Past seminars at IEA in 2021

Past seminars in 2021, 2020, 2019, 2018, 2017, 2016, 2015, 2014, 2013, 2012, 2011, 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002, 2001, 2000, 1999, 1998

Back to upcoming seminars

Fredag 3/9 kl 15:30, on Zoom (see below), Presentation av examensarbete.

"Online Parameter Estimation in Electric Motors"

Abizar Sadikot

Permanent magnet synchronous motor (PMSM) operate in different conditions and operating points. It is therefore of interest to check the condition of the motor while it is running. The stator resistance is linked to the temperature of the motor and stator inductance is also of interest to see the condition online. By estimating these parameters, faulty operating points of the motor and critical damage can be stopped. This thesis treats the subject of finding relevant online parameter estimation algorithms and tests them in different simulations. The algorithms researched are; the recursive least square (RLS) with forgetting factor, extended kalman filter (EKF) and the model reference adaptive system (MRAS). They are explained and applied to a non-salient PMSM, meaning that the stator inductance is not dependent on the rotor position. The simulations are done in Matlab/simulink with ten different test cases, emulating different operating points of the motors to see the convergence capability of the algorithms. The thesis also treats the subject of convergence time, and very lightly, the computational complexity of the algorithms.

Handledare: Martin Larsén, Husqvarna Group; Avo Reinap, IEA
Examinator: Francisco J. Márquez-Fernández, IEA

LU Zoom meeting: https://lu-se.zoom.us/j/62398660104
Måndag 21/6 kl 11:00, on Zoom (see below), Presentation av examensarbete.

"Robotic Process Automation in Swedish Healthcare"

Jesper Jonsson

Handledare: Fredrik Wadsten, Triathlon Group; Gunnar Lindstedt, IEA
Examinator: Ulf Jeppsson, IEA

LU Zoom meeting: https://lu-se.zoom.us/j/68230490031 (Waiting room enabled)
Fredag 18/6 kl 13:30, på Zoom, Presentation av examensarbete.

"Model verification and common mode current analysis of grid connected three phase two level converters"

Richard Haraldsson & Simon Lindvall

In grid connected power electronics where switching is used, harmonics are created. High frequency currents are conducted through parasitic elements, such as capacitive, resistive and inductive impedances to the chassi and grid.

In this Master's thesis an in-depth model of a shunt active filter for high frequency analysis is constructed. The purpose is to enable analysis of higher frequency behavior reaching 1MHz. Using the high frequency model, common mode currents can be simulated.

The model is built using high frequency impedance measurements of the internal components in one of Comsys ABs active filters. Using the measured component values and the measured parasitic elements a simulation model could be designed.

This work has been carried out in collaboration with Comsys AB.

Supervisor: Mats Alaküla, IEA
Examiner: Francisco Marquez, IEA
Opponent: Henrik Elmér LU Zoom meeting: https://lu-se.zoom.us/j/61002979186
Tisdag 15/6 kl 10:00, på Zoom, Presentation av examensarbete.

"Mätsystem till test av material för släpkontakt på konduktiva elvägar"

Henrik Elmér

Teknikutveckling för elvägar är högaktuell i dagens samhälle. Flertalet olika tekniker och infrastruktur för laddning under körning av elfordon testas i Sverige idag. En möjlig elvägslösning är laddning konduktivt från ett spår eller skena placerad på vägen under elfordonet. Vid sådan konduktiv laddning släpar en kontakt i spår eller på skena och laddar elfordonet. Detta sätter stora krav på kontaktmaterialet som släpas.

På institutionen för elektroteknik och automation vid Lunds tekniska högskola pågår forskning kring just sådan elvägsteknik. Här finns en testrigg byggd med syftet att testa konduktiv laddning på elväg. I denna rapport beskrivs ett mätsystem som designas och byggs för att testa elektriska kontakter som släpas på denna testrigg. Även begränsade tester på två kontaktmaterial, koppar och aluminium, körs och mäts på testriggen.

Resultatet påvisar ett fungerande mätsystem som i största allmännhet uppfyller kraven som ställs på det. De begränsade materialmätningarna visar några generella samband. De påvisar också några delvis oväntade resultat såsom asymmetrisk uppvärmning av kontakter beroende på elektrisk pol, och effekter på grund av kemiska reaktioner såsom oxidering.

Handledare: Mats Alaküla, IEA. David Wenander, IEA. Philip Abrahamsson, IEA.
Examinator: Francisco Marquez, IEA
Opponenter: Richard Haraldsson, Simon Lindvall

LU Zoom meeting: https://lu-se.zoom.us/j/69503656335
Onsdag 9/6 kl 13:15, M:IEA, Presentation av examensarbete.

"Implementation of RNG and Hardware Test Suite on an FPGA

Oskar Tibblin, Otto Delshammar

Handledare: Kalle Folkesson, Advenica AB; Gunnar Lindstedt IEA
Examinator: Johan Björnstedt, IEA

LU Zoom meeting: https://lu-se.zoom.us/j/62543818813 (Waiting room enabled)
Onsdag 9/6 kl 10:15, on Zoom (see below), Presentation av examensarbete.

"Automated Testing Equipment for Flow Heaters"

Lukas Lundgren, Marcus Daag

Handledare: Hans-Göran Künkel, Andreas Karlsson, Backer AB; Gunnar Lindstedt IEA
Examinator: Johan Björnstedt, IEA

LU Zoom meeting: https://lu-se.zoom.us/j/69241035205 (Waiting room enabled)
Torsdag 3/6 kl 13:15, on Zoom (see below), Presentation av examensarbete.

"Concept study of a new drive system for industrial folding doors"

Johan Möllerström, Patrik Krc Zitny

Handledare: Anders Löfgren, ASSA ABLOY Entrance Systems IDDS AB; Gunnar Lindstedt IEA
Examinator: Johan Björnstedt, IEA

Opponenter: Lukas Lundgren, Marcus Daag

LU Zoom meeting: https://lu-se.zoom.us/j/67113411163 (Waiting room enabled)
3 June 11:00-12:00 in Zoom

"Optimal Control Actions in an Electrical Grid with Variable Renewable Energy Sources - Evaluation of the ANM4L Control Algorithm"

Erik Boman

Supervisors: Olof Samuelsson (LTH), Martin Lundberg (LTH)
Examiner: Morten Hemmingsson

3 June 9:30-10:30 in Zoom:

"Kraftvärme - En förbisedd grundpelare i morgondagens förnybara elsystem"

Truls Martinsson

The work is a collaboration with AFRY and Dept of Energy Science

Supervisors: Olof Samuelsson (LTH)
Examiner: Jens Klingmann (Energy Science, LTH)

1 June 10:00-11:00 in Zoom:

"Monte Carlo Simulations in Load Flow Calculations - An Application on a Swedish 50 kV Network"

Alice Jansson and Emma Åkerman

The work is a collaboration with E.ON Energidistribution.

Supervisors: Olof Samuelsson (LTH), Hampus Möller (E.ON)
Examiner: Morten Hemmingsson

31 May 10:00-11:00 in Zoom:

"Harmonic Emissions in Microgrids - A Case Study of Simris"

Lejla Alibegovic and Emelie Freiland

The work is a collaboration with E.ON Energidistribution.

Supervisors: Olof Samuelsson (LTH), Imran Maqbool (LTH), Neil Hancock (E.ON)
Examiner: Morten Hemmingsson
Opponent: Truls Martinsson

Wednesday 31/3 kl 10:30 Zoom (see below)
Master's thesis presentation

Optimering av sekvenser i produktionsplanering

Erik Kronberg

The work has been carried out at Novotek AB, Malmö.

Supervisors: Jens Molin and Nils Lindqvist, Novotek, Gunnar Lindstedt, IEA
Examinator: Ulf Jeppsson IEA

LU Zoom meeting: https://lu-se.zoom.us/j/67724520037?pwd=S3k2MktUVXhjcGRsSzlxWHlMMUROdz09
Meeting ID: 677 2452 0037
Password: 002390
Monday 29/3 kl 15:15 Zoom (see below)
Master's thesis presentation

Implementering av ett Manufacturing Execution System i en produktionsanläggning

Gabriella Nordquist
Claes Kinch

The work has been carried out at Arvid Nordquist HAB, Solna.

Supervisors: Sophie Tärnström and Kaj Lönnberg, Arvid Nordquist, Gunnar Lindstedt, IEA
Examinator: Johan Björnstedt, IEA

LU Zoom meeting: https://lu-se.zoom.us/j/67571986448
Meeting ID: 675 7198 6448 (Waiting room enabled)
Friday 5/3, 13:00-14:30 Zoom (see below)

Master's thesis presentation

Automated connection for charging of agricultural machines in the field

Henrik Rosberg

Abstract: When it comes to the electrification of agriculture, one of the most challenging problems is the energy supply to the field vehicles (mostly tractors, but also other more specialised machines). These vehicles usually operate in harsh environmental conditions of mud, dust and dirt, in fields that may be several kilometres away from their base. This, together with their high power consumption (depending on the task at hand) and long working passes motivates the need for a portable charging solution that enables charging in the field. In this thesis a concept study is presented, evaluating what type of charging solution is the most appropriate for this. The study takes into consideration static (charging while the vehicle is at standstill at the designated charging station) and dynamic (charging while the vehicle keeps working) charging alternatives are considered, as well as battery swapping. The proposed alternatives are evaluated in terms of robustness, cost effectiveness, efficiency and portability, for different system parameters such as the battery size on board the vehicles, the average power consumption of the vehicles or the maximum field area (in hectares) that can be covered in a day. The results show that static charging is more cost effective than dynamic charging in almost all cases, except when the considered battery cost is higher than 200 USD/kWh and the maximum field area that can be covered in one day is larger than 80 hectares. However, even in this cases, the lower robustness and higher potential investment risks associated with developing a dynamic charging solution may still favour static charging. Based on this, a robust and portable static charging station concept has been developed and is presented in this work.

The work has been carried out in collaboration with Volvo Construction Equipment in Eskilstuna.

Supervisors: Francisco J. Márquez-Fernández (LTH), Bobbie Frank (Volvo CE) and Joakim Unnebäck (Volvo CE)
Examiner: Mats Alaküla.
Opponent: Edvin Wallander and Erik Boman

Link: https://lu-se.zoom.us/j/64501280614

You can also join the meeting by entering the following information in the Join a meeting dialogue or in the Zoom app: Meeting ID: 645 0128 0614 Dial into the meeting with a local number: +46 8 5050 0828 Sweden +46 8 5052 0017 Sweden If your local number is not listed, look it up at: https://lu-se.zoom.us/u/cdpQ7dfhVp
Friday 5/3, 10:30-12:00 Zoom (see below)

Master's thesis presentation

Modelling and Control of Dish-Stirling Solar/Gas Hybrid System

Edvin Wallander

Abstract: The world is moving towards more sustainable energy production, creating pressure and opportunity for the development of renewable energy sources. The new energy system is likely to be built around renewable energy sources like wind and solar, hydrogen and bio-methane. This project will focus on developing a unique concentrated solar power technology (CSP). The system is being developed by the company Stirlingversal and utilizes a Stirling engine, a reflecting dish and a gas burner to be able to generate power even when the sun is not shinning. In this thesis a model of the Dish-Stirling system is developed including a model of the Stirling engine and the generator connected to the grid. A fixed speed squirrel-cage induction generator configuration and a variable speed doubly-fed induction generator configuration are modelled and compared. Power quality improvement methods are implemented in both systems. Lastly an electrolyser is modelled and integrated with the system. Hybrid mode operation is modelled and analysed in terms of gas consumption for different irradiation conditions and the model results are then used to compare the hybrid Dish-Stirling system with a photovoltaic and battery based system of equivalent performance for two potential locations that offer very different solar power potential: Lund (Sweden) and Johannesburg (South Africa). The comparison shows that given a low enough fuel price the Stirling system can be cheaper than a comparable PV and battery based system when electricity generation is considered. However, the Dish-Stirling system needs not only a cheap but also environmentally sound fuel source in order to be competitive.

The work has been carried out in collaboration with Stirlingversal AB.

Supervisors: Francisco J. Márquez-Fernández (LTH), Lars Larsson (Stirlingversal AB), Lars Olsson (Stirlingversal AB)
Examiner: Mats Alaküla.
Opponents: Claes Kinch and Gabriella Nordquist

Link: https://lu-se.zoom.us/j/68039010654

You can also join the meeting by entering the following information in the Join a meeting dialogue or in the Zoom app: Meeting ID: 680 3901 0654 Dial into the meeting with a local number: +46 8 5050 0828 Sweden +46 8 5052 0017 Sweden If your local number is not listed, look it up at: https://lu-se.zoom.us/u/ccF3TgcXnS
26 February 10:30-11:30 in Zoom (see below)

"Study of an automated testing procedure with dynamic job scheduling and automatic error handling"

Tom Andersson

The work has been carried out at Axis Communications.

Supervisors: Bjorn Hansson (Axis), Martin Nyman (Axis), Gunnar Lindstedt (IEA)
Examiner: Ulf Jeppsson
Opponent: Erik Kronberg

LU Zoom meeting: https://lu-se.zoom.us/j/63147165304?pwd=aHA2TElLSDhmTXAyQ3UyQ0NhV2RLQT09

You can also join the meeting by entering the following information in the Join a meeting dialogue or in the Zoom app:
Meeting ID: 631 4716 5304
Password: 145974
28 January 13:15-14:15 in Zoom (see below)

"Energy Storage for Voltage Control in LV Grids - Sizing, Control Strategies and Economic Benefits"

Ida Samnegård

This thesis addresses overvoltage issues in weak low voltage grids caused by large solar power production. The suggested method is using PI controllers to control battery energy storage systems (BESS), designed to absorb active power during these times and thereby limiting the voltage rise. This could enable faster integration of solar power and a reduced demand for network reinforcement. A case study was conducted on a rural part of a grid owned by Kraftringen in southern Sweden. The network was modeled in Simulink with hourly load data from 2017-2020. Furthermore, solar power installations based on solar data from the same time period were added. Required power and energy storage capacity of the BESS needed to keep voltage within acceptable limits were determined, as well as the impact of PV penetration, battery placement and line types on these dimensions. Furthermore, it was investigated during which times the BESS had to be reserved for voltage control, and whether the BESS could be used to provide other services during the remaining time. Results showed that with 30 kW installed solar power at each one of the four customers, a BESS placed at the customer most sensitive to voltage rise required 13 kW/62 kWh battery capacity. The BESS was used about 50 % of the days between mid-April and mid-August and unused the rest of the year. During the days needed, it was used for a maximum of 9 hours per day. This enabled the opportunity to use the BESS for other services such as frequency control during night time and winter, as well as for load and production peak shaving. These additional services could play an important role in making the solution economically viable.

The work has been carried out at Kraftringen.

Supervisors: Olof Samuelsson (LTH), Martin Lundberg (LTH), Håkan Skarrie (Kraftringen).
Examiner: Morten Hemmingsson.
Opponents: Alice Jansson, Emma Åkerman, Lejla Alibegovic, Emelie Freiland

LU Zoom meeting: https://lu-se.zoom.us/j/63028450413?pwd=YXNJWUlSKzVFUEJ5SmE0UWtSL2t5QT09

You can also join the meeting by entering the following information in the Join a meeting dialogue or in the Zoom app:
Meeting ID: 630 2845 0413
Password: 900381
15 January 10:30-11:30 on Zoom (see below).

"Evaluation of a Switched Reluctance Machine in an Automotive Oil Pump Application"

Edvin Malm, August Wahlberg

The goal of the thesis has been to evaluate the Switched Reluctance Machine's (SRM) competitiveness in means of torque quality, cost and driver requirements. The aim has been to give BorgWarner insight into the control methodology and possible applications for a Switched Reluctance Machine as well as comparing it to their current BLDC machine solution. The evaluation and implementation of control methodologies has been done on a 4/2 asymmetric Switched Reluctance Machine.

The following list highlights the most important aspects of the thesis-

- The SRM control has been developed using two different approaches, simulation and experimental measurement of motor characteristics. The two approaches have been evaluated in regard to how well they represent the physical machine.
- Two control methods "Instantaneous Torque Control (ITC)" and "Average Torque Control (ATC)" have been implemented and evaluated in regard to match the BLDC application of a speed controlled oil pump.
- The different control methods ITC and ATC have been compared in regard to torque-speed performance, speed ripple and ease of implementation.
- Evaluated sensorless position control in simulation.
- The BLDC motor and the SRM have been compared with respect to cost of motor, cost of driver components and cooling requirements.

The work has been carried out at BorgWarner.

Supervisors: Mats Alaküla (IEA), Markus Björk (BorgWarner), Robin Levenhammar (BorgWarner).
Examiner: Francisco Marquez (IEA)

LU Zoom meeting: https://lu-se.zoom.us/j/65343068207

You can also join the meeting by entering the following information in the Join a meeting dialogue or in the Zoom app.
Meeting ID: 653 4306 8207

Friday 15/1 kl 08:30 Zoom (see below)

Master's thesis presentation

Dynamic Torque Modeling of a Wet Lamella Clutch Pack

Johan Appelros
Jacob Wallersköld

Wet lamella clutches are used in the automotive industry to enable all-wheel drive and thereby increase acceleration, handling and safety of cars. The clutches work by transmitting torque from an incoming- to an outgoing shaft through a series of lamella - steel-disc friction surfaces (lamella pack), lubricated by an oil. Based on temperature and wheel-speed measurements, a mathematical model of the clutch is used by the software to calculate the appropriate actuation of applied pressure to match a desired torque output. The primary goal of the thesis was to identify dynamic behavior of the clutch in order to increase torque accuracy in the torque estimation model. This was done by first analysing previously collected data from tests in rigs and cars and thereby form two hypotheses. Hypothesis 1 was related to spline friction losses within the lamella pack and Hypothesis 2 was related to oil lm reduction and an increase in friction coefficient. In an attempt to prove the hypotheses, rig tests were performed where dynamic torque responses were provoked. A novel measurement technique was introduced comprising of four thin force-measuring sensors being placed at the front and rear lamellas in the pack respectively in an attempt to measure variations of force. As some sensors were damaged during the tests it was not possible to get an absolute measurement of force, but by making relative comparisons as well as motivated assumptions, some indications related towards Hypothesis 1 could be observed. A mathematical model assuming each lamella to be a affected by a spring force, a damping force and a spline friction force acting on its body was suggested. This model was shown to increase torque accuracy on tested data.

The work has been carried out at BorgWarner Sweden AB, Landskrona.

Supervisors: Fredrik Salbrink (BorgWarner), Daniel Blom (BorgWarner) and Anton Karlsson (IEA)
Examinator: Gunnar Lindstedt (IEA)

LU Zoom meeting: https://lu-se.zoom.us/j/64788247549
Meeting ID: 647 8824 7549 (Waiting room enabled)

Past seminars at IEA in previous years
2021, 2020, 2019, 2018, 2017, 2016, 2015, 2014, 2013, 2012, 2011, 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, 2002, 2001, 2000, 1999, 1998