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This paper presents a comprehensive analysis and comparison between the 2-level voltage source inverter, 3-level neutral point clamped, and 3-level active neutral point clamped inverters in traction inverters. In this comparison Silicon Carbide MOSFET, Gallium Nitride MOSFET and Silicon IGBT are employed. An analytical method for calculating the inverter power loss is also presented in this paper. Simulation results are conducted using MATLAB/Simulink and PLECS at different operating conditions. A permanent magnet synchronous motor is used as the load. The analysis and comparison have been conducted at different operating points regarding the speed and torque. The performance of each inverter topology is also investigated at different switching frequencies for these operating conditions. Moreover, two drive cycle analyses are also studied and included in this paper.

AC-DC power electronic converters are widely used for electrical power conversion in many industrial applications such as for telecom equipment, information technology equipment, electric vehicles, space power systems and power systems based on renewable energy resources. Conventional AC-DC converters generally have two conversion stages – an AC-DC front-end stage that operates with some sort of power factor correction to ensure good power quality at the input, and a DC-DC conversion stage that takes the DC output of the front-end converter and converts it to the desired output DC voltage. Due to the cost of having two separate and independent converters, there has been considerable research on so-called single-stage converters – converters that can simultaneously perform AC-DC and DC-DC conversion with only a single converter stage. In spite of the research that has been done on AC-DC single-stage, there is still a need for further research to improve their performance. The main focus of this thesis is on development of new and improved AC-DC single-stage converters that are based on multilevel circuit structures (topologies) and principles instead of conventional two-level ones. The development of a new DC-DC multilevel converter is a secondary focus of this thesis. In this thesis, a literature survey of state of the art AC-DC and DC-DC converters is performed and the drawbacks of previous proposed converters are reviewed. A variety of new power electronic converters including new single-phase and three-phase converters and a new DC-DC converter are then proposed. The steady-state characteristics of each new converter is determined by mathematical analysis, and, once determined, these characteristics are used to develop a procedure for the design of key converter components. The feasibility of all new converters is confirmed by experimental results obtained from proof-of-concept prototype converters. Finally, the contents of the thesis are summarized and conclusions about the effectiveness of using multilevel converter principles to improve the performance of AC-DC and DC-DC converters are made.

System reliability and design optimization are the main concerns in power electronic converters of more-electric aircraft (MEA). The fundamental distribution networks of aircraft are reviewed to establish context. The Isolated DC-DC converters are considered the building blocks of modern aircraft electrical power distribution systems (EPDSs). The DC/DC converters transfer power from the main generation direct current (DC) bus to various loads aboard the aircraft. As a result of the electrical power demand increase in the emerging EPDSs of MEA architectures, more energy storage systems (ESSs) are utilized in the distribution network. A single DC/DC converter unit is conventionally dedicated to each energy source. This thesis focuses on replacing several DC/DC converters used in the existing distribution networks by more optimized multi-source converter units. Standard industry and literature topologies are reviewed including structures aimed for multi-source system integration. The topology proposed in this thesis aims for a multiple sources/loads integration to improve the power density of the distribution network. The different operating modes of the proposed topology add flexibility to the system enabling power flow between different sources, while controlling the power supplied to the low voltage (LV) network on the aircraft. Better system utilization is achieved as compared to conventional solutions. The system stability is improved considering that the multi-source dual active bridge (MSDAB) topology can be configured to stabilize the high-voltage DC (HVDC) generation bus in case of voltage sag. A power-flow mechanism between the different sources utilizing the magnetizing inductance of the transformer is proposed and discussed as one of the operating modes of the converter. A design process using genetic algorithm (GA) optimization is introduced to optimally select the converter parameters to minimize the converter RMS current. The mathematical model of the proposed MSDAB topology is developed based on Fourier transform of key converter waveforms. The optimization is split into two layers; the first is to select the hardware components and the second is to optimize the converter control parameters. Simulation and experiments of the control schemes were performed to validate optimal operation of the proposed converter. A review of the magnetic components in MEA DC/DC converters is conducted. The high-frequency transformer utilized in such converters is the major contributor to the size and weight besides the thermal management system. An optimization design methodology is introduced to minimize the transformer core size and improve the converter performance through optimized winding configurations. Different magnetic materials, winding configurations, and core paralleling are considered in the optimization process. The trade-offs between the converter efficiency and transformer power density are discussed. The transformer parasitic elements effect on the converter performance is presented. Multi-layer minimum gradient (MLMG) winding configurations are proposed to eliminate the high-frequency oscillations (HFO) caused by the transformer parasitics. The proposed configurations resulted in better converter performance with 20$\%$ improvement in the transformer volume as compared to a similar conventional configuration. Three different transformer configurations are implemented and validated experimentally using an impedance analyzer. The improvements in the converter performance are highlighted through finite element analysis (FEA) simulations and converter experiments. Thesis Doctor of Engineering (DEng)

This thesis presents the development of an advanced control structure for the novel Integrated Community Energy and Harvesting (ICE-Harvest) system. The ICE-Harvest system is similar to a District Energy (DE) system in many ways and is different in others. It consists of a set of energy producing and storage units coupled to a thermal network which connects residential and commercial buildings of various types. Its operation is geared towards addressing challenges associated with the current energy landscape in Ontario, with potential to be applicable elsewhere in Canada. The control of this system is based on the implementation of a Multi-Agent System (MAS) combined with Sequential Logic Controllers (SLCs). Results demonstrate the capability of the developed control framework to operate the ICE-Harvest system while ensuring the thermal and electrical energy supply to the different consumers. Based on the results presented, the operation of the ICE-Harvest system by the developed control framework is compared with that of a Business-As-Usual (BAU) scenario. This comparison demonstrates the capability of the developed control framework to operate the ICE-Harvest system in a way that also increases the energy utilization and reduces emissions. Thesis Master of Applied Science (MASc)

Traction inverter, as a critical component in electrified transportation, has been the subject of many research studies in terms of topologies, modulation, and control schemes. Recently, some of the well-known electric vehicle manufacturers have utilized higher-voltage batteries to benefit from lower current, higher power density, and faster charging times. With the ongoing trend toward higher voltage DC-link in electric vehicles, some multilevel structures have been investigated as a feasible and efficient option for replacing the two-level inverters. Higher efficiency, higher power density, better waveform quality, and inherent fault-tolerance are the foremost advantages of multilevel inverters which make them an attractive solution for this application. The first contribution of this thesis is to investigate and present a comprehensive review of the multilevel structures in traction applications. Secondly, this thesis proposes an electro-thermal model based on foster equivalent thermal networks for a designed three-level active neutral point clamped (ANPC) inverter, as well as a modified sinusoidal pulse-width modulation (SPWM) -based technique. This electro-thermal model and the modulation technique enable temperature estimation in the inverter and minimization of the hotspot temperature and hence, increase the power density. Based on the experimental results derived from the implemented setup, a 12% increase in power density is achieved with the proposed technique. The other contribution is a reduced-complexity model-predictive controller (MPC) for the three-level ANPC inverter without weighting factors in which the number of calculations has dropped from 27 to 12 in each sampling period. The improvements to the structure and control system of the inverter are supported by theoretical analysis, simulation results, and experimental tests. A three-level inverter is implemented for 800 V, 70 kW operation and tested. 750 V Silicon Carbide (SiC) switches are utilized in the inverter structure. Finally, future trends and suggestions for the following studies are stated in this thesis. Thesis Doctor of Philosophy (PhD)

Multilevel inverters (MLI) are the foundation of motor drives in medium and high-voltage applications, allowing low voltage devices in high power applications. The Cascaded H-Bridge (CHB) is a multilevel inverter with significant popularity and unique advantages due to its modular structure. The modularity of the CHB allows a scalable design that accommodates various power ratings with minimal changes. In a typical CHB, a six-pulse diode rectifier and an H-Bridge inverter provide power from the grid to the load. As a diode rectifier only allow unidirectional power flow, the typical CHB is confined to only receiving power from the grid. The unidirectional nature of the typical CHB can propose energy loss if used in regenerative applications. A regenerative CHB with two-level voltage source inverters rather than diode rectifiers has been introduced to address the unidirectional power flow. However, this solution proposes a significant increase in the system's complexity, cost, and size. As the demand for efficient energy increases, the research on more suitable-sized and economical regenerative CHBs has gained substantial attention. In this thesis work, two new reduced switch-count regenerative CHB power cells are proposed. Both proposed power cells reduce the number of switches per cell by four. The challenges that arise are addressed by introducing new control and carrier phase-shifting techniques. The switch-count reduction aims to reduce the complexity, cost, and size of the conventional regenerative CHB. The theoretical analysis and simulation studies demonstrate the potential of the new reduced switch-count regenerative power cells and its capability to replace the conventional regenerative CHB power cell. Experimental validation of one of the proposed power cells is conducted with a single-cell configuration. The experimental result for conventional regenerative, three-phase reduced switch-count and the new proposed power cells are presented to compare their operation. The future work of this thesis includes experimental validation of the new proposed power cell in a 7-level regenerative CHB drive and operation of the system with a regenerative motor load. Thesis Master of Applied Science (MASc)

The electrification of transportation is increasingly of interest to governments around the world as a means of contributing to the achievement of climate change goals. Transportation is a significant source of greenhouse gas emissions, but it is also the backbone of the global economy and local mobility. Electrification is widely seen as a promising pathway to reducing greenhouse gas emissions from transportation while continuing to support economic growth. Multiphase machines have distinctive features that draw attention in the transportation electrification domain due to their features. Recently, powertrains based on the current-source inverter (CSI) are getting more attention to be a more reliable structure for Electric Vehicles (EVs) by replacing the dc-link capacitor with a choke inductor. This thesis combines these two technologies to develop a more reliable, compact powertrain for heavy-duty electric vehicles. First, a survey covers the recent advances in several aspects such as topology, control, and performance to evaluate the possibility and the future of exploiting them more in EV applications. The six-phase drives are extensively covered here because of their inherent structure as a dual three-phase system which eases the production process. The survey presents the different topologies used in dual three-phase drives, the modulation techniques used to operate them, the status of using multiphase drives in traction applications industrially, and the upcoming trends toward promoting this technology. New powertrain configurations for heavy-duty electric vehicles (HDEV) are proposed based on current-source inverters (CSI) and asymmetrical six-phase electric machines. Since the six-phase CSI comprises two three-phase CSIs, multiple configurations can arise based on the connection between the two CSIs. In this context, the proposed powertrain configurations are based on parallel, cascaded, and standalone six-phase CSIs. The standalone topology is based on separating the two three-phase converters by supplying each converter with a dedicated dc-dc converter. A new and straightforward method is proposed to extend the six-phase standalone CSI. The proposed technique employs the vector space decomposition (VSD) to mitigate the inverter current harmonics and extend the linear modulation region by about 8%. For motor drive applications, increasing the fundamental output component can reflect higher torque production capability for the same drive size, given that thermal limits are not exceeded. Moreover, to increase the drive's reliability, space vector modulation (SVM) techniques are developed to operate the six-phase CSI while reducing the common-mode voltage (CMV) content associated with the switching of semiconductors. The SVM techniques select the switching states associated with the minimum CMV value offline to eliminate the need for measurements. Experimental validation of the proposed algorithms is presented to operate a scaled-down six-phase PMSM fed by the proposed powertrain configuration. These proposed techniques make the CSI- based powertrain a promising solution for future HDEVs in terms of cost, performance, and reliability. Thesis Candidate in Philosophy

High power converters are widely used in many industries. At power levels in the range of Mega Watt (MW), power conversion at medium voltage (MV) is preferred due to better efficiency and lower cost. For medium voltages applications, multilevel converters are widely adopted due to the features they offer with respect to two-level converters. Cascaded H-bridge topology is a widely adopted multilevel topology because of its modularity, scalability, and reliability. The conventional cascaded H-bridge topology allows two-quadrant operation. In order to allow fourquadrant operation, an active front end version of the cascaded H-bridge topology has been proposed in literature and recently commercialized. In the field, power converters operates under harsh loading and environmental conditions. The resulting stresses imposed on converter components cause their gradual degradation. In cascaded H-bridge converters, typically power cell components such as power modules, DC-bus capacitors, and control PCBs are v highly stressed. Under these stresses power cell components degrade and require replacement in the field, otherwise unexpected failures may occur. The thesis aim is to address power cell components reliability through proposing novel regenerative cascaded H-bridge converter control schemes to reduce components stresses and failure probability without increasing size, cost, or complexity. First, a novel PWM active front end control scheme has been proposed to reduce the inherent ripple current stresses on the DC-bus capacitors. Second, the thesis proposes a novel grid or near grid switching frequency front end control scheme to reduce stresses on power modules and the power cell cooling requirements. Third, novel cascaded H-bridge front end control schemes are proposed to reduce the sensor count, thereby decreasing failure rate and cutting down cost. The proposed work has been thoroughly validated through detailed 9- cell regenerative cascaded H-bridge system simulation and experimentation. Thesis Doctor of Philosophy (PhD)

Wireless charging of the EVs offers a convenient, reliable, and automatic charging of the autonomous vehicles without user interference. The focus of this thesis is the design and optimization of new structures for stationary EV wireless charging applications. The fundamentals of the Wireless Power Transfer (WPT) system and its main components including the magnetic couplers, transmitter and receiver power converters, and control methods are studied in depth. The requirements of the EV wireless charging application and design criteria are discussed in detail. The advantages and disadvantages of each topology are highlighted, and possible candidates for EV wireless charging applications are selected. Optimization of the resonant networks in terms of maximum efficiency and misalignment tolerance is studied. Different resonant topologies are studied in detail and their sensitivity functions are extracted. For each topology, an efficiency model is presented that includes the inverter, resonant capacitors, resonant inductor, diode-bridge, and core and conduction losses. Each topology is optimized with two different objective functions and the results are compared through the simulation and experiments. According to the optimization results, suitable topologies for the EV wireless charging application are selected. In order to increase the power density of the wireless charging system, and save ferrite material, integrated inductors into the magnetic couplers are proposed. In this structure, the DC-DC inductor is integrated into the receiver main coil and the resonant inductor is integrated into the transmitter coil. This integration introduces new challenges to the design of the resonant network and magnetic coupler due to the unwanted cross-coupling effect. To address this issue, the fully integrated magnetic structure is optimally designed to have minimum cross-coupling. Moreover, the resonant network is designed based on an optimization problem that includes the cross-coupling into the system equations to ensure maximum efficiency. The proposed fully-integrated magnetic structure is built and experimental tests are presented to validate the performance of the proposed magnetic structure and its optimization method. To reduce the implementation cost, size and weight a PCB-based magnetic coupler is proposed to replace the Litz wire in the magnetic coupler of the WPT system. Moreover, the proposed PCB-magnetic coupler increases the repeatability of the design and reduces manufacturing errors. The PCB-based magnetic coupler is studied through Finite Element Analysis (FEA) to minimize the AC resistance of the coil. Different parameters such including the number of the PCB layers, copper cross-section, and layer thickness are studied in detail to evaluate their effect on the coil resistance. Thermal analysis is performed to ensure the feasibility of the design under different loading conditions. A 3.3 kW/85 kHz wireless charging system is built and experimental tests are presented. A novel modular resonant topology for fast wireless charging is proposed. A modular structure offers reliability, scalability, and better thermal management. The proposed topology is made by multi-parallel inverter legs connected to an LCC resonant network. The outputs of the resonant networks are connected in parallel to feed the transmitter coil with a high excitation current. The proposed modular system is compared with a conventional system and it showed superior performance in different aspects. Thesis Doctor of Philosophy (PhD)

For an Electrical Vehicle, the power is delivered from the battery pack to the electric motor through the use of power converter. Many research projects have been conducted in improving the efficiency of traction inverters. Inverter topologies are categorized based on the number of voltage levels of the inverter output phase voltage. The conventional 2-level Voltage Source Inverter (VSI) is commonly used as a traction inverter due to its simple structure. Due to the recent trend in utilizing higher DClink voltage in traction motor drives to achieve a higher power rating, multi-level inverters are gaining attention to replace the conventional VSI in EV powertrain. Multi-level voltage source inverters (MLVSI) have been widely adopted in high-power converters and medium-voltage drives. There are four major categories of MLVSI: the Flying Capacitor (FC), Neutral Point Clamped (NPC), Cascaded and Hybrid. The power rating of the MLVSI increases with the increase of inverter levels, but the size, number of switching devices, cost and control difficulty also increases. Due to the above reasons, 3-level NPC can be a good solution for traction inverters. Due to the structure and control limitation, Diode Clamp NPC suffers from uneven loss distribution and neutral point voltage balancing issues. This issue can be resolved with Active Clamped NPC (ANPC). In this thesis, the design, simulation, prototyping and testing of a 70kw 3-level ANPC traction is introduced. Thesis Master of Science (MSc)

Medium-voltage (MV) motor drives have found widespread applications in various heavy industries, such as in the oil and gas sectors, production plants, and process industries. Conventional cascaded H-bridge (CHB) multilevel inverters dominate the medium-voltage industrial drives domain due to their modularity, scalability, and reliability. The most prevalent CHB topology in the drive industry is based on the diodes-front-end (DFE) rectifier, which greatly limits the industrial application of the conventional CHB drives where the ability of handling regeneration is required. The main objective of this thesis is to develop a low-cost, high performance, reliable regenerative CHB drive. The thesis is concentrating on reducing the grid-tied filter size, shrinking the DC-link capacitors, improving the system’s performance and reliability through advanced control techniques. First, to reduce the number of passive filter components, a new sideband harmonic active filtering strategy based on the carrier-shifting method is proposed for regenerative CHB drives. This proposed approach extends the carrier shifted PWM method for regenerative CHB drives to further reduce the required passive filter size significantly and thus improves the overall size, cost, and efficiency while complying with IEEE Std 519-2014 grid standard. Second, a novel voltage ripple controller is proposed to reduce the dc-link capacitance in the three-phase regenerative CHB drive without adding extra measurements. Third, to achieve a faster dynamic response and the multi-objective performance during the control of CHB drives, a novel high-performance predictive control with long prediction horizons is proposed to improve the control performance of the CHB multilevel inverters. The formulation of the proposed high-performance finite control set model predictive control (FCS-MPC) is explained in detail and analyzed to reduce the real-time computation burden. Last, when a fault is detected in the regenerative CHB drive system, the reliability and fault-tolerant ability are considered as the main issues. To improve the drive system reliability, a non-symmetrical selective harmonic elimination (SHE) formulation is proposed to extend the output voltage range with a good harmonic profile under post-fault conditions. Experimental validation of the proposed algorithms is presented for the operation of a scaled-down seven-level regenerative CHB drive system. These proposed techniques make the regenerative CHB drive a promising solution for future medium-voltage regenerative drive applications in terms of cost, performance, and reliability. Thesis Doctor of Philosophy (PhD)

The inevitable choice for the automotive industry to suppress greenhouse gas emissions is zero-emission vehicles such as battery electric vehicles. Some of the main barriers regarding the adoption of electric vehicles are range anxiety, and lack of charging infrastructure, which can be addressed by ultra-fast chargers or charging stations. The conventional ultra-fast chargers are low-voltage (LV) connected through line-frequency transformers, which pose disadvantages such as low efficiency, high cost, and large footprints. The medium-voltage (MV) connected charging station is proposed by the researchers to overcome the challenges regarding the conventional chargers by eliminating the line-frequency transformer and direct connection to the medium voltage. The most challenging part of the medium-voltage ultra-fast chargers is the AC/DC stage connection to the medium voltage. Different medium-voltage multilevel converters have been proposed to facilitate the direct connection to the medium-voltage grid. However, disadvantages such as a high number of components and control complexity weaken the strength of medium-voltage connected stations. The main focus of this thesis is on novel advanced medium-voltage multilevel topologies and control techniques for medium-voltage connected ultra-fast EV charging applications. First, a novel controller based on SPWM is proposed to control the flying capacitor voltages of a four-level T-type Nested Neutral Point Clamped (NNPC) topology. Second, a new five-level T-type NNPC topology is proposed that has a minimum number of components in comparison to other existing five-level topologies. To extend the voltage and power rating, a novel seven-level topology is proposed that has the lowest number of components in comparison to other existing topologies. Moreover, three different controllers are developed to control the voltages of the seven-level topology based on Model Predictive Control, where the challenges regarding significant computational burden and weighting factor elimination are addressed. Finally, an MV-connected ultra-fast charging station architecture is proposed, where the proposed seven-level topology is considered as the AC/DC stage. Comparison of the proposed topology to the LV-connected stations shows that the efficiency, cost, and power quality of the charging stations can be improved significantly. Thesis Doctor of Philosophy (PhD)

Cascaded H-bridge (CHB) multilevel inverters have significant popularity with motor drives applications due to their modularity, scalability, and reliability. Typical CHB inverters employ diode rectifiers that allow unidirectional power flow from the grid to the load. To capture and utilize the regenerated energy in regenerative applications, regenerative CHB drives were introduced with two-level voltage source converters in the front end to allow bidirectional energy flow. This solution is accompanied by challenges of high number of switches and control circuits, high switching power losses, and massive dimensions. Recently, developing more economic versions of regenerative cascaded H-bridge drives has become one of the hottest topics in power electronics research. In this thesis work, two solutions are proposed for more energy efficient and economic regenerative CHB drives. The first solution is a proposed power cell configuration that reduces the number of switches per cell by two. Additionally, phase alternation connection method and carrier phase-shifting techniques are introduced to address the challenges of the presented configuration. The switch-count reduction reduces the system’s complexity, switches’ cost, and footprint. The second proposed solution is a new controller to operate the front-end converters as fundamental frequency ends (FFEs). The proposed controller is employed in both the conventional regenerative cascaded H-bridge and the proposed reduced switch-count configuration. This solution minimizes the switching power losses, and results in more compact and economic design, with higher DC-link utilization. Theoretical analysis and simulation studies of both proposed solutions show promising performance and capability to be applied as energy-efficient and cost effective regenerative CHB motor drives. Experimental validation of the proposed reduced switch-count configuration is presented for STATCOM operation of a scaled-down 7-Level regenerative CHB drive system. The future work of this thesis includes experimental validation of the proposed FFE controller, and operation of the system with regenerative motor load. Thesis Master of Applied Science (MASc)

This work proposes a new approach to fast detection of abnormal behaviour of cooling, IT, and power distribution systems in micro data centers based on machine learning techniques. Conventional protection of micro data centers focuses on monitoring individual parameters such as temperature at different locations and when these parameters reach certain high values, then an alarm will be triggered. This research employs machine learning techniques to extract normal and abnormal behaviour of the cooling and IT systems. Developed data acquisition system together with unsupervised learning methods quickly learns the physical dynamics of normal operation and can detect deviations from such behaviours. This provides an efficient way for not only producing health index for the micro data center, but also a rich label logging system that will be used for the supervised learning methods. The effectiveness of the proposed detection technique is evaluated on an micro data center placed at Computing Infrastructure Research Center (CIRC) in McMaster Innovation Park (MIP), McMaster University. Thesis Master of Science (MSc)

Since the late 1990s, lots of attention has been given to the development of multi-phase motor drives due to the momentous interest in developing greener methods of transportation and the increased benefits when compared to their three-phase counterparts. These benefits include improved fault-tolerant control, reduced torque ripple, improved motor power density, and reduced DC-link capacitance which has resulted in an amplified interest in multi-phase machines for electric ship propulsion, electric aircraft, and traction electric motors (electric and hybrid road vehicles). When looking specifically into multi-phase machines that are made up of six-phases, different topologies have been researched that include altering the phase shift between the different windings or winding sets as well as the number of neutral points within the machine. Out of all possible combinations, there are three common six-phase machine topologies studied in the literature. First is the six-phase machine with a 60 degree phase shift between each of the machine windings – referred to as an asymmetrical six-phase machine. The second and third topologies are a six-phase machine with two sets of three-phase windings where one winding set has a phase shift from the other winding set (typically 30 degrees. When the two winding sets have a shared neutral point, the machine is referred to as an asymmetrical six-phase machine. Alternatively, when the two winding sets have isolated neutral points, the machine is referred to as a dual three-phase machine. From the recent surge in the literature regarding the added benefits of the dual three-phase machine compared to the other six-phase topologies, this thesis will mainly focus on the control and switching techniques specifically for the dual three-phase machine. With an in-depth analysis, the effect of different switching techniques will be observed on the overall efficiency of the six-phase voltage source inverter (VSI). Furthermore, using the Matlab/Simulink and PLECS environment with a dual three-phase drive system vector space decomposition (VSD) based model, an accurate drive model that incorporates the machine's dynamic behaviour and calculates the total losses of the VSI is also proposed. The VSI is connected to a 100 kW dual three-phase interior permanent magnet synchronous machine (IPMSM) and different switching techniques are applied to the inverter to properly control the six-phase drive system. Similar to their three-phase counterparts, dual three-phase machines can be controlled using sinusoidal carrier-based pulse width modulation (SPWM) and space vector pulse width modulation (SVPWM). This thesis explores the VSI efficiency when using different switching techniques proposed in the literature and proposes new techniques to improve the efficiency of the VSI. Additionally, a detailed plan for an experimental setup and testing procedure is provided for the switching techniques that are simulated throughout this thesis. This proposed testing procedure assumes a prototype six-phase VSI composed of six Infineon FF600R12IE4 IGBT modules that are connected to a dual three-phase 100 kW IPMSM. As the future work of this thesis includes experimental verification, the Matlab/Simulink drive model proposed in this thesis is designed with this particular setup in mind. Thesis Master of Applied Science (MASc)

Integration of optical wireless communications (OWC) within switched-mode power supplies (SMPS) Although visible light communication(VLC) systems can provide high density links for use with IoT devices, an energy efficient, high rate method of designing a VLC transmitter is still unclear. Present designs for transmitters such as the bias-T, designs with switch manipulation, and interleaved converters are not commercially viable due to costly and complex designs that sacrifice energy efficiency for data rate. A design allowing for efficient, high rate communications, while maintaining a low cost would allow for widespread adoption of this technology. In this thesis, a novel approach of integrating power converters and VLC systems is explored by replacing commutating diodes with LEDs. By leveraging switched-mode power supply(SMPS) structures, the power dissipated within the converter may be harnessed and used for communications. The result is a simple and energy efficient solution capable of high rate links. Simulation and experimental results demonstrate buck and boost SMPS topologies that simultaneously increase energy efficiency and provide communications at SMPS switching rate without increasing component count. Thesis Master of Applied Science (MASc)

This thesis suggests a new approach to extend the lifetime of Lithium-ion batteries for a Home Energy Storage System equipped with a renewable energy source. The new configuration improves the lifetime of the energy storage device by using the pulsed charge-discharge method. The batteries in this system can be charged either using solar panels when solar energy is available or by the grid power during off-peak hours when the electricity cost is at its lowest rate. In the new configuration, the battery bank is split into two equal sections to employ pulsed charge-discharge method. Interrupting the charge or discharge current provides a relaxation time for the lithium ions to diffuse gradually into the electrodes material of Lithium-ion batteries, this reduces the damage in the microstructure of the electrodes and thus it helps to prolong the battery lifetime. The spilt bank strategy improves the longevity of Lithium-ion batteries while maximizing the solar energy utilization. This strategy leads to reduce the reliance on the grid power which decreases the consumer’s total energy cost as well. To show the usefulness of the new approach, different modes of operation are discussed in details along with simulation results. An experimental setup is also developed to evaluate the effectiveness of the new approach in extending the Lifetime of Lithium-ion batteries. Thesis Master of Applied Science (MASc)