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21.
永磁同步电机无传感器控制技术不但能够降低系统成本,而且能够增加系统的可靠性。为实现永磁同步电机无位置传感器的运行,本文提出了一种基于自适应滑模观测器的非线性速度/角度估算方法,基于永磁同步电机的数学模型,根据实测电流与估算电流之间的误差构成滑模面,将反电动势估算值反馈引入电机电流观测中。为简化调速系统的硬件结构,我公司设计了一个截止频率可随转速变化的低通滤波器。 相似文献
22.
《Mechatronics》2021
Robots are an indispensable part of modern production lines. Usually working in designated areas, they are separated from human workers in order to avoid collisions. A safe collaborative work environment is enabled by so-called soft robots, which constitute a human-friendly alternative to classical rigid industrial robots. However, modeling soft robots proves difficult and results in a lack of accuracy for control tasks. In this contribution, a disturbance observer-based control is proposed in order to improve tracking behavior. In doing so, unknown model errors are considered as disturbances and estimated by an observer. This estimate is used to actively reject the perturbation. Different disturbance observers are designed and implemented for a soft quasi-continuum manipulator, amongst them two nonlinear disturbance observers and two extended state observers. The distinction in the versions of the same observation concept lies in the disturbance dynamics assumption, which is either considered static or as a damped double integrator. All implemented concepts combined with a PD control show superior performance compared to an existing benchmark concept based on PID-like control. Thanks to the modularity of this approach, disturbance observers can be further investigated in combination with other control strategies. 相似文献
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M. Meinhardt V. Leonavicius J. Flannery S. C.
Mathúna 《Microelectronics Reliability》1999,39(10):1461
This paper deals with thermal and reliability aspects of converters for grid connected photovoltaic applications (rate power approximately 100 W) which can be integrated into solar modules. The use of these Module Integrated Converters (MIC) promises a reduction of costs due to mass production. It improves behaviour of the whole photovoltaic system, as there is no voltage mismatch caused by shading effects. The electronic components of the MIC are exposed to extreme environmental conditions. Lifetime limiting factors are described. Methods to increase the lifetime of the most crucial components in the MIC, electrolytic capacitors, are described. The presented 1st generation Low Profile MIC with “optimised design” is capable of running in very high ambient temperatures. This design maximises availability of the photovoltaic system, which consequently leads to a cost reduction of the electrical energy delivered to the grid. Different realisations of how to integrate the designed Low Profile MIC into the solar module are discussed. A detailed thermal simulation is used to optimise the MIC design according to temperature and reliability issues. The models used for thermal simulation are described. 相似文献
27.
为了提高红外导引头的跟踪精度,降低导气管对导引头控制系统的影响,提出一种新型可变增益扰动观测器。首先,利用搭建的导引头实验系统研究了导气管干扰的扰动特性。然后,在分析导气管扰动的系统特性基础之上,结合经典扰动观测器理论,设计了新型可变增益扰动观测器,并分析了其鲁棒稳定性。最后,针对某实际红外导引头系统,设计了可变增益扰动观测器,并进行了导气管扰动抑制实验。结果表明:经典扰动观测器无法对导气管的扰动进行有效的抑制,而采用可变增益扰动观测器后,系统速度阶跃响应稳定精度提高71.1%;位置阶跃响应稳定精度提高42.8%。研究表明可变增益扰动观测器可以有效地抑制红外导引头中的导气管扰动。 相似文献
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W.-R. Liou T.-H. Chen M.-L. Yeh J.-J. Ho G. E. Jan 《International Journal of Electronics》2013,100(6):623-632
A fully integrated dual-band LC voltage control oscillator, designed in a 0.18-µm CMOS technology for 5.8-GHz/2.0-GHz wireless communication applications, is described. The frequency band switching is accomplished with switched-inductor technique. The dual-band oscillator can be operated in 5.38–6.23?GHz and 1.78–2.07?GHz with 15% frequency tuning range. Two different inductors are used for the frequency band switching. Frequency tuning is implemented by varying the capacitance of a MOS varactor. The measured phase noise is ?109?dBc/Hz @ 1?MHz and ?112?dBc/Hz @ 1?MHz for frequency at 5.8?GHz and 2?GHz, respectively. This oscillator is fabricated in UMC's 0.18-µm one-poly-six-metal 1.8?V process. The power dissipation of this dual-band VCO is 11.7 and 9.3?mW for oscillation frequency of 2?GHz and 5.8?GHz, respectively. 相似文献
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Sanjeev Kumar Pandey S. L. Patil Praveen V. Pol S. B. Phadke 《International Journal of Electronics》2020,107(10):1682-1703
ABSTRACT In this paper, two control schemes for boost converters affected by uncertainties in input voltage and load are proposed. The boost converter dynamics is redefined in terms of new state variables to facilitate the use of a disturbance observer that can estimate matched and unmatched disturbances. A sliding surface, which is new in the context of boost converters, is proposed to enable tracking and regulation of output voltage without requiring measurement of input voltage and load current. The stability of the overall system including the disturbance observer, the sliding variable and the output is proved. The performance of the schemes is assessed for regulation of output voltage and tracking of reference voltage by simulation as well as experimentation in which various types of uncertainties and various types of reference voltages are considered. 相似文献