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Item ANALYSIS OF KATHMANDU GRID DIVISION AND INTREGATED NEPAL POWER SYSTEM WITH OPTIMAL PLACEMENT AND SIZING OF CAPACITOR(Pulchowk Campus, 2021-03) THAKURI, MANISHA SHAHIThe lower voltage of transmission system in the Integrated National Power System (INPS) has been a major concern for the Nepal Electricity Authority (NEA). The lower transmission voltage induces the lower voltage in the sub-coordinates (sub-transmission and distribution system) causing reduced voltage and overall higher system loss. The loss in the transmission system has increased from 4.35% to 4.51% in previous year. A total of 97.5km 132kV line and 182km of 220kV line in the FY2076/77 along with 72.5 MVAR of capacitor bank has been augmented in last couple of years. Though such appreciable effort, considering the system enhancement, has been done in the improvement of the transmission system, the problem is still existing. The main reasons for the existing problem can be: the higher increase in demand than the supporting infrastructures. So, this research aims to study the existing system during the system peak and perform an impact analysis in the system with the addition of the optimum sized capacitors in the optimum location for the voltage improvement and overall loss reduction. The study also emphasizes the economic aspect with the addition of the capacitors analyzing the various economic parameters. The sub-objective of the study also includes analysis of the loading status of the transmission lines in the Kathmandu valley. For the acknowledgement of system, the Electrical Transient Analyzer Program (ETAP) has been used as simulation tool. Adaptive Newton-Raphson has been used for the load flow and the Optimum Capacitor Placement (OCP) module inbuilt with Genetic Algorithm (GA) to determine the optimum placement and sizing of the capacitor banks. Moreover, a techno-economic analysis has been performed for the determination of the most suitable voltage level for the capacitor placement. From the analysis it has been found that the system suffers a transmission line loss of 4.16% in the system peak. Also, 6 optimum substations with the total reactive power of 80 MVAR needs to be added in the system for the energy savings of about 16.02 GWh per annum. The economic analysis shows that the implementation of the study has an is economically sustainable with the payback period of 5.97 years and 19.69 % Internal Rate of Return when the capacitors are placed at the most financially suitable voltage level i.e., 11kV determined from the results obtained.Item OPTIMAL ALLOCATION OF CAPACITORS AND DGS FOR TECHNO-ECONOMIC BENEFITS IN RADIAL DISTRIBUTION SYSTEM(Pulchowk Campus, 2021-02) BASTOLA, SARUPower loss minimization and voltage stability improvement are important areas of power systems due to existing transmission line contingency, financial loss of utility and power system blackouts. Optimal allocation (i.e. siting and sizing) of Distributed Generation (DG) and Optimal Capacitor Placement are the best ways to strengthen the efficiency of power system. In the present work, a Evaporation-rate based water cycle algorithm has been taken into account to allocate capacitor banks and DGs along the radial distribution network. The objective function is adopted to minify the system power loss, to improve the system voltage profile and finally to carry out for power loss reduction with economic point of view. Firstly, capacitor placement is applied to standard IEEE buses. In the next stage, Distributed Generations is incorporated in the standard IEEE buses, thirdly capacitor and DGs with unity pf are incorporated simultaneously in the IEEE bus system and finally capacitor and DGs with controllable pf are incorporated simultaneously in the IEEE bus system. Finally, practical distribution feeder (i.e., New Chabahil Feeder and Daachhi Feeder) of Kathmandu valley will be taken to apply the theoretically proven technique to reduce voltage drop and power loss. The overall accuracy and reliability of the approach has been validated and tested on radial distribution systems with differing topologies and of varying sizes and complexities. The results shown by the proposed approach have been found to outperform the results of existing heuristic algorithms found in the literature for the given problem. The test was performed for four cases. Case I: placement of capacitors only, Case II: Placement of DG only, case III: Placement of DG (unity pf) and capacitors simultaneously, Case IV: Placement of DG (with controllable pf) and capacitors simultaneously taking into consideration for technical objectives only, Case V: Placement of DG (with controllable pf) and capacitors simultaneously taking into consideration for techno-economic objectives. The power loss found with my thesis work is lower than that of with the methodologies in the reference paper. For IEEE 33 bus system, power loss in case I, case II, case III, case IV, and case V was 34.79%, 62.10, 90.23%, 92.04%, and 63.67 % of the base case respectively. Similarly, for IEEE 69 bus system, power loss in case I, case II, case III, case IV, and case V were 35.34%, 69.14%, 94.36%, 96.24%, and 35.53% of the base case respectively the power loss. Moreover, the results for the practical systems (Daachhi feeder and New Chabahil feeder) are supposed to have considerable upgradation in the Nepalese distribution system in the future for lower power loss and better voltage profile. For Daachhi Feeder, power loss in case I, case II, case III, case IV, and case V was 50.25%, 48.52%, 96.10%, 96.77%, and 70.95% of the base case respectively. Similarly, for New-Chabahil Feeder, power loss in case I, case II, case III, case IV, and case V were 37.46%, 63.54%, 97.10%, 98.23%, and 54% of the base case respectively the power lossItem Optimal Placement of Phasor Measurement Unit on Integrated Nepal Power System Ensuring Power System Observability(Pulchowk Campus, 2021-09) Rimal, BishalFor better state estimation of power system, phasor measurement unit (PMU) are superior to supervisory control and data acquisition system. Optimal PMU placement is the strategic placement of a minimum number of PMUs to ensure power system observability. Optimal PMU placement is essential to overcome the economic burden during the deployment of PMU on every bus. A strategy integrated with a modified Simulated Annealing algorithm is proposed in this thesis with the consideration of the effect of a radial bus during optimal PMU placement problems. In addition to the normal case, cases for single PMU outage and zero injection bus have been implemented in MATLAB. The simulation result of the proposed modified simulated annealing algorithm is compared and validated with modified simulated annealing algorithm for IEEE 14-bus, 30-bus, 57-bus, and 118-bus system. To recognize the superior placement set from diverse solutions given by meta-heuristic algorithm, placement set with least number of PMU and higher system observability redundancy index is used. The proposed strategy on modified Simulated Annealing algorithm has improved the result in terms of an optimal number of PMU, probability of finding an optimal number of PMU, and system observability redundancy index. For normal case, the number of PMUs required for complete power system observability of 90 bus Integrated Nepal Power System is found to be 28. Similarly, with the consideration of single PMU outage and zero injection bus, the number of PMU required is found to be 62 and 26 respectively.Item Scenario Analysis of Integrated Nepal Power System for Energy Banking between Nepal & India from Nepalese Perspective for Projected Ten Years(Pulchowk Campus, 2021-02) Puri, BijayThe surplus – deficit energy analysis for projected ten years of Integrated Nepal Power System (INPS) gives ideas about the monthly energy status in different scenarios and helps in better planning for Energy Banking between Nepal and India from Nepalese perspective and also in increasing the opportunities of internal consumption within the country. Energy banking between power systems of Nepal and India will enhance the power system security and reliability of Nepal power system. The real problems created by delays in commissioning of upcoming generation projects due to different delaying factors such as delays in commissioning of projects from their PPA concluded date and delays in completion of transmission projects will change the pattern and amount of generations in upcoming periods which results into difficulty in planning purpose. Similarly, the increase in both the generations and expected energy consumption also impacts the INPS in future as well. This thesis presents the scenario analysis of surplus – deficit energy for projected ten years period with the consideration of different scenarios in both the generation and consumption sector and simulates the load flow analysis of planned INPS after the saturation of new generation projects for fiscal year 084/85 in most likely generation scenario i.e. Shift IPP and NEA Plants scenario. Three scenarios viz. commissioning of upcoming projects in accordance with the Power Purchase Agreement (PPA) concluded date, with one year delay for projects coming under Independent Power Producers (IPPs) & additional three years delay in projects coming under Nepal Electricity Authority (NEA) and its sister organization are considered in generation sectors. The consumption sector is introduced with five scenarios viz. Normal, Growth with Categorization of Consumption, Intervention with Induction Chulo, Intervention with Electric Vehicle and Combined Intervention of Induction Chulo and Electric Vehicle. Surplus – Deficit (S – D) ratio has been used for studying the relative dominance of surplus or deficit energy over a year. For the projected ten years period, the surplus – deficit energy of each month of those fiscal years are determined. This study clearly decides for monthly energy banking scenario between two countries in both the normal load consumption growth in Nepal and also with opportunities of increasing use of electrical energy. This study also models and simulates the planned INPS after generation saturation in “Shift NEA and IPP Plants” scenario for five scenarios to predict the import export options in five energy consumption scenarios as well. iv When the energy demand is expected to grow at the rate of 8% per annum, the maximum export of energy has been observed for months of Ashoj. The study shows the Dhalkebar – Muzzafarupur 400 kV line has been fully used upto its capacity and around 2094 MW power export has been observed through 400 kV Butwal – Gorakhpur cross border transmission link. When the energy demand is expected to grow as per growth rate with categorization of consumption, the maximum import (in the month of Falgun) is achieved with four import lines viz. Dhalkebar – Muzzafarpur 400 kV line, Tanakpur – Mahendranagar 132 kV transmission line, Butwal – Gorakhpur 400 kV line and Kusaha – Katiya 132 kV line. Similarly, when the energy consumption policy is implemented as intervention with induction chulo or combined intervention of both induction chulo and electric vehicle for maximum import in these scenarios with monthly peak demands of about 5803MW and 6139 MW respectively for fiscal year 084/85, six import lines in accordance with cross – border planning have been neede to accommodate the total import peak demand within their loading capacity. These lines are Tanakpur – Mahendranagar 132 kV line, Butwal – Gorakhpur 400 kV line, Dhalkebar – Muzzafarpur 400 kV line, Kusaha – Kataiya 132 kV, Parwanipur – Raxaul 132 kV line and Duhabi – Purnea 400 kV lines. However, Amlekhgunj – Kamane – Pathlaiya – Parwanipur – Birgunj – Simara – Amlekhgunj loop is provided with additional capacitor banks to compensate for convergence problem cause by reactive power need in latter two import scenarios. When the export scenario is analyzed with electric vehicle integration policy in the months of Ashoj, only Dhalkebar – Muzzafarpur 400 kV line is needed to accommodate the export demand which is in the range of capacity of this line (i.e.1200 MW). The transformers of Balaju, Bhaktapur, Chapali, Dhalkebar, Hetauda, Suichatar, Khimti and Parwanipur grids is found critically overloaded in all scenarios and should be upgraded once the upcoming generation projects saturates in INPS. The 66 kV and 132 kV transmission lines of Kathmandu sub – system and Amlekhgunj – Kamane – Pathlaiya – Parwanipur – Birgunj – Simara – Amlekhgunj sub – sytem is found critically overloaded in all scenarios. Similarly, all the 66 kV and 132 kV in buses in INPS have been found to operate with critical bus voltages in all scenarios after generation saturation in planned INPS indicating vulnerability of our INPS as well.