Master Thesis: Refinement and Validation of the InnoSat State of Charge Estimator
OHB Sweden is a leading provider of space systems, developing, building, testing, and operating satellites and in-orbit propulsion systems for missions in communication, Earth observation, and space research. Serving both institutional and commercial customers across Europe and beyond, OHB Sweden offers an exciting workplace where you can contribute to shaping the future of space technology.
We are now looking for a motivated Master student to carry out their Master thesis with us!
Background and purpose of the master's thesis:
The reliable operation of a satellite depends critically on its power system — and at the heart of that system are its batteries. OHB Sweden’s InnoSat platform uses lithium-ion battery technology to supply power to all spacecraft subsystems during mission phases in which the solar array is not illuminated. Accurately estimating the State of Charge (SoC) of these batteries is essential for mission safety, performance optimization, and lifetime management.
The purpose of this thesis is to revisit, refine, and modernize the InnoSat SoC estimation system, ensuring it is robust, maintainable, and adaptable to new lithium-ion battery technologies with minimal testing and characterization requirements.
Thesis overview:
The goal of this master’s thesis is to analyze, improve, and validate the State of Charge estimator for the InnoSat satellite platform. The work includes understanding the existing algorithm, implementing improved estimation methods, and verifying their performance through simulation and, if applicable, hardware-in-the-loop testing.
The tasks of the master's thesis topic are as follows:
- Analyze the existing SoC estimation algorithm.
- Review battery characterization methods and identify approaches to minimize testing while maintaining accurate SoC estimation.
- Explore and implement improved SoC estimation techniques, possibly including adaptive filters or alternative modeling approaches.
- Validate the estimator performance through simulation and comparison with test data from existing or new battery types.
- Deliver recommendations for a clear, maintainable, and mission-adaptable SoC estimation framework for future InnoSat missions.
The required candidate’s skills are:
- A background in Electrical Engineering, Space Engineering, Control Systems, or a related field.
- Strong knowledge of system modeling, estimation theory, and numerical methods.
- Experience with MATLAB/Simulink, Python, or similar simulation environments.
- Familiarity with battery modeling and filtering techniques is highly advantageous.
- Good understanding of embedded systems and space hardware is a plus.
- Excellent analytical, problem-solving, and communication skills.
What can we offer the students to help them to succeed in their master's thesis:
This master’s thesis offers an opportunity to contribute directly to build a robust and predictable power system for OHB Sweden’s satellite missions. You will gain hands-on experience with real satellite battery data, advanced estimation algorithms, and space-grade embedded systems.
You will work closely with experienced engineers at OHB Sweden, receiving guidance and technical mentorship throughout the project.
Successful completion of the thesis may open opportunities for future employment as a Systems or Power Engineer within OHB Sweden.
We're looking forward to hearing from you! 🛰️
- Department
- Students and Internships
- Role
- Thesis
- Locations
- Kista (Stockholm)
Kista (Stockholm)
Benefits
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Paid days off
In addition to the 25 or 30 days holidays, the offices are closed between Christmas and New Year and on days in between Public Holidays... which are paid days off.
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Company events
Annual Summer and Christmas parties, along with other social events during the year such as BBQs, movie nights, ski trips, build challenges and the nationally mandatory weekly "fika".
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Health promotion
Annual health checks, and we offer Benify's self-portal for sports activites, and 3000 SEK/year in wellness contribution.
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Swedish lessons
Introductory Swedish language courses for those newly relocated to Sweden. In other words, "välkommen till Sverige!"
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On-site amenities
Change rooms, showers, kitchen, terrass, massage, table tennis, yoga mats, bicycle repair station and a nearby nature reserve.
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Flexible working hours
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Personal development
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Fruits, coffee, tea and "fika"
About OHB Sweden
Building its success on the passion and exceptional talent of its employees, its extensive knowledge base, OHB Sweden stands stronger than ever to take on new innovative space missions together with its ever growing network of partners and customers.