Romina Rodriguez

Bio: Romina Rodriguez is an academic researcher from McMaster University. The author has contributed to research in topics: Power electronics & Thermoelectric generator. The author has an hindex of 6, co-authored 19 publications receiving 123 citations. Previous affiliations of Romina Rodriguez include Massachusetts Institute of Technology.

Automotive Power Module Packaging: Current Status and Future Trends

Abstract: Semiconductor power modules are core components of power electronics in electrified vehicles. Packaging technology often has a critical impact on module performance and reliability. This paper presents a comprehensive review of the automotive power module packaging technologies. The first part of this paper discusses the driving factors of packaging technology development. In the second section, the design considerations and a primary design process of module packaging are summarized. Besides, major packaging components, such as semiconductor dies, substrates, and die bonding, are introduced based on the conventional packaging structure. Next, technical details and innovative features of state-of-the-art automotive power modules from major suppliers and original equipment manufacturers are reviewed. Most of these modules have been applied in commercial vehicles. In the fourth part, the system integration concept, printed circuit board embedded packaging, three-dimensional packaging, press pack packaging, and advanced materials are categorized as promising trends for automotive applications. The advantages and drawbacks of these trends are discussed, and it is concluded that a preferable overall performance could be achieved by combining multiple technologies.

Modeling and Analysis of Electric Motors: State-of-the-Art Review

Abstract: This paper presents a comprehensive state-of-the-art review of the modeling and analysis methods for the multidisciplinary design of electric motors for various applications including vehicular power and propulsion systems and electrified powertrains. It covers the important aspects of different engineering domains, such as dynamic modeling, loss calculations, demagnetization analysis, thermal modeling, acoustic noise and vibration analysis, and mechanical stress modeling. This paper intends to guide the electric motor designers through examples and results on how to apply different analysis techniques on electric motors.

Review and Trends of Thermoelectric Generator Heat Recovery in Automotive Applications

Abstract: Automotive vehicles with internal combustion engines, such as conventional gasoline and electric hybrid vehicles, exhibit inherent irreversibilities that hinder them from achieving high efficiencies. These irreversibilities manifest themselves in the form of thermal losses in the engine and contribute to the total energy consumption in the transportation sector. Waste heat recovery is a method to increase the overall fuel efficiency of vehicles by recovering thermal energy that would be lost from the engine to the environment and converting it to useful energy for the vehicle. In the past years, thermoelectric generators have been intensively investigated for waste heat recovery in vehicles because they are solid-state devices that convert heat directly into electricity and hence have no moving parts, operate quietly, are relatively small, and require low maintenance. This paper presents a review of the literature on waste heat recovery in vehicles through the implementation of thermoelectric generators. First, potential sources or locations in a vehicle for waste heat recovery are presented. Second, the available thermoelectric technology for vehicle applications is reviewed. Then, the components required to create a waste heat recovery system are discussed. The approach for modeling thermoelectric generators to predict the power output is then considered. Finally, experimental investigations by researchers are presented as well as the future trends observed for waste recovery via thermoelectrics.

Jet Impingement Cooling in Power Electronics for Electrified Automotive Transportation: Current Status and Future Trends

Abstract: Effective thermal management of power electronics in electric vehicles is essential for reliability and increased power density. Currently, traditional cooling technologies such as cold plates and heat sinks have been utilized by the automotive industry. As the next generation of power electronics implements wide-bandgap devices, however, increased heat fluxes will require more advanced cooling strategies. Recently, jet impingement has gained attention as an advanced cooling technique for power electronics due to its proven thermal performance in high-heat-flux applications. This article aims to review the state-of-the-art jet impingement designs applied for power electronics cooling, as well as review future jet impingement technology. Important factors for widespread implementation such as heat transfer, pressure drop, and reliability are discussed, along with the current technical gaps and challenges for jet impingement research in electrified transportation.

Generalized State Space Average Model for Multi-Phase Interleaved Buck, Boost and Buck-Boost DC-DC Converters: Transient, Steady-State and Switching Dynamics

Abstract: This paper presents a generalized state space average model (GSSAM) for multi-phase interleaved buck, boost and buck-boost converters. The GSSAM can model the switching behavior of the current and voltage waveforms, unlike the conventional average model which can model only the average value. The GSSAM is used for the converters with dominant oscillatory behavior such as resonant converters, high current ripple converters, and multi-converter systems. The maximum current and voltage through the system can be predicted by modeling the switching behavior of voltage and current. The GSSAM in the literature is introduced for single-phase converters only, and it is not introduced for multi-phase converters due to the high complexity associated with it. Hence, the GSSAM for multi-phase buck, boost and buck-boost converters are introduced in this paper and the proposed models can fit with converters of any number of phases. The number of operating phases in the multi-phase interleaved converters is proportional with the output power to achieve the maximum efficiency over the operating range. Therefore, the proposed GSSAMs can describe the operation at any number of operating phases with switching dynamics of phases. The proposed GSSAM is validated by comparing the transient and steady-state dynamics between the GSSAM and a switching model from PLECS.

Health Risk Assessment of Heavy Metal in Urban Surface Soil (Klang District, Malaysia)

Abstract: Urban environmental quality is vital to be investigated as the majority of people live in cities. However, given the continuous urbanization and industrialization in urban areas, heavy metals are continuously emitted into the terrestrial environment and pose a great threat to human. In this study, a total of 76 urban surface soil samples were collected in the Klang district (Malaysia), and analyzed for total and bioavailable heavy metal concentrations by inductively coupled plasma-optical emission spectrometry. Results showed that the concentrations of bioavailable heavy metals declined in the order of Al, Fe, Zn, Cu, Co, Cd, Pb, and Cr, and the concentrations of total heavy metals declined in the order of Fe, Al, Cu, Zn, Pb, Cr, Co, and Cd. Principal component analysis (PCA) showed that heavy metals could be grouped into three principal components, with PC1 containing Al and Fe, PC2 comprising Cd, Co, Cr, and Cu, and PC3 with only Zn. PCA results showed that PC1 may originate from natural sources, whereas PC2 and PC3 most likely originated from anthropogenic sources. Health risk assessment indicated that heavy metal contamination in the Klang district was below the acceptable threshold for carcinogenic and non-carcinogenic risks in adults, but above the acceptable threshold for carcinogenic and non-carcinogenic risks in children.