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Duan Z.R.,Kunming University of Science and Technology | Huang G.Y.,Kunming University of Science and Technology | Huang G.Y.,Engineering Research Center for Mineral Pipeline Transportation | Shao Z.K.,Kunming University of Science and Technology | And 5 more authors.
Applied Mechanics and Materials | Year: 2014

In this paper, based on the principle of exponential approach law, an integral sliding mode controller (ISMC) for brushless doubly-fed machine (BDFM) adjustable speed system is presented. Because of using the integral sliding mode control, the proposed controller for BDFM employs the robustness and excellent dynamic performances of ISMC. Simulation results show that the proposed control strategy is of the feasibility, correctness and effectiveness. © (2014) Trans Tech Publications, Switzerland.


Zhang Z.,Kunming University of Science and Technology | Wu J.,Kunming University of Science and Technology | Wu J.,Engineering Research Center for Mineral Pipeline Transportation | Ma J.,Kunming University of Science and Technology | And 2 more authors.
Zhongnan Daxue Xuebao (Ziran Kexue Ban)/Journal of Central South University (Science and Technology) | Year: 2016

In order to extract the fault features of bearing slight fault, a new fault diagnosis method for rolling bearing based on chaos and fractal theory was put forward. Firstly, the largest lyapunov exponent of rolling bearing vibration signal was calculated to identify whether the bearing running gets in chaotic or not. Then, the correlation dimension and box dimension of the chaotic signal were calculated as the state character for fault diagnosis. When the correlation dimension can't obviously separate bearing faults, the box dimension is used to combine with it for fault diagnosis. Finally, the inner ring, outer ring and rolling element signal of bearing in slight fault, serious fault and the normal state signal in total 7 kinds of conditions were selected to do the experiments. The experimental results show that the method can accurately extract fault feature and complete slight fault diagnosis of rolling bearing. The proposed method provides a new effective approach to the fault diagnosis of rolling bearing. © 2016, Central South University of Technology. All right reserved.


Shao Z.K.,Kunming University of Science and Technology | Shao Z.K.,Engineering Research Center for Mineral Pipeline Transportation | Duan Z.R.,Kunming University of Science and Technology | Huang G.Y.,Kunming University of Science and Technology | Huang G.Y.,Engineering Research Center for Mineral Pipeline Transportation
Advanced Materials Research | Year: 2014

For maximum wind power tracking, the adaptive fuzzy sliding mode control is designed based on the method of rotation speed feedback of brushless doubly-fed machine. The adaptive fuzzy system approaches the uncertainties of generation system. A nonlinear integrator sliding mode control strategy is proposed to track the speed of wind. The stability of closed-system is proved using Lyapunov's method. Finally, the simulation studies are provided to confirm that the rotation speed of brushless doubly-fed machine can fast track the speed of wind. Then the maximum power-point tracking is gotten. © (2014) Trans Tech Publications, Switzerland.


Ma J.,Kunming University of Science and Technology | Wu J.,Kunming University of Science and Technology | Wu J.,Engineering Research Center for Mineral Pipeline Transportation | Yuan X.,Kunming University of Science and Technology
International Journal of Control and Automation | Year: 2013

The rolling bearing vibration is a complex, non-stationary and dynamic process. The vibration signal can not be described through a fixed time or frequency function. This increases the difficulty of fault diagnosis. Therefore, this paper proposed a rolling bearing fault diagnosis method based on local mean decomposition (LMD) and time-frequency analysis. Firstly, we need to draw time-domain waveform and power spectrum of vibration signal in this method. Secondly, we can gain the energy density distribution of signal using directly time-frequency analysis of signal, the time-frequency analysis of intrinsic mode function (IMF) and the time-frequency analysis of production function (PF). We gain the IMF by decomposing the original signal by the ensemble empirical mode decomposition (EEMD).and after the original signal is decomposed by the local mean decomposition,we gain the PF .Finally, according to the energy density distribution of signal, diagnose the fault of the rolling bearing. The simulation results show that we can gain the clearer the energy density distribution using the time-frequency of PF of signal to diagnose fault and improve the reliability of the fault diagnosis.


Liu Y.,Kunming University of Science and Technology | Fan Y.,Kunming University of Science and Technology | Fan Y.,Engineering Research Center for Mineral Pipeline Transportation
Proceedings of the 2015 27th Chinese Control and Decision Conference, CCDC 2015 | Year: 2015

For some current problems in mineral production, such as measuring difficulty and low accuracy rate, how to do on the mineral yield accurate and convenient measurement is very important. This paper presents a remote mineral output monitoring system based on GPRS. The overall structure of the system includes monitoring terminal, GPRS wireless transmission network and monitoring service center three parts. After the mineral production was weighted by weighing equipment, the obtained data information will transmit to the microprocessor through RS232. After STM32 on the data processor, storage, and then via RS485 bus to send data to GPRS communication module, and then the data is sent over the Internet to the server. Conversely The client can access the server to control the monitoring of mineral output data, to achieve the real-time and accurate monitoring of mineral production. © 2015 IEEE.


Qi P.,Kunming University of Science and Technology | Qi P.,Engineering Research Center for Mineral Pipeline Transportation | Fan Y.,Kunming University of Science and Technology | Fan Y.,Engineering Research Center for Mineral Pipeline Transportation | And 2 more authors.
Proceedings of the 2015 27th Chinese Control and Decision Conference, CCDC 2015 | Year: 2015

In order to extract the weak fault information from rolling bearing vibration signals, a method of feature extraction of bearing vibration signal based on singular value decomposition (SVD) and generalized S-transform module matrix was proposed. Firstly, mutant information is separated from the noise background and smooth signal by using SVD, according to the distribution state of singular value, selecting the transition stage of the singular value to extract mutant signal; then using the mean value of sum of squares of generalized S-transform module matrix amplitude to locate mutant information and the fault feature of bearing vibration signals are extracted for fault diagnosis. This method is used for representing characteristics of the bearing outer circle and inner circle partial fault, and through the fundamental frequency information can accurately detect and identify the type of fault. The result shows that this method proposed here is feasible and effective. © 2015 IEEE.


Zhang Z.,Kunming University of Science and Technology | Wu J.,Kunming University of Science and Technology | Wu J.,Engineering Research Center for Mineral Pipeline Transportation | Ma J.,Kunming University of Science and Technology | And 3 more authors.
Proceedings of the 2015 27th Chinese Control and Decision Conference, CCDC 2015 | Year: 2015

The vibration signal of rolling bearing is complex and nonstationary. In this paper, in order to overcome the difficulty of rolling bearing fault diagnosis, lifting wavelet and morphological fractal dimension are combined, puts forward a method based on lifting wavelet and morphological fractal dimension for rolling bearing fault diagnosis. The step of the diagnosis goes as follows: firstly, decompose the vibration signal of rolling bearing into three layers by lifting wavelet transform and restructure it, then analyze energy spectrum of the reconstructed signal to get the energy distribution of signal in time-frequency domain. Secondly, calculate the morphological fractal dimension of energy in time-frequency domain to judge the status of bearing. Finally, the morphological fractal dimension of bearing vibration signal in time domain and time-frequency domain would be compared. The result shows that the status of bearing can be distinguished more accuracy through the propoesd method. © 2015 IEEE.


Wang M.,Kunming University of Science and Technology | Wu J.,Kunming University of Science and Technology | Wu J.,Engineering Research Center for Mineral Pipeline Transportation | Wang X.,Kunming University of Science and Technology | Wang X.,Engineering Research Center for Mineral Pipeline Transportation
Proceedings of the 28th Chinese Control and Decision Conference, CCDC 2016 | Year: 2016

This paper introduced the relationship between the slurry pipeline resistance loss and the pipeline flow and determined the formula of the critical non-deposit velocity based on the assumption that momentum obtained from water is all transferred to maintain the suspended movement or passage of the slurry solids. Shilin Zhang et al. experimental data is used to examine the model. The results have shown that the maximum error of the measured values and calculated values, by using the formula, is 13.5%, indicating that it has higher calculation precision and it can satisfy engineering practical application requirements of the critical nondeposit velocity comparing with other critical nondeposit velocity formula. © 2016 IEEE.


Chen X.,Kunming University of Science and Technology | Chen X.,Engineering Research Center for Mineral Pipeline Transportation | Wu J.,Kunming University of Science and Technology | Wu J.,Engineering Research Center for Mineral Pipeline Transportation | And 2 more authors.
Proceedings of the 28th Chinese Control and Decision Conference, CCDC 2016 | Year: 2016

Aiming at the complexity of solid-liquid two phase flow theory analysis and experiment operation as well as the theory calculation model which fails to be widely applied due to its strong experience dependency, this paper hereby brings forward a numerical simulation of Euler-Euler two fluid model and carries out analyses on the pressure drop and flow-pattern change law of solid-liquid two phase flow under solid volume fraction and velocity change on the basis of analysis on experiment data and calculation model. According to the experiment result, CFD numerical simulation result is perfectly consistent with the computed result and measured data with regard to analysis on the pressure drop change law, but CFD numerical simulation result shows a comparatively smaller error than the measured data, it can well reflect the slurry flow law inside the pipeline and provide certain references for researches on solid-liquid two phase flow of horizontal pipeline. © 2016 IEEE.


Yu K.,Kunming University of Science and Technology | Huang G.,Kunming University of Science and Technology | Huang G.,Engineering Research Center for Mineral Pipeline Transportation | Gao Y.,Engineering Research Center for Mineral Pipeline Transportation
Proceedings of the 28th Chinese Control and Decision Conference, CCDC 2016 | Year: 2016

For the purpose that cycle-slips could be detected and repaired to increase navigation precision, a method based on ensemble empirical mode decomposition (EEMD) was proposed to detect small single-frequency cycle-slips. First of all, a second-order different equation was solved according to observations of pseudo-range and carrier-phase. Next, the differential sequence obtained was used for detecting cycle-slips and decomposed via EEMD into several intrinsic mode functions. Furthermore, all IMF variables were transformed into local instantaneous amplitudes through Hilbert transform, while areas where cycle-slips appeared could be detected based on the point at which the amplitude was the highest. At last, the method put forward in this paper was empirically verified to be effective for detecting single-frequency carrier phases to observe cycle-slips and accurate for detecting small cycle-slips within one to five cycles. © 2016 IEEE.

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