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Tole Sutikno

Bio: Tole Sutikno is an academic researcher from Universitas Ahmad Dahlan. The author has contributed to research in topics: Direct torque control & Torque. The author has an hindex of 19, co-authored 269 publications receiving 1879 citations. Previous affiliations of Tole Sutikno include Universiti Teknikal Malaysia Melaka & University of Akron.


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TL;DR: This work applied and compared data mining techniques to predict the risk of heart diseases and found decision tree has been able to build a model with greatest accuracy.
Abstract: Heart diseases are among the nation’s leading couse of mortality and moribidity. Data mining teqniques can predict the likelihood of patients getting a heart disease. The purpose of this study is comparison of different data mining algorithm on prediction of heart diseases. This work applied and compared data mining techniques to predict the risk of heart diseases. After feature analysis, models by five algorithms including decision tree (C5.0), neural network, support vector machine (SVM), logistic regression and k-nearest neighborhood (KNN) were developed and validated. C5.0 Decision tree has been able to build a model with greatest accuracy 93.02%, KNN, SVM, Neural network have been 88.37%, 86.05% and 80.23% respectively. Produced results of decision tree can be simply interpretable and applicable; their rules can be understood easily by different clinical practitioner.

102 citations

Journal ArticleDOI
TL;DR: The main benefit of the proposed dynamic overmodulation strategy is its simplicity, since it only requires a minor modification to the conventional DTC-hysteresis-based structure and does not require a space vector modulator.
Abstract: A dynamic overmodulation strategy for fast dynamic torque control in direct torque control (DTC)-hysteresis-based induction machine is proposed. The fastest dynamic torque response with a six-step mode can be achieved in the proposed method by switching only the most optimized voltage vector that produces the largest tangential component to the circular flux locus. This paper also discusses the performance of dynamic torque control in basic DTC in order to justify on how the proposed selected voltage vector results in excellent dynamic torque performance. The main benefit of the proposed method is its simplicity, since it only requires a minor modification to the conventional DTC-hysteresis-based structure and does not require a space vector modulator. To verify the feasibility of the proposed dynamic overmodulation strategy, simulation and experimentation, as well as comparison with the conventional DTC scheme, are carried out. Results showed a significant improvement in the dynamic torque response when compared to the conventional DTC-hysteresis-based method.

89 citations

Journal ArticleDOI
TL;DR: In this article, a brief review of direct torque control (DTC) of induction motors and its implementation for electric vehicle (EV) applications is presented, taking into consideration the vehicle mechanics and aerodynamics of electric vehicles.
Abstract: The first and the most important step in solving the environmental problems created by cars with internal combustion engines is research and development of electric vehicles. Selection of a proper drive and optimal control strategy of electric vehicles are the major factors to obtain optimal energy management in order to extend the running distance per battery charge. This paper presents a brief review of direct torque control (DTC) of induction motors (IM) as well as its implementation for electric vehicle (EV) applications. First, the basic DTC technique based on hysteresis controllers will be introduced, and then an overview of the major problems in a basic DTC scheme will be presented and explained, as well as some efforts for improving the technique. The main section presents a critical review of DTC for EV applications, taking into consideration the vehicle mechanics and aerodynamics of electric vehicles. The review is very important to provide guidelines and insights for future research and development on the DTC of IM drives for sustainable reliability and energy efficient EV applications.

88 citations

Journal ArticleDOI
TL;DR: It is demonstrated that FPGA implementation of DTC drives can achieve excellent performance at high sampling frequency and reduce the torque ripple and improved flux and torque estimations.
Abstract: This paper presents a novel direct torque control (DTC) approach for induction machines, based on an improved torque and stator flux estimator and its implementation using field-programmable gate arrays (FPGA). The DTC performance is significantly improved by the use of FPGA, which can execute the DTC algorithm at higher sampling frequency. This leads to the reduction of the torque ripple and improved flux and torque estimations. The main achievements are: 1) calculating a discrete integration operation of stator flux using backward Euler approach; 2) modifying a so called nonrestoring method in calculating the complicated square root operation in stator flux estimator; 3) introducing a new flux sector determination method; 4) increasing the sampling frequency to 200 kHz such that the digital computation will perform similar to that of the analog operation; and 5) using two's complement fixed-point format approach to minimize calculation errors and the hardware resource usage in all operations. The design was achieved in VHDL, based on a Matlab/Simulink simulation model. The Hardware-in-the-Loop method is used to verify the functionality of the FPGA estimator. The simulation results are validated experimentally. Thus, it is demonstrated that FPGA implementation of DTC drives can achieve excellent performance at high sampling frequency.

83 citations

Journal ArticleDOI
TL;DR: In this article, a simple overmodulation method employed in direct torque control (DTC) constant switching frequency (CSF) controller of induction machines was proposed to extend a constant torque region and hence produce high torque capability in field-weakening region with six-step operation.
Abstract: This paper presents a simple overmodulation method employed in direct torque control (DTC) constant switching frequency (CSF) controller of induction machines. The proposed overmodulation method is utilized to extend a constant torque region and hence produce high torque capability in field-weakening region with six-step operation. It will be shown that the overmodulation operation using the DTC-CSF scheme can be established by controlling the stator flux locus from circular to the hexagonal shape. This is achieved by modifying the flux error status produced from the flux hysteresis controller before it is fed to the lookup table. The main benefit of the proposed method is its simplicity since it requires only a minor modification to the conventional DTC hysteresis-based structure and does not require a space-vector modulator.

75 citations


Cited by
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TL;DR: The Brush Foundation studies on human growth and development, begun in 1931 and terminated in 1942, have been intensively reviewed and studied by Dr. Greulich and Miss Pyle in the formulation of this Radiographic Atlas of Skeletal Development of the Hand and Wrist.
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