Passive Islanding Detection Technique for Integrated Distributed Generation at Zero Power Balanced Islanding

Renewable power generation systems have more advantages in the integrated power system compared to the generation due to fossil fuels because of their advantages like reliability and power quality. One of the important problems due to such renewable distributed generation (DG) system is an unintentional islanding. Islanding is caused if DG supplies power to load after disconnecting from the grid. As per the DG interconnection standards, it is required to detect the islanding within two seconds after islanding with the equipments connected to it. In this paper a new passive islanding detection method is presented for wind DG integrated power system with rate of change of positive sequence voltage (ROCOPSV) and rate of change of positive sequence current (ROCOPSC). The islanding is detected if both the values of ROCOPSV and ROCONSV are more than a predefined threshold value. The test system results carried on MATLAB shows the performance of the proposed method for various islanding and non islanding events with different power imbalances. The results conclude that, this method can detect islanding even at balanced islanding with zero non detection zone (NDZ)

A Passive Islanding Detection Method for Neutral point clamped Multilevel Inverter based Distributed Generation using Rate of Change of Frequency Analysis

Presently renewable energies have taken a special place in the world and most of the Distributed Generations (DGs) used in the interconnected power system are utilized, renewable energy resources. Due to the DG’s advantages, including use of renewable energy such as, clean nature, does not pollute environment and having endless nature the use of these renewable resources to produce electrical energy in the world are increasing in day to day life. One problem with such Distributed generators is an unintentional islanding phenomenon. Islanding occurs when a Distributed Generation continues to energize an isolated part of a power system even after it was disconnected from the main grid, which is surrounded by unpowered lines. Since islanding can cause hazardous conditions for people and equipment which is connected to it. As per IEEE 1547 DG Interconnection standards, islanding should be quickly detected within 2 seconds, by protective relays and inverters that are part of the DG system. In this paper, a new passive method to identify islanding states has been proposed, based on the rate of change of frequency analysis (ROCOF) for a multilevel inverter based solar distributed generation systems. This method is efficient for both connecting DGs to the network with or without the Inverter. This method is more efficient than the existing methods and reducing the Non Detection Zone (NDZ), which is the disadvantage of existing passive methods and also clearly differentiating between the Islanding and Non-islanding events. The simulation results, which are carried on the MATLAB/Simulink environment shows the performance of the proposed method

PHARMACEUTICAL STANDARDIZATION OF SHATPALA GANDHAKA CHURNA

Rasa oushadis are the potent Ayurvedic preparations mainly containing metals and minerals. These Oushadis possess wide range of therapeutic efficacy and are considered superior because of their qualities like small dose, quick action, palatability and longer shelf life. Shatpala Gandhaka churna is an important Rasa oushadi described in Vaidya chintamani- Kushtha prakaranam indicated for all types of Kushtha, Grahani, Gulma, Mandagni. Shatpala Gandhaka Churna contains Shuddha Gandhaka, Shuddha Bhallataka, Shuddha Chitrakamula twak, Triphala, Vidanga, Trikatu, Trijataka, Chanaka, and Jeeraka. The main pharmaceutical procedures adopted in this study are Shodhana, Churna nirmana and preparation of capsule of Shatpala Gandhaka Churna. The specific pharmaceutical blend of these contents can result in a more effective formulation. Till now, no research work has been carried out to standardize this formulation. Therefore the present study has been planned to standardize the method of preparation of Shatpala Gandhaka churna according to the method explained in the classical literature.           

Determinants of Private Savings Effect on Economic Growth in Ethiopia

Private saving is a very important factor in bringing economic development, its working or efficiency is determined by different socio economic and political factors. In Ethiopia, private saving does not have a deep-rooted history because of frequent policy changes following the changes of government. The objective of this paper is to analyse the determinants of private saving in Ethiopia and also to check the long run or short run impact of real per capita GDP, real deposit interest rate, age dependency ratio, inflation rate and number of bank branches on private savings using time series annual data from 1978 to 2018. The research methodology employed are tests such as testing for stationery (unit root test) and co-integration test, rank of co-integration determined by using ARDL (Autoregressive- Distributed Lag) to characterize long-run and the short-run relationship between private saving and independent variables.  The model is estimated by using Ordinary Least Square (OLS) and/or E-Views 10 also offered a specialized estimator for handling ARDL model. The estimated results revealed that real per capita GDP, real deposit interest rate, age dependency ratio and number of bank branches have found to be statistically significant and positive effect (but real per capita GDP negative in the short run) on private savings while inflation rate is found non-significant and negative effect on private savings in Ethiopia both in the long and short run periods in the study period. Based on the result, the researcher concluded that level of real per capita GDP and number of bank branches is found to be important variable and have very significant impact on private savings. Finally, the study recommended that the national level policy makers or decision makers has to take measure to improve income levels of society and special attention to increases financial access throughout the country by further expanding bank branches or other financial institutions  and their services to increase private savings. Keywords: Determinants of private savings, Economic growth, ARDL, co-integration, Ethiopia DOI: 10.7176/JPID/60-01 Publication date:July 31st 202

Structural and Magnetic Hysteresis Properties of Co-Zr Substituted Hexagonal Barium Ferrites

Co-Zr substituted M-type hexagonal barium ferrites, with chemical formula BaCoxZrxFe12-2xO19 (where x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0), have been synthesized by double sintering ceramic method. The crystallographic properties, grain morphology and magnetic properties of these ferrites have been investigated by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM). The XRD patterns confirm the single phase with hexagonal structure of prepared ferrites. The magnetic properties have been investigated as a function of Co and Zr ion composition at an applied field in the range of 20 KOe. These studies indicate that the saturation magnetization (Ms) in the samples increases initially up to the Co-Zr composition of x=0.6 and decreases thereafter. On the other hand, the coercivity (Hc) and Remanent magnetization (Mr) are found to decrease continuously with increasing Co-Zr content. This property is most useful in permanent magnetic recording. The observed results are explained on the basis of site occupation of Co and Zr ions in the samples

Investigation and Analysis of Space Vector Modulation with Matrix Converter Determined Based on Fuzzy C-Means Tuned Modulation Indexs

Matrix converter performs energy conversion by directly connecting input phases with output phases through bidirectional switches. Conventional power converters make use of bulky reactive elements which are subjected to ageing, reduce the system reliability. The matrix converter (MC) stands as an alternative to conventional power converter. Furthermore MC’s provide bidirectional power flow nearly sinusoidal input and sinusoidal output waveform and controllable input power factor. In this work, three modulation methods have been simulated using MATLAB and compared on the basis of input current harmonics, output voltage harmonics and number of switching per cycle.  The three techniques simulated are, Optimal Venturini method, Direct Space Vector Modulation (DSVM) and Indirect Space Vector Modulation (ISVM) on Conventional Matrix Converter (CMC) and obtained form Fuzzy c-Means (FCM).  DSVM with FCM is proposed for obtainting best results compared to other three techniques

Finding Mobile Applications in Cellular Device-to-Device Communications: Hash Function and Bloom Filter-Based Approach

The rapid growth of mobile computing technology and wireless communication have significantly increased the mobile users worldwide. We propose a code-based discovery protocol for cellular device-to-device (D2D) communications. To realize proximity based services such as mobile social networks and mobile marketing using D2D communications, each device should first discover nearby devices, which have mobile applications of interest, by using a discovery protocol. The proposed discovery protocol makes use of a short discovery code that contains compressed information of mobile applications in a device. A discovery code is generated by using either a hash function or a Bloom filter. When a device receives a discovery code broadcast by another device, the device can approximately find out the mobile applications in the other device. The proposed protocol is capable of quickly discovering massive number of devices while consuming a relatively small amount of radio resources. We analyze the performance of the proposed protocol under the random direction mobility model and a real mobility trace. By simulations, we show that the analytical results well match the simulation results and that the proposed protocol greatly outperforms a simple non-filtering protoco

IDENTIFICATION OF POTENTIAL INHIBITORS FOR LOWERING CHOLESTEROL LEVEL BY INHIBITING PCSK9

ABSTRACTObjective: PCSK9 has medical significance in lowering cholesterol levels. Inhibitors target and inactivate PCSK9 in the liver. Knocking out PCSK9 (proprotein convertase subtilisin kexin 9) reduces the amount of harmful LDL cholesterol circulating in the bloodstream. There are two known inhibitors for treating the cardiovascular disease Arilocumab†and Evalocumabâ€. However there are many side-effects. The current study is to identify natural and synthetic inhibitor using the pharmacophoric feature of the known inhibitor and validating the short listed candidates using Molecular dynamics and ADMET properties.Methods: Known inhibitors for the PCSK9 Protein were taken from the BINDING DATABASE. Molecular docking was performed for the known inhibitors with the PCSK9 protein. After docking the best inhibitor was selected and the docking result was then imported to find the pharmacophoric features.Results: The pharmacophore model was generated with 3 features containing  1 hydrogen bond acceptor(A),1 Hydrogen bond donor(B) and 1 Aromatic ring. The constructed e-pharmacophore model was screened with more than 20000 natural compounds. 5 compounds were short listed. Among them ZINC85625485 has  glide  score  of  -13.03  kcal/mol  with  glide  energy  was  -57.62 kcal/mol and ZINC85625406 has glide score of -8.1kcal/mol with glide energy was -39.33kcal/mol were taken as the best Hits.Conclusion: PCSK9 is known to be a therapeutic agent as it controls the plasma LDL cholesterol levels by posttranslational regulation of the LDL receptor. Therefore, up-regulation of PCSk9 can lead to elevated cholesterol level in such case inhibition of PCSK9 will be a effective remedy. In this study already known inhibitors were taken and pharmacophore feature was generated. Zinc database was screened to find out novel compounds with similar pharmacophore features that can act as potentially active compound against PCSK9. ZINC85625485 and ZINC85625406 were short listed as lead compounds with Molecular dynamics simulation and checking the ADMET properties. Keywords: PCSK9, Docking, ADMET, Molecular Dynamics.                                                            Â

Simulation of High Step-Up Resonant Parallel LC Converter for Grid Connected Renewable Energy Sources

With the rapid improvement of large-scale renewable energy sources and HVDC grid, it is a capable alternative to connect the renewable energy sources to the HVDC grid with a pure dc system, in which high-power high-voltage step-up dc–dc converters are the key equipment to transmit the electrical energy. This paper presents a High step up LC converter it can achieve high voltage gain using an LC parallel resonant tank.Also provided zero voltage switching (ZVS) technology under switch turn-On condition also at turn-Off conditions at main power switches by rectifying diodes to reduce the conduction losses. The operation principle of the converter and its resonant parameter selection is presented in this paper. The operation principle of the converter has been successfully verified with the help of MATLAB/SIMULINK