Termal Design and Temperature Control Method of Motor Drives for Stratospheric Airships

Author(s):  
Li Chujia ◽  
Zhang Qinling ◽  
Qian Hao
2018 ◽  
Vol 10 (12) ◽  
pp. 168781401881527 ◽  
Author(s):  
Xudong Liu ◽  
Ke Li

A novel speed control method based on sliding mode control and disturbance observer is studied for permanent magnet synchronous motor drives. Different from the conventional speed and current cascade control structure in the field-oriented vector control, the new controller adopts the single-loop control structure, in which the speed and quadrate axes current controllers are combined together. First, a multiple-surface sliding mode controller is designed for the speed control system of permanent magnet synchronous motor. Although the sliding mode controller has the strong robustness for the matched disturbance in the system, it still cannot deal with mismatched disturbance effectively, such as external load disturbance and some parameter variations. Thus, the disturbance observer is introduced to estimate the disturbance in the motor, which is designed by combining the proposed sliding mode controller. Finally, the effectiveness is tested under various conditions by both simulation and experiment. The results show that the designed controller has the fast transient response and robustness under different operating conditions.


2012 ◽  
Vol 594-597 ◽  
pp. 738-741 ◽  
Author(s):  
Yin Duan ◽  
Xing Hong Liu ◽  
Xiao Lin Chang

Main factors of the temperature control and crack prevention in arch dams are summarized. The Space-time Dynamic Control method in pipe cooling process and the Temperature Real-time Control and Decision Database System are introduced to help for temperature real-time control and rapid analysis. Successful application of these new techniques in the construction of Dagangshan arch dam indicates that the proposed method are of significant effectiveness on the temperature control and crack prevention, and have good application prospect in practical project.


2011 ◽  
Vol 2-3 ◽  
pp. 966-971
Author(s):  
Wen Yi Lin ◽  
Minoru Sasaki ◽  
Hirohisa Tamagawa

Unlike well-investigated polymer-based soft actuators such as gel, Ionic Polymer-Metal Composite, conducting polymer, a CFRP-based polymeric laminate possesses quite distinguished properties. It was previously reported that a CFRP-PVC laminate exhibited two-way deflection in accordance with environmental temperature, but it was asymmetric deflection due to the asymmetric laminate structure. In this study, we successfully fabricated a new CFRP-based polymeric laminate which can exhibit symmetric deflection. Despite such a successful outcome, there was large room to improve the degree of its deflection. Improvement of temperature control method for the newly fabricated CFRP-based polymeric laminate resulted in enhancement of the degree of its deflection.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jingjing Pan ◽  
Yanni Tai ◽  
Haibin Qu ◽  
Xingchu Gong

Abstract Ethanol precipitation is an important separation and purification process in the traditional Chinese medicines (TCMs) industry. In the present study, a membrane dispersion micromixer was applied to achieve good mixing for the ethanol precipitation process of Astragali radix concentrate. New experimental apparatus was set up to rapidly lower the temperature of ethanol solution before mixing with the concentrate. Ethanol precipitation process was optimized according to Quality by design concept. To identify critical material attributes (CMAs), ten batches of Astragali radix were used to prepare concentrates. Calycosin-7-O-β-D-glucoside content, the sucrose content, and the electrical conductivity were found to be CMAs after the correlation analysis and stepwise regression modelling. Definitive screening design was used to investigate the relationships among critical process parameters, CMAs, and process critical quality attributes (CQAs). Quadratic models were developed and design space was calculated according to the probability of attaining process CQA standards. A material quality control strategy was proposed. High quality and low quality Astragali radix concentrates can be discriminated by the inequalities. Low quality Astragali radix concentrates should not be released for ethanol precipitation process directly. Verification experiment results indicated accurate models and reliable design space. The temperature control method and control strategy are promising for ethanol precipitation process of other TCMs or foods.


2013 ◽  
Vol 416-417 ◽  
pp. 890-894
Author(s):  
Xiao Hui Guo

Tobacco Warehousing is chiefly applied to preserve the tobacco that is separated into leaf and stem so that the tobacco moisture is controlled at the range of technology demand.The present control method of tobacco save is that the references of every PID control link are set up and adjusted by human experience. So, the control effect varies with the individual and the output tobacco moisture can't maintain stable.The fuzzy-PID temperature system is based on CC2430 single chip. It includes the power source, the manipulative algorithm, the temperature examination , the correspondence of up PC and the output-control of the switch value and so on. Computer takes the parameter deviation and the deviation change as input, and the PID controllers parameters of ΔKp, Δki, ΔKd as output. The sub program realized the corresponding events by completing zone bit and zone bit judgment. The main program realized temperature control function by calling the wireless micro-controller sends a signal to the charged unit


Sign in / Sign up

Export Citation Format

Share Document