Heavy industry is responsible for about a third of global emissions but lags behind in its effort to become carbon neutral. The electrification of industrial processes is a necessary step to achieve this goal. The asphalt industry is a good candidate for decarbonisation, as it currently relies on burning fossil fuels to heat and dry the aggregate used in asphalt production. Instead, aggregates could be heated electrically by using induction heating.

This thesis will investigate the design of an aggregate induction drum heater. A COMSOL model will be developed to aid the design process and predict the heater behaviour. The heater will be powered by a resonant converter, which is modelled in Simulink. A test setup is built to serve as a proof-of-concept for the design and to experimentally verify the models.

The analysis of the simulation and test results show that the model quality is dependent on the description of the material properties. The COMSOL model predicts the temperature of the middle of the heater with reasonable accuracy while the Simulink model is able to simulate the coil current and converter voltage waveforms with little error. The design of the aggregate induction heater could be improved by thermally insulating the outside surface and increasing the contact area between the aggregate and the heater.

One fifth of the global carbon dioxide (CO2) emissions can be attributed to the transportation sector. Consequently, the growing desire to participate in the energy transition begs for the exploration of alternative modes of transportation. This endeavor is particularly challenging in the field of aviation and aircraft propulsion, where the injection of electrification and electric motors (EMs) pose many hardships such as the need for high autonomy, light weight, high power density and reliability. This work will mainly focus on the latter.

Unlike the low voltage machines used in road mobility, the motors necessary to propel an airplane demand substantially higher voltages due to their power requirements. Despite the availability of dielectric materials and insulation techniques, an improper design of the insulation system may make it susceptible to electrical stress, possibly reaching its breakdown voltage, generating partial discharges (PDs) and degrading the insulating material overtime. This will eventually lead to the electrical failure of the machine.

This danger is further increased by the recent rise in popularity of new wide-band gap power electronic devices. These devices offer many advantages: reduced size and weight, the ability to operate in higher temperatures, and the improved efficiency due to the reduction in power losses, caused by their steep switching speed in the order of 10−100 ns. However, the steep voltage transients (dv/dt) they produce create harmful side-effects to the machine. Firstly, the feeder cable connecting the voltage inverter to the machine terminals suffers Reflected Wave Phenomenon (RWP), where the voltage pulses are reflected at both ends of the line generating intereferences, which in turn generate overvoltages that can rise to up to twice the original voltage pulse. Secondly, the inherent leakage capacitance between the cable turns and the core of the stator slots produce an uneven voltage distribution along the wiring turns. These effects could increase the voltage stress in the insulator and momentarily reach the breakdown voltage in certain points of the geometry, producing Partial Discharges (PDs) that degrade the insulation over time.

To avoid this degradation, the aim of this thesis is to study these harmful effects in depth, back-up the literature review with accurate simulations and experimentation and realize the worst case scenario considering the geometry of a given motor that is currently under design. Once the phenomena is understood, some mitigation techniques are proposed to lower the chance of any discharge occurring.

Due to recent developments in current-soruce inverter technology the topology becomes more attractive for use in electric aircraft. However recent studies have shown that electric aircraft are unlikely to be able to operate at high voltages due to the insulation derating, meaning that higher current solutions should be evaluated. In this paper a design is presented that is intended to operate at high currents and lower voltage in order to investigate what influence this shift in operating point has on the functionalit of the inverter. Different design elements are discussed and motivated, including the topology, component selection, and current control methods. After validating the functionality through experimentation the discovered issues are explained and discussed. The design will be shown to be functional, although some of these issues do limit its performance.

As the need for both clean electricity and reduction of carbon emission rises, all-electric airplanes have the potential to reshape the field of aviational transport to fit this need. The development of such airplanes necessitates the advancement of highly reliable and efficient electrical systems, among which circuit breakers play a critical role. This paper investigates design considerations and challenges associated with circuit breakers for all-electric aircraft. The study explores possible circuit topologies that are capable to interrupt a 3 kV and 500 A power flow when a fault in the system causes a short circuit. Through simulations and experimental validations, the paper aims to propose an optimised circuit breaker design that enables reliable electric power systems in all-electric aircraft.

In this thesis, "Design & Reliability Assessment of AEA Propulsion Grid", the development of a reliable and efficient propulsion grid for All-Electric Aircraft (AEA) is investigated to reduce aviation emissions. Our primary objective is to design a lightweight Power Management and Distribution (PMAD) system that meets stringent reliability standards. By analyzing materials, heat transfer, and grid design, we propose optimized grid topologies that balance weight and reliability. The findings emphasize the importance of redundancy and suggest further research into subcomponent failure rates, control aspects, and real-world testing to enhance system reliability and performance. This thesis provides valuable insights into the future of electric aviation, highlighting the necessity for continued investigation and practical application to ensure ultra-reliable electric propulsion systems and make zero-emission flight a reality.

The number of satellites launched every year is ever-increasing. Satellites generate energy through solar panels, transferring it to the satellite hub using Slip Ring Assemblys (SRAs). However, SRAs suffer from limited lifetime and operating voltages. Therefore, this research investigates a Contactless Energy Transfer (CET) system for the satellite to eliminate these problems. The system consists of an input source, inverter, Alternating Current (AC)-link and rectifier. A single diode model is introduced for the solar panel input source to model its behaviour. After a brief comparison, the Inductive Power Transfer (IPT) method is favoured over the Capacitive Power Transfer (CPT) method. As a result, the AC-link includes a transformer to obtain the contactless energy transfer. The Single Active Bridge (SAB) topology is chosen after comparing the characteristics of the SAB and Dual Active Bridge (DAB) topologies. Afterwards, two SAB converters, the Single Active Bridge with Output Inductor (SABL) and LLC converter, are compared before choosing the LLC converter. With the CET system design completed, the design procedure for the LLC converter is presented, resulting in transformer requirements. A coaxial solenoid transformer design procedure where the inductance and losses are modelled is used to create a prototype transformer. The models are validated using Finite Element Method Magnetics (FEMM). The designed transformer met the inductance requirement. However, the losses were too significant to meet the overall CET system efficiency requirement.

The electric vehicle (EV) market has experienced significant expansion in recent years, underscoring the pressing need for advanced EV charging infrastructures. In addition to conductive charging, wireless EV charging has proven to be a promising charging solution as it provides safe, convenient, and automated charging for EVs. The most commonly adopted technology for wireless EV charging is inductive power transfer (IPT). Moreover, in wireless EV charging systems, achieving a wide operating range is imperative due to several contributing factors. Firstly, EV battery loads vary significantly during the constant current-constant voltage (CC-CV) charging process. Secondly, coil misalignment and capacitance drift lead to notable deviations in the parameters of resonant circuits. Thirdly, accommodating diverse EV models to enhance interoperability introduces significant variations in air gaps, receiver coil configurations, and nominal EV battery voltages. These factors collectively expand the operating range requirements for wireless EV charging systems. Nevertheless, ensuring highly-efficient and wide-range operation under these varying conditions is challenging. This thesis aims to address this challenge by implementing advanced control and modulation techniques for power converters and compensation networks in wireless EV charging systems.@en

This thesis presents a practical topology for achieving highly efficient dual-side wireless power transfer (WPT). Traditional WPT systems with a diode rectifier on the secondary side lack flexibility in load matching, requiring the integration of an additional dc/dc converter at the back end. However, this approach leads to increased power losses and costs. In contrast, this thesis proposes the use of an active rectifier comprising MOSFETs, replacing the diode rectifier.

By employing a dual active bridge topology with dual-side control, optimal load tracking is achieved by tuning one side and communicating the desired duty cycle or phase angle to the other side. To address practical challenges, two key aspects are considered.

Firstly, synchronization is established between the generated current on the
secondary side and the new active rectifier, enabling efficient load tracking and the potential for zero voltage switching (ZVS). This is accomplished using a printed circuit board (PCB) equipped with zero current crossing detection (ZCCD), validated with an 85kHz test signal. The PCB triggers the PWM output of the secondary side microcontroller with a latency of less than < 50ns, utilizing the trip-zone digital compare sub-block integrated into the TMS320F28379D.

Secondly, seamless wireless communication between the primary and secondary sides is essential. While the secondary side can measure
the current and voltage across the load to adjust its duty cycle for optimal conditions, the primary side lacks this information. Therefore, the secondary side transmits the new duty cycle to the primary side to
ensure consistent power flow. The nRF24L01+ wifi module is utilized as a dual-purpose transmitter and receiver for achieving wireless communication. Validation of this wireless communication is performed
by remotely controlling an external LED, connected to the receiver side, from a distance of approximately 5m.accurately to the transmitted values. Additionally, a mathematical modeling approach is used to optimize power delivery and mitigate high-frequency noise by incorporating two parallel MLCC capacitors on a custom PCB near the nRF24L01+ module.

This thesis aims to enhance the performance of solar cells, specifically those used by Solarge, through comprehensive research on optical characterization and texture fabrication.
In the first part, the focus is on understanding and optimizing the optical properties of Solarge's polymer front sheet and encapsulant. Through meticulous measurements, both computationally and experimentally, the thickness and optical constants of each layer are determined. This information is used to develop an accurate optical model, validated against real-world measurements, to simulate the performance of Solarge's solar cell stack. Additionally, electrical performance is thoroughly evaluated using a combination of computational and experimental techniques.
The second part of the research delves into the fabrication of textures on Solarge's front sheet to minimize optical losses. Two fabrication methods, release papers and Teflon sheets, are examined, and a diverse range of texture morphologies undergo rigorous experimental testing. These textures are carefully evaluated based on their optical and electrical characteristics. By analyzing the findings from the initial texture analysis, a set of requirements is established to guide further investigations and determine the most effective texture for Solarge's solar cell stack. A computational study is conducted to accurately simulate and analyze different texture geometries, including scaled-up bio-inspired textures, random pyramids, and corner cubes, using the advanced capabilities of GenPro4 software. Based on the results obtained, two texture geometries are recommended to Solarge for further optimization. The implementation of the first recommended texture demonstrates a significant increase of 2.65% in power output compared to the current Solarge cell stack.
A holistic perspective is provided through a simple financial analysis, evaluating the potential profitability and economic feasibility of implementing the recommended improvements outlined in this thesis. The research findings offer practical insights for Solarge, enabling them to enhance module performance, reduce optical losses, and potentially generate substantial revenue.
In conclusion, this thesis presents a comprehensive investigation into the optical characterization and texture fabrication for Solarge's solar modules. The research outcomes contribute to an improved understanding of the optical properties of the cell stack components and the impact of surface texturing on performance. By combining scientific analysis, experimental testing, and computational simulations, this research offers valuable recommendations to enhance the overall efficiency and profitability of Solarge's solar cell stack.

In this thesis, the acoustic noise emitted by a small electric outrunner motor, such as the ones commonly used in unmanned areal vehicles, is analyzed using a multiphysics simulation based on the finite element method. The simulation covers the electromagnetic, mechanical and acoustic domain. The electromagnetic simulation is performed in the 2D time domain, the mechanical simulation in the 3D time domain and frequency domain and the acoustic simulation in the 3D frequency domain. The difference between results of the time and frequency domain mechanical study is investigated, as well as the difference between the obtained results and those obtained in other available literature. Furthermore, the results are compared to acoustic noise measurements performed in the laboratory. Based on the obtained results, noise reduction methods, specifically focussed on small electric outrunner PMSMs, are proposed and verified using the developed simulation.

This Master's Thesis is conducted in collaboration with Alewijnse, a leading maritime systems integrator in the Netherlands. The thesis aims to identify the optimal and cost-effective method of incorporating battery energy storage systems (BESS) into both new and existing DP-2 vessels, as well as DP-3 vessels. The objective is to determine the most efficient battery size and technology, establish the ideal time frame for return on investment, and design a power generation schedule that is ideal for the DP-2 cable laying vessel’s power system.

The primary objectives of this research are to optimize the battery system, ensure effective energy system operation, and establish a strong business case. Specifically, the study explores the feasibility of retrofitting a DP-2 vessel that operates in the North Sea and Taiwan with a battery system to create a hybrid system.

To determine the optimal sizing of the battery energy storage system, 12 different battery solutions from two European battery suppliers considering three different fuel price scenarios are analyzed. These solutions encompass a variety of battery technologies, such as High Power or High Energy Li-ion batteries or a combination of both.

The integration of BESS into vessels offers several operational benefits to operators, including the ability to operate diesel engines at higher or more efficient points of operation to maximize their performance. Battery systems can also act as ”virtual generators” during dynamic positioning (DP) mode for DP-2 vessels, reducing fuel consumption, lowering diesel engine ON-time, and decreasing maintenance costs.

However, hybridizing vessels involves more than just integrating an optimally sized battery system.The existing power management system (PMS) and energy management system (EMS) must also undergo upgrades to ensure effective operation. To address these challenges, the BOOSTER (Battery Optimization for Optimal Sizing and Throughput Energy Regulation) methodology is proposed, which incorporates the operation of an optimized management system based on fuel prices and the throughput energy cost of the battery system.

Emissions caused by regular vehicles with fossil fuels are problematic for the environment. The integration of electric vehicles in public transportation can potentially cause zero emissions. This paper will focus on the implementation of electric buses together with inductive chargers at bus stops. These chargers will charge the bus battery while passengers enter or leave the bus. This is also known as opportunity charging. Opportunity charging could result in the easier implementation of electric buses within public transportation since it solves the range problem that electric vehicles have. The first parts of this paper will provide a discussion about the powertrain model made in Mat- lab/Simulink. The powertrain model input is the driving cycles from the Arnhem Trolleybus data. The outputs are the energy consumption during the driving cycle and the state of charge of the bus battery. The opportunity charger will then be added to the model to analyze the effects of opportunity charging on the bus. The implementation of opportunity charging increases the operational range of the electric bus, while also lowering the energy consumption. The chargers will operate at a high power rating which spans from 100 kW to 200 kW. These power ratings could cause congestion of the grid. This is why the feasibility of PV systems at bus stops is analyzed using a PV model. A PV system is insufficient to power the chargers on its own. The PV system can still provide a significant percentage of the charger power demand.

In this thesis, a custom 120A, 50V power converter board for a brush-less drone motor is designed as part of the Bachelor Graduation Project. The control and embedded systems parts of the project are handled by other subgroups. The power converter consists of three main parts: the inverter, the sensors and the low voltage DC to DC converters. These were implemented respectively with a triple half bridge controlled by high-/low-side gate drivers, analog current en voltage sensors, a digital temperature sensor, buck converters and an LDO. This thesis describes the design choices made for these parts and the development of a PCB temperature model. Two prototypes have been assembled and tested, showing the power converter works as intended. High voltage and current tests are still to be performed to ensure perfect operation. The temperature model yields figures that are high but realistic and the required active cooling has not been quantified. As a final note, the fully integrated ESC was able to make the motor spin at low speeds.

This thesis is part of a project where a 120A, 50V (12S Lithium-Polymer battery) electronic speed controller (ESC) with Bidirectional DShot600 support is prototyped. This thesis focuses on the communication and sensing aspects
of the ESC. It discusses the implementation of the DShot communication protocol on an STM32G431KBT6 microcontroller. Also, the microcontroller senses phase currents and phase voltages from a BLDC motor and has to provide all the necessary information and processing resources for a control algorithm to be implemented. A PCB is designed to break out all the required interfaces of the microcontroller. Lastly, temperature management is implemented to prevent overheating of the inverter hardware by means of throttling. The DShot implementation has full bidirectional functionality with 3.4% package corruption. All sensor values are accurately provided to the control algorithm, and temperature and speed information are provided as DShot telemetry. Due to time constraints and lack of integration with the control algorithm, the behavior during anomalies such as power interrupts is not yet thoroughly tested.

This thesis focuses on finding a control algorithm that, based on a list of requirements, is most suitable for driving the 25 A permanent magnet synchronous motor and propeller that are provided by Fusion Engineering. Various control algorithms are investigated, and basic implementations are simulated. Based on the investigation, it was decided to further optimize the implementation for trapezoidal control and field oriented control. These two algorithms were benchmarked, in order to determine which is more in line with the requirements. This thesis proposes an implementation for a trapezoidal controller that meets most of the requirements.

With the adoption of Wide Band-gap (WBG) switches in Integrated Modular Motor Drives (IMMDs), the size of the drive is rapidly reduced with increase in efficiency and thermal performance. But with the advantages, use of WBG switches as a direct replacement for Si IGBT/MOSFET in Voltage Source Inverter (VSI) posses challenges in the field of steep dv /dt which leads to problems like over-voltage at motor terminal, degradation of cable and motor insulation leading to bearing current and EMI problems.
Current Source Inverter (CSI) mitigates the problems associated with WBG usage in VSI but involves additional components like series SiC diodes leading to additional losses and temperature. This thesis explores design of VSI and CSI topology for High Speed Permanent Motor (HiSPEM) IMMD applications conducts bench-marking study of VSI an CSI based on efficiency and thermal performance of converters. .
To begin with, VSI topology for IMMD modelled in PLECS with designing of control strategy. The loss model of SiC MOSFET used in VSI is simulated along with a lookup-table loss model for fast thermal performance evaluation. The current response is verified with the experimental setup with the comparison of loss model and thermal model results.
Subsequently, the CSI topology is modelled with designing of multi-loop control strategy. The decoupling of the D and Q axis is performed using feed-forward decoupling method. The calculation of output capacitor filter is performed based on the cutoff frequency. The stability and bandwidth of different controller in the multi-loop are evaluated using bode plot analysis. Later, the diode loss is modelled and a thermal model is constructed using loss lookup-table for both SiC MOSFETs and series SiC didoes.
The VSI and CSI typologies are bench-marked against each other on parameters such as converter loss, efficiency and thermal performance revealing the optimum topology to use at different current ratings and switching frequencies.

With the popularity of electrical vehicles (EVs), the demand for EVs charging is also increasing. Compared to traditional wired charging, wireless charging can avoid many safety issues. The efficiency of wireless power transfer (WPT) system is determined by many factors, the coupling factor is one of the most important factors. Therefore, estimating the coupling factor of WPT system is necessary. The research objectives of this work are to review and benchmark different methodologies of coupling factor estimation. Besides, a comprehensive method is selected and simulated. This work is focused on magnetic inductive WPT systems. Five different methodologies of coupling factor estimation for static WPT system and one methodology for dynamic WPT system is reviewed and analyzed. The methodology that uses alternative capacitors to estimate the coupling factor of a static WPT system is analyzed in detail. By using the zero crossing unit, the primary side and secondary side of WPT system are under full resonant. The WPT system will work in two different modes by changing the primary side capacitance. The two sets of circuit parameters will be recorded and calculated by a PLL unit. Based on theoretical analysis and the calculated parameter, the load and mutual inductance of WPT system can be identified. Therefore, the value of the coupling factor can be determined. The accuracy of coupling factor estimation of this methodology is higher than 97 %.
Compared to the literature that proposed this methodology, this work made a sensitivity study. The circuit parameters are made to fluctuate in a certain range. The accuracy of estimation of mutual inductance is still higher than 95% when the primary side resistance, secondary side resistance and load fluctuate. However, the system becomes unstable when the primary side capacitance, inductance and secondary side inductance fluctuate. The reason is that when the capacitance and inductance change, the operating frequency will deviate from the resonant frequency. However, the mutual inductance identification unit is not able to detect this deviation. If the deviation of circuit parameters is updated, the accuracy of coupling factor estimation will remain at about 97%.

In recent years, the Wireless Power Transfer (WPT) system has become more and more popular due to its prominent advantages, especially for Electrical Vehicle (EV) charging. The WPT systems are required to follow the EV battery charging profiles, thus more and more voltage control methods with distinctive characteristics are proposed and studied. The goal of this thesis report is to conduct a comprehensive benchmark of the front-end voltage control solutions.

This thesis report focuses on the front-end voltage control solutions including the front-end buck converter and the phase shift control based on the primary inverter. Six different front-end voltage control scenarios are designed and compared in terms of system efficiency. There are four scenarios of the front-end buck converters including the single-phase buck converter working in Continuous Conduction Mode (CCM), the single-phase buck converter working in Triangular Current Mode (TCM), the two-phase interleaved buck converter working in CCM and the two-phase interleaved buck converter working in TCM. There are also two scenarios of primary inverter-based phase shift controls including phase shift with and without phase delay. The single-phase buck converter working in TCM has the highest efficiency reaching 95.5% at a light load. The phase shift control scenario with phase delay has the highest efficiency exceeding 96.5% at a heavy load.

Different from previous research on phase shift control, this thesis report conducts an in-depth harmonic analysis and compares the accuracy of harmonics analysis with the accuracy of fundamental wave analysis. The conclusion not only proves that fundamental wave analysis is reliable and accurate enough to calculate the phase shift parameters for the S-S compensation but also improves the calculation accuracy at a light load by harmonics calibration.

The compensation network in wireless power transfer (WPT) system has many functions, including increasing efficiency, providing constant voltage/current output, reducing volt-ampere rating, etc. With the popularity of wireless charging for electric vehicles, more and more compensation topologies with distinctive characteristics are proposed. Therefore, a comprehensive comparison among various com-pensation topologies under rated operating condition is necessary for the selection of compensation topology for WPT. In this thesis, eight compensation topologies are selected for benchmark and com-pared in terms of efficiency, component voltage/current stress, design freedom, misalignment be-haviour, etc. under the rated operating condition set based on SAE J2954 [1] standard. Given the analytical comparison results, the S-S compensation and LCC-S compensation are selected for further analysis and experimental verification.
In the practical design process of the compensation, the voltage/current stress on each compo-nent and the implementation of zero voltage switching (ZVS) on switches are two critical issues to be considered. For the calculation of components’ peak voltage/current, the fundamental-frequency analysis is the most widely used calculation method, which is inaccurate in some inductors’ voltage peak calculation. Therefore, a new resonant inductor voltage peak calculation method is proposed in this thesis, which is proved to be more accurate in both simulation and experiments in S-S and LCC-S compensations. For the implementation of ZVS, few studies have given the calculation method of switching current due to its complexity. In this thesis, a new switching current calculation method for LCC-S compensation is proposed and compared with the existing calculation method. A tuning method for ZVS implementation based on this calculation method is also proposed. Results from simulation and experiments under various operating conditions are provided to verify the accuracy of the newly proposed switching current calculation method. In the experiments, the LCC-S compensation and S-S compensation are compared under different power and input voltages. Experimental results show that the efficiency of LCC-S compensation is higher at low power, because of the lower conduction loss on MOSFETs. However, the efficiency of S-S compensation is higher at high power due to less losses on compensation components.