Master Thesis, Aerospace Motor Controller Power

Saab Countermeasures and Aircraft Systems in Huskvarna

This is a Master Thesis about improving power electronic models in flight actuator producs. Suitable for students interested in power electronics.

Your role

Background

Electro-mechanical actuators are key elements of air- and space crafts. In recent years the concept of more electrical aircraft has pushed the development of electrical actuation systems to substitute hydraulic actuators in a broad range of applications such as flight control, landing gear and brake actuation. When designing electro-mechanical actuators for a flight control system one must take into account a lot of parameters that affect each other in various ways. In an electric actuator designed for primary flight control the performance, bandwidth and electromagnetic interference (EMI/EMC) are important aspects, but also how the system behaves under different conditions such as cold or stalled conditions. One setup of an electrical linear actuator is a 3-phase Permanent Magnet Synchronous Motor (PMSM) together with a ball-screw. The actuator is controlled via a cascaded current, speed and position loop motor controller with power transistors and monitoring logic.

Description of the master thesis

This Master Thesis is about improving our power electronic models of our flight actuator products.

One goal is to characterize our motor control modules so that we get a better understanding of the system and its non-linearity's. Another goal is to increase the bandwidth of our actuator which we believe is partially improved by improved modelling, but also by analyzing the sample times and dead-times of our hardware, which could result in suggested improvements for future updates. The electro-mechanical actuator is located on a flying aircraft and you will be working with real aerospace power electronics.

Today we are using a combination of LTSpice and Matlab/Simscape to create our power electronics models.

Possible approaches/suggestions:

* Study the theory of power electronics, electrical actuators and the existing design
* Design/implement a power electronics model
* Evaluate the Pros/Cons with our simulation software, and propose a way forward
* Characterize submodules of the power electronics boards via real-time measurements
* Evaluate improvements for SW/HW, e.g. changed sample time, optimized current sampling, FPGA solutions





Some previous master theses at Saab related to this area:

* http://www.diva-portal.org/smash/record.jsf?pid=diva2:1065318
* http://kau.diva-portal.org/smash/record.jsf?pid=diva2:1340859
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Your profile

This Master Thesis is suitable for 1-2 students with interest in analog and power electronics and/or control system design.

You are at the end of your technical master education in Engineering Physics, Electrical Engineering, or equivalent, and about to start your Master Thesis work for 30 HP.

What you will be a part of

Business Area Surveillance offers solutions for surveillance, decision support, and detection and protection against different types of threats. Within Surveillance there is a product group called Actuation & Utility that focus on electro-mechanical actuation system and power management systems in aircrafts.

Last application day

31-12-2022



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