European Journal of Advances in Engineering and Technology

80-90

Authors: Mohammad Arifuzzaman, Naheed NazneenTuli1, Yu Keping, Quang N Nguyen and Sato Takuro

In Information Centric Networking (ICN), on-path caching is an integrated caching solution with-in an Autono-mous System's (AS) local network. However, it is seen that in on-path caching, the content is cached en-route in the reverse path towards the Interest generator. Thus, local Rendezvous Network (RENE) /Name Resolution System (NRS) (in routing through name resolution) or FIB (in name-based routing) is not conscious of the cached data. Therefore, the most extensively deployed intra-domain routing protocol and their forwarding strategy is not capable of addressing all available temporary cached copies of the content. Hence, on-path caching strategy experiences two major downsides: numerous replicas of same content within AS without adding significant value in terms of cache resource utilization and an approach taken to minimize redundancy ends up with the cost of fetching more copy of similar content. In this paper, we introduce an integrated caching and forwarding solution which minimizes the caching redundancy and maximizes the probability of finding nearby cached content. We leverage Name Data Networking (NDN) node architecture and its forwarding plane/strategy (of routing) to attain our goal. Mathematical analysis to determine load balance and cache hit ratio, and simulation results considering average hop-distance and server hit ratio authenticate the efficiency of our proposed scheme.

99-105

Authors: Shailendra Shrivastava, Vishal Sharma and Dr. Annapurna Bhargava

In last few decades the demand of electricity grownup drastically. Due to higher demand and aging of networks it is indispensable to control the power flow in transmission systems. The flexible AC Transmission system (FACTS) provides effective control over one or more transmission system parameters to enhance controllability and increase power transfer capability. UPFC is one of the most powerful FACTS devices which can simultaneously control all the parameters of the system i.e., the line impedance, transmission angle and bus voltage. This paper presents a device called Distributed Power Flow Controller (DPFC) which is derived from the UPFC by eliminating common DC link. It is most recent and one of the ultimate device within the FACTS family. The DPFC has control capacities of all the parameters of the transmission network. With DPFC the active power exchange between the shunt and series converter is done through the transmission line by the 3rd harmonic current. It is designed with multiple single phase series converters (D-FACTS) and one three phase shunt converter. The DPFC has more control capability at much reduced cost and improves reliability. This work presents modelling of a damping controller based on ‘Generalized Theory of the Instantaneous Active and Reactive Power’ proposed by Akagi commonly known as P-Q theory, the simulation results demonstrate pa-rameters like, compensating current flowing through controllers, and active power flow.

113-117

Authors: S Saravanan and RS Dubey

We analytically explore the high optical performance of an ultrathin amorphous silicon (a-Si) solar cell by rigorous coupled wave analysis (RCWA) method. By studying the absorption spectrum and field intensity profiles, we have investigatedthe importance of the grating structure via scattering and diffraction mechanism. Asignificant improvement is observed with the cell efficiency(η) as high as ~19% and the current density (Jsc) about ~29.47mA/cm2 within 50nm thick a-Si absorber region for theperpendicular polarization case(TE). In addition, this optimal designis compared with the various solar cells based on thedifferentback reflector. The demonstrated design includesindium tin oxide (ITO) as a perfectanti-reflection coating (ARC) andgoodtransparent conducting oxide layer as well. Overall, an ultrathin a-Si solar cell based on dual grating structure could show enhanced optimal performance.

122-127

Authors: Meera R Karamta and J G Jamnani

Flexible AC Transmission System (FACTS) is a progressive technology that has allowed power system utilities to make the most out of the existing grid and control the governing parameters that affect the power flow and/or sta-bility of the transmission and power system broadly. One of the most important FACTS devices is Unified Power Flow Controller (UPFC) which provides fast-acting reactive power compensation on high-voltage electricity transmission networks. The aim of this paper is to discuss in detail the dynamic model of UPFC. It is integrated to a Single Machine Infinite Bus system (SMIB) for state estimation. Power system State Estimation is important for efficient control and operation the system. State Estimator is a computer program which processes the available measurements to obtain the best values of state variables. Conventional State Estimation is static in nature. Static state estimation takes system snap-shots and hence the dynamics of system are not captured efficiently. Thus Dy-namic State Estimation (DSE) is becoming more appropriate. It efficiently processes the data captured at smaller sampling time to obtain state vectors. Using the information about state vector at time instant k, a Dynamic State Estimator can predict the state vector at next time stamp k+1. In the present work, results for estimation of system dynamic states as well as UPFC dynamic states are presented using the Extended Kalman filter method.