Muhammet Garip

An approach to torque ripple reduction in fully pitched switched reluctance motors by pole tip shaping

Torque ripple is a drawback for both conventional and fully pitched SRM structures. Although there are several publications in the literature addressing the full or partial solution to the problem for conventional SRM, but not for emerging fully pitched SRM. This paper proposes a solution to a torque ripple problem in fully pitched SRM by shaping stator and rotor pole tips. The essence of the proposed method is to shape the inductance profile of the motor so that torque profile changes accordingly. Analysis has been performed with the finite element (FE) model of 6/4 3-phase fully pitched SRM with unipolar excitation. A sharp increase and decrease in torque profile existing before the proposed geometry has been smoothed out after pole tip shaping. This brings the torque ripple level from 37.2% to 13.7% for 6 A phase current.

Investigating Operating Modes and Converter Options of Dual Winding Permanent Magnet Synchronous Machines for Hybrid Electric Vehicles

Summary form only given. This paper investigates the operating modes and converter options of dual winding permanent magnet synchronous machines (DWPMSMs) that are used to drive accessories in hybrid electric vehicles. In this application, DWPMSM operate in three different modes: 1) motor-only; 2) generator-only; and 3) simultaneous motor-generator modes. Motor-only and generator-only operations can be treated independently as long as two winding sets are magnetically decoupled. Simultaneous motor-generator mode links two winding sets through a mechanical shaft. As part of this study, the impact of dual winding set usage on the machines output and performance is also investigated. Experimental results are given for each mode. The converter options of generator winding were investigated as well. These options include uncontrolled rectifier with dc-dc converter and controlled rectifier. Two converters are compared for their impacts on efficiency and generator current harmonics. The relationship between speed and converter control variable is given for various back electromotive force constant values of the DWPMSM.

A new electric accessory drive system for hybrid electric vehicles

This paper presents a new electric accessory drive system for hybrid electric vehicles. The system offers cost and space advantages. In this concept, dual winding electric machine with simultaneous motor and generator functions is used. The electric machine provides power for all accessory loads such as steering pump, compressors, and 12V loads. If the engine is on, accessory loads are driven by engine through a belt like conventional vehicle. If the engine is off, electric machines motoring action starts and provides mechanical power to accessory loads. Simultaneously, the generator windings provide power for 12 V loads. Converter options for generator were also investigated and preliminary experimental results were presented.

An adaptive compensator for a vehicle driven by DC motors

Abstract A vehicle system driven by two independent DC motors is presented here, one of which is used for the right wheel and the other is used for the left wheel. An adaptive compensator using Takagi–Sugeno fuzzy systems is proposed to control the vehicle system. The compensator includes an adaptive model identifier and adaptive controller. An online method is used to adjust the parameters of the identifier model to match the behavior model of the vehicle system. Then, the parameters of the identifier model are employed in a standard parallel-distributed compensator to provide asymptotically stable equilibrium for the closed-loop vehicle drive system, in which the velocity and direction angle of the vehicle are controlled. Results demonstrate that the proposed controller structure is robust to load changes and follows different trajectories very well.

Three-axis gap clearance I-PD controller design based on coefficient diagram method for 4-pole hybrid electromagnet

ABSTRACT 4-pole hybrid electromagnetic systems have a potential usage in many industrial areas, such as clean room design, transportation, semi-conductor manufacturing due to providing mechanical contact-free operation with considerably low energy consumption. However, the main problem of magnetic levitation process: it has highly nonlinear nature and even if it can be linearized, it has unstable pole(s), which makes the system vulnerable in terms of stability. In this paper, to overcome the instability issue and track the desired references for each degree of freedom, a modified PID controller (so called I-PD) design technique based on coefficient diagram method (CDM) has been proposed. CDM is an algebraic design applied to polynomial structure of the system on the parameter space, where a specific diagram is used to present and interpret the essential data. It is quite simple to apply with a visual support, requires basic mathematical computations for field engineers, and offers a good equilibrium in terms of simplicity, stability, minimum overshoot and robustness, which are crucial specifications for maglev applications. The effectiveness and feasibility of CDM-based I-PD controller have been compared with CDM-based classical PID controller over an experimental set-up.

Rocking motion of the baby sleeping on the mother's lap: Modeling and prototype automatic swing cradle design

The main purpose of this study is to overcome the difficulties experienced by the mothers during the sleeping period of the babies and to put the babies to sleep in a comfortable and peaceful way as if the babies were in the mothers lap. In this direction, the motion that the mother made while sleeping her baby on the lap was modeled, and a cradle designed to repeat mother movements based on this model. In the modeling phase, 10 subjects were experimented. A doll was given to the subjects and it was requested that to perform a baby rocking motion on their lap for 10 seconds. I he performed motions of the subjects were recorded with accelerometer of the mobile phone placed on the doll via an application (Accelerometer Analyser) compatible with the Android operating system. From the acceleration data, the motion trajectories of each subject were achieved through MATLAB. For this aim, firstly the noise in the data was filtered with moving average filter and then trapezoidal integration was applied twice to the filtered acceleration data. After that, the ideal route for the rocking motion on the lap was reached in consideration of the trajectories of the subjects. The mathematical model of the ideal route was derived by least square curve fitting method and the cradle following the mathematical model was designed in Solidworks environment. At the end of the study a prototype cradle was produced.

Investigating operating modes and converter options of dual winding permanent magnet synchronous machines for hybrid electric vehicles

This paper investigates the operating modes and converter options of dual winding permanent magnet synchronous machines (DWPMSMs) that are used to drive accessories in hybrid electric vehicles. In this application, DWPMSM operate in three different modes: motor-only; generator-only; and simultaneous motor-generator modes. Motor-only and generator-only operations can be treated independently as long as two winding sets are magnetically decoupled. Simultaneous motor-generator mode links two winding sets through a mechanical shaft. As part of this study, the impact of dual winding set usage on the machines output and performance is also investigated. Experimental results are given for each mode. The converter options of generator winding were investigated as well. These options include uncontrolled rectifier with dc-dc converter and controlled rectifier. Two converters are compared for their impacts on efficiency and generator current harmonics. The relationship between speed and converter control variable is given for various back electromotive force constant values of the DWPMSM.