Papers by Joonas Talvitie
First large volume characterization of the QIE10/11 custom front-end integrated circuits D. Hare,... more First large volume characterization of the QIE10/11 custom front-end integrated circuits D. Hare, A. Baumbaugh, L. Dal Monte et al.-MPPC photon sensor operational experience in CMS Andreas Künsken and the CMS Collaboration-Recent citations Quality control and beam test of GEM detectors for future upgrades of the CMS muon high rate region at the LHC D. Abbaneo et al-The VFAT3-Comm-Port: a complete communication port for front-end ASICs intended for use within the high luminosity radiation environments of the LHC M. Dabrowski et al
2015 17th European Conference on Power Electronics and Applications (EPE'15 ECCE-Europe), 2015
2015 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, 2015
2015 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, 2015
2015 IEEE Applied Power Electronics Conference and Exposition (APEC), 2015
ABSTRACT The authors show for the first time that acoustic events are related to the failure of t... more ABSTRACT The authors show for the first time that acoustic events are related to the failure of transistors. An experimental setup is presented, that was used to make a sample of 26 insulated gate bipolar transistors (IGBT) to fail. The acoustic events in the transistors were monitored. It was discovered that two distinct types of acoustic events are related to the failure. This study complements recent work where it was shown that the switching operation of power transistors causes acoustic emissions to take place.
2014 16th European Conference on Power Electronics and Applications, 2014
ABSTRACT A recent paper showed that the switching operation of a power semiconductor module cause... more ABSTRACT A recent paper showed that the switching operation of a power semiconductor module causes an acoustic emission to take place. In this study, that experiment is repeated using a different kind of acoustic emission sensor. The same conclusion is reached in this stydy as in the previous paper: an acoustic emission takes place as a result of the switching of a power module.
2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC), 2013
ABSTRACT In this paper, the design and implementation of an energy measurement system for an elec... more ABSTRACT In this paper, the design and implementation of an energy measurement system for an electric vehicle competition is described. The system consists of PC-based software and a processor-controlled stand-alone measuring unit with an analog front-end, an SD memory card, a radio link, and a USB interface. The work was carried out as a part of a university project course. The designed system was experimentally tested both in the laboratory and in an actual race.
2013 IEEE International Instrumentation and Measurement Technology Conference (I2MTC), 2013
Modeling the photoelectric response of dry bacteriorhodopsin (bR) sensors has commonly been carri... more Modeling the photoelectric response of dry bacteriorhodopsin (bR) sensors has commonly been carried out by following the theory of linear time-invariant systems. However, it has been reported that the time constants of the photovoltage responses of such sensors vary depending on whether the sensor is measured when the incident light is switched on or off. In this paper, we propose an electrical equivalent circuit for dry bR sensors. Unlike the models presented in the literature, the proposed circuit also considers the illumination on the bR sensor. The model is experimentally verified by photocurrent measurements. Further, a new result concerning the photocurrent dependence on the illumination of dry bR sensors is introduced. I.
2014 16th European Conference on Power Electronics and Applications, 2014
ABSTRACT Electric vehicle competitions have been organized in order to test the limits of technol... more ABSTRACT Electric vehicle competitions have been organized in order to test the limits of technology. In this paper, we describe a competition for students and the public. The competition was held in Lappeenranta in 2013. We also analyze what kinds of vehicles were used and what the winning strategy was.
IEEE Transactions on Power Electronics, 2000
ABSTRACT Traditionally, condition monitoring of power semiconductor modules has been based on ele... more ABSTRACT Traditionally, condition monitoring of power semiconductor modules has been based on electrical measurements. Acoustic emission has been utilized for condition monitoring in many other applications, but is an unknown phenomenon in power semiconductor modules. In this paper the authors present an experimental setup used to show that acoustic emission does occur because of the switching of power semiconductor components. An analysis based on propagation delays is used to determine the source of the acoustic emission.
IEEE Transactions on Industrial Electronics, 2000
ABSTRACT New types of heavy litz wires with noninsulated or insulated strands are offered for hig... more ABSTRACT New types of heavy litz wires with noninsulated or insulated strands are offered for high-power low-voltage electrical machines, where skin and proximity effects can cause serious problems if traditional windings are used. This paper evaluates the ac resistance of a litz wire and its usability in megawatt-range low-voltage electrical machines. The evaluation is made by finite-element analysis and by resistance measurements with an experimental test setup. A simple amplifier configuration was used to minimize current and voltage phase shift errors, which are critical in this kind of low-impedance and low-frequency measurement. A simple measurement device based on the aforementioned configuration was prepared to ensure a precise measurement result. Tests were done in a frequency range of 50-200 Hz, to cover a wide range of practical high-power low-voltage electrical machines. It is found that the measured litz wire with originally noninsulated strands can be used in large electrical machines up to about 120 Hz if about 50% increase in ac resistance compared to the dc resistance is allowed. Impregnation of the originally noninsulated litz wire with vacuum pressure impregnation improved the ac resistance in one test case, and in the other case, it seemed to have no effect on the ac resistance.
2014 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, 2014
ABSTRACT Photoactive biomolecules have been proposed for several technical applications including... more ABSTRACT Photoactive biomolecules have been proposed for several technical applications including optoelectronics. Wild-type bacteriorhodopsin is used as an example molecule to study the photoelectric measurements of dry sensor films and problems related to the implementation and interpretation of the measurement results. Thick bacteriorhodopsin films have high electrical impedance which makes the photoelectric response very sensitive to the loading of the electrical interfaces and the measurement equipment. A measurement circuit featuring a standard instrumentation amplifier was built and connected to a wild-type bacteriorhodopsin sensor for measurements. Our measurements and simulations show how the response shape depends on the sensor-to-instrumentation interface. The results emphasise how the photoelectric response is affected by sensor-amplifier RC time constants and time constants of the instrumentation.
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Papers by Joonas Talvitie