• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2000년도 추계학술대회 학술발표 논문집
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• pp.497-505
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• 2000

퍼지 논리 제어기(FLC)는 복잡한 프로세스와 비선형 프로세스와 비선형 프로세스에 사용되기 위해 연구되어져왔다. PI형 퍼지 제어기는 가장 보편적이고 실용적이다. 그러나 종래의 PI형 퍼지 제어기들은 큰 불감대를 가진 시스템이나 비선형 시스템에 대해 큰 오버슛과 과도한 발진으로 인해 불안정하다. 본 논문에서는 PI형 퍼지 제어기에서 제어 입력의 축적에 의해 야기된 오버슛을 제거하기 위한 관점에서, 두 개의 퍼지 제어기를 사용하여 좋은 성능을 이루기 위해, 직접적인 성능치로부터가 아니라, 현재의 프로세스 경향에만 의존하여, 조정하는 제어동작들을 발생하는 자기 동조 메카니즘을 사용하였다. 시뮬레이션 결과, 비선형 프로세스뿐만 아니라 선형의 다양한 형태를 갖는 프로세스에서 제안된 PI형 퍼지 제어기가 종래의 제어기의 성능을 능가한다는 것을 보여준다.

• 한국기계가공학회지
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• 제2권4호
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• pp.73-81
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• 2003

DC series wound motor is commonly used for the industrial vehicles. Although it has good operating torque, heavy variations of parameters and nonlinear properties on friction and loads make it difficult to satisfy desired performance using conventional controllers. To solve this problem, fuzzy controller is proposed in this paper. The fuzzy controller has been designed based on the fuzziness of variables, it retains robustness even with nonlinearity.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.1659-1663
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• 1991

A new control design methodology is presented here which is based on a nonlinear time-series reference model. It is indicated by highly nonlinear simulations that such designs successfully stabilize troublesome aircraft maneuvers undergoing large changes in angle of attack as well as large electric power transients due to line faults. In both applications, the nonlinear controller was significantly better than the corresponding linear adaptive controller. For the electric power network, a flexible a.c. transmission system (FACTS) with series capacitor power feedback control is studied. A bilinear auto-regressive moving average (BARMA) reference model is identified from system data and the feedback control manipulated according to a desired reference state. The control is optimized according to a predictive one-step quadratic performance index (J). A similar algorithm is derived for control of rapid changes in aircraft angle of attack over a normally unstable flight regime. In the latter case, however, a generalization of a bilinear time-series model reference includes quadratic and cubic terms in angle of attack. These applications are typical of the numerous plants for which nonlinear adaptive control has the potential to provide significant performance improvements. For aircraft control, significant maneuverability gains can provide safer transportation under large windshear disturbances as well as tactical advantages. For FACTS, there is the potential for significant increase in admissible electric power transmission over available transmission lines along with energy conservation. Electric power systems are inherently nonlinear for significant transient variations from synchronism such as may result for large fault disturbances. In such cases, traditional linear controllers may not stabilize the swing (in rotor angle) without inefficient energy wasting strategies to shed loads, etc. Fortunately, the advent of power electronics (e.g., high-speed thyristors) admits the possibility of adaptive control by means of FACTS. Line admittance manipulation seems to be an effective means to achieve stabilization and high efficiency for such FACTS. This results in parametric (or multiplicative) control of a highly nonlinear plant.