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 & Electric power system. The organization has 503 authors who have published 1062 publications receiving 6818 citations. The organization is also known as: NIT Meghalaya & NITM.

Efficient Design of Quantum Circuits Using Nearest Neighbor Constraint in 3D Architecture

Abstract: Synthesis and optimization of quantum circuits have received significant attention from researchers in recent years. Developments in the physical realization of qubits in quantum computing have led...

A Real-Time Synchronized Harmonic Phasor Measurements-Based Fault Location Method for Transmission Lines

Abstract: In this paper, a real-time synchronized harmonic phasor measurements-based fault location (RT-SHPM-FL) method for transmission lines is proposed. At transmission line protection center (TPC), the synchronized harmonic phasor measurements are obtained from all phasor measurement units (PMU) deployed in a power system. At each bus, the PMU estimates time-tagged 100 and 150 Hz phasors of 3-ɸ current signals in addition to fundamental phasor (50 Hz). The proposed RT-SHPM-FL method detects and locates a fault using the magnitude of 100 and 150 Hz phasors of 3-ɸ currents and equivalent harmonic phasors (EHPs), respectively. These EHPs are calculated from the magnitude of time-tagged 50, 100 and 150 Hz three-phase current phasors. For estimating the fault distance, the RT-SHPM-FL method has employed support vector regression (SVR), because of its mimicking nature, generalization and robustness. The functioning of the proposed fault location method has been validated in real-time on a scaled-down laboratory model of 400 kV extra high voltage (EHV) transmission line of 400 km long. The experimental results and discussions show that the proposed method locates transmission line faults accurately. Further, a comparative study of the proposed fault location method using SVR and adaptive neuro-fuzzy inference system has revealed that the former one is more reliable in fault location than the latter one since the error is within ± 1%.

Implementation of Digital PWM on Buck-Type CSI Fed BLDC Motor Drive

Abstract: The unabating advancement in the field of permanent magnet brushless dc (BLDC)motor drive technology has made it more popular. Buck-type current source inverter has further found its place as the driver of BLDC motors due to its square-wave current injection and short-circuit tolerant essence. However, usage of the extra switch which is driven at a high frequency reduces the cost-effectiveness of the driver. Moreover, conventional pulse width modulation techniques that are implemented require a complex and costly circuits or processors. This also adds to the cost of the whole driving scheme. Due to the extra cost related to the driving scheme, BLDC motor still finds sparse applications in commercial usage. This paper has made an attempt to implement a buck-type current source inverter to drive a BLDC motor, and the control strategy is based on digital pulse width modulation. The simplicity of digital pulse width modulation makes it compatible to be implemented on a reduced cost application specific integrated circuit. The application of digital pulse width modulation and buck-type current source inverter leads to low frequency operation of all the switches present in the inverter which further minimizes the cost. With the usage of buck-type current source inverter the major snag of digital pulse width modulation that is speed stability is also addressed. The total control strategy and driving scheme is designed and verified using simulations.

Adaptive Control of the Wind Turbine Transmission System for Smooth Power Generation

Abstract: Wind energy sector is growing rapidly now a day’s as compared to other renewable sources of energy. The energy conversion from wind to electrical energy through hydrostatic transmission (HST) has been studied. The hydrostatic transmission system has been used for the power transfer from low-speed wind turbine rotor shaft to a high-speed generator shaft using variable displacement axial piston pump and motor. A fuzzy PID controller has been used to control the rotational speed of the pump and motor by controlling the displacement ratio. The hydraulic and overall efficiency has found to be approximately 82.2% and 38.8%, respectively. The performance of present dual control system has been found quite satisfactory as it is capable of maintaining output motor speed better compare to the single control mode. The constant output motor speed ensure quality power output in fluctuating wind speed and gusts.

A Study of Chemical Treatment of Natural Fibers and Its Effect on the Mechanical Properties of Developed Composites

Abstract: In this chapter, three different types of natural fibers namely jute, banana, and bamboo fibers were used as reinforcing material to fabricate the three different types of composite laminates. The composites were prepared by taking 50–60% weight fraction of the fiber. Two different types of chemical treatments of natural fibers were carried out to study the effect of chemical treatment of natural fibers on the mechanical properties (tensile and flexural) of the developed composites. The natural fibers were treated with (i) 5% of sodium hydroxide (NaOH) for 4 h and (ii) 5% NaOH for 4 h followed by 1% of potassium hydroxide (KOH) and 1% of hydrogen peroxide (H2O2) for 2 h. The mechanical properties such as (i) tensile strength, modulus, and percentage elongation and (ii) flexural strength, modulus, and percentage elongation of the developed composites were evaluated. The results indicate that natural fibers treated with 5% NaOH, 1% KOH, and 1% H2O2 resulted in better mechanical properties than the 5% NaOH treated natural fiber-based composites.