Sun-Ki Hong

Hoseo University · Department of Digital System and Control Engineering

The open-loop current transducer comprises a magnetic core made of soft magnet material and includes a Hall sensor. Traction motors in applications such as electric vehicles tend to be driven at high speeds. It pushes the inverters to increase the fundamental frequency of the output current above 1 kHz. However, this high frequency current generate...

Vibration and noise data are signal that directly affected by the motor’s mechanical fault. However, the stator current is also affected to some extent. A deep learning can classify little changes. In other words, the current is classifiable. When using XAI (eXplainable A.I) which outputs the data effect of the trained model, it is available to kno...

- The motor mechanical fault has been diagnosed under fixed driving conditions. The induction motor speed is affected not only by the input frequency but also by the load. In addition, the vibration generated by the induction motor is affected by the speed as well as the input frequency. For these reasons, a data preprocessing algorithm has been de...

Lots of motors have been being used in industry. Therefore many studies have been carried out about the failure diagnosis of motors. In this paper, a diagnosis of gear fault connected to a motor shaft is studied. The fault diagnosis is executed through the comparison of normal gear and abnormal gear. In the abnormal gearbox, a tooth of the intermed...

In this paper, hysteresis voltage control method is proposed to an unidirectional inverter control for piezoelectric load. Piezoelectric load has electrically RC characteristic, and is driven by the inverter to control the output voltage waveform. When controling the output waveform by PI control, appropriate gains need to be selected. However, hys...

3-phase Induction machines are being used in industry and dq transformation from 3 phase of a, b, c is commonly used to analyze these machines. The equivalent circuits of d and q axis are however generally cross coupled and not simple to analyze. In this study, an analysis method of 3ph induction motor considering current regulator using dq transfo...

Common R or R-L load do not need special inverter circuits, however piezoelectric load can be considered as R-C load and its voltage does not become 0 even though the applied voltage is 0. Therefore it needs some special inverter with circuit that can discharge the capacitive energy. Especially for unidirectional square-wave voltage driving, it bec...

AC machines are being used in industry and dq transformation from 3 phase of a, b, c is commonly used to analyze these machines. The equivalent circuits of d and q axis are however generally cross coupled and not simple to analyze. In this study, a modeling technique of AC machine including induction and synchronous motors using matrix vector is pr...

AC machines are in wide use in industry and d-q transformation from 3 phase of a, b, c is commonly used to analyze these kinds of machines. The equivalent circuits of d and q axis are, however, generally cross coupled and difficult to analyze. In this study, a modeling technique of AC machine including induction and PM synchronous motors using matr...

Piezo devices have large power density and simple structure compared with conventional electrical motors. Thus they can generate larger forces than the conventional actuators with small size. Their resopnses to commands are also very fast and thus the bandwidths are very wide. Thus the piezo devices are expected to be used widely in the future for...

Piezo devices have large power density and simple structure. They can generate larger force than the conventional actuators. It has also wide bandwidth with fast response in a compact size. Thus the piezo devices are expected to be used widely in the future for small actuators with fast response time and large actuating force. However, the piezo ac...

Three-phase voltage and current is applied to the three-phase alternating current motors which are commonly used in industry. Three phase variables of a, b, c are converted into d, q, 0 axis and the AC machines are modeled and analyzed. Basically the coordinate transformation or d-q transformation is used for convenience, a few steps are needed to...

Hysteresis current regulator has been used widely because of its simple principle and structure. However, when the current band width is too narrow or the applied voltage is relatively too high, the switching frequency may increase abruptly and it generates a large amount of heat. Thus, this study will suggest a better and simple method to reduce t...

Small permanent magnet generator can be used not only as an emergency power source but also an exciting power source of generator for small generating systems because it does not need the external exciting power source. Especially the air-gap flux density of the buried PM synchronous generator can be increased more than that of the permanent magnet...

Scanning head has used to detect the error signal in register controller. However the resolution of the system is not enough for E-printing(Electronic-paper printing). In this paper, the register mark shapes and process techniques are studied using a smart camera which can detect the register mark and calculate the printing error. With these, a reg...

It is required to analyze the characteristics of inverter-fed induction motor according to the increase of inverter uses. However the previous simulation researches usually uses simplified induction motor model and fixed power source because the difficulties of their modeling and analysis. In this study, high frequency induction motor is simulated...

In this paper, the nature of iron loss in electrical steel during alternating field excitation is investigated more precisely. The exact definition of AC iron loss is cleared by accurately measuring the iron loss for conditions of both the sinusoidal magnetic field and sinusoidal magnetic flux density. The results of this approach to iron loss calc...

The shape of the register mark for the image processing becomes very important, because the printing quality is determined by the error correction between the register marks for the image processing. In this paper, printing marks are developed using the image process for the gravure printing method which is commonly being used in roll to roll, high...

Hysteresis current regulator has been used widely because of its simple principle and structure. However, when the current band width is too narrow or the applied voltage is relatively too high, the switching frequency increases abruptly and it generates a large amount of heat. Thus, this study will suggest a better and simple method to reduce the...

Hysteresis current regulator has been used widely because of its simple principle and structure. However, when the current band width is too narrow or the applied voltage is relatively too high, the switching frequency increases abruptly and it makes large amount of heat. In this study, for single phase current control, the hysteresis current contr...

For Preisach model, Everett function from the transient curves is needed to simulate the hysteresis phenomena. However it becomes very difficult to get the function if the it would be made only from experiments. In this paper, a simple and stable procedure using least square method and logarithm function to determine the Everett function which foll...

The free-piston engine system uses a linear motion of the piston. And the free-piston engine system can guarantee a high efficiency and reliability in the energy conversion process because of the absence of the mechanical motion conversion devices like a crankshaft, a connecting rod, etc. The mover of linear generator move using electric force in t...

This paper presents the thickness effect of hysteresis ring of hysteresis motor using finite element method combined with a vector hysteresis model. From the magnitude and direction of the magnetic field intensity, the magnetization of each ring element is calculated by a vector hysteresis model. The developed torque can be obtained with the vector...

Brushless DC motor is a motor which is modified form DC brush motor and it does not have brushes. BLDCM is easy to centre, has wide speed range, high efficiency. However it needs speed sensor like encoder which increases the motor price and cause some faults in poor surroundings.. In this paper, for the sensorless control, the driving techniques fo...

In this paper, an axial type brushless DC motor which has double rotors using rare-earth magnet pieces is designed. This kind of motor has shorter axial length and is easier to assemble than the radial type motors. To get enough torque, NdFeB magnet is used and for the cost of production, the magnets are segmented to rectangle or disk shape. To des...

Size optimization of steel-cored permanent magnet linear synchronous motor (PMLSM) using auto-tuning niching genetic algorithm (GA) is executed for realizing rapid and smooth driving on the short reciprocating trajectory. Particularly, the dynamic constraints are newly proposed and applied for considering the running conditions of PMLSM. Furthermor...

Design characteristics of steel-cored PMLSM (Permanent Magnet Linear Synchronous Motor) considering the running condition for short reciprocating travel displacements are presented. Particularly, dynamic constraints resulted from repeated short-stroke travel are applied to the design criteria determining the machine specification. In addition, dist...

This paper presents how to determine the thickness of the hysteresis ring of hysteresis motor using the finite element method combined with a vector hysteresis model. From the magnitude and direction of the magnetic field intensity, the magnetization of each ring element is calculated by the vector hysteresis model and the torque can be obtained fr...

In this paper, finite element analysis (FEA) of a hysteresis motor using a magnetization-dependent model is presented. The hysteresis loop in the hysteresis ring is calculated from the maximum flux density which is obtained by the FEA. The proposed method is applied to a sample motor and the simulation result shows a very good agreement with the ex...

Most magnetic materials have nonlinear hysteresis phenomena. In this paper, the efficient combination of the finite element method with a hysteresis model is presented. A magnetization-dependent model is employed as a hysteresis model. Finite element formulation is derived from the modified constitutive equation. This method removes the additional...

A numerical algorithm is developed to predict the distribution of the remnant magnetic flux density in the capacitor-discharge pulse magnetizer by combining the finite element method and the magnetization-dependent Preisach model. After computing the magnetic field by using the finite element method, magnetization-dependent Preisach model is used t...

A numerical algorithm is developed to predict the distribution of the remnant magnetic flux density in the capacitor-discharge pulse magnetizer by combining the finite element method and the magnetization-dependent Preisach model. After computing the magnetic field by using the finite element method, magnetization-dependent Preisach model is used t...

The Preisach model needs a distribution function or Everett function to simulate the hysteresis phenomena. To obtain these functions, many experimental data obtained from the first order transition curves are required. In this paper, a simple procedure to determine the Everett function analytically using the Gaussian distribution function and least...

This paper presents a finite element analysis procedure combined with a vector hysteresis model for the accurate analysis of an hysteresis motor. The vector magnetization-dependent model is adopted to calculate the vector magnetization of the hysteresis ring. From the magnitude and direction of the magnetic field intensity, the magnetization of eac...

This paper presents a method which combines the finite element method with the magnetization-dependent Preisach model for analyzing the hysteresis motor. The proposed method is applied to a sample motor. From the obtained results, it is found that the output torque of the rotor can be estimated by considering harmonic effects due to slot and windin...

A new method employing the immune algorithm (IA) as the search method for the shape optimization of an electromagnetic device is presented. The method is applied to the shape optimization of a pole face of an electromagnet. For the magnetic field analysis the finite element method is used. It is shown that the proposed method with the IA is very us...

This paper describes an implementation of the static magnetic hysteresis using the finite element method and a vector hysteresis model. The vector hysteresis model which is extended from the magnetization-dependent Preisach model is adopted. The magnetization of each element is calculated for a given history of the rotating field. The lagging angle...

The Preisach model neds a density function or Everett function for the hysterisis operator to simulate the hysteresis phenomena. To obtain the function, many experimental data for the first order transition curves are required. However, it needs so much efforts to measure the curves, especially for the hard magnetic materials. By the way, it is wel...

The Preisach distribution function is determined for a grain-oriented electrical steel sheet using two methods: using hysteresis curves, and inverse algorithm method. The methods are combined with finite element method, and the convergence characteristics are compared

D- and q-axis inductance are expected to have ripple characteristics due to the difference of magnetic saturation level of each axis. In this paper, inductance variation of the interior permanent magnet synchronous motor (IPMSM) is calculated with finite element analysis, and cause of inductance variation is analyzed. Finally the validity of this p...