Extensive Review on Laminated Bus Bar for Low and High Power Applications

This paper explains about wide range of applications for Laminated Bus Bar used for high and low power applications. Authors also explains ways to effective utilize laminated bus bar when compared to conventional bus bar. Laminated bus bars are designed with low stray inductance and high capacitance with a uniform current distribution in conducting plate. Parameters like Length, Width, material thickness and other miscellaneous parameters effect Laminated bus bar performance. With a proper design of Laminated bus bar it can best utilized, laminated bus bar are suitable for many low and high power applications which are discussed in this paper. Replacing conventional bus bar with laminated bus bar additional advantages are achieved like lighter weight, less space and lower maintenance

Modeling and Optimization Algorithm for SiC-based Three-phase Motor Drive System

More electric aircraft (MEA) and electrified aircraft propulsion (EAP) becomes the important topics in the area of transportation electrifications, expecting remarkable environmental and economic benefits. However, they bring the urgent challenges for the power electronics design since the new power architecture in the electrified aircraft requires many benchmark designs and comparisons. Also, a large number of power electronics converter designs with different specifications and system-level configurations need to be conducted in MEA and EAP, which demands huge design efforts and costs. Moreover, the long debugging and testing process increases the time to market because of gaps between the paper design and implementation. To address these issues, this dissertation covers the modeling and optimization algorithms for SiC-based three-phase motor drive systems in aviation applications. The improved models can help reduce the gaps between the paper design and implementation, and the implemented optimization algorithms can reduce the required execution time of the design program. The models related to magnetic core based inductors, geometry layouts, switching behaviors, device loss, and cooling design have been explored and improved, and several modeling techniques like analytical, numerical, and curve-fitting methods are applied. With the developed models, more physics characteristics of power electronics components are incorporated, and the design accuracy can be improved. To improve the design efficiency and to reduce the design time, optimization schemes for the filter design, device selection combined with cooling design, and system-level optimization are studied and implemented. For filter design, two optimization schemes including Ap based weight prediction and particle swarm optimization are adopted to reduce searching efforts. For device selection and related cooling design, a design iteration considering practical layouts and switching speed is proposed. For system-level optimization, the design algorithm enables the evaluation of different topologies, modulation schemes, switching frequencies, filter configurations, cooling methods, and paralleled converter structure. To reduce the execution time of system-level optimization, a switching function based simulation and waveform synthesis method are adopted. Furthermore, combined with the concept of design automation, software integrated with the developed models, optimization algorithms, and simulations is developed to enable visualization of the design configurations, database management, and design results

Converter- and Module-level Packaging for High Power Density and High Efficiency Power Conversion

Advancements in the converter- and module-level packaging will be the key for the development of the emerging high-power, high power-density, high-eciency power conversion applications, such as traction, shipboards, more-electric-aircraft, and locomotive. Wide bandgap (WBG) devices such as silicon carbide (SiC) MOSFET attract much attention in these applications for their fast switching speeds, resulting in low loss and a consequent possibility for high switching frequency to increase the power density. However, for high-current, high power implementations, WBG devices are still available in small die sizes. Multiple SiC devices need to be connected in parallel to replace a large IGBT die. It is challenging to realize high-switching-frequency and low loss with a lot of parallel devices due to the inherent parameter dierences, which lead to unbalanced dynamic current sharing resulting in unequal temperature distribution and overstress. Apart from the technical challenges, the price of SiC modules is another roadblock for its widespread application. The paralleling of a large number of SiC chips in the module to handle high current increases the module cost. Hence, this work proposes a Si-IGBT and SiC-MOSFET-based hybrid switch solution. For a converter-level packaging, the device technology, available device package, and orientation of the pins are the essential governing factors. This work addresses the converter-level packaging, which is referred to as a power electronics building block, of the proposed hybrid switch, combining discrete packages and frame-based modules for the devices and a singlephase three-level T-type topology. The primary optimization objective for converter-level packaging includes low inductance busbar design, high eciency, and high specic and volumetric power density. Overall implementation is not trivial; however, this work achieves an optimum design compared to the state-of-the-art. The module-level packaging challenges are dependent on the type of device technology and topology. Reducing the parasitic inductances, capacitances, and the junction to case thermal resistance are the optimization objectives in module packaging. Given the intended application of the module, achieving a high-reliability module is also essential. This work includes a hybrid switch-based power module addressing the challenges of WBG module-level packaging and challenges specic to the hybrid switch. The availability of engineering samples of SiC MOSFETs with voltage ratings above 10 kV and commercialization in the future drive the module-level packaging of high voltage devices. High voltage power modules will support the development of future solid-state circuit breakers, transformers, and power conversion applications in shipboards and rolling stocks. The availability of these modules can eliminate the necessity of multilevel topologies. This work investigates and demonstrates the module-level packaging of HV (10-15 kV) SiC MOSFETs

Extensive review on Laminated bus bar for low and high power applications

This paper explains about wide range of applications for Laminated Bus Bar used for high and low power applications. Authors also explains ways to effective utilize laminated bus bar when compared to conventional bus bar. Laminated bus bars are designed with low stray inductance and high capacitance with a uniform current distribution in conducting plate. Parameters like Length, Width, material thickness and other miscellaneous parameters effect Laminated bus bar performance. With a proper design of Laminated bus bar it can best utilized, laminated bus bar are suitable for many low and high power applications which are discussed in this paper. Replacing conventional bus bar with laminated bus bar additional advantages are achieved like lighter weight, less space and lower maintenance

High Power, Medium Frequency, and Medium Voltage Transformer Design and Implementation

Many industrial applications that require high-power and high-voltage DC-DC conversion are emerging. Space-borne and off-shore wind farms, fleet fast electric vehicle charging stations, large data centers, and smart distribution systems are among the applications. Solid State Transformer (SST) is a promising concept for addressing these emerging applications. It replaces the traditional Low Frequency Transformer (LFT) while offering many advanced features such as VAR compensation, voltage regulation, fault isolation, and DC connectivity. Many technical challenges related to high voltage stress, efficiency, reliability, protection, and insulation must be addressed before the technology is ready for commercial deployment. Among the major challenges in the construction of SSTs are the strategies for connecting to Medium Voltage (MV) level. This issue has primarily been addressed by synthesizing multicellular SST concepts based on modules rated for a fraction of the total MV side voltage and connecting these modules in series at the input side. Silicon Carbide (SiC) semiconductor development enables the fabrication of power semiconductor devices with high blocking voltage capabilities while achieving superior switching and conduction performances. When compared to modular lower voltage converters, these higher voltage semiconductors enable the construction of single-cell SSTs by avoiding the series connection of several modules, resulting in simple, reliable, lighter mass, more power dense, higher efficiency, and cost effective converter structures. This dissertation proposes a solution to this major issue. The proposed work focuses on the development of a dual active bridge with high power, medium voltage, and medium frequency control. This architecture addresses the shortcomings of existing modular systems by providing a more power dense, cost-effective, and efficient solution. For the first time, this topology is investigated on a 700kW system connected to a 13kVdc input to generate 7.2kVdc at the output. The use of 10kV SiC modules and gate drivers in an active neutral point clamped to two level dual active bridge converter is investigated. A special emphasis will be placed on a comprehensive transformer design that employs a multi-physics approach that addresses all magnetic, electrical, insulation, and thermal aspects. The transformer is designed and tested to ensure the system’s viability

Design of a 350 kW Silicon Carbide Based 3-phase Inverter with Ultra-Low Parasitic Inductance

The objective of this thesis is to present a design for a low parasitic inductance, high power density 3-phase inverter using silicon-carbide power modules for traction application in the electric vehicles with a power rating of 350 kW. With the market share of electric vehicles continuing to grow, there is a great opportunity for wide bandgap semiconductors such as silicon carbide (SiC) to improve the efficiency and size of the motor drives in these applications. In order to accomplish this goal, careful design and selection of each component in the system for optimum performance from an electrical, mechanical, and thermal standpoint. At each level from top to bottom the inverter sub-assembly performance will be characterized including DC link inductance, power module switching losses, and inverter efficiency. The core power electronics will be built around the latest generation of 1200 V half-bridge SiC power modules with an ultra-low inductance dc bus capacitor and laminated bussing, fast switching speed and very low loss. A custom controller and gate drivers are designed capable of driving the power electronics at high switching speed without disturbance from high dv/dt noise. Finally, the inverter is packaged into a complete system and tested under various conditions with a 3-phase inductive load simulating a motor load. The test results presented include output power and efficiency at various bus voltages, currents, and switching frequencies

High-density And High-efficiency Soft Switching Modular Bi-directional Dc-dc Converter For Hybrid Electric Vehicles

This dissertation1 presents the design of a high-density and high-efficiency soft-switching bi-directional DC-DC converter for hybrid-electric vehicles. The converter operates in a new bidirectional interleaved variable-frequency quasi-square-wave (QSW) mode, which enables high efficiency, high switching frequency, and high power-density. The converter presented utilizes a new variable frequency interleaving approach which allows for each module to operate in an interleaved position while allowing for tolerance in inductance and snubber capacitor values. The variable frequency interleaved soft-switching operation paired with a high-density nanocrystalline inductor and high-density system structure results in a very high performance converter, well exceeding that of the current technology. The developed converter is intended to achieve three specific performance goals: high conversion efficiency, high power density, and operation with 100 °C coolant. Two markedly different converter prototype designs are presented, one converter using evaporative spray cooling to cool the switching devices, with the second converter using a more traditional coldplate design to cool the switching devices. The 200 kW (25 kW per module) prototype converters exhibited power density greater than 8 kilowatts/liter (kW/L), and peak efficiency over 98%, while operating with 100 °C coolan