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The communication schemes have rapidly changed the face of the human means of communication. The evolution from one generation to another has triggered many challenges on the design methodologies of RF designers. As the evolution ensued, the spectrally efficient modulation schemes have resulted in the substantial rise of PAPR, the peak-to-average power ratio. To enable the efficient amplification of the high PAPR signals, this thesis explores the areas of Load modulated Balanced amplifiers that can be inherently reconfigured to achieve a better efficiency than the conventional RF power amplifiers that see a significant drop in the efficiency as the signal is backed-off from the maximum power level. In the communication environment, the load mismatch to the power amplifier does result in the degraded efficiency profile which is detrimental to the performance of the communication system. Hence, the power amplifier stage needs to be mismatch resilient. A three mode reconfigurable balanced power amplifier that can tolerate the mismatch due to the antenna array in massive MIMO is presented. The transistor's analog-digital duality is exploited for deploying it as an amplifier and a switch in the designed amplifier stage to enable the reconfiguration between the respective modes of operation. In addition, the output matching topology is designed to be symmetric for the corresponding amplifier stages with an input branch-line quadrature coupler and a unique harmonic tuning methodology that is used to effectively achieve a higher order load modulation in one of the modes, HLMBA. The other two modes of the PA stage are mismatch resilient and their performance is also observed to be efficient with switch settings dedicated to offer mismatch resilience at varied terminations.

Power system is vulnerable to disastrous climate events due to sequential or successive equipment failure. In this dissertation, the problem of identifying the critical k-transmission lines that fail one after another in quick succession, and the distribution system restoration problem using tie-lines/sectionalizing switches formulated as a mixed-integer non-linear programming problem (MINLP) that determines load shed under various k-line removal scenarios are solved. These problems are combinatorial that have huge search space, and solution through enumeration is intractable for large power systems. For reduction of search space, the following mathematical tools are derived, (i) two power flow methods due to k-transmission line removal using the sparse perturbation matrices and power flow sensitivities, (ii) a power flow sensitivity namely k-th order LODF computed using a vector of non-zero numbers stored from the matrix multiplication terms of the first-order sensitivity equation for single line removal cases which reduces its computational complexity, and the sensitivity is computed for any k-line removal case without the necessity of storing it for all k-line removal cases, and (iii) a topological metric based on Laplacian of unweighted graph to identify some important lines between highly connected subgraphs whose disconnection partitions the power system into a few islands. Algorithms are presented using these mathematical tools to identify a reduced number of k-transmission lines in linear time that initiate cascading overload failure and islanding of power system, that are used to solve the MINLP iteratively for identification of critical k-line contingencies as compared to the exponential time complexity of brute-force search for solutions of the MINLP. To reduce the complexity of the restorative problem, a method is developed that exploits the information on pre-contingency power flow solution, network topology together with post-contingency line congestion requirements, and in combination with a greedy search algorithm, which reduces the search space of the problem. Case studies show that the algorithms significantly reduce the search space and computation time of the MINLPs.

Decreasing costs of renewable energy resources and net-zero emission energy production policy, set by U.S. government, are two preeminent factors that motivate power utilities to deploy more system- or consumer-centric distributed energy resources (DERs) to decarbonize electricity production. Since, deep energy decarbonization cannot be achieved without high penetration of renewable energy sources, utilities should develop and invest in new business models for power system operation and planning during the energy transition. Considering the pathways to deeply decarbonize power systems, first, this dissertation proposes a novel hierarchical peer-to-peer (P2P) energy market design in active distribution networks. The framework integrates the distributional locational marginal price to a multi-round double auction with average price mechanism to integrate the network usage charges into the bills of customers. Second, this dissertation investigates the role of grid-integrated hydrogen (H2) systems for improved utility operations and to supply fuel to transportation sector. Power quality concerns as well as risk of uncertain parameters are considered using conditional value at risk based epsilon constraint method. Third, this dissertation proposes a bi-level proactive rolling-horizon based scheduling of H2 systems in integrated distribution and transmission networks considering the flexibility of these assets as controllable load or generation, in addressing the utility operators' normal and emergency operation signals. Fourth, a detailed model is developed for grid-integrated Electrolyzer considering polarization curve and non-linear conversion efficiency of these assets in the P2P enabled distribution network. This framework shows that reasonable penetration of P2P energy exchanges can significantly lower the H2 production cost. Finally, this dissertation proposes a cyber-physical vulnerability assessment of P2P energy exchanges in an unbalanced active distribution networks. Simulation results of this dissertation show the effectiveness of the proposed frameworks.

The adoption of plug-in hybrid electric vehicles (PHEV) as a means of transportation over conventionally fueled vehicles introduces new challenges to the existing infrastructure of the electrical transmission and distribution system. PHEV battery charging can represent a significant power demand that has the potential to overload electrical distribution components. This study examines the impacts of PHEV charging on household service transformers, distribution conductors and voltage levels of a Central California residential distribution system. The system is simulated using ETAP power system analysis software. Transformers are the most vulnerable to overloads, especially if PHEV charging occurs in clusters. Main feeder conductors will be overloaded if a large amount of high power, quick charging occurs. Branch conductors will not be affected by PHEV charging. Based on current PHEV market projections for the region this study shows that significant equipment overloads are not likely to occur until well after 2017.

The power requirements for the microprocessor have been increasing as per Moore's Law. According to International Technology Roadmap (ITRS), the Voltage Regulator Module (VRM) for the microprocessor will be 200 W(with 1V, 200A output) in 2010. With the VRMs topology of synchronous buck, serious technical challenges such as small duty cycle, high switching frequencies, and higher current demands, contribute to decreased power density and increased cost. This thesis proposes a Multiphase Multi-Interleave Buck topology to solve the technical challenges of powering future microprocessors. The critical design parameter values are selected using the theoretical design equations and calculations. The design is simulated in OrCAD Pspice to evaluate the performance criteria of the VRM. A prototype of four-phase Multiphase Multi-Interleave Buck Converter is constructed. The critical performance parameters of the prototype are tested and measured. The thesis concludes with the performance of the prototype as compared with the performance of the design simulation.

There is a growing focus on the need for buildings to be energy efficient due to rising energy prices and the recognition of global warming. Over the past twenty years the sector that saw the least improvement from energy efficiency measures in Canada was commercial and institutional buildings. Though there are many contributing factors, they tend to stem from a lack of available information on building energy usage. In order to rectify this situation more information would be needed to better tune building energy efficiency measures to commercial buildings. Most current research on building energy usage focuses on building consumption, building energy models, or direct measurements from residential buildings. There is little research on measuring a building energy balance of commercial buildings even though the commercial sector accounts for 20% of the overall building energy consumption in Canada. At present, all industry standards focus on the consumed energy in a building, generally natural gas and electricity consumption. Buildings consume energy to meet the demands for occupant comfort within the building and there are many different energy flows and parameters that affect the occupants’ comfort within a building. Solar gain, conduction and infiltration are some of the energy flows that can negatively affect a building’s temperature for occupants, reducing their comfort. In order to reduce the consumed natural gas and electricity, more information on the impact of these energy flows and parameters within a building is required. A five step process was developed to guide the design of an in-situ system that is capable of measuring a complete energy balance of any commercial or institutional building. The focus in this research project is to create an accurate, cost effective sensor array that is a permanent fixture within a building. By utilising these semi-permanent sensors, the interactions between the different energy flows can be better understood. It will also generate more concrete evidence on energy flows to potentially improve building automation systems. In addition to the process, a case study of the Hatch Centre on McMaster University’s campus was completed, giving concrete examples that help to illustrate the procedure. / Thesis / Master of Applied Science (MASc)

In this study, a standard bulk FET design is fabricated with a piezoelectric gate, allowing a microwave-frequency voltage signal to be transmitted from a transducer to the transistor via acoustic conduction through the substrate. Using a single polycrystalline aluminum nitride film as the piezoelectric material, microwave-frequency piezoelectric transducers were fabricated in parallel with piezoelectric FETs. These device pairs function by generating high frequency acoustic waves in the substrate via application of AC voltage to the transducers; the transistors then recover these signals by detecting these waves in their gates via the piezoelectric film, reproducing an attenuated version of the original voltage signal. By taking advantage of the active nature of the transistor and properly controlling the gate and drain bias voltages to maximize gain, the signal recovered by the transistor can be amplified beyond what is passively recovered. In this paper, the design, fabrication, and testing processes for these devices are described at length; the results of these processes, demonstrating devices equivalent to standard FETs that are capable of harnessing incident acoustic waves to generate AC voltages at microwave frequencies, are also presented.

Energization can be described as a form of integrated energy delivery. In the case of the KwaBhaza Pilot Project, PV and LPGas were combined. in a package and offered to rural households. While the approach to off-grid electrification and distributed energy services tends to emphasise the technical aspects of delivery (Kotze 1998), this work provides some insight into the anthropological aspects that hinder the implementation of such initiatives. In this context, 'anthropological aspects' do not refer to cultural conditions in the field but rather the anthropology of development, expressed as a holistic examination of the project and a critical assessment of the development framework within which it operates. It is with this in mind that the objectives of energization, as a development initiative, are thoroughly explored.

According to the US Energy and Information Administration, between 2022-2023 60% of planned new electricity generation consists of solar farms with a battery energy storage system [1]. The demand for these paired systems has increased since batteries can be charged during the day with the energy captured from the solar farm then released to the customer in the evening during peak energy demand. This achieves peak load shaving which reduces the cost of electricity for the customer and is ecologically friendly. This thesis aims to create an efficient solar farm with a battery energy storage system for a farmer in California that achieves peak load shaving. Full cell modules and half-cell modules were explored to determine the type that best suits this project. The half-cell modules were best suited because of the increased efficiency. Six different solar farm designs were created, four fixed tilt designs and two single axis tracking designs. Two types of software, System Advisor Model (SAM) and REopt, were compared to determine which would be most useful in simulating these designs. It was concluded that System Advisor Model (SAM) would be the most accurate to simulate the six designs and produce metrics such as the annual energy production, capacity factor, DC to AC ratio, and levelized cost of energy. The final design, design 6, a 2-string single axis tracking design produced the best metrics that met the project requirements and a battery energy storage system was sized for the design.