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J Gurney - One of the best experts on this subject based on the ideXlab platform.
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Voltage Stability monitoring based on the concept of coupled single port circuit
Power and Energy Society General Meeting, 2012Co-Authors: Yunfei Wang, Ebrahim Vaahedi, Iraj Rahimi Pordanjani, Tongwen Chen, J GurneyAbstract:Summary form only given: This paper reveals that the impedance match (or the Thevenin circuit) based Voltage Stability monitoring techniques have problems to predict Voltage Stability limits when applied to multi-load power systems. Power system loads are nonlinear and dynamic. They cannot be simply represented as Thevenin circuit parameters for impedance match analysis. To overcome these difficulties, a new concept called “coupled single-port circuit” is proposed in this paper. The concept decouples a meshed network into individual single generator versus single bus network and, as a result, a modified version of the impedance match theorem can be used. This leads to a real-time Voltage Stability monitoring scheme without the need to estimate Thevenin parameters. The scheme can estimate Voltage Stability margin and identify weak areas in a system based on the SCADA and PMU data. Case studies conducted on several test systems have verified the validity of the proposed method.
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Voltage Stability monitoring based on the concept of coupled single port circuit
IEEE Transactions on Power Systems, 2011Co-Authors: Yunfei Wang, Ebrahim Vaahedi, Iraj Rahimi Pordanjani, Tongwen Chen, J GurneyAbstract:This paper reveals that the impedance match (or the Thevenin circuit) based Voltage Stability monitoring techniques have problems to predict Voltage Stability limits when applied to multi-load power systems. Power system loads are nonlinear and dynamic. They cannot be simply represented as Thevenin circuit parameters for impedance match analysis. To overcome these difficulties, a new concept called “coupled single-port circuit” is proposed in this paper. The concept decouples a meshed network into individual single generator versus single bus network and, as a result, a modified version of the impedance match theorem can be used. This leads to a real-time Voltage Stability monitoring scheme without the need to estimate Thevenin parameters. The scheme can estimate Voltage Stability margin and identify weak areas in a system based on the SCADA and PMU data. Case studies conducted on several test systems have verified the validity of the proposed method.
Iraj Rahimi Pordanjani - One of the best experts on this subject based on the ideXlab platform.
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Application of Channel Components Transform to design shunt reactive compensation for Voltage Stability improvement
International Journal of Electrical Power & Energy Systems, 2014Co-Authors: Iraj Rahimi Pordanjani, Wilsun XuAbstract:Abstract Channel Components Transform (CCT) is a network decoupling transform that has recently been proposed. The effective performance of CCT in Voltage Stability analysis and monitoring has been shown before. This paper extends the application of CCT to Voltage Stability enhancement. For this purpose, the CCT is used and a strategy for shunt compensation is proposed in order to improve the Voltage Stability of power systems. The proposed strategy is direct, effective and practical. The detail algorithms of the proposed strategy are presented in this paper. The strategy is also verified by case studies using standard test systems.
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Voltage Stability monitoring based on the concept of coupled single port circuit
Power and Energy Society General Meeting, 2012Co-Authors: Yunfei Wang, Ebrahim Vaahedi, Iraj Rahimi Pordanjani, Tongwen Chen, J GurneyAbstract:Summary form only given: This paper reveals that the impedance match (or the Thevenin circuit) based Voltage Stability monitoring techniques have problems to predict Voltage Stability limits when applied to multi-load power systems. Power system loads are nonlinear and dynamic. They cannot be simply represented as Thevenin circuit parameters for impedance match analysis. To overcome these difficulties, a new concept called “coupled single-port circuit” is proposed in this paper. The concept decouples a meshed network into individual single generator versus single bus network and, as a result, a modified version of the impedance match theorem can be used. This leads to a real-time Voltage Stability monitoring scheme without the need to estimate Thevenin parameters. The scheme can estimate Voltage Stability margin and identify weak areas in a system based on the SCADA and PMU data. Case studies conducted on several test systems have verified the validity of the proposed method.
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Voltage Stability monitoring based on the concept of coupled single port circuit
IEEE Transactions on Power Systems, 2011Co-Authors: Yunfei Wang, Ebrahim Vaahedi, Iraj Rahimi Pordanjani, Tongwen Chen, J GurneyAbstract:This paper reveals that the impedance match (or the Thevenin circuit) based Voltage Stability monitoring techniques have problems to predict Voltage Stability limits when applied to multi-load power systems. Power system loads are nonlinear and dynamic. They cannot be simply represented as Thevenin circuit parameters for impedance match analysis. To overcome these difficulties, a new concept called “coupled single-port circuit” is proposed in this paper. The concept decouples a meshed network into individual single generator versus single bus network and, as a result, a modified version of the impedance match theorem can be used. This leads to a real-time Voltage Stability monitoring scheme without the need to estimate Thevenin parameters. The scheme can estimate Voltage Stability margin and identify weak areas in a system based on the SCADA and PMU data. Case studies conducted on several test systems have verified the validity of the proposed method.
Ebrahim Vaahedi - One of the best experts on this subject based on the ideXlab platform.
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Voltage Stability monitoring based on the concept of coupled single port circuit
Power and Energy Society General Meeting, 2012Co-Authors: Yunfei Wang, Ebrahim Vaahedi, Iraj Rahimi Pordanjani, Tongwen Chen, J GurneyAbstract:Summary form only given: This paper reveals that the impedance match (or the Thevenin circuit) based Voltage Stability monitoring techniques have problems to predict Voltage Stability limits when applied to multi-load power systems. Power system loads are nonlinear and dynamic. They cannot be simply represented as Thevenin circuit parameters for impedance match analysis. To overcome these difficulties, a new concept called “coupled single-port circuit” is proposed in this paper. The concept decouples a meshed network into individual single generator versus single bus network and, as a result, a modified version of the impedance match theorem can be used. This leads to a real-time Voltage Stability monitoring scheme without the need to estimate Thevenin parameters. The scheme can estimate Voltage Stability margin and identify weak areas in a system based on the SCADA and PMU data. Case studies conducted on several test systems have verified the validity of the proposed method.
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Voltage Stability monitoring based on the concept of coupled single port circuit
IEEE Transactions on Power Systems, 2011Co-Authors: Yunfei Wang, Ebrahim Vaahedi, Iraj Rahimi Pordanjani, Tongwen Chen, J GurneyAbstract:This paper reveals that the impedance match (or the Thevenin circuit) based Voltage Stability monitoring techniques have problems to predict Voltage Stability limits when applied to multi-load power systems. Power system loads are nonlinear and dynamic. They cannot be simply represented as Thevenin circuit parameters for impedance match analysis. To overcome these difficulties, a new concept called “coupled single-port circuit” is proposed in this paper. The concept decouples a meshed network into individual single generator versus single bus network and, as a result, a modified version of the impedance match theorem can be used. This leads to a real-time Voltage Stability monitoring scheme without the need to estimate Thevenin parameters. The scheme can estimate Voltage Stability margin and identify weak areas in a system based on the SCADA and PMU data. Case studies conducted on several test systems have verified the validity of the proposed method.
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large scale Voltage Stability constrained optimal var planning and Voltage Stability applications using existing opf optimal var planning tools
IEEE Transactions on Power Systems, 1999Co-Authors: Ebrahim Vaahedi, J. Tamby, Y. Mansour, D. SunAbstract:Traditionally in optimal VAr planning, the feasible operation has been translated as observing Voltage profile criteria ensuring that the system Voltage profile is acceptable for system normal and post contingency conditions. This feasibility definition is not sufficient when considering the VAr planning practice of the utilities concerned with Voltage Stability problems. Presently, these utilities use two reinforcement criteria for VAr additions. While for VAr design in the regions the Voltage profile criteria is considered, for bulk transmission system VAr resources are designed to guard against Voltage inStability. This paper reports on the findings of a recently completed EPRI project evaluating the existing optimal VAr planning/OPF tools for Voltage Stability constrained VAr planning and Voltage Stability applications. Two of the selected tools were adapted to address these applications on four large scale utility systems (up to 6000 buses). The results were also verified using EPRI's Voltage Stability program (VSTAB). The results obtained indicate that OPF/VAr planning tools can be used to address Voltage Stability constrained VAr planning and Voltage Stability applications in an accurate way. Additional advantages offered by these tools are easier procedures, less computation and avoidance of engineering judgment in identifying the amount of VAr requirement at the candidate sites.
Yunfei Wang - One of the best experts on this subject based on the ideXlab platform.
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Voltage Stability monitoring based on the concept of coupled single port circuit
Power and Energy Society General Meeting, 2012Co-Authors: Yunfei Wang, Ebrahim Vaahedi, Iraj Rahimi Pordanjani, Tongwen Chen, J GurneyAbstract:Summary form only given: This paper reveals that the impedance match (or the Thevenin circuit) based Voltage Stability monitoring techniques have problems to predict Voltage Stability limits when applied to multi-load power systems. Power system loads are nonlinear and dynamic. They cannot be simply represented as Thevenin circuit parameters for impedance match analysis. To overcome these difficulties, a new concept called “coupled single-port circuit” is proposed in this paper. The concept decouples a meshed network into individual single generator versus single bus network and, as a result, a modified version of the impedance match theorem can be used. This leads to a real-time Voltage Stability monitoring scheme without the need to estimate Thevenin parameters. The scheme can estimate Voltage Stability margin and identify weak areas in a system based on the SCADA and PMU data. Case studies conducted on several test systems have verified the validity of the proposed method.
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Voltage Stability monitoring based on the concept of coupled single port circuit
IEEE Transactions on Power Systems, 2011Co-Authors: Yunfei Wang, Ebrahim Vaahedi, Iraj Rahimi Pordanjani, Tongwen Chen, J GurneyAbstract:This paper reveals that the impedance match (or the Thevenin circuit) based Voltage Stability monitoring techniques have problems to predict Voltage Stability limits when applied to multi-load power systems. Power system loads are nonlinear and dynamic. They cannot be simply represented as Thevenin circuit parameters for impedance match analysis. To overcome these difficulties, a new concept called “coupled single-port circuit” is proposed in this paper. The concept decouples a meshed network into individual single generator versus single bus network and, as a result, a modified version of the impedance match theorem can be used. This leads to a real-time Voltage Stability monitoring scheme without the need to estimate Thevenin parameters. The scheme can estimate Voltage Stability margin and identify weak areas in a system based on the SCADA and PMU data. Case studies conducted on several test systems have verified the validity of the proposed method.
David J Hill - One of the best experts on this subject based on the ideXlab platform.
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static Voltage Stability analysis of distribution systems based on network load admittance ratio
IEEE Transactions on Power Systems, 2019Co-Authors: Yue Song, David J Hill, Tao LiuAbstract:It is well known that a single (constant power) load infinite-bus system reaches a static Voltage Stability limit point, or equivalently, a singularity point of the power flow Jacobian, at the unity line-load admittance ratio, i.e., the equivalent admittance of the load has the same modulus as the transmission line admittance. In this paper, we rigorously extend this result to generic distribution systems with distributed generators (DGs). We introduce a new concept called the network-load admittance ratio that is in terms of the parameters of power network, loads, and DGs. This concept is a generalization of the line-load admittance ratio that characterizes the loading status of a distribution system with the effects of DGs included. We prove that the power flow Jacobian is singular if and only if the network-load admittance ratio is unity, which provides new insights into the mechanism of Voltage Stability. In addition, we establish a new Voltage Stability index by using the network-load admittance ratio. Numerical simulations on several IEEE test systems show that the index has good linearity with load increase and estimates Voltage Stability margin with high precision. The index also reflects the impact of DG penetration level and control mode on Voltage Stability. The obtained results can be extended to ZIP load models, unbalanced three-phase networks, and mesh networks with slight modifications.
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nonlinear dynamic load models with recovery for Voltage Stability studies
IEEE Transactions on Power Systems, 1993Co-Authors: David J HillAbstract:Motivated by projects in Sweden on Voltage Stability analysis and associated load modeling, a simple dynamic load model is proposed which captures the usual nonlinear steady-state behavior plus load recovery and overshoot. The parameters of the model can be related to physical devices depending on the time zone following a disturbance. A simple but important dynamic Voltage Stability analysis is developed based on the model. >
