Hemanshu Pota - Academia.edu (original) (raw)
Papers by Hemanshu Pota
Robotics and Autonomous Systems, 2006
... Actually, it frequently occurs that Gless's function offers better results for stability... more ... Actually, it frequently occurs that Gless's function offers better results for stability judgment under a system disturbance such as faults on transmission lines. The other is to simplify determination of the desired coefficients. ... [P(x,x)]Tdx Jo = r [F(X))Tdx Jo (7) ...
2015 IEEE Power & Energy Society General Meeting, 2015
2012 IEEE International Power Engineering and Optimization Conference, 2012
ABSTRACT This paper proposes a distributed generator (DG) placement methodology based on newly de... more ABSTRACT This paper proposes a distributed generator (DG) placement methodology based on newly defined term reactive power loadability. The effectiveness of the proposed planning is carried out over a distribution test system representative of the Kumamoto area in Japan. Firstly, this paper provides simulation results showing the sensitivity of the location of renewable energy based DG on voltage profile and stability of the system. Then, a suitable location is identified for two principal types DG, i. e., wind and solar, separately to enhance the stability margin of the system. The analysis shows that the proposed approach can reduce the power loss of the system, which in turn, reduces the size of compensating devices.
ABSTRACT As existing distribution networks were designed to deliver unidirectional power to consu... more ABSTRACT As existing distribution networks were designed to deliver unidirectional power to consumers and require minimal control intervention, they result in largely passive infrastructures. The installation of distributed generation (DG) units with significant capacity in these passive networks can cause reverse power flows, which will result in some conflicts with the operation of the existing protection system. In this context, utilities around the world have started establishing requirements to ensure safe and reliable interconnection of generators in low- and medium-voltage networks. The technical grid code requirements and regulations vary considerably from country to country. However, any standard should address the critical need to make the DG marketable by providing uniform criteria and requirements relevant to the performance, operation, and safety. This paper presents a critical review of the requirements adopted by distribution companies in selected countries, such as the U.S., the U.K., Germany, and Australia, to facilitate the connection of DG. The main problems, such as voltage regulation, islanding operation, and dynamic interactions among DG and loads, are discussed to identify a few points where attention is still needed to improve the reliability of distribution systems.
European Journal of Control, 2013
2007 46th IEEE Conference on Decision and Control, 2007
2008 American Control Conference, 2008
2007 International Conference on Industrial and Information Systems, 2007
This paper presents a streamlined approach to future Precision Autonomous Farming (PAF). It focus... more This paper presents a streamlined approach to future Precision Autonomous Farming (PAF). It focuses on the preferred specification of the farming systems including the farming system layout, sensing systems and actuation units such as tractor-implement combinations. The authors propose the development of the Precision Farming Data Set (PFDS) which is formed off-line before the commencement of the crop cultivation and
Proceedings of the 38th IEEE Conference on Decision and Control (Cat. No.99CH36304), 1999
Abstract Proposes a special type of colocated feedback controllers for flexible structures. The c... more Abstract Proposes a special type of colocated feedback controllers for flexible structures. The controllers are a parallel combination of high-Q resonant circuits. Each resonant circuit is tuned to a pole (or the resonant frequency) of the flexible structure. Experimental results ...
2013 IEEE Grenoble Conference, 2013
ABSTRACT Traditional distribution networks were not originally designed to accommodate power gene... more ABSTRACT Traditional distribution networks were not originally designed to accommodate power generation facilities. The installation of distributed generation (DG) units with significant capacity in these passive networks can cause reverse power flows which will result in some conflicts with the operation of the existing protection system. In this context, utilities around the world have started establishing requirements to ensure safe and reliable interconnection of generators in low- and mediumvoltage networks. Grid interconnection is presently one of the most important issues involving DG. This paper presents a critical review of the requirements adopted by distribution companies in selected countries such as the USA, the UK, Germany and Australia to facilitate the connection of DG. Critical issues such as voltage regulation, islanding operation, dynamic interactions among DG and loads are discussed to identify a few points where attention is still needed to improve the reliability of distribution systems.
Journal of Intelligent & Robotic Systems, 2011
This paper presents a novel compensation method for the coupled fuselage-rotor mode of a Rotary w... more This paper presents a novel compensation method for the coupled fuselage-rotor mode of a Rotary wing Unmanned Aerial Vehicle (RUAV). The presence of stabilizer bar limits the performance of attitude control of an RUAV. In this paper, a positive position feedback (PPF) is introduced to increase the sta- bility margins and allow higher control bandwidth. The identified model is used
IEEE Transactions on Power Systems, 1989
IEEE Power and Energy Society General Meeting, USA 2012
This paper addresses the problem of designing an output feedback decentralized control of interco... more This paper addresses the problem of designing an output feedback decentralized control of intercon- nected power systems under large changes in real and reactive loads that cause large structural changes in the system model. The controller uses only the speed of the generator as its input. On load tap changers are also incorporated in the model and in the controller design. The design is carried out within a large-scale Markov jump parameter systems framework. This has allowed for a robust guaranteed performance con- troller to be designed. Simulations were carried out to eval uate the performance of the designed controller and to compare it with state feedback controllers.
ABSTRACT There are several advantages of using linear differential inclusions (LDIs) to describe ... more ABSTRACT There are several advantages of using linear differential inclusions (LDIs) to describe nonlinear systems and other types of complex systems (such as, systems with time-varying uncertainties and/or saturation). From the control point of view, for example, it may be easier to design a controller for a nonlinear system by using a linear description of it in the form of an LDI (instead of using the nonlinear equations for the same purpose). With this premise, we focus on modeling of a class of nonlinear systems via a norm-bounded LDI (NLDI) model. One of the main contributions of the proposed modeling approach is the use of the mean-value theorem to represent the nonlinear system by a linear parameter-varying (LPV) model, which is then mapped into a polytopic LDI (PLDI) within the region of interest. To avoid the combinatorial problem that is inherent of polytopic models for medium- and large-sized systems, the PLDI is transformed into an NLDI, and the whole process is carried out ensuring that all trajectories of the underlying nonlinear system are also trajectories of the resulting NLDI within the operating region of interest. Furthermore, it is also possible to choose a particular structure for the NLDI parameters to reduce the conservatism in the representation of the nonlinear system by the NLDI model, and this feature is also one of the main contributions of this paper. A numerical example is presented at the end of this paper to demonstrate the effectiveness of this approach.
Robotics and Autonomous Systems, 2006
... Actually, it frequently occurs that Gless's function offers better results for stability... more ... Actually, it frequently occurs that Gless's function offers better results for stability judgment under a system disturbance such as faults on transmission lines. The other is to simplify determination of the desired coefficients. ... [P(x,x)]Tdx Jo = r [F(X))Tdx Jo (7) ...
2015 IEEE Power & Energy Society General Meeting, 2015
2012 IEEE International Power Engineering and Optimization Conference, 2012
ABSTRACT This paper proposes a distributed generator (DG) placement methodology based on newly de... more ABSTRACT This paper proposes a distributed generator (DG) placement methodology based on newly defined term reactive power loadability. The effectiveness of the proposed planning is carried out over a distribution test system representative of the Kumamoto area in Japan. Firstly, this paper provides simulation results showing the sensitivity of the location of renewable energy based DG on voltage profile and stability of the system. Then, a suitable location is identified for two principal types DG, i. e., wind and solar, separately to enhance the stability margin of the system. The analysis shows that the proposed approach can reduce the power loss of the system, which in turn, reduces the size of compensating devices.
ABSTRACT As existing distribution networks were designed to deliver unidirectional power to consu... more ABSTRACT As existing distribution networks were designed to deliver unidirectional power to consumers and require minimal control intervention, they result in largely passive infrastructures. The installation of distributed generation (DG) units with significant capacity in these passive networks can cause reverse power flows, which will result in some conflicts with the operation of the existing protection system. In this context, utilities around the world have started establishing requirements to ensure safe and reliable interconnection of generators in low- and medium-voltage networks. The technical grid code requirements and regulations vary considerably from country to country. However, any standard should address the critical need to make the DG marketable by providing uniform criteria and requirements relevant to the performance, operation, and safety. This paper presents a critical review of the requirements adopted by distribution companies in selected countries, such as the U.S., the U.K., Germany, and Australia, to facilitate the connection of DG. The main problems, such as voltage regulation, islanding operation, and dynamic interactions among DG and loads, are discussed to identify a few points where attention is still needed to improve the reliability of distribution systems.
European Journal of Control, 2013
2007 46th IEEE Conference on Decision and Control, 2007
2008 American Control Conference, 2008
2007 International Conference on Industrial and Information Systems, 2007
This paper presents a streamlined approach to future Precision Autonomous Farming (PAF). It focus... more This paper presents a streamlined approach to future Precision Autonomous Farming (PAF). It focuses on the preferred specification of the farming systems including the farming system layout, sensing systems and actuation units such as tractor-implement combinations. The authors propose the development of the Precision Farming Data Set (PFDS) which is formed off-line before the commencement of the crop cultivation and
Proceedings of the 38th IEEE Conference on Decision and Control (Cat. No.99CH36304), 1999
Abstract Proposes a special type of colocated feedback controllers for flexible structures. The c... more Abstract Proposes a special type of colocated feedback controllers for flexible structures. The controllers are a parallel combination of high-Q resonant circuits. Each resonant circuit is tuned to a pole (or the resonant frequency) of the flexible structure. Experimental results ...
2013 IEEE Grenoble Conference, 2013
ABSTRACT Traditional distribution networks were not originally designed to accommodate power gene... more ABSTRACT Traditional distribution networks were not originally designed to accommodate power generation facilities. The installation of distributed generation (DG) units with significant capacity in these passive networks can cause reverse power flows which will result in some conflicts with the operation of the existing protection system. In this context, utilities around the world have started establishing requirements to ensure safe and reliable interconnection of generators in low- and mediumvoltage networks. Grid interconnection is presently one of the most important issues involving DG. This paper presents a critical review of the requirements adopted by distribution companies in selected countries such as the USA, the UK, Germany and Australia to facilitate the connection of DG. Critical issues such as voltage regulation, islanding operation, dynamic interactions among DG and loads are discussed to identify a few points where attention is still needed to improve the reliability of distribution systems.
Journal of Intelligent & Robotic Systems, 2011
This paper presents a novel compensation method for the coupled fuselage-rotor mode of a Rotary w... more This paper presents a novel compensation method for the coupled fuselage-rotor mode of a Rotary wing Unmanned Aerial Vehicle (RUAV). The presence of stabilizer bar limits the performance of attitude control of an RUAV. In this paper, a positive position feedback (PPF) is introduced to increase the sta- bility margins and allow higher control bandwidth. The identified model is used
IEEE Transactions on Power Systems, 1989
IEEE Power and Energy Society General Meeting, USA 2012
This paper addresses the problem of designing an output feedback decentralized control of interco... more This paper addresses the problem of designing an output feedback decentralized control of intercon- nected power systems under large changes in real and reactive loads that cause large structural changes in the system model. The controller uses only the speed of the generator as its input. On load tap changers are also incorporated in the model and in the controller design. The design is carried out within a large-scale Markov jump parameter systems framework. This has allowed for a robust guaranteed performance con- troller to be designed. Simulations were carried out to eval uate the performance of the designed controller and to compare it with state feedback controllers.
ABSTRACT There are several advantages of using linear differential inclusions (LDIs) to describe ... more ABSTRACT There are several advantages of using linear differential inclusions (LDIs) to describe nonlinear systems and other types of complex systems (such as, systems with time-varying uncertainties and/or saturation). From the control point of view, for example, it may be easier to design a controller for a nonlinear system by using a linear description of it in the form of an LDI (instead of using the nonlinear equations for the same purpose). With this premise, we focus on modeling of a class of nonlinear systems via a norm-bounded LDI (NLDI) model. One of the main contributions of the proposed modeling approach is the use of the mean-value theorem to represent the nonlinear system by a linear parameter-varying (LPV) model, which is then mapped into a polytopic LDI (PLDI) within the region of interest. To avoid the combinatorial problem that is inherent of polytopic models for medium- and large-sized systems, the PLDI is transformed into an NLDI, and the whole process is carried out ensuring that all trajectories of the underlying nonlinear system are also trajectories of the resulting NLDI within the operating region of interest. Furthermore, it is also possible to choose a particular structure for the NLDI parameters to reduce the conservatism in the representation of the nonlinear system by the NLDI model, and this feature is also one of the main contributions of this paper. A numerical example is presented at the end of this paper to demonstrate the effectiveness of this approach.