This paper presents a novel adaptive commutation error compensation strategy for the sensorless brushless DC (BLDC) motor based on flux linkage function. It addresses two key challenge problems control of BLDC motor. The one is presenting detection method rotor position signal to filter out interference and noise by high frequency. other proposing improve system efficiency. In traditional strategy, deep low-pass usually used obtain from high-frequency interference. However, delayed angle...

This paper focuses on the sensorless high-precision position correction strategy for a 100 kW@20 000 r/min brushless dc (BLdc) motor with low stator inductance (0.051 mH). Two key points related to were studied. The one is rotor detection high-frequency interference. other commutation compensation high-speed BLdc in whole speed range. In order filter out interference, main factors, which that can influence and accuracy analyzed. compensate error range, relationship between angle phase...

This paper presents a novel sensorless startup strategy for 315-kW high-speed magnetic suspension brushless dc (BLDC) motor with small inductance and nonideal back electromotive force (EMF). Two key strategies on the of BLDC are presented: First, current inductance; second, self-adaption control to compensate commutation error EMF in stage. A hybrid pulsewidth modulation based load torque is proposed limit current. An optimal curve system parameters presented, solve synchronous switching...

Abstract The hard suckers commonly used in surgical operations often cause adsorption extrusion damage to the biological tissue. To tackle this problem, from perspective of bionics, through in-depth observation and research on special sucker process mechanism hypostomus plecostomus (HP), paper proposes a bionic soft (BSHPS) with variable stiffness gradient structure good performance moist irregular tissues. BSHPS comprises lip disc, pre-valvular cavity, post-valvular cavity. Through volume...

摘要: 军事侦察打击、远程运输和医疗救援对飞机的性能要求不断提高,传统机翼在提升飞行效率和任务适应性等方面存在瓶颈,制约着飞机性能提升。智能柔性变形机翼将柔性材料、变形结构和分布控制与传感等技术结合起来,实时感知载荷和姿态并自适应变形,在不同环境和任务下都获得优异性能,对克服传统机翼不足、提升飞机性能具有重要作用。目前,国内外学者已开展相关研究,虽然取得一定进展,但是存在若干问题限制了技术的应用发展,亟待探讨解决方法。介绍智能柔性变形机翼的研究现状,分析关键问题,指出在柔性蒙皮、变形机构、分布控制、智能感知和系统集成与协同等方面的研究重点和方法,并对未来发展提出建议。

A method for evaluating the profile error of complex surfaces, particularly worm, with Minimum Zone Method (MZM) by way particle swarm optimization (PSO) is presented. According to minimum zone condition, mathematical model surface together optimal objective function derived. The principle and implementation PSO are explained algorithm introduced search solution. Experiments show that capable nonlinear problems such as can obtain solutions. solutions agree well result given Least Square...

To advance the development of a compact and highly integrated fiber Bragg grating (FBG) interrogation system, to best our knowledge, this paper is first present design fabrication monolithic integration chip based on silicon-on-insulator (SOI), which specifically intended for application in sensing systems. By considering impact coupling structure dimensions efficiency as well effect photodetector (PD) parameters optical absorption device, we refine arrayed waveguide (AWG) PD. The test...

In the above paper <xref ref-type="bibr" rid="ref1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">[1]</xref> , Toker <italic xmlns:xlink="http://www.w3.org/1999/xlink">et al.</i> proposed a general solution of branch-line coupler which is perfect design. Since this was published, it has been widely cited by and referenced in other papers patents. However, when we referred to it, found wrong equation. The expression...

An unequal power divider which features quasi-arbitrary output phase difference is proposed in this paper.The circuit consists of four microstrip lines and a resister.By the even-and odd-mode analysis technique, closed-form design equations structure are derived.The characteristic impedances, electrical length bandwidth variations with division ratio analyzed.For proving its validity, prototype designed implemented at 1 GHz.The results simulation measurement show that can effectively produce...

The acousto optic modulator drive is mainly made with 2 amplitude shift keying (2ASK)circuit, pre-amplifier circuit and power operational amplifier circuit, the simulation of realized. Firstly, works as follows.The modulation function realized by analoged switch on-off chip (CD4066) are controlled pulse signal generated electronic conversion circuit. voltage amplification modulated achieved two reverse proportional operation implements AD8001 chip. Then amplified transfered into a two–stage...

Measurement points are obtained using a CMM. Lyite rule is used to optimize the data. The algebra relationship between independent parameters and Cartesian coordinate system built parametric equations of Archimedes helicoid surface error about constructed. acquired use least square method. Experimental results show that proposed method can be make values close theoretical values, so, it do other kinds fitting surface.

In this paper we propose a uniform mathematic model of helicoidal surfaces. We describe the spacing surface and properties studie description real surfaces on basis, derive deviations from its model. provide an algorithm for compensation stylus radius. This research is useful to unify measurement all kinds parts simplify measuring procedures.

Limited by AWG output characteristics, currently reported AWG-based interrogation systems cannot simultaneously achieve high resolution and extensive dynamic range. This manuscript has fabricated a monolithically integrated novel SOI-based as crucial part of the fiber Bragg grating system (FBGI). Input waveguide is modified inserting 1*2 MMI coupler. The combination input coupler can add another peak in spectral that at least two channels have significant signal any wavelength be measured....