National Institute of Technology, Meghalaya

About: National Institute of Technology, Meghalaya is a education organization based out in Shillong, India. It is known for research contribution in the topics: Control theory & Computer science. The organization has 503 authors who have published 1062 publications receiving 6818 citations. The organization is also known as: NIT Meghalaya & NITM.

Measurement Technique for Ideal Selection of Sensors and Accurate Force Recovery on Aerodynamic Models

Abstract: The accuracy of force measurement and prediction is of prime importance in the calibration of a force balance in aerodynamic models. Multi-point calibration has recently been introduced which has proven to be a more accurate prediction technique than the traditional single-point calibration technique. This paper describes the multi-point calibration of a double cone model using tri-axial and uniaxial accelerometers to obtain the maximum number of responses with accurate prediction using a minimum number of accelerometers. The multi-point calibration was performed by applying forces at nine locations on a double cone model considering two configurations. Firstly, accelerations were measured simultaneously using one tri-axial and two uniaxial accelerometers which were fixed at three locations of the model-balance assembly. Secondly, forces were measured from the responses obtained simultaneously using one uniaxial and one triaxial accelerometer fixed at two locations of the model-balance assembly. The prediction of the forces was performed using Adaptive Neuro Fuzzy Inference System (ANFIS). Genetic algorithm was used to obtain pure normal and pure axial forces from the components of applied forces at different calibration locations. The forces were predicted accurately from the responses measured using two accelerometers (one uniaxial and one triaxial accelerometer) as well as from the responses of three accelerometers (one tri-axial and two uniaxial accelerometers). Thus, tri-axial accelerometers can be used rather than using multiple numbers of uniaxial accelerometers. The use of tri-axial accelerometers leads to the ease of experimentation as mounting of multiple number of uniaxial accelerometers makes the calibration set-up complex and response measurement challenging. The attainment of responses in three directions at a single location is possible only using tri-axial accelerometer which helps in understanding the actual degrees of freedom experienced by the model. Thus, the use of tri-axial accelerometers for obtaining the responses in dynamic calibration is a better alternative than using uniaxial accelerometers.

Optimal Cluster Count and Coverage Analysis in a Gaussian Distributed WSNs Using TESM

Abstract: In wireless sensor network, node deployment can be established as a Gaussian or a uniform distribution. Gaussian distribution provides a reduction in energy hole problem and is preferable to realistic applications like intrusion detection. This paper proposed the cluster size optimization for the Gaussian distributed sensor network where the base station (BS) follows a Tunable Elfes sensing model (TESM), and the mode of communication between node is considered to be of single-hop and multi-hop. Further, we derived the analytical expression of finding the optimal number of clusters. After analyzing the simulation result, it is noted that multi-hop communication model consumes less energy. Also, in this paper, the effect of using Tunable Elfes sensing model (TESM) on coverage is quantitatively analyzed. It is observed that the coverage fraction decreases significantly with an increase in the separation between the nodes.

SPC based approach for Frequency Control of Power Systems Penetrated with Fast Acting Reserve

Abstract: Continuous replacement of the synchronous units by converter interfaced generators (CIGs) in the smart electrical grid would reduce the rotational inertia and inevitably jeopardizes the frequency stability. A low inertia electric grid is less competent of withstanding the frequency excursions during any abnormal conditions. Therefore, in this work, phase-locked loop less synchronous power controller (SPC) approach is incorporated in the power electronic converters for emulating inertia virtually. Besides provision of the short term inertial support, present work also designed a frequency regulation strategy that utilizes fast acting reserves (FAR) such as demand response and energy storage. FAR unit is basically a CIGs which is controlled or re-dispatch using load-generation imbalance signal obtained from online monitoring system rather than frequency measurement. Critical investigations reveal that the coordinated operation of SPC based HVDC links and FAR exceptionally reduce the peak deviations and the oscillations in the tie power and frequency response.