• Journal of Electrical Engineering and Technology
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• 제12권2호
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• pp.769-777
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• 2017

The research of air gap flux density has a significant effect on predicting and optimizing the structure parameters of electrical machines. In the paper, the air gap coefficient, leakage flux factor and saturation coefficient are first analytically expressed in terms of motor properties and structure parameters. Subsequently, the analytical model of average air gap flux density for surface-mounted permanent magnet synchronous machines is proposed with considering slotting effect and saturation. In order to verify the accuracy of the proposed analytical model, the experiment and finite element analysis (FEA) are used. It shows that the analytical results keep consistency well with the experimental result and FEA results, and the errors between FEA results and analytical results are less than 5% for SPM with high power. Finally, the analytical model is applied to optimizing the motor structure parameters. The optimal results indicate that the analytical calculation model provides a great potential to the machine design and optimization.

• Journal of Power Electronics
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• 제14권5호
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• pp.980-988
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• 2014

This paper proposes an online gain tuning algorithm for a robust sliding mode speed controller of surface-mounted permanent magnet synchronous motor (SPMSM) drives. The proposed controller is constructed by a fuzzy neural network control (FNNC) term and a sliding mode control (SMC) term. Based on a fuzzy neural network, the first term is designed to approximate the nonlinear factors while the second term is used to stabilize the system dynamics by employing an online tuning rule. Therefore, unlike conventional speed controllers, the proposed control scheme does not require any knowledge of the system parameters. As a result, it is very robust to system parameter variations. The stability evaluation of the proposed control system is fully described based on the Lyapunov theory and related lemmas. For comparison purposes, a conventional sliding mode control (SMC) scheme is also tested under the same conditions as the proposed control method. It can be seen from the experimental results that the proposed SMC scheme exhibits better control performance (i.e., faster and more robust dynamic behavior, and a smaller steady-state error) than the conventional SMC method.

• 한국산학기술학회논문지
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• 제20권4호
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• pp.517-522
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• 2019

본 논문은 전동기 상수 추정 방법을 제안한다. 제안하는 기법은 전동기 전압방정식을 차동식 형태로 전개한 수식에 기반한다. 차동식 형태를 이용함으로써 전동기 상수 추정시 사용되는 전압 정보에 존재하는 크기 오차인 데드타임의 영향을 배제한다. 전동기의 상수값은 전동기 제어 성능 향상을 위해서 필요할 때가 있다. 예를 들면 DTC(Direct Torque Control) 제어 기법에는 토오크 및 자속 크기의 연산시 전동기의 상수를 알아야한다. 다른 예로서 예측제어의 경우 지령치 전압 생성을 위해서는 정확한 전동기의 상수 값의 정보가 필요하다. 전동기의 상수는 구동 환경에 따라 변동하는 값이므로 부정확한 전동기 상수 사용시 제어 성능의 저하를 가져온다. 따라서, 정확한 전동기 상수의 추정이 필요하다. 제안하는 기법에서 전압차동식에 기초하여 추정되는 전동기 상수는 RLS(Recursive Least Square) 기법에 의해 구해진다. 본 연구에서는 단순 수식에 의한 형태로 전동기의 상수를 추정하지 않고, RLS 알고리즘을 적용하여 노이즈에 강인하게 전동기 상수를 추정한다. 표면 부착형 영구자석 전동기의 제어시스템에 적용하여 제안하는 기법의 타당성을 보인다.

• Journal of Magnetics
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• 제22권1호
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• pp.78-84
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• 2017

This paper investigates the influence of mechanical energy storage on the interior permanent magnet synchronous machine (IPMSM) when it is operated in the generating mode. An IPMSM with six-poles and nine-slots employing concentrated coil winding type is considered as the analysis model, and a surface-mounted permanent magnet synchronous motor directly connected to a heavy wheel is applied as the mechanical energy storage system by using the moment of inertia. Based on the constructed experimental set-up with manufactured machines and power converters, the generated electrical energy is converted into the mechanical energy, and the electromagnetic filed characteristics of IPMSM are subsequently investigated by applying the measured phase current of IPMSM based on finite element method. Compared to the characteristics in a no-load condition, it is confirmed that the magnetic behavior, radial force, and power loss characteristics are highly influenced by the harmonics of the phase current due to the mechanical energy storage system.

• 전력전자학회논문지
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• 제9권2호
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• pp.112-118
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• 2004

본 논문은 선박 추진 장치를 위한 저속 영역에서 최대 토크를 내는 대용량 BLDCM(Brushless DC motor)의 설계에 관한 연구이다. 기존의 추진 장치용 모터는 직류기 및 권선형 유도 전동기 등을 사용함으로 인하여 유지 보수가 필요하였다. 본 논문에서는 유지 보수가 필요 없고 저속에서 큰 토크를 발생 할 수 있는 BLDCM 설계를 하였다. 설계시 출력 리플 및 진동, 소음을 유발하는 코깅 토크 저감을 고려하기 위해 설계변수로 공극길이와 자극 각 등을 취하여 이의 변화에 대한 최저 코깅 토크를 가지는 최적형상을 구하고, 전동기 특성을 FEM과 Maxwell stress tensor법을 이용하여 해석하였다. 최저의 코깅 토크를 가지며 저속영역에서 최대 토크를 발생 할 수 있는 선박 추진 장치용 SPM type의 BLDCM을 설계하였다.

• 제어로봇시스템학회논문지
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• 제9권5호
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• pp.347-353
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• 2003

A nonlinear speed controller for a surface mounted permanent magnet synchronous motor (PMSM) based on a newly developed adaptive backstepping approach is presented To compensate parameter uncertainties and load torque disturbance, a nonlinear adaptive backstepping control law and adaptive law are derived systematically through virtual control input and suitable Lyapunov function. Also, speed observer without using costly speed sensor is presented. Simulation results show that the proposed controller can observe the speed and track the reference speed signal generated by a reference model.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1991년도 하계학술대회 논문집
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• pp.543-547
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• 1991

This paper illustrates maximum torque per ampare radio operation and efficiency operation, which are prevalently applied to the control of permanent magnet synchronous motor(PMSM). Maximum torque per ampare ratio operation minimizes the copper loss of PMSM and maximum efficiency operation minimizes the total loss of PMSM. To verify the difference of these method, simulation and experiment results applied to IPMSM(Interior type PMSM) and SPMSM(Surface mounted PMSM) are presented.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.290-293
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• 1994

This paper proposes a servo control system of SPMSM (Surface-mounted Permanent Magnet Synchronous Motor) which essentially uses vector control method. The control system is composed of the PI controller for speed control and the current controller using space voltage vector PWM technique. The high-speed processing of algorithm for vector control and inverter switching for PWM is carried out by TMS320C31 DSP and IGBT module, respectively. The proposed scheme for 2.2kW SPMSM is verified through digital simulations and experiments, which show higher performance than that of traditional hysteresis current control technique.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.752-754
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• 2004

Super high speed motors and generators are increasing in various applications such as air compressor, gas turbine and fuel cell systems because of small size and light weight at the same power level. This paper presents an experiment and simulation for a permanent magnet synchronous motor(PMSM) in super high speed applications.

• Journal of Power Electronics
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• 제19권2호
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• pp.497-508
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• 2019

The predictive speed control (PSC) strategy can realize the simultaneous control of speed and current by using one cost function. As a model-based control method, the performance of the PSC is vulnerable to model mismatches such as load torque disturbances and parameter uncertainties. To solve this problem, this paper presents a robust predictive speed control (RPSC) strategy for surface-mounted permanent magnet synchronous motor (SPMSM) drives. The proposed RPSC uses extended state observers (ESOs) to estimate the lumped disturbances caused by load torque changes and parameter mismatches. The observer-based prediction model is then compensated by using the estimated disturbances. The introduction of ESOs can achieve robustness against predictive model uncertainties. In addition, a modified cost function is designed to further suppress load torque disturbances. The performance of the proposed RPSC scheme has been corroborated by experimental results under the condition of load torque changes and parameter mismatches.