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- Genre: Masters Thesis
- Creators: Karady, George G.
Description
Prior work in literature has illustrated the benefits of using surge arrester as a way to improve the lighting performance of the substation and transmission line. Installing surge arresters would enhance the system reliability but it comes with an extra capital expenditure. This thesis provides simulation analysis to examine substation-specific applications of surge arrester as a way of determining the optimal, cost-effective placement of surge arresters. Four different surge arrester installation configurations are examined for the 500/230 kV Rudd substation which belongs to the utility, Salt River Project (SRP). The most efficient configuration is identified in this thesis. A new method “voltage-distance curve” is proposed in this work to evaluate different surge arrester installation configurations. Simulation results show that surge arresters only need to be equipped on certain location of the substation and can still ensure sufficient lightning protection.
With lower tower footing resistance, the lightning performance of the transmission line can typically be improved. However, when surge arresters are installed in the system, the footing resistance may have either negative or positive effect on the lightning performance. Different situations for both effects are studied in this thesis.
This thesis proposes a surge arrester installation strategy for the overhead transmission line lightning protection. In order to determine the most efficient surge arrester configuration of transmission line, the entire transmission line is divided into several line sections according to the footing resistance of its towers. A line section consists of the towers which have similar footing resistance. Two different designs are considered for transmission line lightning protection, they include: equip different number of surge arrester on selected phase of every tower, equip surge arresters on all phases of selected towers. By varying the number of the towers or the number of phases needs to be equipped with surge arresters, the threshold voltage for line insulator flashover is used to evaluate different surge arrester installation configurations. The way to determine the optimal surge arresters configuration for each line section is then introduced in this thesis.
With lower tower footing resistance, the lightning performance of the transmission line can typically be improved. However, when surge arresters are installed in the system, the footing resistance may have either negative or positive effect on the lightning performance. Different situations for both effects are studied in this thesis.
This thesis proposes a surge arrester installation strategy for the overhead transmission line lightning protection. In order to determine the most efficient surge arrester configuration of transmission line, the entire transmission line is divided into several line sections according to the footing resistance of its towers. A line section consists of the towers which have similar footing resistance. Two different designs are considered for transmission line lightning protection, they include: equip different number of surge arrester on selected phase of every tower, equip surge arresters on all phases of selected towers. By varying the number of the towers or the number of phases needs to be equipped with surge arresters, the threshold voltage for line insulator flashover is used to evaluate different surge arrester installation configurations. The way to determine the optimal surge arresters configuration for each line section is then introduced in this thesis.
ContributorsXia, Qianxue (Author) / Karady, George G. (Thesis advisor) / Ayyanar, Raja (Committee member) / Lei, Qin (Committee member) / Arizona State University (Publisher)
Created2018
Description
On-line dynamic security assessment (DSA) analysis has been developed and applied in several power dispatching control centers. Existing applications of DSA systems are limited by the assumption of the present system operating conditions and computational speeds. To overcome these obstacles, this research developed a novel two-stage DSA system to provide periodic security prediction in real time. The major contribution of this research is to develop an open source on-line DSA system incorporated with Phasor Measurement Unit (PMU) data and forecast load. The pre-fault prediction of the system can provide more accurate assessment of the system and minimize the disadvantage of a low computational speed of time domain simulation.
This Thesis describes the development of the novel two-stage on-line DSA scheme using phasor measurement and load forecasting data. The computational scheme of the new system determines the steady state stability and identifies endangerments in a small time frame near real time. The new on-line DSA system will periodically examine system status and predict system endangerments in the near future every 30 minutes. System real-time operating conditions will be determined by state estimation using phasor measurement data. The assessment of transient stability is carried out by running the time-domain simulation using a forecast working point as the initial condition. The forecast operating point is calculated by DC optimal power flow based on forecast load.
This Thesis describes the development of the novel two-stage on-line DSA scheme using phasor measurement and load forecasting data. The computational scheme of the new system determines the steady state stability and identifies endangerments in a small time frame near real time. The new on-line DSA system will periodically examine system status and predict system endangerments in the near future every 30 minutes. System real-time operating conditions will be determined by state estimation using phasor measurement data. The assessment of transient stability is carried out by running the time-domain simulation using a forecast working point as the initial condition. The forecast operating point is calculated by DC optimal power flow based on forecast load.
ContributorsWang, Qiushi (Author) / Karady, George G. (Thesis advisor) / Pal, Anamitra (Committee member) / Holbert, Keith E. (Committee member) / Arizona State University (Publisher)
Created2017
Description
The government support towards green energy sources for the better future of the planet has changed the perspective of the people towards the usage of green energy. Among renewables, solar is one of the important and easily accessible resources to convert energy from the sun directly into electricity and this system has gained fame since the past three decades.
SRP has set up a 6.36 kW PV and 19.4 kWh battery system on the rooftop of Engineering Research Center (ERC). The system is grid-connected and ASU (Arizona State University) has developed two load banks with a minimum step of 72 watts to simulate different residential load profiles and perform other research objectives.
A customer benefit analysis is performed for residential customers with photovoltaic (PV) systems and energy storage particularly in the state of Arizona. By optimizing the use of energy storage device, the algorithm aims at maximizing the profit and minimizing utility bills in accordance with the demand charge algorithm of the local utility. This part of the research has been published as a conference paper in IEEE PES General Meeting 2017.
A transient test is performed on the PV-battery during the on-grid mode and the off-grid mode to study the system behaviour during the transients. An algorithm is developed by the ASU research team to minimize the demand charge tariff for the residential customers. A statistical analysis is performed on the data collected from the system using a MATLAB algorithm.
SRP has set up a 6.36 kW PV and 19.4 kWh battery system on the rooftop of Engineering Research Center (ERC). The system is grid-connected and ASU (Arizona State University) has developed two load banks with a minimum step of 72 watts to simulate different residential load profiles and perform other research objectives.
A customer benefit analysis is performed for residential customers with photovoltaic (PV) systems and energy storage particularly in the state of Arizona. By optimizing the use of energy storage device, the algorithm aims at maximizing the profit and minimizing utility bills in accordance with the demand charge algorithm of the local utility. This part of the research has been published as a conference paper in IEEE PES General Meeting 2017.
A transient test is performed on the PV-battery during the on-grid mode and the off-grid mode to study the system behaviour during the transients. An algorithm is developed by the ASU research team to minimize the demand charge tariff for the residential customers. A statistical analysis is performed on the data collected from the system using a MATLAB algorithm.
ContributorsEtha, Pavan (Author) / Karady, George G. (Thesis advisor) / Heydt, Gerald (Committee member) / Ayyanar, Raja (Committee member) / Grant, Smedley (Committee member) / Arizona State University (Publisher)
Created2017
Description
With the penetration of distributed renewable energy and the development of
semiconductor technology, power electronic devices could be utilized to interface re-
newable energy generation and the distribution power grid. However, when directly
connected to the power grid, the semiconductors inside the power electronic devices
could be vulnerable to the power system transient, especially to lightning strikes.
The work of this research focuses on the insulation coordination of power elec-
tronic devices connected directly to the power distribution system. The Solid State
Transformer (SST) in Future Renewable Electric Energy Delivery and Management
(FREEDM) system could be a good example for grid connected power electronic
devices. Simulations were conducted in Power Systems Computer Aided Design
(PSCAD) software. A simulation done to the FREEDM SST showed primary re-
sults which were then compare to simulation done to the grid-connected operating
Voltage Source Converter (VSC) to get more objective results.
Based on the simulation results, voltage surges caused by lightning strikes could
result in damage on the grid-connected electronic devices. Placing Metal Oxide Surge
Arresers (MOSA, also known as Metal Oxide Surge Varistor, MOV) at the front lter
could provide eective protection for those devices from power transient. Part of this
research work was published as a conference paper and was presented at CIGRE US
National Conference: Grid of the Future Symposium [1] and North American Power
Symposium [2].
semiconductor technology, power electronic devices could be utilized to interface re-
newable energy generation and the distribution power grid. However, when directly
connected to the power grid, the semiconductors inside the power electronic devices
could be vulnerable to the power system transient, especially to lightning strikes.
The work of this research focuses on the insulation coordination of power elec-
tronic devices connected directly to the power distribution system. The Solid State
Transformer (SST) in Future Renewable Electric Energy Delivery and Management
(FREEDM) system could be a good example for grid connected power electronic
devices. Simulations were conducted in Power Systems Computer Aided Design
(PSCAD) software. A simulation done to the FREEDM SST showed primary re-
sults which were then compare to simulation done to the grid-connected operating
Voltage Source Converter (VSC) to get more objective results.
Based on the simulation results, voltage surges caused by lightning strikes could
result in damage on the grid-connected electronic devices. Placing Metal Oxide Surge
Arresers (MOSA, also known as Metal Oxide Surge Varistor, MOV) at the front lter
could provide eective protection for those devices from power transient. Part of this
research work was published as a conference paper and was presented at CIGRE US
National Conference: Grid of the Future Symposium [1] and North American Power
Symposium [2].
ContributorsRong, Xuening (Author) / Karady, George G. (Thesis advisor) / Heydt, Gerald T (Committee member) / Ayyanar, Raja (Committee member) / Arizona State University (Publisher)
Created2017
Description
A robust, fast and accurate protection system based on pilot protection concept was developed previously and a few alterations in that algorithm were made to make it faster and more reliable and then was applied to smart distribution grids to verify the results for it. The new 10 sample window method was adapted into the pilot protection program and its performance for the test bed system operation was tabulated. Following that the system comparison between the hardware results for the same algorithm and the simulation results were compared. The development of the dual slope percentage differential method, its comparison with the 10 sample average window pilot protection system and the effects of CT saturation on the pilot protection system are also shown in this thesis. The implementation of the 10 sample average window pilot protection system is done to multiple distribution grids like Green Hub v4.3, IEEE 34, LSSS loop and modified LSSS loop. Case studies of these multi-terminal model are presented, and the results are also shown in this thesis. The result obtained shows that the new algorithm for the previously proposed protection system successfully identifies fault on the test bed and the results for both hardware and software simulations match and the response time is approximately less than quarter of a cycle which is fast as compared to the present commercial protection system and satisfies the FREEDM system requirement.
ContributorsIyengar, Varun (Author) / Karady, George G. (Thesis advisor) / Ayyanar, Raja (Committee member) / Holbert, Keith E. (Committee member) / Arizona State University (Publisher)
Created2014
Description
This research aims to investigate the effect of campus courtyards on students’ satisfaction with education. It will look into two different types of courtyard within the Arizona State University. One courtyard space has more elements and attributes of biophilic design and the other has less. In addition, this paper will provide guidelines for designing courtyards that would improve student’s satisfaction with education. The Methodology used is survey handouts to students after the researcher selects the two types of courtyards by observation. The participant in this study are randomly picked young adult college students (n=60). The results indicate a positive effect of biophilic design on student’s satisfaction with education in courtyards. Furthermore, guidelines for designing courtyards based on biophilic design elements and attributes are suggested.
ContributorsNaseef, Rawan Ahmed (Author) / Brunner, Lori (Thesis advisor) / Brooks, Kenneth (Committee member) / Bochart, Sonja (Committee member) / Arizona State University (Publisher)
Created2019
Description
The inherent intermittency in solar energy resources poses challenges to scheduling generation, transmission, and distribution systems. Energy storage devices are often used to mitigate variability in renewable asset generation and provide a mechanism to shift renewable power between periods of the day. In the absence of storage, however, time series forecasting techniques can be used to estimate future solar resource availability to improve the accuracy of solar generator scheduling. The knowledge of future solar availability helps scheduling solar generation at high-penetration levels, and assists with the selection and scheduling of spinning reserves. This study employs statistical techniques to improve the accuracy of solar resource forecasts that are in turn used to estimate solar photovoltaic (PV) power generation. The first part of the study involves time series forecasting of the global horizontal irradiation (GHI) in Phoenix, Arizona using Seasonal Autoregressive Integrated Moving Average (SARIMA) models. A comparative study is completed for time series forecasting models developed with different time step resolutions, forecasting start time, forecasting time horizons, training data, and transformations for data measured at Phoenix, Arizona. Approximately 3,000 models were generated and evaluated across the entire study. One major finding is that forecasted values one day ahead are near repeats of the preceding day—due to the 24-hour seasonal differencing—indicating that use of statistical forecasting over multiple days creates a repeating pattern. Logarithmic transform data were found to perform poorly in nearly all cases relative to untransformed or square-root transform data when forecasting out to four days. Forecasts using a logarithmic transform followed a similar profile as the immediate day prior whereas forecasts using untransformed and square-root transform data had smoother daily solar profiles that better represented the average intraday profile. Error values were generally lower during mornings and evenings and higher during midday. Regarding one-day forecasting and shorter forecasting horizons, the logarithmic transformation performed better than untransformed data and square-root transformed data irrespective of forecast horizon for data resolutions of 1-hour, 30-minutes, and 15-minutes.
ContributorsSoundiah Regunathan Rajasekaran, Dhiwaakar Purusothaman (Author) / Johnson, Nathan G (Thesis advisor) / Karady, George G. (Thesis advisor) / Ayyanar, Raja (Committee member) / Arizona State University (Publisher)
Created2016