George Gross - Profile on Academia.edu (original) (raw)
Papers by George Gross
International Journal of Electrical Power & Energy Systems, 1991
In the competitive environment in which US utilities operate, auctions are becoming an accepted m... more In the competitive environment in which US utilities operate, auctions are becoming an accepted means .[or procuring resources to meet utilities 'projected needs. The rationale/'or instituting auctions is to effectively harness the competitive forces in electricity resource markets in order to implement least-cost planning objectives. PG&E, in cooperation with the other Cal(fornia investor-owned utilities. Southern Cal(/brnia Edison and San Diego Gas and Eh, ctric, has developed a muhi-attribute auction ./i'amework /or the procurement o/./hture resources. The Ji'amework uses the attributes o['capacity and energy price, dispatehability, location, start date flexibilio', price tfiversity, pro/ect viability and environmental impacts to evaluate customer benefits. This allows comparability between and trade~ff~s" among attributes. Other ke)' features include the use q/ multiple scenarios to explieitO' account ./i~r ./uel price and load growth uncertainty, the explicit evaluation qf long-term impacts and dynamic operating benefits q/'dispatchability, and the use ~['port/blio theory ./or the evaluation Of price diversity. The.bidding evaluation also uses optimal power flow derived loss adjustment .factors and incremental network reinlorcement costs and takes into account uncertainty in determining start-date flexibility. The ./i'amework is sz{~'eiently general to be usab[e not only Jm" auctions, but also.[or utility evaluation of maintenance, power contracts and other investment decisions. This paper describes the ./kamework and its implementation into a PC spreddsheet so/'tware package.
2006 IEEE Power Engineering Society General Meeting, 2006
The panel chair George Gross and the seven panelists from different parts of the world aim to sum... more The panel chair George Gross and the seven panelists from different parts of the world aim to summarize the key aspects of research collaborations in various power engineering domains and across virtually all the continents. The collaborative efforts range from market mechanisms to renewable energy integration and from specific power topics to interdisciplinary projects.
IEEE Transactions on Circuits and Systems, 1976
The simulation of the transient response of a large interconnected power system involves the solu... more The simulation of the transient response of a large interconnected power system involves the solution of a very large system of differential-algebraic equations under a great variety of initial conditions and disturbances. The demands imposed on a digital transient stability program to i) study larger power system interconnections, ii) provide a more detailed representation of the power system components, and iii) permit the simulation of longer time periods, have the effect of increasing the computing time. The importance of, and the need for, efficient computational schemes is apparent. The method presented in this paper makes detailed use of the structural properties of the differential-algebraic system representation. The nonlinear differential-algebraic system is split into a nonstiff part with long time constants coupled to a stiff part with a sparse Jacobian matrix whose longest time constant is shorter than that of the first part. These two parts are linear in their respecti...
Urbana, Ill. : University of Illinois, Department of Electrical and Computer Engineering,, 2007
2004 was an active year for the PAP and the highlights are covered in this report. We acknowledge... more 2004 was an active year for the PAP and the highlights are covered in this report. We acknowledge the valuable support of the Affiliates and are most thankful to these companies for their continued support.
2020 IEEE Energy Conversion Congress and Exposition (ECCE), 2020
Harvesting offshore wind energy conventionally relies on multi-megawatt direct-drive permanent-ma... more Harvesting offshore wind energy conventionally relies on multi-megawatt direct-drive permanent-magnet synchronous generators equipped with full-power-rated active rectifiers. Functional integration of the generator and rectifier has led to the creation of an integrated generator-rectifier system with higher efficiency, reliability and power density. In this architecture, power electronics weight and efficiency depend on the generator inductance, while at the same time, the generator design must be optimized for weight and efficiency to realize the potential system-level benefits. This paper proposes a framework using the generator per-unit reactance as a handshake variable to co-design the generator and power electronics. The design approach enables the reduction of the system weight and conversion losses by 25% and 61%, respectively, for a 10-MW system. Using conservative assumptions, economic and reliability assessments show a 4.5% increase in annual energy production, a 9x reduction in long-term failure rate, and a 6.5% decrease in levelized cost of electricity.
2020 IEEE Energy Conversion Congress and Exposition (ECCE), 2020
Harvesting offshore wind energy conventionally relies on multi-megawatt direct-drive permanent-ma... more Harvesting offshore wind energy conventionally relies on multi-megawatt direct-drive permanent-magnet synchronous generators equipped with full-power-rated active rectifiers. Functional integration of the generator and rectifier has led to the creation of an integrated generator-rectifier system with higher efficiency, reliability and power density. In this architecture, power electronics weight and efficiency depend on the generator inductance, while at the same time, the generator design must be optimized for weight and efficiency to realize the potential system-level benefits. This paper proposes a framework using the generator per-unit reactance as a handshake variable to co-design the generator and power electronics. The design approach enables the reduction of the system weight and conversion losses by 25% and 61%, respectively, for a 10-MW system. Using conservative assumptions, economic and reliability assessments show a 4.5% increase in annual energy production, a 9x reduction in long-term failure rate, and a 6.5% decrease in levelized cost of electricity.
conducting research on challenges facing the electric power industry and educating the next gener... more conducting research on challenges facing the electric power industry and educating the next generation of power engineers. More information about PSERC can be found at the
Proceedings of the Annual Hawaii International Conference on System Sciences, 2020
2001 was an active year for the PAP and the highlights are covered in this report. We acknowledge... more 2001 was an active year for the PAP and the highlights are covered in this report. We acknowledge the valuable support of the Affiliates and are most thankful to these companies for their continued support.
IEEE Transactions on Power Systems, 2016
The deeper penetration of distributed energy resources (DERs) in microgrids (s) has led to their ... more The deeper penetration of distributed energy resources (DERs) in microgrids (s) has led to their wider deployment in specific applications. The inherent variability in loads and in renewable energy resource outputs necessitates the development and implementation of effective voltage control strategies so as to reliably serve the loads, particularly under islanded operations mode. We propose a dispersed control strategy to maintain voltage levels within the operational limits by means of the DERs reactive and active power outputs. We implement an optimization approach and demonstrate the effectiveness and the robustness of the proposed voltage control scheme using a set of representative studies from the extensive testing of the simulation approach performed with the methodology. Simulation results demonstrate the absence of any opportunity cost to implement the control action and the maximization of active power production by renewable energy resources.
Proceedings of the 41st Annual Hawaii International Conference on System Sciences (HICSS 2008), 2008
In the competitive electricity structure, demand response programs enable customers to react dyna... more In the competitive electricity structure, demand response programs enable customers to react dynamically to changes in electricity prices. The implementation of such programs may reduce energy costs and increase reliability. To fully harness such benefits, existing load controllers and appliances need around-theclock price information. Advances in the development and deployment of Advanced Meter Infrastructures (AMIs), Building Automation Systems (BASs), and various dedicated embedded control systems provide the capability to effectively address this requirement. In this paper we introduce a Meter Gateway Architecture (MGA) to serve as a foundation for integrated control of loads by energy aggregators, facility hubs, and intelligent appliances. We discuss the requirements that motivate the architecture, describe its design, and illustrate its application to a small system with an intelligent appliance and a legacy appliance using a prototype implementation of an intelligent hub for the MGA and ZigBee wireless communications.
Proceedings of the Thirtieth Hawaii International Conference on System Sciences
This paper describes a Web-based simulator of the Federal Energy Regulatory Commission (FERC) man... more This paper describes a Web-based simulator of the Federal Energy Regulatory Commission (FERC) mandated Open Access Same-Time Information System (OASIS) network. The purpose of the simulator is to provide a tool for study of the various aspects of an OASIS network and to gain a strong intuitive feel for its operations. For a specified simulation period, the OASISNET simulator reproduces an OASIS network of multiple nodes using the same communications medium as the actual system, the Internet, and with multiple players using the simulator simultaneously. Salient features of the simulator are its modular architecture, the ability to simulate multi-node OASIS network operations and to accept simultaneous access from remote users through use of client/server technology. The simulation focuses on the dissemination and use of the available transmission capability information. Sample applications of the new simulator are discussed.
Modeling dispatch constraints in production cost simulations based on the equivalent load method
IEEE Transactions on Power Systems, 1994
This paper presents a new rigorous and efficient algorithm to model a very general class of dispa... more This paper presents a new rigorous and efficient algorithm to model a very general class of dispatch constraints in production cost simulations based on the equivalent load method. The facet algorithm is based upon two observations: the equivalent load production cost calculation is a linear program, which can incorporate dispatch constraints as additional linear inequalities; it has a special structure
2005 was an active year for the PAP and the highlights are covered in this report. We acknowledge... more 2005 was an active year for the PAP and the highlights are covered in this report. We acknowledge the valuable support of the Affiliates and are most thankful to these companies for their continued support.
This project envisions a fundamental shift in the approach to the electric power infrastructure w... more This project envisions a fundamental shift in the approach to the electric power infrastructure with both a broadening of the electric grid to consider overall end energy use and a "flattening" of the control structure at all levels of the power grid the traditional control strategies. In particular, the research of the Northeastern/Tufts team concentrates on wide-area monitoring and estimation techniques for geographically-distributed electric power systems, with a special focus on mitigating the adverse effects of communication delay and information packet loss, adaptive power-flow control, and fault location from synchronized wide-area measurements. Coordination across wide areas is critical to ensuring that the future grid can enable efficient, low cost and reliable integration of renewables. As such, the work is a system development investigating several areas of control and communications, device technologies as well as electricity market structures. Commonalities arising across these diverse research tasks include the importance of new measurement technologies, increased functionality at the device level and managing uncertainty in both control systems and markets. More specifically, new phasor measurements are used in this work to enable wide area control of the power grid and understand system limits more precisely. Synchronized measurements are used also to locate short circuit faults occurring in the system. New power electronic functionality, both at the source and load, allow improved stability and voltage control. These functions will allow alternative sources to provide grid services to offset their higher costs. Managing uncertainty in the networked estimation and control systems, as for example we do with our delay mitigation scheme, improves reliability and thus, allows greater penetration of renewables. There has been continued rapid growth in renewable interconnections to the grid and the need for improved controls has become critical. These interconnections also necessitated novel ways of protection against system faults given the possibility of reverse flows on certain lines. This third year report details continued progress in understanding the fundamental controls, monitoring and communication structure needed to enable the needed wide area protection and control.
This project envisions a fundamental shift in the approach to the electric power infrastructure w... more This project envisions a fundamental shift in the approach to the electric power infrastructure with both a broadening of the electric grid to consider overall end energy use and a "flattening" of the control structure at all levels of the power grid the traditional control strategies. In particular, the research of the Northeastern/Tufts team concentrates on wide-area monitoring and estimation techniques for geographically-distributed electric power systems, with a special focus on mitigating the adverse effects of communication delay and information packet loss, adaptive power-flow control, and fault location from synchronized wide-area measurements. Coordination across wide areas is critical to ensuring that the future grid can enable efficient, low cost and reliable integration of renewables. As such, the work is a system development investigating several areas of control and communications, device technologies as well as electricity market structures. Commonalities arising across these diverse research tasks include the importance of new measurement technologies, increased functionality at the device level and managing uncertainty in both control systems and markets. More specifically, new phasor measurements are used in this work to enable wide area control of the power grid and understand system limits more precisely. Synchronized measurements are used also to locate short circuit faults occurring in the system. New power electronic functionality, both at the source and load, allow improved stability and voltage control. These functions will allow alternative sources to provide grid services to offset their higher costs. Managing uncertainty in the networked estimation and control systems, as for example we do with our delay mitigation scheme, improves reliability and thus, allows greater penetration of renewables. There has been continued rapid growth in renewable interconnections to the grid and the need for improved controls has become critical. These interconnections also necessitated novel ways of protection against system faults given the possibility of reverse flows on certain lines. This third year report details continued progress in understanding the fundamental controls, monitoring and communication structure needed to enable the needed wide area protection and control.
IEEE Power Engineering Society. 1999 Winter Meeting (Cat. No.99CH36233), 1999
We formulate a general framework of a competitive electricity generation supply market (CEM), emb... more We formulate a general framework of a competitive electricity generation supply market (CEM), embodying the salient attributes of the Poolco concept. This framework serves two principal purposes: to solve the selection by the CEM operator of the winners in a sealed bid auction for the right to serve load in each period of the auction horizon; and, to determine the profitmaximizing strategic bids of a generation supplier. The formulation represents the physical and operating considerations of the electric generation system, the multi-period nature of the auction as well as the market economics. The resulting large-scale nonlinear programming model has a structure that is effectively exploited for solution by Lagrangian relaxation. Under conditions of a perfectly competitive market, the strategic bids of a player can be derived analytically. Numerical results illustrate the effectiveness of the strategic bids. Directions for future research are discussed.
Transmission Planning
United States Government. The views and opinions of authors expressed herein do not necessarily s... more United States Government. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by its trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. Transmission System Operation and Interconnection
– We present an incentive scheme to stimulate investment in the improvement/expansion of the tran... more – We present an incentive scheme to stimulate investment in the improvement/expansion of the transmis-sion network in the competitive market environment. The formulation of these incentives is based on a decentralized transmission asset investment model and is derived from the value added to the social welfare by an asset invest-ment. In the formulation, we view each potential investor as a player in a cooperative game and we use the unique solution provided by the Shapley value to allocate the payment to each successful investor commensurated with the increase in social welfare the investment brings to the system. The formulation brings valuable insights on the transmission investment topic. We apply the proposed methodology to the Garver 6-bus system to illustrate the capabilites and flexibility of the scheme and to gain in-sights into the development of network improvements through the formulation proposed.
Under normal operating conditions, induction motors perform at levels below their optimum efficie... more Under normal operating conditions, induction motors perform at levels below their optimum efficiency. A control loop that includes a power electronics circuit drive and the induction motor can be developed to reduce power losses in the motor. By measuring the instantaneous power and voltage/frequency characteristics of the motor, a converter can be used to internally adjust the optimum voltage/frequency ratio. This ratio is defined as the ratio that uses minimum power for desired torques and speeds. The control loop will allow the converter to continuously monitor and adjust the motor's characteristics around an optimal operating point. Research will include theory, design, and implementation of the control technique mentioned above.
International Journal of Electrical Power & Energy Systems, 1991
In the competitive environment in which US utilities operate, auctions are becoming an accepted m... more In the competitive environment in which US utilities operate, auctions are becoming an accepted means .[or procuring resources to meet utilities 'projected needs. The rationale/'or instituting auctions is to effectively harness the competitive forces in electricity resource markets in order to implement least-cost planning objectives. PG&E, in cooperation with the other Cal(fornia investor-owned utilities. Southern Cal(/brnia Edison and San Diego Gas and Eh, ctric, has developed a muhi-attribute auction ./i'amework /or the procurement o/./hture resources. The Ji'amework uses the attributes o['capacity and energy price, dispatehability, location, start date flexibilio', price tfiversity, pro/ect viability and environmental impacts to evaluate customer benefits. This allows comparability between and trade~ff~s" among attributes. Other ke)' features include the use q/ multiple scenarios to explieitO' account ./i~r ./uel price and load growth uncertainty, the explicit evaluation qf long-term impacts and dynamic operating benefits q/'dispatchability, and the use ~['port/blio theory ./or the evaluation Of price diversity. The.bidding evaluation also uses optimal power flow derived loss adjustment .factors and incremental network reinlorcement costs and takes into account uncertainty in determining start-date flexibility. The ./i'amework is sz{~'eiently general to be usab[e not only Jm" auctions, but also.[or utility evaluation of maintenance, power contracts and other investment decisions. This paper describes the ./kamework and its implementation into a PC spreddsheet so/'tware package.
2006 IEEE Power Engineering Society General Meeting, 2006
The panel chair George Gross and the seven panelists from different parts of the world aim to sum... more The panel chair George Gross and the seven panelists from different parts of the world aim to summarize the key aspects of research collaborations in various power engineering domains and across virtually all the continents. The collaborative efforts range from market mechanisms to renewable energy integration and from specific power topics to interdisciplinary projects.
IEEE Transactions on Circuits and Systems, 1976
The simulation of the transient response of a large interconnected power system involves the solu... more The simulation of the transient response of a large interconnected power system involves the solution of a very large system of differential-algebraic equations under a great variety of initial conditions and disturbances. The demands imposed on a digital transient stability program to i) study larger power system interconnections, ii) provide a more detailed representation of the power system components, and iii) permit the simulation of longer time periods, have the effect of increasing the computing time. The importance of, and the need for, efficient computational schemes is apparent. The method presented in this paper makes detailed use of the structural properties of the differential-algebraic system representation. The nonlinear differential-algebraic system is split into a nonstiff part with long time constants coupled to a stiff part with a sparse Jacobian matrix whose longest time constant is shorter than that of the first part. These two parts are linear in their respecti...
Urbana, Ill. : University of Illinois, Department of Electrical and Computer Engineering,, 2007
2004 was an active year for the PAP and the highlights are covered in this report. We acknowledge... more 2004 was an active year for the PAP and the highlights are covered in this report. We acknowledge the valuable support of the Affiliates and are most thankful to these companies for their continued support.
2020 IEEE Energy Conversion Congress and Exposition (ECCE), 2020
Harvesting offshore wind energy conventionally relies on multi-megawatt direct-drive permanent-ma... more Harvesting offshore wind energy conventionally relies on multi-megawatt direct-drive permanent-magnet synchronous generators equipped with full-power-rated active rectifiers. Functional integration of the generator and rectifier has led to the creation of an integrated generator-rectifier system with higher efficiency, reliability and power density. In this architecture, power electronics weight and efficiency depend on the generator inductance, while at the same time, the generator design must be optimized for weight and efficiency to realize the potential system-level benefits. This paper proposes a framework using the generator per-unit reactance as a handshake variable to co-design the generator and power electronics. The design approach enables the reduction of the system weight and conversion losses by 25% and 61%, respectively, for a 10-MW system. Using conservative assumptions, economic and reliability assessments show a 4.5% increase in annual energy production, a 9x reduction in long-term failure rate, and a 6.5% decrease in levelized cost of electricity.
2020 IEEE Energy Conversion Congress and Exposition (ECCE), 2020
Harvesting offshore wind energy conventionally relies on multi-megawatt direct-drive permanent-ma... more Harvesting offshore wind energy conventionally relies on multi-megawatt direct-drive permanent-magnet synchronous generators equipped with full-power-rated active rectifiers. Functional integration of the generator and rectifier has led to the creation of an integrated generator-rectifier system with higher efficiency, reliability and power density. In this architecture, power electronics weight and efficiency depend on the generator inductance, while at the same time, the generator design must be optimized for weight and efficiency to realize the potential system-level benefits. This paper proposes a framework using the generator per-unit reactance as a handshake variable to co-design the generator and power electronics. The design approach enables the reduction of the system weight and conversion losses by 25% and 61%, respectively, for a 10-MW system. Using conservative assumptions, economic and reliability assessments show a 4.5% increase in annual energy production, a 9x reduction in long-term failure rate, and a 6.5% decrease in levelized cost of electricity.
conducting research on challenges facing the electric power industry and educating the next gener... more conducting research on challenges facing the electric power industry and educating the next generation of power engineers. More information about PSERC can be found at the
Proceedings of the Annual Hawaii International Conference on System Sciences, 2020
2001 was an active year for the PAP and the highlights are covered in this report. We acknowledge... more 2001 was an active year for the PAP and the highlights are covered in this report. We acknowledge the valuable support of the Affiliates and are most thankful to these companies for their continued support.
IEEE Transactions on Power Systems, 2016
The deeper penetration of distributed energy resources (DERs) in microgrids (s) has led to their ... more The deeper penetration of distributed energy resources (DERs) in microgrids (s) has led to their wider deployment in specific applications. The inherent variability in loads and in renewable energy resource outputs necessitates the development and implementation of effective voltage control strategies so as to reliably serve the loads, particularly under islanded operations mode. We propose a dispersed control strategy to maintain voltage levels within the operational limits by means of the DERs reactive and active power outputs. We implement an optimization approach and demonstrate the effectiveness and the robustness of the proposed voltage control scheme using a set of representative studies from the extensive testing of the simulation approach performed with the methodology. Simulation results demonstrate the absence of any opportunity cost to implement the control action and the maximization of active power production by renewable energy resources.
Proceedings of the 41st Annual Hawaii International Conference on System Sciences (HICSS 2008), 2008
In the competitive electricity structure, demand response programs enable customers to react dyna... more In the competitive electricity structure, demand response programs enable customers to react dynamically to changes in electricity prices. The implementation of such programs may reduce energy costs and increase reliability. To fully harness such benefits, existing load controllers and appliances need around-theclock price information. Advances in the development and deployment of Advanced Meter Infrastructures (AMIs), Building Automation Systems (BASs), and various dedicated embedded control systems provide the capability to effectively address this requirement. In this paper we introduce a Meter Gateway Architecture (MGA) to serve as a foundation for integrated control of loads by energy aggregators, facility hubs, and intelligent appliances. We discuss the requirements that motivate the architecture, describe its design, and illustrate its application to a small system with an intelligent appliance and a legacy appliance using a prototype implementation of an intelligent hub for the MGA and ZigBee wireless communications.
Proceedings of the Thirtieth Hawaii International Conference on System Sciences
This paper describes a Web-based simulator of the Federal Energy Regulatory Commission (FERC) man... more This paper describes a Web-based simulator of the Federal Energy Regulatory Commission (FERC) mandated Open Access Same-Time Information System (OASIS) network. The purpose of the simulator is to provide a tool for study of the various aspects of an OASIS network and to gain a strong intuitive feel for its operations. For a specified simulation period, the OASISNET simulator reproduces an OASIS network of multiple nodes using the same communications medium as the actual system, the Internet, and with multiple players using the simulator simultaneously. Salient features of the simulator are its modular architecture, the ability to simulate multi-node OASIS network operations and to accept simultaneous access from remote users through use of client/server technology. The simulation focuses on the dissemination and use of the available transmission capability information. Sample applications of the new simulator are discussed.
Modeling dispatch constraints in production cost simulations based on the equivalent load method
IEEE Transactions on Power Systems, 1994
This paper presents a new rigorous and efficient algorithm to model a very general class of dispa... more This paper presents a new rigorous and efficient algorithm to model a very general class of dispatch constraints in production cost simulations based on the equivalent load method. The facet algorithm is based upon two observations: the equivalent load production cost calculation is a linear program, which can incorporate dispatch constraints as additional linear inequalities; it has a special structure
2005 was an active year for the PAP and the highlights are covered in this report. We acknowledge... more 2005 was an active year for the PAP and the highlights are covered in this report. We acknowledge the valuable support of the Affiliates and are most thankful to these companies for their continued support.
This project envisions a fundamental shift in the approach to the electric power infrastructure w... more This project envisions a fundamental shift in the approach to the electric power infrastructure with both a broadening of the electric grid to consider overall end energy use and a "flattening" of the control structure at all levels of the power grid the traditional control strategies. In particular, the research of the Northeastern/Tufts team concentrates on wide-area monitoring and estimation techniques for geographically-distributed electric power systems, with a special focus on mitigating the adverse effects of communication delay and information packet loss, adaptive power-flow control, and fault location from synchronized wide-area measurements. Coordination across wide areas is critical to ensuring that the future grid can enable efficient, low cost and reliable integration of renewables. As such, the work is a system development investigating several areas of control and communications, device technologies as well as electricity market structures. Commonalities arising across these diverse research tasks include the importance of new measurement technologies, increased functionality at the device level and managing uncertainty in both control systems and markets. More specifically, new phasor measurements are used in this work to enable wide area control of the power grid and understand system limits more precisely. Synchronized measurements are used also to locate short circuit faults occurring in the system. New power electronic functionality, both at the source and load, allow improved stability and voltage control. These functions will allow alternative sources to provide grid services to offset their higher costs. Managing uncertainty in the networked estimation and control systems, as for example we do with our delay mitigation scheme, improves reliability and thus, allows greater penetration of renewables. There has been continued rapid growth in renewable interconnections to the grid and the need for improved controls has become critical. These interconnections also necessitated novel ways of protection against system faults given the possibility of reverse flows on certain lines. This third year report details continued progress in understanding the fundamental controls, monitoring and communication structure needed to enable the needed wide area protection and control.
This project envisions a fundamental shift in the approach to the electric power infrastructure w... more This project envisions a fundamental shift in the approach to the electric power infrastructure with both a broadening of the electric grid to consider overall end energy use and a "flattening" of the control structure at all levels of the power grid the traditional control strategies. In particular, the research of the Northeastern/Tufts team concentrates on wide-area monitoring and estimation techniques for geographically-distributed electric power systems, with a special focus on mitigating the adverse effects of communication delay and information packet loss, adaptive power-flow control, and fault location from synchronized wide-area measurements. Coordination across wide areas is critical to ensuring that the future grid can enable efficient, low cost and reliable integration of renewables. As such, the work is a system development investigating several areas of control and communications, device technologies as well as electricity market structures. Commonalities arising across these diverse research tasks include the importance of new measurement technologies, increased functionality at the device level and managing uncertainty in both control systems and markets. More specifically, new phasor measurements are used in this work to enable wide area control of the power grid and understand system limits more precisely. Synchronized measurements are used also to locate short circuit faults occurring in the system. New power electronic functionality, both at the source and load, allow improved stability and voltage control. These functions will allow alternative sources to provide grid services to offset their higher costs. Managing uncertainty in the networked estimation and control systems, as for example we do with our delay mitigation scheme, improves reliability and thus, allows greater penetration of renewables. There has been continued rapid growth in renewable interconnections to the grid and the need for improved controls has become critical. These interconnections also necessitated novel ways of protection against system faults given the possibility of reverse flows on certain lines. This third year report details continued progress in understanding the fundamental controls, monitoring and communication structure needed to enable the needed wide area protection and control.
IEEE Power Engineering Society. 1999 Winter Meeting (Cat. No.99CH36233), 1999
We formulate a general framework of a competitive electricity generation supply market (CEM), emb... more We formulate a general framework of a competitive electricity generation supply market (CEM), embodying the salient attributes of the Poolco concept. This framework serves two principal purposes: to solve the selection by the CEM operator of the winners in a sealed bid auction for the right to serve load in each period of the auction horizon; and, to determine the profitmaximizing strategic bids of a generation supplier. The formulation represents the physical and operating considerations of the electric generation system, the multi-period nature of the auction as well as the market economics. The resulting large-scale nonlinear programming model has a structure that is effectively exploited for solution by Lagrangian relaxation. Under conditions of a perfectly competitive market, the strategic bids of a player can be derived analytically. Numerical results illustrate the effectiveness of the strategic bids. Directions for future research are discussed.
Transmission Planning
United States Government. The views and opinions of authors expressed herein do not necessarily s... more United States Government. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by its trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. Transmission System Operation and Interconnection
– We present an incentive scheme to stimulate investment in the improvement/expansion of the tran... more – We present an incentive scheme to stimulate investment in the improvement/expansion of the transmis-sion network in the competitive market environment. The formulation of these incentives is based on a decentralized transmission asset investment model and is derived from the value added to the social welfare by an asset invest-ment. In the formulation, we view each potential investor as a player in a cooperative game and we use the unique solution provided by the Shapley value to allocate the payment to each successful investor commensurated with the increase in social welfare the investment brings to the system. The formulation brings valuable insights on the transmission investment topic. We apply the proposed methodology to the Garver 6-bus system to illustrate the capabilites and flexibility of the scheme and to gain in-sights into the development of network improvements through the formulation proposed.
Under normal operating conditions, induction motors perform at levels below their optimum efficie... more Under normal operating conditions, induction motors perform at levels below their optimum efficiency. A control loop that includes a power electronics circuit drive and the induction motor can be developed to reduce power losses in the motor. By measuring the instantaneous power and voltage/frequency characteristics of the motor, a converter can be used to internally adjust the optimum voltage/frequency ratio. This ratio is defined as the ratio that uses minimum power for desired torques and speeds. The control loop will allow the converter to continuously monitor and adjust the motor's characteristics around an optimal operating point. Research will include theory, design, and implementation of the control technique mentioned above.