Showing papers by "K. Shanti Swarup published in 2015"

Estimation of Electronic Suppression Circuit Resistance for Protective Relaying Applications

Abstract: The transient response of instrument transformers affects the performance of high-speed relays, particularly speed and overreach in case of distance protection. Transient response of a capacitive voltage transformer depends on the type of ferro-resonance suppression circuit (FSC), i.e., active, passive, or electronic, provided in the secondary to damp the ferro-resonant oscillations. The objective of this article is not to estimate optimum resistance but to provide a systematic approach instead of the trial-and-error approach to estimate damping resistance for the electronic ferro-resonance suppression circuit used in the: capacitive voltage transformer for protective relaying application. The performance of the numerical distance relay for the: capacitive voltage transformer with estimated damping resistance in the electronic ferro- resonance suppression circuit is tested and validated in real time using a field programmable gate array.

Transient modeling and control of DFIG for grid power leveling during variable wind speed

Abstract: This paper presents the modeling and control of grid connected wind driven doubly fed induction generator (DFIG). Mathematical model of induction machine is developed in stator flux oriented dq frame which makes possible independent control of active and reactive powers. The power injected to the grid from the DFIG system is maintained constant irrespective of the wind speed with the help of active source in the DFIG system. A Battery Energy Storage System (BESS) is connected at the dc link to provide the active power support. Super synchronous and sub synchronous modes are simulated to verify the bidirectional power flow nature of back to back converter. The power fed from rotor side and stator side are analyzed during different modes of operation.

Residential Energy Consumption Scheduling Techniques Under Smart Grid Environment

Abstract: In recent years the load demand by residential consumers are rapidly increasing due to the usage of many electric appliances in daily needs. Load demand during peak hours is becoming increasingly larger than off-peak hours, which is the major reason for inefficiency in generation capacity. Introduction of smart grid technology in Demand Side Management programs provides an alternative to installation of new generation units. Consumers can play a major role in reducing their energy consumption by communicating with utilities so that they can minimize their energy costs and get incentives, which also helps utilities in many ways. Smart grid technologies provide opportunities to employ different pricing schemes which also help in increasing the efficiency of appliance scheduling techniques. Optimal energy consumption scheduling reduces the peak load demand in peak hour. Peak average ratio (PAR) also minimizes the energy consumption cost. In this paper, we observes different energy consumption scheduling techniques that schedule the house hold appliances in real-time to achieve minimum energy consumption cost and to reduce peak load demand in peak hours to shape the peak load demand. Formulation and Solution methodology of residential energy consumption scheduling is presented with simulation results illustrating the working of the model.

A novel optimal controller design for doubly fed induction generator speed control

Abstract: This paper presents a new method for doubly fed induction generator performance optimization using electromagnetic transient simulation (EMTP) program. A 2 MW doubly fed induction generator(DFIG) is modeled in electromagnetic transient simulation PSCAD/EMTDC. To optimize the performance of DFIG, each controller parameters like kp and k should be properly tuned and cordinated. The objective function (OF) is formed in terms of design parameters like kp and k of the controller to reduce the error arise due to overshoot, steady state error etc. The nonlinear optimization program evaluates the parameter values to minimize the OF value in successive iterations. In this paper, the OF is formed to minimize the error in outer speed control loop of rotor side converter of DFIG.

Restoration of smart distribution grid using self healing characteristics in multi agent environment

Abstract: Power system restoration in smart distribution network with distributed computing resources are evaluated in this paper. The issues in distribution network restoration in a centralized environment are discussed and how the distributed computing can help elevate these condition are tested in this work. Network reconfiguration is attempted to reduce the duration of loss of load in a self healing environment. This will help in restore the system fast without human intervention providing maximum utilization of resources while reducing customer dissatisfaction.