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Abstract: Power system state estimation with exclusive utilization of synchronous phasor measurements demands that the system should be completely observable through PMUs only. To have minimum number of PMUs, the PMU placement issue in any network is an optimization problem. A three stage optimal PMU placement method is presented in this paper using network connectivity information. The method initially considers PMU in all buses of the network. Stage I and Stage II of the algorithm iteratively determine (i) less important bus locations from where PMUs are eliminated and (ii) strategically important bus locations where PMUs are retained. Stage III of the algorithm further minimizes the number of PMU using pruning operation. The set of PMUs obtained after Stage III is an optimal set of PMU locations for network observability. Proposed method is further extended for assuring complete observability under single PMU outage cases. Simulation results for IEEE 14-bus, 24-bus, 30-bus, 57-bus, 118-bus and New England 39-bus test systems are presented and compared with the existing techniques. Results show that the proposed method is simple to implement and accurate compared to other existing methods. [Copyright &y& Elsevier]

Abstract: This paper presents an efficient and realistic contingency analysis method. The contingencies are ranked based on their risk index value which incorporates both the probability and the severity of the contingency. Severity for each contingency is computed based on load loss, equipment overloads, voltage magnitude violation at nodes and system frequency deviation from the nominal value. The proposed method considers line/transformer outages as well as generator outage contingencies. A modified Fast Decoupled Power Flow method which considers frequency and voltage dependent characteristic of loads, generator regulation characteristics and sensitivity based transformer tap adjustments is used to evaluate the contingencies. The power flow method is suitable for any AC/DC power system and can carry out contingency analysis even if the system gets islanded. [Copyright &y& Elsevier]

This paper describes a restoration guidance simulator, which allows power system operator/planner to simulate and plan restoration events in an interactive mode. The simulator provides a list of restoration events according to the priority based on some restoration rules and list of priority loads. It also provides in an interactive mode the list of events, which becomes possible as the system grows during restoration. Further, the selected event is validated through a load flow and other analytical tools to show the consequences of implementing the planned event. [Copyright &y& Elsevier]

Presents an algorithm for dynamic state estimation of power systems. Attempt to model dynamics of power system into the state estimation process; Short-Term Load Forecasting (STLF) as one of the application areas of the Artificial Neural Network (ANN); Dependence of bus voltage variations on load changes.

Highlights: [•] A new method to maximize the profit of a micro grid connected hybrid power system is proposed. [•] The hybrid power system has a role to play in maintaining the micro grid frequency. [•] Excess energy interchange between grid and hybrid system is charged under frequency based pricing. [•] The problem is formulated as dynamic optimization problem and is solved using ABC algorithm. [•] Results demonstrate the strategies of the hybrid system to operate its PSH plant for system economy. [ABSTRACT FROM AUTHOR]

Faults on EHV lines are quite common. They cause disruption in power supply. Accurate location of faults will result in faster maintenance and restoration of supply. This paper presents a new method for the location of faults based on wavelet multiresolution analysis (MRA). EMTP (Microtran) is employed to generate the time domain input signal. Daubechies eight (D-8) wavelet transforms of the three phase currents on transmission lines from both the ends are used. The effects of fault inception angle and fault impedance are examined. Extensive simulation work has been carried out and results indicate that the proposed method is very effective in locating the fault with a high accuracy. [Copyright &y& Elsevier]