Engineering Commons^™

Continuous Monitoring Of Neutral Grounding Resistors And Reactors, Rahim Jafari

Electronic Thesis and Dissertation Repository

Electrical power system components are designed three-phase balanced and symmetric with the internal connection of wye or delta. The common point of the wye-connected equipment, which is called neutral, is impedance grounded for many reasons such as fault ride through by controlling transient overvoltages, and limiting the ground overcurrents. Depending on the application, different neutral impedance grounding methods exist that employ resistors or reactors with/without neutral grounding transformers. These apparatuses are known as Neutral Grounding Devices (NGD). The most well-known sort of NGDsarethe Neutral Grounding Resistor (NGR) and Neutral Grounding Reactor (NGL) which are the main focus of this research …

Spectral And Energy Efficient Communication Systems And Networks, Abdulbaset Hamed

Electronic Thesis and Dissertation Repository

In this thesis, design and analysis of energy- and spectral-efficient communication and cellular systems in micro wave and millimeter wave bands are considered using the following system performance metrics: i) Energy efficiency; ii) Spectral efficiency; iii) Spatial spectral efficiency; iv) Spatial energy efficiency, and v) Bit error rate. Statistical channel distributions, Nakagami-m and Generalized-K, and path loss models, Line of Sight (LOS) and Non-Line of Sight (NLOS), are used to represent the propagation environment in these systems. Adaptive M-QAM and M-CPFSK communication systems are proposed to enhance their efficiency metrics as a function of Signal-to-Noise Ratio (SNR) over the channel. …

Non-Pilot Protection Of The Inverter-Dominated Ac Microgrid, Houman Lahiji

Electronic Thesis and Dissertation Repository

The main objective of this research is to develop reliable non-pilot protection and control strategies for the inverter-dominated microgrid. First, an improved Proportional-Derivative (PD) droop control strategy is proposed for enhanced disturbance response of the inverter-dominated AC microgrid. The proposed strategy significantly improves microgrid dynamic response and stability without requiring communication between distributed energy resources. Moreover, the impacts of large startup currents of induction motors on the stability and power quality of the inverter-dominated microgrid are investigates and recommendations for minimizing the associated adverse effects are made.

Subsequently, a fast, selective, and reliable protection strategy for the inverter-dominated microgrid is …

New Algorithms For Locating Faults In Series Capacitive Compensated Transmission Lines, Tirath Bains

Electronic Thesis and Dissertation Repository

The precise location of the fault in a series capacitive compensated transmission line (SCCTL) plays an integral part in limiting the maintenance time following its tripping due to the occurrence of a permanent fault. Since, an SCCTL acts as a huge corridor of power, its outage will result in huge monetary losses which are directly proportion to the time it remains out of service. In worst case scenario, the tripping of an SCCTL might lead to the cascaded tripping of the parallel transmission lines due to overloading. Therefore, the need for an accurate and robust fault location algorithm for the …

Transformerless High-Power Medium-Voltage Multi-Module Pv Converters, Hasan Bayat

Electronic Thesis and Dissertation Repository

This thesis is focused on the modular multilevel converter (MMC) for Photovoltaic (PV) applications. It is an attempt to address the issues associated with the modeling, control, and power mismatch elimination of the MMC-based PV systems. Firstly, a new real power reference generation scheme is proposed that creates a linear relationship between the real power reference of the system and the dc link voltage of the submodules. Further, a new power mismatch elimination strategy is proposed for the MMC-based PV system which ensures balanced currents are delivered to the host grid regardless of leg and arm power mismatches. The thesis …

A High Gain Dc-Dc Full-Bridge Converter, Prashanth Prabhu

Electronic Thesis and Dissertation Repository

High gain DC-DC converters have become increasingly popular in recent years as there is greater need to interface low voltage DC sources such as solar cells and batteries with much higher voltage DC buses. A new high gain DC-DC converter with high gain, galvanic isolation and an integrated passive snubber network is proposed in the thesis. In the thesis, the general operation of the converter is discussed, its modes of operation are explained and its features are reviewed. The design of the converter is then discussed and a set of general guidelines that can be used in the design are …