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THE INTEGRATION OF SOLAR GENERATION ON A POWER SYSTEM: OPERATIONAL AND ECONOMIC EVALUATIONMarco A. Velastegui Andrade (5930348) 16 January 2019 (has links)
<p>In recent
years, the accelerated deployment of renewable electricity generation resources,
especially wind and photovoltaic (PV) solar, has added challenges to the
operation and planning of the power grid.
One of the challenges is that the variability of solar and wind power
output may increase the variation of the load that must be followed by
dispatchable resources and increase the ramping capacity needs. Moreover, the
decision about the configuration of a PV solar generation systems has
operational and economic implications because peak solar energy production does
not always precisely occur when the wholesale electricity prices of the system
are highest. Therefore, as the renewable capacity levels grow, it becomes increasingly
important to examine the potential impacts on the system cost and portfolio of
conventional generating units to respond to the intermittent nature of some
renewable generation technologies. Three related analyses explored in this dissertation
address some of the challenges of integrating utility-scale PV solar and wind
projects into a power system using a case study for Indiana.</p>
<p>The first
analysis identifies the optimal azimuth and tilt angles of solar PV
installations that alternatively maximize the annual electricity generation or
the economic value of the resource. The economic implications of the
configuration of solar PV installations within Indiana are estimated based on wholesale
prices of electricity and simulated solar output for different combinations of
angles and types of array installations. The results show that solar projects
across the state would need to have azimuth angles within the 177 and 182
degrees range to obtain maximum annual energy and 180 to 190.5 degrees to maximize
annual value, independently of their array types. Furthermore, southern and
northwestern zones showed the highest impacts from using an optimal angle
configuration of the solar installations. Nevertheless, on average, the
benefits in annual electricity generated or economic value from their
reconfiguration across the state are minor, amounting to less than one percent.
</p>
<p>The second
analysis explores the effects of additional solar and wind power investments on
the 2035 requirements for baseload and peaking generation capacity, the amount
of energy supplied by various types of generation technologies and the costs of
Indiana’s electric supply system. From a capacity planning and unit
commitment/dispatch perspective, the results of this analysis indicated that
with a portfolio that includes more solar and/or wind power generation, there
would be need to add new peaking generation units. However, the total need for
additional peaking resources declines as more renewables are added to the
generation mix. Because Indiana still heavily relies on coal and other baseload
resources to generate electricity, no new baseload capacity is required in the
future. Generally, additions of PV solar and wind capacity amplify the
variation in load net of renewable generation and create greater needs for
ramping services from conventional units. However, results of the analysis show
that the existing portfolio of conventional generation resources in Indiana
would have sufficient operational flexibility to be able to accommodate ramping
requirements even with PV solar and wind capacity penetration levels as high as
30% of total electricity generation. However, at those levels of renewables
capacity there are a times during the year when the optimal operational
strategy is to curtail solar and wind generation. From a technical perspective,
the results indicated that larger thermal generating units are used more for
load following and turned on and off (cycled) more frequently with the
additional renewables than without them but mainly during days with low levels
of demand and high levels of generation from renewable technologies. From the
cost perspective, the results of the model support the idea that it would be
cheaper in the long-term to invest in a combination of solar and wind
generation resources than in solar generation resources alone. Moreover, the
reductions in variable costs, driven by the zero variable cost added to the
system by the additional solar and wind capacity, were not sufficient to
outweigh the increases in capital costs regardless of the levels of capacity
additions. </p>
<p>For the
third analysis, the proposed capacity expansion model was used to estimate the
value of capacity of PV solar and PV solar in combination with wind capacity in
terms of baseload/peaking resources from a deterministic system peak load
reliability perspective and for various penetration levels of these resources. The
capacity values of solar, which refer to the contribution of PV solar plants to
reliably meeting the system peak demand, for all the wind capacity levels
analyzed, fall as the amount of solar capacity increases. This is because as
solar generation increases and closely coincides with the occurrence of the
system peak load, there is a shift of the peak load net of renewable generation
time to later afternoon hours, when solar installations begin to reduce their
production, therefore decreasing their contribution to reliably meeting system
peak demand. The calculated solar capacity values are between 2.7% and 67.3% of
the corresponding solar nameplate capacity considering all zones and types of
PV solar arrays in Indiana, and vary with the level of solar penetration. The
range of values obtained are in line with the ones found in other studies using
stochastic reliability-based methods.</p>
<p>This dissertation contributes to
the literature on the interaction between PV solar with other generation
resources and to their economic, operational and policy implications.
Furthermore, it provides another decision-making tool from a planning perspective
for policymakers, utility companies and project developers.</p>
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Design of wide-area damping control systems for power system low-frequency inter-area oscillationsZhang, Yang, January 2007 (has links) (PDF)
Thesis (Ph. D. in electrical engineering)--Washington State University, December 2007. / Includes bibliographical references (p. 135-146).
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An investigation of subsynchronous oscillation of AC/DC power systems modeling and analysis /Yu, Chang. January 2006 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.
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Evaluation of dynamically controlled resistive braking for the Pacific Northwest power systemRaschio, Peter J. 19 July 1994 (has links)
Today's power systems are undergoing dynamic changes in their operation.
The high cost of capital improvements that include new generation and transmission
projects has prompted power system planners to look for other alternatives in dealing
with increased loads and overall system growth. A dynamic braking resistor is a
device that allows for an increased rating of a transmission system's transient stability
limit. This allows increased power flows over existing transmission lines without the
need to build additional transmission facilities.
This thesis investigates the application of dynamically controlled resistive
braking in the Pacific Northwest power system. Specifically, possible control
alternatives, to replace the present dynamic brake control system at Chief Joseph
station, are examined. This examination includes determination of appropriate
locations for control system input, development of control algorithms, development of
computer and laboratory power system models, and testing and recommendations
based upon the developed control algorithms. / Graduation date: 1995
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Impact of optimally placed VAR support on electricity spot pricingKhajjayam, Ramesh Kumar V. January 2006 (has links)
Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains x, 105 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 99-105).
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Multi-Agent System for predictive reconfiguration of Shipboard Power SystemsSrivastava, Sanjeev Kumar 17 February 2005 (has links)
The electric power systems in U.S. Navy ships supply energy to sophisticated systems for weapons, communications, navigation and operation. The reliability and survivability of the Shipboard Power System (SPS) are critical to the mission of a surface combatant ship, especially under battle conditions. In the event of battle, various weapons might attack a ship. When a weapon hits the ship it can cause severe damage to the electrical system on the ship. This damage can lead to de-energization of critical loads on a ship that can eventually decrease a ships ability to survive the attack. It is very important, therefore, to maintain availability of energy to the connected loads that keep the power systems operational. Technology exists that enables the detection of an incoming weapon and prediction of the geographic area where the incoming weapon will hit the ship. This information can then be used to take reconfiguration actions before the actual hit so that the actual damage caused by the weapon hit is reduced. The Power System Automation Lab (PSAL) has proposed a unique concept called "Predictive Reconfiguration" which refers to performing reconfiguration of a ships power system before a weapon hit to reduce the potential damage to the electrical system caused by the impending weapon hit. The concept also includes reconfiguring the electrical system to restore power to as much of the healthy system as possible after the weapon hit. This dissertation presents a new methodology for Predictive Reconfiguration of a Shipboard Power System (SPS). This probabilistic approach includes a method to assess the damage that will be caused by a weapon hit. This method calculates the expected probability of damage for each electrical component on the ship. Also a heuristic method is included, which uses the expected probability of damage to determine reconfiguration steps to reconfigure the ships electrical network to reduce the damage caused by a weapon hit. This dissertation also presents a modified approach for performing a reconfiguration for restoration after the weapon hits the system. In this modified approach, an expert system based restoration method restores power to loads de-energized due to the weapon hit. These de-energized loads are restored in a priority order. The methods were implemented using multi-agent technology. A test SPS model based on the electrical layout of a non-nuclear surface combatant ship was presented. Complex scenarios representing electrical casualties caused due to a weapon hit, on the test SPS model, were presented. The results of the Predictive Reconfiguration methodology for complex scenarios were presented to illustrate the effectiveness of the developed methodology.
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Study of auxiliary power systemsfor offshore wind turbines : an extended analysis of a diesel gen-setsolutionBerggren, Joakim January 2013 (has links)
Until today the offshore wind power has grown in a steady pace and many new wind farms are being constructed around the globe. An important factor that is investigated today in the industry are the security of power supply to the equipment needed for controlling the offshore system during emergency situations. When a offshore wind farm is disconnected from the external grid and an emergency case occur the wind turbine generators lose their ability to transfer power and they are forced to be taken out of operation. As there are a number of loads in the wind turbines (navigation lights, sensor- and communication-apparatus, ventilation- and heating equipment etc.) they have a load demand which must be supplied in emergency mode. The German Transmission System operator (TSO) TenneT GmbH has set a requirement that the wind turbines is to be supplied by an auxiliary power supply (APS) in 12 hours and therefore there is need for a long-term auxiliary power supply system. This master thesis was assigned to investigate the most feasible APS-system. From the study of a number of different APS's one concept was chosen. This was the diesel gen-set solution placed on an offshore substation at sea. The system was modeled in the software DIgSILENT PowerFactory where a load flow analysis validated the calculated data and a study of the impact of transients in the system was performed.
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An Integrative Approach to Reliability Analysis of an IEC 61850 Digital SubstationZhang, Yan 1988- 14 March 2013 (has links)
In recent years, reliability evaluation of substation automation systems has received a significant attention from the research community. With the advent of the concept of smart grid, there is a growing trend to integrate more computation and communication technology into power systems.
This thesis focuses on the reliability evaluation of modern substation automation systems. Such systems include both physical devices (current carrying) such as lines, circuit breakers, and transformers, as well as cyber devices (Ethernet switches, intelligent electronic devices, and cables) and belong to a broader class of cyber-physical systems. We assume that the substation utilizes IEC 61850 standard, which is a dominant standard for substation automation.
Focusing on IEC 61850 standard, we discuss the failure modes and analyze their effects on the system. We utilize reliability block diagrams for analyzing the reliability of substation components (bay units) and then use the state space approach to study the effects at the substation level. Case study is based on an actual IEC 61850 substation automation system, with different network topologies consideration concluded.
Our analysis provides a starting point for evaluating the reliability of the substation and the effects of substation failures to the rest of the power system. By using the state space methods, the steady state probability of each failure effects were calculated in different bay units. These probabilities can be further used in the modeling of the composite power system to analyze the loss of load probabilities.
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A functional link network based adaptive power system stabilizerSrinivasan, Saradha 02 September 2011
<p>An on-line identifier using Functional Link Network (FLN) and Pole-shift (PS) controller for power system stabilizer (PSS) application are presented in this thesis. To have the satisfactory performance of the PSS controller, over a wide range of operating conditions, it is desirable to adapt PSS parameters in real time. Artificial Neural Networks (ANNs) transform the inputs in a low-dimensional space to high-dimensional nonlinear hidden unit space and they have the ability to model the nonlinear characteristics of the power system. The ability of ANNs to learn makes them more suitable for use in adaptive control techniques.</p>
<p>On-line identification obtains a mathematical model at each sampling period to track the dynamic behavior of the plant. The ANN identifier consisting of a Functional link Network (FLN) is used for identifying the model parameters. A FLN model eliminates the need of hidden layer while retaining the nonlinear mapping capability of the neural network by using enhanced inputs. This network may be conveniently used for function approximation with faster convergence rate and lesser computational load.</p>
<p>The most commonly used Pole Assignment (PA) algorithm for adaptive control purposes assign the pole locations to fixed locations within the unit circle in the z-plane. It may not be optimum for different operating conditions. In this thesis, PS type of adaptive control algorithm is used. This algorithm, instead of assigning the closed-loop poles to fixed locations within the unit circle in the z-plane, this algorithm assumes that the pole characteristic polynomial of the closed-loop system has the same form as the pole characteristic of the open-loop system and shifts the open-loop poles radially towards the centre of the unit circle in the z-plane by a shifting factor α according to some rules. In this control algorithm, no coefficients need to be tuned manually, so manual parameter tuning (which is a drawback in conventional power system stabilizer) is minimized. The PS control algorithm uses the on-line updated ARMA parameters to calculate the new closed-loop poles of the system that are always inside the unit circle in the z-plane.</p>
<p>Simulation studies on a single-machine infinite bus and on a multi-machine power system for various operating condition changes, verify the effectiveness of the combined model of FLN identifier and PS control in damping the local and multi-mode oscillations occurring in the system. Simulation studies prove that the APSSs have significant benefits over conventional PSSs: performance improvement and no requirement for parameter tuning.</p>
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Optimization of Asset Management and Power System Operation Based on Equipment PerformanceEndo, Fumihiro, Kanamitsu, Masaki, Shiomi, Ryo, Kojima, Hiroki, Hayakawa, Naoki, Okubo, Hitoshi 04 1900 (has links)
No description available.
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