• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.1047-1048
• /
• 2011

본 논문에서는 IPMSM(Interior Permanent Magnet Synchronous Motor)의 단점인 치, 슬롯 구조에 의한 코깅 토크를 최소화시켜 정토크 특성을 향상시키기 위해 배리어(Barrier)와 노치(Notch)를 설치하였다. 실험계획법 및 유한요소해석을 통하여 최적 설계를 수행하고 그에 따른 제반 특성과 진동 및 소음의 원인이 되는 가진력 특성을 고찰 하였다.

• Journal of Institute of Control, Robotics and Systems
• /
• v.7 no.9
• /
• pp.766-773
• /
• 2001

Omni-directional mobile robots have been popularly employed in several application areas. However, the kinematics for these systems have not been clearly identified, specially for redundantly actuated case which is common in omni-directional mobile robot such as the Nomadic model. For such mobile robot systems, exploitation of redundant actuation as well as singularity analysis has not been extensively addressed. In light of this fact, this paper introduces two different kinematic approaches for omni-directional mobile robots. Then, a singular-free load distribution scheme for redundantly actuated three-wheeled omni-directional mobile robot is proposed. Through simulation, several advantages of redundantly actuated mobile robot in aspect of singularity avoidance, minimization of torque norm, and exploiting several subtasks are presented.

• Journal of Electrical Engineering and Technology
• /
• v.4 no.2
• /
• pp.201-210
• /
• 2009

A loss minimizing controller is developed for a fuel cell electric vehicle (FCEV) permanent magnet synchronous motor (PMSM). The PMSM losses are modeled by some experimental equations. Applying Lagrangian to the loss function, a necessary condition for the optimality appears to be a fourth order polynomial, and the loss minimizing solutions are obtained by a simple numerical approach. On the other hand, the loss minimizing solutions are found by scanning the motor loss in the entire operating region. The two results agree well. The loss minimizing current sets for given torque and speed are made into a table, which is utilized as a look-up in the current control loop.

• Proceedings of the KIEE Conference
• /
• 2004.10a
• /
• pp.126-128
• /
• 2004

This paper deals with an automatic optimum design based on capacity for a synchronous reluctance motor (SynRM). The focus of this paper is the design relative to the output power on the basis of rotor shape of a SynRM in each capacity. And optimization algorithm is used by means of sequential unconstrained minimization technique(SUMT). The coupled Finite Elements Analysis (FEA) & Preisach model have been used to evaluate nonlinear solutions. The proposed procedure allows to define the rotor geometric dimensions according to capacity starting from an existing motor or a preliminary design.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.646_647
• /
• 2009

소형 다상 외전형 BLDC 전동기의 코깅토크를 최소화하기 위해 코깅토크의 발생원인 중 하나인 영구자석의 형상에 샘플링 포인트 기법인 LHS를 이용한 최적화 알고리즘을 적용하여 코깅토크를 최소화하는 최적 설계를 수행 하였다. 총 3번의 반복계산을 하여 코깅토크가 최소화 되는 최적점을 계산한 결과,최대 코깅토크가 0.20 [N.m]에서 0.15 [N.m]로, 초기 형상의 약 75%로 감소되었다

• Proceedings of the KIPE Conference
• /
• 2012.11a
• /
• pp.223-224
• /
• 2012

본 논문은 퍼지 기반의 토크 분배 함수를 이용한 스위치드 릴럭턴스 모터의 토크 맥동 저감 기법을 제안한다. 일반적으로 스위치드 릴럭턴스 모터의 토크 맥동 저감 기법은 선행된 실험결과와 모터 파라미터의 변화에 대한 관측을 통해 오프라인으로 토크 분배 함수를 최적화한다. 이때, 모터의 높은 인덕턴스는 전류가 토크 분배 함수를 잘 추종하지 못하게 하여 의도치 않은 토크 맥동을 유발한다. 게다가 오프라인으로 토크 분배 함수를 계산하기 때문에 모델의 오차 및 변화에 따라 보상 성능이 저하 될 수 있다. 제안하는 제어기법은 퍼지 제어기를 이용하여 순시적으로 토크 분배 함수의 형상을 정정함으로써 토크 맥동을 저감한다. 시뮬레이션 결과를 통해 제안하는 제어기법의 우수성을 보인다.

• Journal of the Korean Society for Precision Engineering
• /
• v.14 no.6
• /
• pp.90-98
• /
• 1997

A time-optimal control law for quick, strongly nonlinear systems has been developed and demonstrated. This procedure involves the utilzation of neural networks as state feedback controllers that learn the time-optimal control actions by means of an iterative minimization of both the final time and the final state error for the systems with constrained inputs and/or states. A neural identifier or a genetic algorithm identifier could be utilized for modeling the partially known systems and the unknown systems. The nature of neural networks as a parallel processor would circumvent the problem of "curwe of dimensionality". The control law has been demonstrated for both a torque input motor and a velocity input motor identified by a genetic algorithm called GENOCOPed GENOCOP.

• Proceedings of the KIEE Conference
• /
• 2008.10c
• /
• pp.32-34
• /
• 2008

Latin Hypercube sampling strategy(LHS)는 출력변수에 의한 목적함수들의 기댓값의 추정을 위한 입력변수를 생성하는데 사용할 수 있는 샘플링 포인트 추출 방법으로, 샘플링 포인트의 "quality"를 향상시켜준다. multi-objective Pare optimization 에 근거한 LHS와 ($1+\lambda$) 진화기법으로 이루어진 최적화 algorithm을 제안 하였고, 이를 이용하여 6MW BLDC 전동기의 코깅토크를 최소화 하였다, 총 2단계의 최적 설계를 통해 초기형상의 코킹토크에 비해 19%로 감소하였다.

• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.649-651
• /
• 2015

This paper describes a robust adaptive sliding mode control (RASMC) for torque ripple minimization of switched reluctance motor (SRM) using it in automotive application. The objective is to control effort smoothness while the system is under perturbations by unstructured uncertainties, unknown parameters and external disturbances. The control algorithm employs an adaptive approach to remove the need for prior knowledge within the bound of perturbations. This is suitable for tackling the chattering problem in the sliding motion of sliding mode control method. The algorithm then incorporates modifications in order to build a chattering-free modified robust adaptive sliding mode control using Lyapunov stability theory.

• Proceedings of the KIEE Conference
• /
• 2002.11d
• /
• pp.138-140
• /
• 2002

This paper deals with an automatic design procedure for the minimization of iron core loss in a synchronous reluctance motor (SynRM). The focus of this paper is the design relative to hysteresis loss on the basis of rotor shape of a SynRM in the same torque density. The coupled Finite Elements Analysis (FEA) & Preisach model have been used to evaluate the iron core loss with the rotor shape. The proposed procedure allows to define the rotor geometric dimensions starting from an existing motor or a preliminary design. The iron loss has been reduced with a rotor design variation.