Skip to main content

ASU Electronic Theses and Dissertations


This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.

In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.

Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.


Mime Type
  • application/pdf
Date Range
2010 2019


Reliable and secure operation of bulk power transmission system components is an important aspect of electric power engineering. Component failures in a transmission network can lead to serious consequences and impact system reliability. The operational health of the transmission assets plays a crucial role in determining the reliability of an electric grid. To achieve this goal, scheduled maintenance of bulk power system components is an important activity to secure the transmission system against unanticipated events. This thesis identifies critical transmission elements in a 500 kV transmission network utilizing a ranking strategy. The impact of the failure of transmission assets operated …

Contributors
Bhandari, Harsh Nandlal, Vittal, Vijay, Heydt, Gerald T, et al.
Created Date
2019

Distributed energy resources have experienced dramatic growth and are beginning to support a significant amount of customer loads. Power electronic converters are the primary interface between the grid and the distributed energy resources/storage and offer several advantages including fast control, flexibility and high efficiency. The efficiency and the power density by volume are important performance metrics of a power converter. Compact and high efficiency power converter is beneficial to the cost-effectiveness of the converter interfaced generations. In this thesis, a soft-switching technique is proposed to reduce the size of passive components in a grid-connected converter while maintaining a high power …

Contributors
Yu, Ziwei, Ayyanar, Raja, Vittal, Vijay, et al.
Created Date
2018

Until late 1970’s the primary focus in power system modeling has been largely directed towards power system generation and transmission. Over the years, the importance of load modeling grew and having an accurate representation of load played an important role in the planning and operation studies. With an emphasis on tackling the topic of load modeling, this thesis presents the following intermediary steps in developing accurate load models: 1. Synthesis of a three-phase standard feeder and load model using the measured voltages and currents, for events such as faults and feeder pickup cases, obtained at the head of the feeder. …

Contributors
Nekkalapu, Sameer, Vittal, Vijay, Undrill, John M, et al.
Created Date
2018

After a major disturbance, the power system response is highly dependent on protection schemes and system dynamics. Improving power systems situational awareness requires proper and simultaneous modeling of both protection schemes and dynamic characteristics in power systems analysis tools. Historical information and ex-post analysis of blackouts reaffirm the critical role of protective devices in cascading events, thereby confirming the necessity to represent protective functions in transient stability studies. This dissertation is aimed at studying the importance of representing protective relays in power system dynamic studies. Although modeling all of the protective relays within transient stability studies may result in a …

Contributors
Hedman, Mojdeh Khorsand, Vittal, Vijay, Ayyanar, Raja, et al.
Created Date
2017

The power system is the largest man-made physical network in the world. Performing analysis of a large bulk system is computationally complex, especially when the study involves engineering, economic and environmental considerations. For instance, running a unit-commitment (UC) over a large system involves a huge number of constraints and integer variables. One way to reduce the computational expense is to perform the analysis on a small equivalent (reduced) model instead on the original (full) model. The research reported here focuses on improving the network reduction methods so that the calculated results obtained from the reduced model better approximate the performance …

Contributors
Zhu, Yujia, Tylavsky, Daniel John, Vittal, Vijay, et al.
Created Date
2017

Alternate sources of energy such as wind, solar photovoltaic and fuel cells are coupled to the power grid with the help of solid state converters. Continued deregulation of the power sector coupled with favorable government incentives has resulted in the rapid growth of renewable energy sources connected to the distribution system at a voltage level of 34.5kV or below. Of late, many utilities are also investing in these alternate sources of energy with the point of interconnection with the power grid being at the transmission level. These converter interfaced generation along with their associated control have the ability to provide …

Contributors
Ramasubramanian, Deepak, Vittal, Vijay, Undrill, John, et al.
Created Date
2017

Electric power system security assessment is one of the most important requirements for operational and resource planning of the bulk power system ensuring safe operation of the power system for all credible contingencies. This deterministic approach usually provides a conservative criterion and can result in expensive bulk system expansion plans or conservative operating limits. Furthermore, with increased penetration of converter-based renewable generation in the electric grid, the dynamics of the grid are changing. In addition, the variability and intermittency associated with the renewable energy sources introduce uncertainty in the electricity grid. Since security margins have direct economic impact on the …

Contributors
Datta, Sohom, Vittal, Vijay, Undrill, John, et al.
Created Date
2017

Two significant trends of recent power system evolution are: (1) increasing installa-tion of dynamic loads and distributed generation resources in distribution systems; (2) large-scale renewable energy integration at the transmission system level. A majority of these devices interface with power systems through power electronic converters. However, existing transient stability (TS) simulators are inadequate to represent the dynamic behavior of these devices accurately. On the other hand, simulating a large system using an electromagnetic transient (EMT) simulator is computationally impractical. EMT-TS hybrid simulation approach is an alternative to address these challenges. Furthermore, to thoroughly analyze the increased interactions among the transmission …

Contributors
Huang, Qiuhua, Vittal, Vijay, Undrill, John M., et al.
Created Date
2016

The standard optimal power flow (OPF) problem is an economic dispatch (ED) problem combined with transmission constraints, which are based on a static topology. However, topology control (TC) has been proposed in the past as a corrective mechanism to relieve overloads and voltage violations. Even though the benefits of TC are presented by several research works in the past, the computational complexity associated with TC has been a major deterrent to its implementation. The proposed work develops heuristics for TC and investigates its potential to improve the computational time for TC for various applications. The objective is to develop computationally …

Contributors
Balasubramanian, Pranavamoorthy, Hedman, Kory W, Vittal, Vijay, et al.
Created Date
2016

Present distribution infrastructure is designed mainly for uni-directional power flow with well-controlled generation. An increase in the inverter-interfaced photovoltaic (PV) systems requires a thorough re-examination of the design, operation, protection and control of distribution systems. In order to understand the impact of high penetration of PV generation, this work conducts an automated and detailed modeling of a power distribution system. The simulation results of the modeled distribution feeder have been verified with the field measurements. Based on the feeder model, this work studies the impact of the PV systems on voltage profiles under various scenarios, including reallocation of the PV …

Contributors
Tang, Yingying, Ayyanar, Raja, Karady, George, et al.
Created Date
2016

The grounding system in a substation is used to protect personnel and equipment. When there is fault current injected into the ground, a well-designed grounding system should disperse the fault current into the ground in order to limit the touch potential and the step potential to an acceptable level defined by the IEEE Std 80. On the other hand, from the point of view of economy, it is desirable to design a ground grid that minimizes the cost of labor and material. To design such an optimal ground grid that meets the safety metrics and has the minimum cost, an …

Contributors
Li, Songyan, Tylavsky, Daniel J., Ayyanar, Raja, et al.
Created Date
2016

Constraint relaxation by definition means that certain security, operational, or financial constraints are allowed to be violated in the energy market model for a predetermined penalty price. System operators utilize this mechanism in an effort to impose a price-cap on shadow prices throughout the market. In addition, constraint relaxations can serve as corrective approximations that help in reducing the occurrence of infeasible or extreme solutions in the day-ahead markets. This work aims to capture the impact constraint relaxations have on system operational security. Moreover, this analysis also provides a better understanding of the correlation between DC market models and AC …

Contributors
Salloum, Ahmed, Vittal, Vijay, Hedman, Kory, et al.
Created Date
2016

The past decades have seen a significant shift in the expectations and requirements re-lated to power system analysis tools. Investigations into major power grid disturbances have suggested the need for more comprehensive assessment methods. Accordingly, sig-nificant research in recent years has focused on the development of better power system models and efficient techniques for analyzing power system operability. The work done in this report focusses on two such topics 1. Analysis of load model parameter uncertainty and sensitivity based pa-rameter estimation for power system studies 2. A systematic approach to n-1-1 analysis for power system security as-sessment To assess the …

Contributors
Mitra, Parag, Vittal, Vijay, Heydt, Gerald T, et al.
Created Date
2016

This thesis provides a cost to benefit assessment of the proposed next generation distribution system, the Future Renewable Electric Energy Distribution Management (FREEDM) system. In this thesis, a probabilistic study is conducted to determine the payback period for an investment made in the FREEDM distribution system. The stochastic study will help in performing a detailed analysis in estimating the probability density function and statistics associated with the payback period. This thesis also identifies several parameters associated with the FREEDM system, which are used in the cost benefit study to evaluate the investment and several direct and indirect benefits. Different topologies …

Contributors
Dinakar, Abhishek, Heydt, Gerald T, Vittal, Vijay, et al.
Created Date
2016

This research mainly focuses on improving the utilization of photovoltaic (PV) re-sources in distribution systems by reducing their variability and uncertainty through the integration of distributed energy storage (DES) devices, like batteries, and smart PV in-verters. The adopted theoretical tools include statistical analysis and convex optimization. Operational issues have been widely reported in distribution systems as the penetration of PV resources has increased. Decision-making processes for determining the optimal allo-cation and scheduling of DES, and the optimal placement of smart PV inverters are con-sidered. The alternating current (AC) power flow constraints are used in these optimiza-tion models. The first two …

Contributors
Li, Qifeng, Vittal, Vijay, Heydt, Gerald T, et al.
Created Date
2016

This dissertation presents innovative techniques to develop performance-based models and complete transient models of induction motor drive systems with vector controls in electro-magnetic transient (EMT) and positive sequence transient stability (PSTS) simulation programs. The performance-based model is implemented by obtaining the characteristic transfer functions of perturbed active and reactive power consumptions with respect to frequency and voltage perturbations. This level of linearized performance-based model is suitable for the investigation of the damping of small-magnitude low-frequency oscillations. The complete transient model is proposed by decomposing the motor, converter and control models into d-q axes components and developing a compatible electrical interface …

Contributors
Liu, Yuan, Vittal, Vijay, Undrill, John, et al.
Created Date
2016

An increase in the number of inverter-interfaced photovoltaic (PV) generators on existing distribution feeders affects the design, operation, and control of the distri- bution systems. Existing distribution system analysis tools are capable of supporting only snapshot and quasi-static analyses. Capturing the dynamic effects of the PV generators during the variation in the distribution system states is necessary when studying the effects of controller bandwidths, multiple voltage correction devices, and anti-islanding. This work explores the use of dynamic phasors and differential algebraic equations (DAE) for impact analysis of the PV generators on the existing distribution feeders. The voltage unbalance induced by …

Contributors
Nagarajan, Adarsh, Ayyanar, Raja, Vittal, Vijay, et al.
Created Date
2015

Corrective transmission topology control schemes are an essential part of grid operations and are used to improve the reliability of the grid as well as the operational efficiency. However, topology control schemes are frequently established based on the operator's past knowledge of the system as well as other ad-hoc methods. This research presents robust corrective topology control, which is a transmission switching methodology used for system reliability as well as to facilitate renewable integration. This research presents three topology control (corrective transmission switching) methodologies along with the detailed formulation of robust corrective switching. The robust model can be solved off-line …

Contributors
Korad, Akshay Shashikumar, Hedman, Kory W, Ayyanar, Raja, et al.
Created Date
2015

An important operating aspect of all transmission systems is power system stability and satisfactory dynamic performance. The integration of renewable resources in general, and photovoltaic resources in particular into the grid has created new engineering issues. A particularly problematic operating scenario occurs when conventional generation is operated at a low level but photovoltaic solar generation is at a high level. Significant solar photovoltaic penetration as a renewable resource is becoming a reality in some electric power systems. In this thesis, special attention is given to photovoltaic generation in an actual electric power system: increased solar penetration has resulted in significant …

Contributors
Pethe, Anushree Sanjeev, Vittal, Vijay, Heydt, Gerald T, et al.
Created Date
2015

The development of new policies favoring integration of renewable energy into the grid has created a need to relook at our existing infrastructure resources and at the way the power system is currently operated. Also, the needs of electric energy markets and transmission/generation expansion planning has created a niche for development of new computationally efficient and yet reliable, simple and robust power flow tools for such studies. The so called dc power flow algorithm is an important power flow tool currently in use. However, the accuracy and performance of dc power flow results is highly variable due to the various …

Contributors
Sood, Puneet, Tylavsky, Daniel J, Vittal, Vijay, et al.
Created Date
2014

There has been a considerable growth in distributed photovoltaic (PV) genera-tion and its integration in electric power distribution systems. This has led to a change in the distribution system infrastructure. Properly planned distributed gen-eration can offer a variety of benefits for system operations and enhance opera-tional performance of the distribution system. However, high penetration of PV resources can give rise to operating conditions which do not arise in traditional systems and one of the potential issues that needs to be addressed involves impact on power quality of the system with respect to the spectral distortion in voltages and currents. The …

Contributors
Joshi, Titiksha Vjay, Heydt, Gerald T, Ayyanar, Raja, et al.
Created Date
2014

At present, almost 70% of the electric energy in the United States is produced utilizing fossil fuels. Combustion of fossil fuels contributes CO2 to the atmosphere, potentially exacerbating the impact on global warming. To make the electric power system (EPS) more sustainable for the future, there has been an emphasis on scaling up generation of electric energy from wind and solar resources. These resources are renewable in nature and have pollution free operation. Various states in the US have set up different goals for achieving certain amount of electrical energy to be produced from renewable resources. The Southwestern region of …

Contributors
Prakash, Nitin, Heydt, Gerald T., Vittal, Vijay, et al.
Created Date
2013

Insulation aging monitoring is widely used to evaluate the operating condition of power equipment. One important monitoring method is detecting partial discharges (PD). PD is a localized breakdown of dielectric and its characteristics can give information about the insulation aging. Most existing test methods cannot identify different kinds of defects. Also, the practical application of PD detection in most existing test methods is restricted by weak PD signals and strong electric field disturbance from surroundings. In order to monitor aging situation in detail, types of PDs are important features to take into account. To classify different types of PDs, pulse …

Contributors
Cui, Longfei, Gorur, Ravi, Vittal, Vijay, et al.
Created Date
2013

In modern electric power systems, energy management systems (EMSs) are responsi-ble for monitoring and controlling the generation system and transmission networks. State estimation (SE) is a critical `must run successful' component within the EMS software. This is dictated by the high reliability requirements and need to represent the closest real time model for market operations and other critical analysis functions in the EMS. Tradi-tionally, SE is run with data obtained only from supervisory control and data acquisition (SCADA) devices and systems. However, more emphasis on improving the performance of SE drives the inclusion of phasor measurement units (PMUs) into SE …

Contributors
Murugesan, Veerakumar, Vittal, Vijay, Heydt, Gerald, et al.
Created Date
2013

The past few decades have seen a consistent growth of distributed PV sources. Distributed PV, like other DG sources, can be located at or near load centers and provide benefits which traditional generation may lack. However, distribution systems were not designed to accommodate such power generation sources as these sources might lead to operational as well as power quality issues. A high penetration of distributed PV resources may lead to bi-directional power flow resulting in voltage swells, increased losses and overloading of conductors. Voltage unbalance is a concern in distribution systems and the effect of single-phase residential PV systems on …

Contributors
Mitra, Parag, Heydt, Gerald T, Vittal, Vijay, et al.
Created Date
2013

This thesis presents a new technique to develop an air-conditioner (A/C) compressor single phase induction motor model for use in an electro-magnetic transient program (EMTP) simulation tool. The method developed also has the capability to represent multiple units of the component in a specific three-phase distribution feeder and investigate the phenomenon of fault-induced delayed voltage recovery (FIDVR) and the cause of motor stalling. The system of differential equations representing the single phase induction motor model is developed and formulated. Implicit backward Euler method is applied to numerically integrate the stator currents that are to be drawn from the electric network. …

Contributors
Liu, Yuan, Vittal, Vijay, Undrill, John, et al.
Created Date
2012

The Smart Grid initiative describes the collaborative effort to modernize the U.S. electric power infrastructure. Modernization efforts incorporate digital data and information technology to effectuate control, enhance reliability, encourage small customer sited distributed generation (DG), and better utilize assets. The Smart Grid environment is envisioned to include distributed generation, flexible and controllable loads, bidirectional communications using smart meters and other technologies. Sensory technology may be utilized as a tool that enhances operation including operation of the distribution system. Addressing this point, a distribution system state estimation algorithm is developed in this thesis. The state estimation algorithm developed here utilizes distribution …

Contributors
Haughton, Daniel Andrew, Heydt, Gerald T, Vittal, Vijay, et al.
Created Date
2012

Photovoltaic (PV) power generation has the potential to cause a significant impact on power system reliability since its total installed capacity is projected to increase at a significant rate. PV generation can be described as an intermittent and variable resource because its production is influenced by ever-changing environmental conditions. The study in this dissertation focuses on the influence of PV generation on trans-mission system reliability. This is a concern because PV generation output is integrated into present power systems at various voltage levels and may significantly affect the power flow patterns. This dissertation applies a probabilistic power flow (PPF) algorithm …

Contributors
Fan, Miao, Vittal, Vijay, Heydt, Gerald Thomas, et al.
Created Date
2012

Electric power systems are facing great challenges from environmental regulations, changes in demand due to new technologies like electric vehicle, as well as the integration of various renewable energy sources. These factors taken together require the development of new tools to help make policy and investment decisions for the future power grid. The requirements of a network equivalent to be used in such planning tools are very different from those assumed in the development of traditional equivalencing procedures. This dissertation is focused on the development, implementation and verification of two network equivalencing approaches on large power systems, such as the …

Contributors
Shi, Di, Tylavsky, Daniel J, Vittal, Vijay, et al.
Created Date
2012

In electric power systems, phasor measurement units (PMUs) are capable of providing synchronized voltage and current phasor measurements which are superior to conventional measurements collected by the supervisory control and data acquisition (SCADA) system in terms of resolution and accuracy. These measurements are known as synchrophasor measurements. Considerable research work has been done on the applications of PMU measurements based on the as-sumption that a high level of accuracy is obtained in the field. The study in this dissertation is conducted to address the basic issue concerning the accuracy of actual PMU measurements in the field. Synchronization is one of …

Contributors
Zhang, Qing, Heydt, Gerald, Vittal, Vijay, et al.
Created Date
2012

This thesis concerns with the impact of renewable generation resources on the power system stability. The rapidly increasing integration of renewable energy sources into the grid can change the way power systems operate and respond to system disturbances. This is because the available inertia from synchronous machines, which helps in damping system oscillations, gets reduced as an increase in renewables like wind and solar photovoltaics is accompanied by a decrease in conventional generators. This aspect of high penetration of renewables has the potential to affect the rotor angle stability and small signal stability of power systems. The system with increased …

Contributors
Singh, Iknoor, Vittal, Vijay, Ayyanar, Raja, et al.
Created Date
2012

In the deregulated power system, locational marginal prices are used in transmission engineering predominantly as near real-time pricing signals. This work extends this concept to distribution engineering so that a distribution class locational marginal price might be used for real-time pricing and control of advanced control systems in distribution circuits. A formulation for the distribution locational marginal price signal is presented that is based on power flow sensitivities in a distribution system. A Jacobian-based sensitivity analysis has been developed for application in the distribution pricing method. Increasing deployment of distributed energy sources is being seen at the distribution level and …

Contributors
Ranganathan Sathyanarayana, Bharadwaj, Heydt, Gerald T, Vittal, Vijay, et al.
Created Date
2012

Voltage stability is always a major concern in power system operation. Recently Fault Induced Delayed Voltage Recovery (FIDVR) has gained increased attention. It is widely believed that the motor-driven loads of high efficiency, low inertia air conditioners are one of the main causes of FIDVR events. Simulation tools that assist power system operation and planning have been found insufficient to reproduce FIDVR events. This is because of their inaccurate load modeling of single-phase motor loads. Conventionally three-phase motor models have been used to represent the aggregation effect of single-phase motor load. However researchers have found that this modeling method is …

Contributors
Ma, Yan, Karady, George G, Vittal, Vijay, et al.
Created Date
2012

This thesis concerns the impact of energy storage on the power system. The rapidly increasing integration of renewable energy source into the grid is driving greater attention towards electrical energy storage systems which can serve many applications like economically meeting peak loads, providing spinning reserve. Economic dispatch is performed with bulk energy storage with wind energy penetration in power systems allocating the generation levels to the units in the mix, so that the system load is served and most economically. The results obtained in previous research to solve for economic dispatch uses a linear cost function for a Direct Current …

Contributors
Gupta, Samir, Heydt, Gerald T, Vittal, Vijay, et al.
Created Date
2012

This thesis is focused on the study of wind energy integration and is divided into two segments. The first part of the thesis deals with developing a reliability evaluation technique for a wind integrated power system. A multiple-partial outage model is utilized to accurately calculate the wind generation availability. A methodology is presented to estimate the outage probability of wind generators while incorporating their reduced power output levels at low wind speeds. Subsequently, power system reliability is assessed by calculating the loss of load probability (LOLP) and the effect of wind integration on the overall system is analyzed. Actual generation …

Contributors
Sinha, Anubhav, Heydt, Gerald T, Vittal, Vijay, et al.
Created Date
2012

Due to restructuring and open access to the transmission system, modern electric power systems are being operated closer to their operational limits. Additionally, the secure operational limits of modern power systems have become increasingly difficult to evaluate as the scale of the network and the number of transactions between utilities increase. To account for these challenges associated with the rapid expansion of electric power systems, dynamic equivalents have been widely applied for the purpose of reducing the computational effort of simulation-based transient security assessment. Dynamic equivalents are commonly developed using a coherency-based approach in which a retained area and an …

Contributors
Ma, Feng, Vittal, Vijay, Tylavsky, Daniel, et al.
Created Date
2011

Recent changes in the energy markets structure combined with the conti-nuous load growth have caused power systems to be operated under more stressed conditions. In addition, the nature of power systems has also grown more complex and dynamic because of the increasing use of long inter-area tie-lines and the high motor loads especially those comprised mainly of residential single phase A/C motors. Therefore, delayed voltage recovery, fast voltage collapse and short term voltage stability issues in general have obtained significant importance in relia-bility studies. Shunt VAr injection has been used as a countermeasure for voltage instability. However, the dynamic and …

Contributors
Salloum, Ahmed, Vittal, Vijay, Heydt, Gerald, et al.
Created Date
2011

All-dielectric self-supporting (ADSS) fiber optic cables are used for data transfer by the utilities. They are installed along high voltage transmission lines. Dry band arcing, a phenomenon which is observed in outdoor insulators, is also observed in ADSS cables. The heat developed during dry band arcing damages the ADSS cables' outer sheath. A method is presented here to rate the cable sheath using the power developed during dry band arcing. Because of the small diameter of ADSS cables, mechanical vibration is induced in ADSS cable. In order to avoid damage, vibration dampers known as spiral vibration dampers (SVD) are used …

Contributors
Prabakar, Kumaraguru, Karady, George G, Vittal, Vijay, et al.
Created Date
2011

The high penetration of photovoltaic (PV) both at the utility and at the distribu-tion levels, has raised concerns about the reliability of grid-tied inverters of PV power systems. Inverters are generally considered as the weak link in PV power systems. The lack of a dedicated qualification/reliability standard for PV inverters is a main barrier in realizing higher level of confidence in reliability. Development of a well-accepted design qualification standard specifically for PV inverters will help pave the way for significant improvement in reliability and performance of inverters across the entire industry. The existing standards for PV inverters such as UL …

Contributors
Alampoondi Venkataramanan, Sai Balasubramanian, Ayyanar, Raja, Vittal, Vijay, et al.
Created Date
2011

An advantage of doubly fed induction generators (DFIGs) as compared to conventional fixed speed wind turbine generators is higher efficiency. This higher efficiency is achieved due to the ability of the DFIG to operate near its optimal turbine efficiency over a wider range of wind speeds through variable speed operation. This is achieved through the application of a back-to-back converter that tightly controls the rotor current and allows for asynchronous operation. In doing so, however, the power electronic converter effectively decouples the inertia of the turbine from the system. Hence, with the increase in penetration of DFIG based wind farms, …

Contributors
Gautam, Durga, Vittal, Vijay, Heydt, Gerald, et al.
Created Date
2010

Market acceptability of distributed energy resource (DER) technologies and the gradual and consistent increase in their depth of penetration have generated significant interest over the past few years. In particular, in Arizona and several other states there has been a substantial in-crease in distributed photovoltaic (PV) generation interfaced to the power distribution systems, and is expected to continue to grow at a significant rate. This has made integration, control and optimal operation of DER units a main area of focus in the design and operation of distribution systems. Grid-connected, distributed PV covers a wide range of power levels ranging from …

Contributors
Narayanan, Anand, Ayyanar, Raja, Vittal, Vijay, et al.
Created Date
2010