resource (DER) into the grid. Several states, including California and New York, have established
Renewable Portfolio Standards (RPSs), which would require close to 50% of their energy procurement
to come directly from renewable resources by the year 2030. Over time, these targets have become
more aggressive, resulting in 100% by the year 2045 [1].
Several potential impacts have been identified by industry and academic researchers that demonstrate
the economic and operational impacts of these resources. The key challenges associated with DERs are
directly attributed to their operating characteristics. This is coupled with state and federal policies
driving the retirement of coal and nuclear plants [2]. The existing fleet of generation would likely need
to operate at lower minimum levels if not already uncommitted. For example, there is an increased
likelihood of over-generation resulting in reverse power flows at the Transmission-Distribution (T-D)
interface, resulting in protection equipment failures. The displacement of large-scale units can severely
impact the system-wide frequency response and NERC BAL-003 requirements [3]. The off-peak hours
(particularly, high ramping) can result in voltage issues that arise from the offset of generation and load
balance. Similarly, there can be scenarios of excessive shunt-capacitor and transformer-tap switching
necessary to maintain scheduled voltages at the T-D interfaces [4]. The focus of this paper is on the
operational reliability impacts of these resources directly associated with local and system-wide
reliability.
DERs are currently divided into three categories, customer-owned/Behind-the-Meter DER (BTM-
DER), Merchant DER, and microgrids. Among the three, most Independent System Operators (ISOs)
have control over their merchant DERs, which are typically larger units that can be curtailed as per the
ISO request. However, BTM units are not within the full visibility of ISO operations. Without visibility
to these resources, ISO’s cannot include them in the state RPS targets as firm procurements, even
though they can impact the transmission grid more indirectly through the T-D interface.
Currently, these BTM-DERs are modified as a load modifier. BTM and Net Energy Metering (NEM)
mask the generation within the available load schedule. However, for accurate modeling, it is
imperative to distinguish load from generation and establish differentiated load and generation data.
This level of accuracy should be included within the market assessment tools and the power-flow-based
tools. In order to capture their response in power-flow studies during fault and outage conditions, it is
essential to establish dynamic models as well.
While several studies have been performed highlighting the impacts of DER penetration into the grid
[4–11], no study has analyzed the operational visibility considerations as they impact market and
reliability aspects of the power system directly at the T-D interface. The thin line between controllable
and non-controllable resources can have several implications on system operations. The objective of
this study is to highlight some of the key aspects of DER penetration into the grid using the state of
California as an example. The study will account for the larger merchant DER (controllable) and
BTM-DER (non-controllable) to better capture all aspects of DER operations. A coupled market and
power-flow simulation has been used to study this in detail; however, the focus of this paper will
remain on the power-flow implications of the problem.
2. MODELING, ASSUMPTIONS AND STUDY METHODOLOGY
2.1. Scenario Description
To study reliability impacts at the T-D interface, two scenarios are considered. The non-participating
scenario, herein referred to as Scenario 1, represents current market operations where distribution-
connected renewables deliver only active power. These units are non-curtailable, do not provide
reactive power support or any form of frequency support, nor are they equipped with intelligent
protection or ride-through settings.
The participating scenario, herein referred to as Scenario 2, considers a model where BTM units can
contribute to reactive power support and frequency regulation within the rated capabilities. The model
further includes ride-through settings and additional protection configurations for these units. These
3. 3
models also include latch/trip ranges for frequency and voltage response. Further, they represent a
future market model evolution to be considered, where the ISO has control over the distribution-
connected resources as well, either in the form of generation resources(energy) or ancillary services.
2.2. Modeling, Assumptions, and Study Methodology
Production simulations were performed using ABB’s GridView software tool. The 2024 Transmission
Expansion Planning Policy Committee (TEPPC) base cases were used, which included the most
current statewide RPS requirements within the Western Electricity Coordinating Council (WECC).
The objective was to mimic market operations and identify the worst-operating days and hours for the
local ISO. These days were evaluated in further detail using power-flow and dynamic-transient
simulations.
The DER penetration levels considered in this study are based on the published California Energy
Commission (CEC) forecasts for self-generation in the year 2024 [12]. Detailed models were built, and
the DER forecast was implemented at distribution and sub-transmission networks. Equivalent
impedances were calculated to represent the distribution network model within commercially available
transmission planning and market operational tools like GE Positive Sequence Load Flow (PSLF) [13]
and ABB GridView [14]. With the models that were built for Scenario 1 and Scenario 2 conditions,
studies were conducted at 100 and 200% CEC renewable penetration levels.
Within the production simulation, a detailed representation of the BTM-DER generation was modeled.
The representation is highlighted by Fig. 1 below. To enable market participation, they were modeled
as aggregations for each local utility within the state and assigned participation factors. A similar
model was built out in the power-flow cases as well.
• The BTM- DER was modeled at several buses ranging from 4.7 kV to 230 kV and includes
PV(residential) and non-PV (commercial generation) units. Based on the CEC forecast, the total
generation added was 4,000 MW, which includes 2,100 MW of PV and 1,900 MW of non-PV
generation for the 100% penetration scenario. For the 200% penetration scenario, the total
generation added was 8,000 MW, which includes 6,100 MW of PV and 1,900 MW of non-PV
generation. Under the assumption that load is being offset by a proportional increase in
self-generation, a total of 4,000 MW of load was added at the locations (similar to the additional
self-generation units added). For accuracy, loads and generations were modeled separately. The
same load was assumed for both 100 and 200% scenarios.
Fig. 1. BTM-Distributed Generation (DG) model for power flow and production simulation.
• PV and non-PV generation was interconnected at appropriate voltage levels through equivalent
impedances and the DG interconnection transformer. The equivalent impedances represent the
aggregate value of distribution and/or sub-transmission lines, as well as substation transformer
impedances, as obtained from the short-circuit capacity of the system.
4. 4
• Generation and load dispatches from production simulation were imported into multiple power-
flow cases to analyze the 100 and 200% penetration levels. In this paper, spring off-peak conditions
for 11 AM and 8 PM are considered. Operationally, these were identified as the most critical hours
of the day.
• For dynamic simulations, “PVD1” model were used for the BTM generation. In Scenario 1, active
power control is a priority and no reactive power support capability is associated with these units;
in Scenario 2 simulations, the PF flag is set to 0, wherein reactive power control is a priority and
reactive power support is provided by these units. Further, Scenario 1 did not include low/high
voltage ride-through and frequency ride-through protection considerations. All loads were replaced
with the WECC composite load model.
• The CEC generation non-PV units represent typical synchronous machine for combined heat and
power (CHP) units. In the dynamic model the unit is represented by a GENROU model with an
Exciter (EXST1), governor (GGOV1) and power system stabilizer (PSS1D). All protection
considerations are applied to these units.
3. POWER FLOW STUDY
The local-area power flow study was conducted to analyze the impact of DER penetration on voltages.
The larger penetration of DER can result in overvoltages, larger transformer tap swings, lower
voltages during off-peak conditions with larger imbalance (generation vs load), while making the
system more sensitive to critical contingencies.
3.1. Steady State Assessment
The region-wide voltage study was used to assess the impact of contingencies on voltages at all buses
in the ISO region of 100 kV and above. The steady-state assessment was performed in adherence to
WECC and regional ISO planning standards [15]. PSLF simulation environment was used for this
study.
Results from the 100 and 200% penetration studies were analyzed for both Scenarios 1 and 2. Two
different hours of the day were considered (11 AM and 8 PM). Several comparisons were drawn
between these operating conditions that provide insight into the operation of the system:
1. Excessive capacitor-bank switching was observed in Scenario 1, without voltage control from
local DER. Further, there were a total of 125 tap-changing operations recorded while moving from
11 AM to 8 PM on the same day (2.48% of tap-up and 6.875% of tap-down operation).
2. In Scenario 1 under 200% CEC penetration, there were reduced tap-down operations between
11 AM to 8 PM of the operating day but an increased percentage of tap-up operations. Several
capacitor banks were at peak capacity by 8 PM in this operating scenario.
3. In Scenario 1, under 100 and 200% penetration, several undervoltages were observed in the
system, with the lowest being 0.92 pu. Additional support from compensation devices is critical to
prevent voltage from being significantly suppressed.
4. In Scenario 2, under 100 and 200% penetration, reduced undervoltages were observed in the
system. Between the two cases, the lowest voltage recorded was 0.94 p.u..
5. Post-contingency responses were observed between both scenarios, and no delta V deviations of
greater than 8% were recorded. Several high voltages were recorded throughout the system, with
the highest being 1.11 p.u. at the 115-kV network.
6. Interestingly in both scenarios, while moving from 11 AM to 8 PM, larger tap-down operations
were recorded in the 100% scenario than in the 200% scenario. The 200% scenario reported
reduced transformer tap-change operations overall.
7. Table 1 presents a high-level overview of the highest and lowest voltages recorded for both
scenarios at a sample substation in the PG&E operating area. The results at the T-D interface
demonstrate that larger deviations are observable under Scenario 1 and at 8 PM. The results
5. 5
indicated that the 230-kV T-D interface interconnections are less impacted by voltage deviations
than the 115-kV network.
Table 1: Pre and post contingency voltage deviations at T-D interfaces
Pre- and Post-Voltage
Deviations @
San Ramon 230 kV
substation
200% - Scenario 1 200% - Scenario 2
11 AM 8 PM Δ V 11 AM 8 PM Δ V
Pre-
Cont.
Base
Case
1.021 1.012 0.01 1.015 1.012 0.003
Post-
Cont.
C2_8 1.008 0.989 0.019 0.993 0.993 0
Δ V 0.013 0.023 0.022 0.019
Post-
Cont.
C2-11 1.015 0.99 0.025 0.993 0.993 0
Δ V 0.006 0.022 0.022 0.019
Pre and Post Voltage
Deviations@ 115 kV
substation
100% - Scenario 1 100% - Scenario 2
11 AM 8 PM Δ V 11 AM 8 PM Δ V
Pre-
Cont.
Base
Case
1.053 1.033 0.01 1.04 1.029 0.011
Post-
Cont.
SL-
10117
1.038 1.018 0.02 1.026 1.024 0.002
Δ V 0.015 0.015 0.014 0.005
Post-
Cont.
SL-
10235
1.041 1.021 0.02 1.028 1.027 0.001
Δ V 0.012 0.012 0.012 0.002
4. TRANSIENT DYNAMIC SIMULATIONS
To perform dynamic simulations, a three-phase-to-ground bolted fault was applied at the remote bus,
followed by an immediate line loss connecting the remote bus to the T-D interface. The logic behind
using a remote bus was to examine the behavior of PV units in scenarios where their tripping is not
always certain. Further, if a three-phase fault was applied at the T-D interface directly, there is
certainty that the PV unit will trip, not providing much ground to explore the exact transient response
from these units. The fault was applied at 0.1 seconds in all simulations and cleared in 6 cycles.
Composite load models were evaluated in detail.
In order to evaluate the transient voltage response at the T-D interface, two substations are presented
below. For, the San Ramon 230-kV T-D interface, a fault was applied at Moraga 230-kV bus, and the
line was cleared after 6 cycles. An average reduction of 2-MW output was observed at all loads in the
composite load model for the 11 AM case, and a reduction of 1-MW output observed at all loads in the
composite load model for the 8 PM case for Scenario 1 with 200% injection. It was observed that the
bus voltage settles down at the nominal value after the fault is cleared and no PV-unit trip was
recorded. The behavior of the composite load for 200% penetration at San Ramon is presented in
Fig. 2.
The voltage overshoot post-fault clearing was more pronounced at 11 AM than 8 PM in both
scenarios. Interaction from neighboring PV units in the system also contribute to the post-fault
clearing voltage overshoot. This is presented in Fig. 3.
Table 2 summarizes the results obtained from the studies in Scenario 1. It includes the MW generation
tripped from the PV unit and the cause for tripping. “N/A” indicates scenarios where no PV-unit trip
was recorded.
6. 6
Fig. 2. Composite load model at San Ramon T-D interface - 200%, Scenario 1.
Fig. 3. Voltages at T-D interface, 11 AM and 8 PM.
Table 2: Select T-D interfaces and cause for PV trip in Scenarios 1 & 2
Bus
Name
Scenario
Scenario 1 Scenario 2
Generation
tripped (MW)
Load Tripped
(MW)
Generation
tripped (MW)
Load Tripped
(MW)
San
Ramon
200% -
11AM
40 8 N/A 4
Huron
200% -
11AM
20 (Frequency) 2 N/A 2
San
Ramon
100% -
11AM
N/A 13 N/A 8
Huron
100% -
11AM
35 7 10 5
In Scenario 2, the CEC generator models were equipped with reactive power capability. Low/High
voltage/frequency ride through configurations were implemented based on distribution consensus
standards. In this scenario, the number of PV units tripped was less than for Scenario 1. This can be
observed in Table 2.
The following observations can be made from the system-wide voltage study and local T-D interface
study.
• It was observed from dynamic simulations that the composite load models recorded a maximum of
10-MW reduction post-fault clearing.
• PV DG tripping recorded due to frequency and voltage swings are more significant in the sub-
transmission network.
• In Scenario 2, voltages at the T-D interface buses are supported by reactive power contribution
from PV and non-PV units. Since no low-voltage/high-voltage scenarios were encountered at the
interface bus in the base case, most of the Q variations in these units were observed in response to
fault conditions.
7. 7
The plots in Fig. 4 demonstrate the dependence of frequency on the MW output of the power-flow
model under Scenario 2. Faults near and downstream from the 115kV network reduce the plant output
significantly until the frequency recovers. Under Scenario 1, the tripping of several PV units was
observed throughout the region. Most of the trips were in response to frequency swings measured at
the bus.
Fig. 4. PV plant output and frequency at T-D interface bus (Huron)
5. SYSTEM WIDE FREQUENCY RESPONSE STUDY
Frequency response has recently gained a lot of attention across the Western Interconnection. The
purpose of this study is to investigate the frequency performance of the California region in response to
events of sudden generation loss , particularly those targeted by NERC standard BAL–003 under near-
future conditions with high levels of renewable generation. This study addresses the overall frequency
response of the Western Grid, with special attention to the response within the local California region.
Some of the major system impacts resulting from increased renewable generation include lower system
inertia and displacement of primary frequency control reserves [16].
The objective was to capture the frequency response of the entire WECC system and California
Independent System Operator (CAISO) region for the Palo Verde double outage; simulation was
performed for 60 seconds. The original production simulation results were used to create the seed case
– herein referred to as Case 1.
A more conservative scenario was developed from Case 1 using reduced headroom in the WECC and
CAISO regions – herein referred to as Case 2. The frequency performance metrics for the two cases
are tabulated in Table 3. The frequency at the Round Mountain 500-kV facility is shown in Figs. 5 and
6 for Case 1 and Case 2, respectively, under Scenario 1. For Scenario 2, with the cases in the study
having the same headroom as shown in Table 4, it was observed that the results obtained are
comparable to the results obtained in Scenario 1 and were not reproduced.
From the performance metrics, it was observed that the frequency performance within WECC for
Scenario 1 and Scenario 2 was acceptable. WECC system response slightly reduced in Scenario 2.
However, for the CAISO the response improved. This is due the marginal differences between
dispatches in Scenario 1 and Scenario 2. This response could also be attributed to a large PV unit’s
frequency self-resettling capability and wider frequency range for Scenario 2.
8. 8
Table 3: Frequency performance metrics
Case 1
Scenario 1 Scenario 2
WECC CA WECC CA
Frequency Nadir (Hz) 59.685 59.68 59.691 59.691
Frequency Nadir time (seconds) 6.94 6.79 6.88 6.8
Settling Frequency (Hz) 59.83 59.83 59.836 59.836
Frequency Response (MW/0.1Hz) 2236 269 2210 278
Case 2
Scenario 1 Scenario 2
WECC CA WECC CA
Frequency Nadir (Hz) 59.54 59.54 59.56 59.55
Frequency Nadir time (seconds) 9.22 9.12 9.18 9.1
Settling Frequency (Hz) 59.751 59.751 59.758 59.758
Frequency Response (MW/0.1Hz) 1324 168 1320 170.9
Fig. 5. Frequency at Round Mountain 500 kV facility for Case 1 Scenario 1
Fig. 6. Frequency at Round Mountain 500 kV facility for Case 2 Scenario 1
9. 9
Table 4: Headroom in study cases
Case
Headroom (GW)
WECC CAISO
Case 1 ~ 19 ~ 3.95
Case 2 ~13.7 ~2.3
6. CONCLUSIONS
This paper evaluated the impact of uncontrolled BTM resources on the T-D interface. A coupled
production/power flow simulation environment was used to capture all aspects of the problem. The
study did not identify any serious concerns at the T-D interface. The reliability of the system can be
successfully ensured with good system planning and power system engineering practices. At a
minimum, local voltage and thermal problems were identified that will require capacity expansion to
accommodate the increased penetration. Scenarios with active participation from BTM resources
demonstrated considerable improvement in system reliability. The system frequency response was
observed to deteriorate without active DER controls allocated to all participating BTM units.
Distribution is not decoupled from transmission and will continue to impact bulk power system
operations, largely from a system-wide frequency-response perspective. From a steady-state and
transient voltage perspective, the issues were largely localized in nature, with the strength of the grid
at the point of interconnection and switching action of compensating devices influencing voltage
response.
10. 10
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