Electric Vehicle Efficient Power and Propulsion Systems

Vehicle electrification has been identified as one of the main technology trends in this second decade of the 21st century. Nearly 10% of global car sales in 2021 were electric, and this figure would be 50% by 2030 to reduce the oil import dependency and transport emissions in line with countries’ climate goals. This book addresses the efficient power and propulsion systems which cover essential topics for research and development on EVs, HEVs and fuel cell electric vehicles (FCEV), including: Energy storage systems (battery, fuel cell, supercapacitors, and their hybrid systems); Power electronics devices and converters; Electric machine drive control, optimization, and design; Energy system advanced management methods Primarily intended for professionals and advanced students who are working on EV/HEV/FCEV power and propulsion systems, this edited book surveys state of the art novel control/optimization techniques for different components, as well as for vehicle as a whole system. New readers may also find valuable information on the structure and methodologies in such an interdisciplinary field. Contributed by experienced authors from different research laboratory around the world, these 11 chapters provide balanced materials from theorical background to methodologies and practical implementation to deal with various issues of this challenging technology. This reprint encourages researchers working in this field to stay actualized on the latest developments on electric vehicle efficient power and propulsion systems, for road and rail, both manned and unmanned vehicles

Graphene field effect transistor based pressure sensors for tactile sensing applications

The development of electronic skin emulating human skin's functionality is a growing area of interest due to its prospect in autonomous and interactive robots, prosthesis and wearable health monitoring devices. In an effort to mimic human skin a number of sensors for the detection of various stimuli have been developed including pressure, strain and thermal sensors. Amongst them, a significant effort has been focused on the development of novel pressure sensors due to their potential in the aforementioned applications. A number of strategies have been adopted for the development of pressure sensors and in particular, there has been a growing interest in the development of field effect transistor (FET) based pressure sensors. This is due to the capability to develop large area high spatial resolution active matrix pressure sensor array. In recent times, there has been a growing demand for the development of flexible pressure sensors due to emerging applications such as smart prosthesis, interactive robots, and wearable electronics. The use of conventional material like Si for flexible electronic applications are limited owing to their rigid and brittle nature. This has led to the investigation of various novel materials like organic semiconductors, carbon nanotube, inorganic semiconductor nanowires, and graphene. Amongst them, graphene is an attractive choice owing to its intrinsic material properties such as its electronic and mechanical properties. Further, the complementary metal oxide semiconductor (CMOS) compatibility and ability to grow high-quality graphene over a large area, and its low optical absorption are some of the other attractive features for the development of large area transparent electronic applications. The high mobility of graphene would enable the development of low voltage devices attractive for flexible electronics applications. This thesis presents work on the development of graphene field effect transistor (GFET) based pressure sensors for tactile sensing applications. The developed sensor comprises of two main components: a top-gate GFET and a piezoelectric transducer layer. A commercially available chemical vapour deposition grown monolayer graphene on Cu foil (from Graphenea) was used as the channel material of the transistor. A high-k Al2O3 deposited by atomic layer deposition technique was employed as the top-gate dielectric. In particular, care was taken to ensure a low temperature CMOS compatible process was adopted for the development of GFET. This ensured that the developed fabrication process could be transferred directly for the development of flexible devices. The development of the transfer process, the impact of different polymers (used as supporting layer during the transfer process) on graphene and the optimisation of dielectric deposition process are discussed in the thesis. The piezoelectric transducer layer is another vital component of the developed pressure sensor. In this respect, two piezoelectric materials, lead zirconate titanate (PZT) and aluminium nitride (AlN), have been investigated as the transducer layer. The pressure sensors were characterised with the piezoelectric transducer layer in an extended-gate configuration with GFET. PZT based pressure sensors exhibited a pressure sensitivity of 4.55E-3/kPa for a pressure range between 0 - 94.18 kPa. Though PZT is a better piezoelectric material than AlN, CMOS process incompatibility, non-biocompatibility and high processing temperature often associated with PZT limit its use in the development of flexible electronics especially for wearable applications. Therefore, AlN deposited by low temperature radio frequency magnetron sputtering has been explored as an alternate piezoelectric transducer layer for pressure sensing applications. The use of AlN also evades the need for the high voltage poling process often employed to enhance the piezoelectric property of the material. The AlN deposited via an optimised RF sputtering process reported in the thesis resulted in film with a piezoelectric constant of 5.9 pC/N. Similar to PZT , AlN was also characterised in an extended gate configuration and exhibited a sensitivity of 7.18 E-3 /kPa for a pressure range of 0-9.74 kPa. In an attempt to improve the spatial sensor resolution of sensor and to improve the signal to noise ratio a piezoelectric layer integrated within the top gate dielectric stack was investigated. In this regard,a flexible GFET with a piezoelectric layer integrated with the top-gate dielectric film was developed. The top gate dielectric stack comprise a 15 nm Al2O3(deposited by ALD)/ 90 nm AlN (deposited by RF sputtering). The developed device exhibited typical GFET electrical characteristics. The electron and hole mobility of the developed devices were 1612 cm2/V.s and 1568 cm2/V.s respectively. In addition, the device also displayed a stable electrical response under mechanical bending condition, thereby demonstrating its potential in the development of flexible electronics

Avoin alustakehitys IEEE 802.15.4 -standardin mukaisessa langattomassa automaatiossa

This doctoral dissertation focuses on open source platform development in wireless automation under IEEE 802.15.4 standard. Research method is empirical. A platform based approach, which targets to the design of a generic open source sensor platform, was selected as a design method. The design targets were further focused by interviewing the experts from the academia and industry. Generic and modular sensor platform, the UWASA Node, was developed as an outcome of this process. Based on the implementation results, a wireless sensor and actuator network based on the UWASA Node was a feasible solution for many types of wireless automation applications. It was also possible to interface it with the other parts of the system. The targeted level of sensor platform genericity was achieved. However, it was also observed that the achieved level of genericity increased the software complexity. The development of commercial sensor platforms, which support IEEE 802.15.4 sensor networking, has narrowed down the role of open source sensor platforms, but they are not disappearing. Commercial software is usually closed and connected to a specified platform, which makes it unsuitable for research and development work. Even though there exits many commercial WSN solutions and the market expectations in this area are high, there is still a lot of work to do before the visions about Internet of Things (IoT) are fulfilled, especially in the context of distributed and locally centralized operations in the network. In terms of control engineering, one of the main research issues is to figure out how the well-known control techniques may be applied in wireless automation where WSN is part of the automation system. Open source platforms offer an important tool in this research and development work.Tämä väitöskirja käsittelee avointa alustakehitystä IEEE 802.15.4 -standardin mukaisessa langattomassa automaatiossa. Tutkimusmenetelmä on empiirinen. Työssä sovelletaan alustaperustaista suunnittelutapaa, joka tähtää yleiskäyttöisen avoimen anturialustan kehittämiseen. Suunnittelun tavoitteita tarkennettiin haastattelemalla alan asiantuntijoita teollisuudesta ja yliopistomaailmasta. Tuloksena suunniteltiin ja toteutettiin anturialusta, the UWASA Node. Implementointituloksista voidaan vetää johtopäätös, että anturialustan tavoiteltu yleiskäyttöisyystaso saavutettiin. Toisaalta saavutettu yleiskäyttöisyystaso lisäsi alustan ohjelmistoarkkitehtuurin monimutkaisuutta. Kaupallisten IEEE 802.15.4 -standardia tukevien anturialustojen tulo markkinoille vähentää avointen anturialustojen käyttöä, mutta ne eivät ole katoamassa. Kaupalliset ohjelmistot ovat tyypillisesti suljettuja ja sidoksissa tiettyyn alustaan, mikä tekee niistä sopimattomia tutkimus- ja tuotekehityskäyttöön. Vaikka nykyään on saatavilla useita kaupallisia langattomia anturi- ja toimilaiteverkkoja, vaaditaan vielä paljon työtä ennen kun kaikki esineiden Internetiin (Internet of Things) liittyvät visiot voidaan toteuttaa. Tämä koskee erityisesti langattomassa anturi- ja toimilaiteverkossa hajautetusti tai paikallisesti toteutettavia toimintoja. Säätötekniikan näkökulmasta keskeinen kysymys on, miten tunnettuja säätömenetelmiä tulee soveltaa langattomassa automaatiossa, jossa langaton anturi- ja toimilaiteverkko on osa automaatiojärjestelmää. Avoimet anturialustat ovat tärkeä työkalu sen selvittämisessä.fi=vertaisarvioitu|en=peerReviewed