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This dissertation presents the development of a novel linear magnetostrictive actuator. The magnetostrictive material used here is Terfenol-D, an alloy of the formula Tb0.3Dy0.7Fe1.92. In response to a traveling magnetic field inside the Terfenol-D element, it moves in the opposite direction with a peristaltic motion. The proposed design offers the flexibility to operate the actuator in various configurations including local and conventional three-phase excitation. The conceptual design of the linear magnetostrictive actuator was performed during which different configurations were analyzed. Finite Element Analysis (FEA) was extensively used for magnetic circuit design and analysis in conceptual design. Eventually one of these designs was chosen based on which detailed design of linear magnetostrictive actuator was carried out. A new force transmission assembly incorporates spring washers to avoid the wear due to the sudden collision of Terfenol-D element with the force transmission assembly. All mechanical parts were then fabricated at the mechanical engineering machine shop. The power electronics to operate the motor in a local three-phase mode was designed and implemented. It was demonstrated that the power consumption can be reduced significantly by operating the magnetostrictive linear actuator in the local excitation mode. A finite-element model of the actuator was developed using ATILA and an empirical model was presented using the data gathered from numerous tests performed on the actuator. The closed-loop control system was implemented using relay control which resulted in an optimal closed-loop performance. The magnetostrictive actuator has demonstrated 410-N load capacity with a travel range of 45 mm, and the maximum speed is 9 mm/min. The maximum power consumption by the motor is 95 W. The sensorless control of the linear magnetostrictive actuator was successfully conducted using two different approaches. First, using a linear-approximation method, we achieved a position estimation capability with ±1 mm error. Then, an adaptive neuro-fuzzy inference system was employed for estimating the position which resulted in a position estimation capability with only a ±0.5 mm error.

The switched reluctance motor (SRM) is receiving attention because of its merits: high operating temperature capability, fault tolerance, inherent shoot-through preventing inverter topology, high power density, high speed operation, and small rotor inertia. Rotor position information plays a critical role in the control of the SRM. Conventionally, separate position sensors, are used to obtain this information. Position sensors add complexity and cost to the control system and reduce its reliability and flexibility. In order to overcome the drawbacks of position sensors, this dissertation proposed and investigated a position sensorless control system that meets the needs of an electric actuator application. It is capable of working from zero to high speeds. In the control system, two different control strategies are proposed, one for low speeds and one for high speeds. Each strategy utilizes a state observer to estimate rotor position and speed and is capable of 4 quadrant operation. In the low speed strategy a Luenberger observer, which has been named the inductance profile demodulator based observer, is used where a pulse voltage is applied to the SRMs idle phases generating triangle shaped phase currents. The amplitude of the phase current is modulated by the SRMs inductance. The current is demodulated and combined with the output of a state observer to produce an error input to the observer so that the observer will track the actual SRM rotor position. The strategy can determine the SRMs rotor position at standstill and low speeds with torques up to rated torque. Another observer, named the simplified flux model based observer, is used for medium and high speeds. In this case, the flux is computed using the measured current and a simplified flux model. The difference between the computed flux and the measured flux generates an error that is input to the observer so that it will track the actual SRM rotor position. Since the speed ranges of the two control stragegies overlap, the final control system is capable of working from zero to high speed by switching between the two observers according to the estimated speed. The stability and performance of the observers are verified with simulation and experiments.

Modern electric machine drives, particularly three phase permanent magnet machine drive systems represent an indispensable part of high power density products. Such products include; hybrid electric vehicles, large propulsion systems, and automation products. Reliability and cost of these products are directly related to the reliability and cost of these systems. The compatibility of the electric machine and its drive system for optimal cost and operation has been a large challenge in industrial applications. The main objective of this dissertation is to find a design and control scheme for the best compromise between the reliability and optimality of the electric machine-drive system. The effort presented here is motivated by the need to find new techniques to connect the design and control of electric machines and drive systems. A highly accurate and computationally efficient modeling process was developed to monitor the magnetic, thermal, and electrical aspects of the electric machine in its operational environments. The modeling process was also utilized in the design process in form finite element based optimization process. It was also used in hardware in the loop finite element based optimization process. The modeling process was later employed in the design of a very accurate and highly efficient physics-based customized observers that are required for the fault diagnosis as well the sensorless rotor position estimation. Two test setups with different ratings and topologies were numerically and experimentally tested to verify the effectiveness of the proposed techniques. The modeling process was also employed in the real-time demagnetization control of the machine. Various real-time scenarios were successfully verified. It was shown that this process gives the potential to optimally redefine the assumptions in sizing the permanent magnets of the machine and DC bus voltage of the drive for the worst operating conditions. The mathematical development and stability criteria of the physics-based modeling of the machine, design optimization, and the physics-based fault diagnosis and the physics-based sensorless technique are described in detail. To investigate the performance of the developed design test-bed, software and hardware setups were constructed first. Several topologies of the permanent magnet machine were optimized inside the optimization test-bed. To investigate the performance of the developed sensorless control, a test-bed including a 0.25 (kW) surface mounted permanent magnet synchronous machine example was created. The verification of the proposed technique in a range from medium to very low speed, effectively show the intelligent design capability of the proposed system. Additionally, to investigate the performance of the developed fault diagnosis system, a test-bed including a 0.8 (kW) surface mounted permanent magnet synchronous machine example with trapezoidal back electromotive force was created. The results verify the use of the proposed technique under dynamic eccentricity, DC bus voltage variations, and harmonic loading condition make the system an ideal case for propulsion systems.

The thesis deals in the control of the BLDC motor. At first, there is a brief introduction of BLDC motor, in the next chapters are explained possible methods of control. The next part of the thesis deals with the platform STM32, on which the control algorithm is implemented. For the thesis a program for sensor and sensorless control of BLDC motor has been created. In the conclusion, the process of voltage and current has been measured, using the created algorithm.

The diploma thesis is focused on comparison of sensored and sensorless control of 3phase BLDC motor. This diploma thesis was compiled with engineers from Honeywell, spol. s r. o. and NXP Semiconductors comapny. Theoretical part of the diploma thesis is describing princip of function BLDC motor and different methods of control. The testing of NXP sensored and sensorless application is done in the practical part. Regarding to the fact, that applications were provided by NXP, furthemore the diploma thesis additionally contains a state machine using sensorless application from NXP. Finally, the author is evaluating a cooperation with NXP company and he thinks about next possible cooperation.

This diploma thesis is focused on sensorless DC motor control based on its mathematical model. This solution will be used for Honyewell actuators (type ML5410 and N10010/N05010). The aim of this thesis is to find out if there is a possibility to use this type of motor control for future to replace the existing type of motor control using Hall sensor for measuring speed of motor.

The goal of this thesis is to deal with comparison of algorithms in the field of sensorless control of permanent magnet synchronous motor. It is focused mainly on deterministic methods of estimation, verification of their dynamic responses and the influence of parasitic effects. Implementation of selected algortihms on DSP in fractional arithmetic with verification by Processor-in-the-loop method is described in second part. The last part describes use of algorithms on real drive.

This thesis deals with the design and implementation of the electronic speed controller for a BLDC motor that will be used in a quadcopter. The first part of the thesis explains the methods of control and sensorless commutation respectively. The following part describes the design of the hardware controller. The control firmware was programmed and debugged for this controller.

This thesis is focused on the sensorless control of BLDC motor using the Extended Kalman filter. In the first section, process of EKF implementation for estimating rotor speed and electrical angle is described. For this estimation, EKF uses non-linear BLDC motor model and some measurement containing random noise. Second part deals with designing methodology to measure and estimate the quality of BLDC motor sensorless control. Best results were achieved with total current entering power electronics ripple analyzation. In the last section, several BLDC sensorless control algorithms were evaluated.