단상유도전동기의 최적 구동을 위한 디지털 위상각 제어기 설계

박수강,백형래,김평호 조선대학교 에너지.자원신기술연구소 1999 에너지·자원신기술연구소 논문지 Vol.21 No.2

The availability of microcontrollers and switching power devices such as power MOSFET, IGBT, TRIAC, ect., offer improvement opportunities in the field of ac drive system control. In this paper, a microprocessor-based controller for self-starting and power saving single phase induction motor driven system from a variable phase angle power supply is described. The controller is capable of operating in the maximum efficiency region as well as in the optimal input power region. The implementation of the software is based on an PIC16C71 8-bit programmable microcontroller that has the potential of computing the switching instants on line an in real-time. The variable phase angle switching strategy more employed for self-starting and phase angle control of the motor than the PWM switching strategy. The performance of the developed system is evaluated using computer simulation on a 210W capacitor starting motor. Finally the validity and performance capability of the controller are experimentally demonstrated on a 210W single phase induction motor.

입력전력제어에 의한 단상유도전동기의 효율개선에 관한 연구

백형래,박수강 조선대학교 에너지.자원신기술연구소 2000 에너지·자원신기술연구소 논문지 Vol.22 No.1

The paper presents a new drive for single-phase induction motor and a one-chip micom-based controller and control method for self-starting and Input power saving of single-phase induction motor driven from a phase angle control is described. The controller is capable of motor operating in the maximum efficiency region as well as in the optimal input power region. The implementation of the microprocessor is based on an 8-bit programmable micro-controller in low cost. The proposed method is based on the optimal efficiency control which is running by variable phase angle of main winding current of single-phase induction motors. The variable phase angle switching strategy more economized for self-starting and phase angle control of the motor than the PWM switching strategy in high cost. The implemented system consists of TRIAC for voltage control, starting capacitor, 8bit one-chip microcontroller for maximum efficiency control. Experiments are focused on a capacitor starting single-phase induction motor, the optimal Input energy saving by variable phase angle control are verified by experimental results. Also, auxiliary winding was controlled by electronic starting switch.

PFC를 적용한 AC/DC 승압형 컨버터 설계

백형래,박수강,최연옥,한엄용,이성길 조선대학교 에너지.자원신기술연구소 1999 에너지·자원신기술연구소 논문지 Vol.21 No.1

Single-Phase diode rectifiers are widely used in industry. These rectifier, however, generate many harmonic components in the AC Power line and have the poor input power factor, which may create a power quality problem for other electrical apparatus in the vicinity of the rectifier. Power factor improvement and harmonic reduction in the AC line current have become very significant problems in single-phase diode rectifiers. In this paper, the high power factor boost converter using soft switching is proposed to improve the demerit. The simulation results show the validity of the proposed system.

원칩마이크로컨트롤러를 이용한 단상유도전동기의 기동시스템 구현

백형래,박수강,최낙일 조선대학교 에너지.자원신기술연구소 1998 에너지·자원신기술연구소 논문지 Vol.20 No.2

A single phase induction motor(SPIM) with two windings, main and auxiliary is probably the most widely used motor in the world due to their ruggedness, low maintenance and simplicity of construction. There are several ways of starting single phase motors. The most popular arrangements is centrifugal switch. An auxiliary winding connected in series with a capacitor, is brought into the circuit during starting. The closing and opening of the switch must be speed dependant. The switch meets the speed requirements, but it also has many drawback: random switching, arcing, many models necessary for different speeds and shaft diameters, space required inside the motors and limited lifetime to name some of them. In this paper, authors present the experimental results of the SPIM under controlling of currents of main and auxiliary windings by using a one-chip micro starter. This new starting method is developed to replace the conventional starting device consisted with a mechanical switch and a capacitor. In mentioned method the soft-starting of SPIM is simply implemented and higher efficiency is obtained in comparison with conventional condenser type SPIM.

전류제어에 의한 단상유도전동기의 기동특성 개선

박수강,최낙일,백형래,임양수,이기용,신사현 조선대학교 에너지.자원신기술연구소 1998 에너지·자원신기술연구소 논문지 Vol.20 No.1

A single phase induction motor(SPIM) with two windings, main and auxiliary, is probably the most widely used motor in the world due to their ruggedness, low maintenance and simplicity of construction There are several ways of starting single phase motors The most popular arrangements is centrifugal switch An auxiliary winding connected in series with a capacitor, is brought into the circuit during starting The closing and opening of the switch must be speed dependant The switch meets the speed requirements, but it also has many drawback random switching, arcing, many models necessary for different speeds and shaft diameters, space required inside the motors and limited lifetime to name some of them. In this paper, the starting current of single phase induction motor was detected by a small detector and determined TRIAC gate signal. The strategy of current control is based on limited main and auxiliary current angle during starting period in the closed-loop control. The experimental result show the motor's starting characteristics of the proposal starting system and are compared with centrifugal switch starting motor.

AC/DC 승압형 컨버터의 입력특성 개선

백형래,박수강 조선대학교 에너지.자원신기술연구소 2000 에너지·자원신기술연구소 논문지 Vol.22 No.1

Single-Phase diode rectifiers are widely used in industry. These rectifier, however, generate many harmonic components in the AC Power line and have the poor input power factor, which may create a power quality problem for other electrical apparatus in the vicinity of the rectifier. Power factor improvement and harmonic reduction in the AC line current have become very significant problems in single-phase diode rectifiers. In this paper, the high power factor boost converter using soft switching is proposed t o improve the demerit. The simulation results show the validity of the proposed system.

디지털 제어에 의한 단상유도전동기의 범용 기동기 설계

최창주,서강성,박수강,조금배,백형래,임병옥 조선대학교 에너지.자원신기술연구소 2002 에너지·자원신기술연구소 논문지 Vol.24 No.2

Single phase induction motor(SPIM) is one of the most widely used type of low power AC motors in the world, especially for domestic or commercial applications where a three phase power supply is not available. Fractional horse power single phase induction motors have no starting torque their own. So there are several ways of starting single phase induction motors. The most common type is the starting capacitor installed in series with the auxiliary winding to increase the starting torque. Also, the auxiliary winding is disconnected once the speed of the motor reaches 70 to 80% of the rated speed. In the conventional systems, this function is conducted by a centrifugal switch. But the mechanical centrifugal switch has many problems such as switch malfunction. This paper presents the new methods of universal starting switch by digital controller to overcome these shortcomings of centrifugal switch.

유니버셜모터의 저차 고조파전류 저감을 위한 속도제어기에 관한 연구

임홍우,박수강,백형래 조선대학교 에너지.자원신기술연구소 2000 에너지·자원신기술연구소 논문지 Vol.22 No.1

Universal motors are commonly used for portable tools and other application. The universal motors can be implied AC or DC voltage source. Phase-angle control AC drive systems gain a high popularity due to their simple implementation despite the disadvantage of their poor input power factor especially for large values of phase delay angle. Futhermore it contains a large amount of subharmonic current. But pulse width modulation controlled DC drive systems reduce these problems. This paper compared the harmonic characteristics of phase angle control AC system that is controlled by TCA785 with zero voltage crossing similar to traditional system and DC chopper system that is used in PWM controller.

LC 공진형 PWM 인버터를 이용한 X선 발생장치의 특성에 관한 연구

이성길,박수강,임홍우,조금배,백형래,임양수 조선대학교 에너지.자원신기술연구소 2002 에너지·자원신기술연구소 논문지 Vol.24 No.1

The conventional types of X-ray generators were bulky in physical size and heavy in weight, and the control accuracies of the output voltages were not always satisfactory. The high frequency switching inverter and converter technology on power conversion and control systems have been greatly closed up introducing power semiconductor devices. In this paper, the newly developed converter to take the balance of the output voltage versus the ground are also presented in detail to decreasing the volume and the weight of high voltage transformer and to stabilize ripple. This converter consists of the two independent L-C series resonant circuits using the two capacitances and the two primary windings of high voltage transformer.

S-257 Prevalence of Polyvascular Disease in Korea: 10-year Korea Health Insurance Sample Cohort Database

( Lae Hyung Kang ),( Jeong Su Kim ),( Sang Hyun Lee ) 대한내과학회 2016 대한내과학회 추계학술발표논문집 Vol.2016 No.1

Background:?Nationwide epidemiologic data about of polyvascular disease in Korea are limited.?Methods:?Using the 10-year Korea Health Insurance Sample Cohort Database (KHISCDB), we performed a nationwide population-based epidemiologic study and investigated the prevalence of polyvascular disease including coronary artery disease (CAD), peripheral artery disease (PAD) and cerebrovascular disease (CVD).?Results:?A total of 1,025,340 people were screened from KHISCDB and 670,439 adult people were followed up from 2002 to 2010 (Fig A). A total of 94,984 (14.2%) patients were diagnosed as ASCVD: 56,185 patients as CAD, 49,608 patients as PAD and 28,594 patients as CVD. Of these patients, 63,014 patients (6.3%) have single arterial bed disease and 31,970 patients (33.7%) have polyvascular disease. 48.2% of the 56,185 patients with CAD, 52.2% of the 49,608 patients with PAD, and 64.4% of the 28,594 patients also have other ASCVD in other arterial territories (Fig B).?Conclusions:?The prevalence of polyvascular disease in Korea was higher than that of Western countries or worldwide data. This nationwide epidemiologic study offers an opportunity to provide to a better understanding of the prevalence of polyvascular disease in Korean populations and results of the study will be of practical relevance to physicians, health care organizations, and those who issue clinical guidelines for the reduction of ASCVD.