Dynamic Torque Control of Brushed DC Motors for Hardware-in-the-Loop Integration
(2023)Department of Automatic Control
- Abstract
- The main goal with the thesis was to design, construct and evaluate a system able to drive and brake a mechanical axis to simulate loads and stored rotational energy - a hardware force simulator. The force simulator was then to be integrated in a existing hardware-in-the-loop testing rig to enhance the mechanical dynamics of door simulations. The force simulator was to be realised using a brushed DC motor and by controlling the motor torque. Controlling the motor torque of a brushed DC motor is achieved by controlling the motor current - and this is mainly what this thesis is about. The thesis explains the foundations of an embedded system capable to control and log the current of a brushed DC motor.
The force simulator consisted of a... (More) - The main goal with the thesis was to design, construct and evaluate a system able to drive and brake a mechanical axis to simulate loads and stored rotational energy - a hardware force simulator. The force simulator was then to be integrated in a existing hardware-in-the-loop testing rig to enhance the mechanical dynamics of door simulations. The force simulator was to be realised using a brushed DC motor and by controlling the motor torque. Controlling the motor torque of a brushed DC motor is achieved by controlling the motor current - and this is mainly what this thesis is about. The thesis explains the foundations of an embedded system capable to control and log the current of a brushed DC motor.
The force simulator consisted of a microcontroller, a motor card, a circuit to measure the inline motor current and a brushed DC motor. The circuit to measure the current was designed and implemented, consisting of a shunt resistor and a current sense amplifier. The shunt was placed in series (inline) with the motor. A software strategy was developed and implemented to deal with noise due to common-mode voltage transients (caused by motor control using PWM). This strategy came with a cost of introducing a measurement delay in the system.
A discrete PI-controller to control the motor current was researched and implemented. An expression to optimal tune the controller based on motor parameters and the sampling period was researched. Current control experiments were conducted but due to a calculation error the PI-controller was very untuned, this compared to the tuned expression. This error was discovered very late in the work and there was no time to redo the experiments. The experiments with the implemented untuned PIcontroller were conducted and a current reference was successfully tracked, however with noise which had an amplitude of approximately 200 mA.
A strategy to record current measurements used in the current control, without missing any samples was successfully developed. It worked by using a double buffer system, filling the buffers utilizing a DMA and then written to a SD card once a buffer was filled. With the main objective to develop the capability to be able to analyze the current control algorithm. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9141974
- author
- Schyllert, Eric
- supervisor
- organization
- year
- 2023
- type
- H3 - Professional qualifications (4 Years - )
- subject
- report number
- TFRT-6220
- other publication id
- 0280-5316
- language
- English
- id
- 9141974
- date added to LUP
- 2023-12-04 15:08:09
- date last changed
- 2023-12-04 15:08:09
@misc{9141974,
abstract = {{The main goal with the thesis was to design, construct and evaluate a system able to drive and brake a mechanical axis to simulate loads and stored rotational energy - a hardware force simulator. The force simulator was then to be integrated in a existing hardware-in-the-loop testing rig to enhance the mechanical dynamics of door simulations. The force simulator was to be realised using a brushed DC motor and by controlling the motor torque. Controlling the motor torque of a brushed DC motor is achieved by controlling the motor current - and this is mainly what this thesis is about. The thesis explains the foundations of an embedded system capable to control and log the current of a brushed DC motor.
The force simulator consisted of a microcontroller, a motor card, a circuit to measure the inline motor current and a brushed DC motor. The circuit to measure the current was designed and implemented, consisting of a shunt resistor and a current sense amplifier. The shunt was placed in series (inline) with the motor. A software strategy was developed and implemented to deal with noise due to common-mode voltage transients (caused by motor control using PWM). This strategy came with a cost of introducing a measurement delay in the system.
A discrete PI-controller to control the motor current was researched and implemented. An expression to optimal tune the controller based on motor parameters and the sampling period was researched. Current control experiments were conducted but due to a calculation error the PI-controller was very untuned, this compared to the tuned expression. This error was discovered very late in the work and there was no time to redo the experiments. The experiments with the implemented untuned PIcontroller were conducted and a current reference was successfully tracked, however with noise which had an amplitude of approximately 200 mA.
A strategy to record current measurements used in the current control, without missing any samples was successfully developed. It worked by using a double buffer system, filling the buffers utilizing a DMA and then written to a SD card once a buffer was filled. With the main objective to develop the capability to be able to analyze the current control algorithm.}},
author = {{Schyllert, Eric}},
language = {{eng}},
note = {{Student Paper}},
title = {{Dynamic Torque Control of Brushed DC Motors for Hardware-in-the-Loop Integration}},
year = {{2023}},
}