scholarly journals Fast calculation method of transient temperature rise of motor for electro-mechanical braking

2021 ◽  
Vol 104 (2) ◽  
pp. 003685042110245
Author(s):  
Yongming Tang ◽  
Xiangshen He ◽  
Jiawei Cao
Keyword(s):  
Working Conditions ◽  
Temperature Rise ◽  
Calculation Method ◽  
Response Speed ◽  
Development Trend ◽  
Fast Response ◽  
Transient Temperature ◽  
Compact Structure ◽  
Fast Calculation ◽  
Special Power

Electro-mechanical braking is a new braking mode of rail vehicles, which has the advantages of compact structure, fast response speed, and high precision. It is a new braking technology that conforms to the development trend of full electrification and full intelligence of rail transit brake devices. Due to the special power demand of the electro-mechanical braking device, the electro-mechanical braking motor has a short-time and intermittent working mechanism and is in the state of blocking during working, resulting in its high-temperature rise. Therefore, it is necessary to calculate the temperature rise of the motor quickly and accurately at the beginning of its design. To address this problem, based on the coupling calculation of the equivalent thermal circuit method and the equivalent magnetic circuit method, a fast temperature rise calculation method of the motor is proposed. Then, using the fast calculation method, the temperature rise of the electro-mechanical brake motor under different working periods and wind speed is calculated. By function fitting the calculated results, the motor temperature rise curve fitting function is obtained, which can accurately predict the temperature rise of the motor under different working conditions. It provides a theoretical basis for the use of electro-mechanical braking motor in different working conditions and also provides a reference for the design of the electro-mechanical braking motor.

Simulation Test System of Non-Contact D-dot Voltage Transformer

2016 ◽  
Vol 17 (2) ◽  
pp. 91-99 ◽  
Author(s):  
Jie Yang ◽  
Jingang Wang ◽  
Ruixi Luo ◽  
Can Gao ◽  
Li Songnong ◽  
...  
Keyword(s):  
Signal Processing ◽  
Displacement Vector ◽  
Electric Displacement ◽  
Response Speed ◽  
Development Trend ◽  
Fast Response ◽  
Test System ◽  
Voltage Measurement ◽  
Simulation Test ◽  
Voltage Transformer

Abstract The development trend of future voltage transformer in smart grid is non-contact measurement, miniaturization and intellectualization. This paper proposes one simulation test system of non-contact D-dot transformer for voltage measurement. This simulation test system consists of D-dot transformer, signal processing circuit and ground PC port. D-dot transformer realizes the indirect voltage measurement by measuring the change rate of electric displacement vector, a non-contact means (He et al. 2004, Principles and experiments of voltage transformer based on self-integrating D-dot probe. Proc CSEE 2014;15:2445–51). Specific to the characteristics of D-dot transformer signals, signal processing circuits with strong resistance to interference and distortion-free amplified sensor output signal are designed. WIFI wireless network is used to transmit the voltage detection to LabVIEW-based ground collection port and LabVIEW technology is adopted for signal reception, data processing and analysis and other functions. Finally, a test platform is established to simulate the performance of the whole test system of single-phase voltage transformer. Test results indicate that this voltage transformer has sound real-time performance, high accuracy and fast response speed and the simulation test system is stable and reliable and can be a new prototype of voltage transformers.

scholarly journals Review on the Development, Control Method and Application Prospect of Brake-by-Wire Actuator

Actuators ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 15 ◽  
Author(s):  
Xiaoxiang Gong ◽  
Weiguo Ge ◽  
Juan Yan ◽  
Yiwei Zhang ◽  
Xiangyu Gongye
Keyword(s):  
Control Method ◽  
Estimation Algorithm ◽  
Development Trend ◽  
Fast Response ◽  
Brake System ◽  
Research Trend ◽  
Force Distribution ◽  
Compact Structure ◽  
Distribution Method ◽  
Braking Force

This paper reviews and summarizes the development, key technologies, and application of brake-by-wire (BBW) actuators. BBW is the technology orientation of future vehicle brake system. The main feature of BBW is to replace some of the mechanical and hydraulic components of traditional brake system with electronic control components, and use cables and wires to transmit energy and signals. BBW actuators have outstanding advantages, such as fast response, accurate control, and compact structure. They are easy to integrate with active safety functions and they are easily matched with the regenerative braking systems of electric vehicle. First, this paper summarizes the classification, characteristics, performance, and architecture of BBW actuators. Subsequently, the braking process regulation of vehicle is considered to be the main target, which is summarized from two aspects of actuator regulation and braking force distribution. The state estimation algorithm and control algorithm applied to these actuators are summarized and analyzed, and the development trend, challenges, and schemes of the braking force distribution are proposed. The development and research trend of braking force match strategies between the regenerative brake system and BBW system are also analyzed and summarized. The further electrification and intelligence of vehicle demand BBW’s braking force control method and distribution method must have higher control accuracy, stronger robustness, and wider adaptability, and the effects on braking comfort and handling stability must be further discussed.

scholarly journals Tin Disulfide-Coated Microfiber for Humidity Sensing with Fast Response and High Sensitivity

Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 648
Author(s):  
Aijie Liang ◽  
Jingyuan Ming ◽  
Wenguo Zhu ◽  
Heyuan Guan ◽  
Xinyang Han ◽  
...  
Keyword(s):  
Humidity Sensor ◽  
Small Diameter ◽  
High Sensitivity ◽  
Large Change ◽  
Small Variation ◽  
Response Speed ◽  
Fast Response ◽  
Tin Disulfide ◽  
Recovery Times ◽  
Response And Recovery

Breath monitoring is significant in assessing human body conditions, such as cardiac and pulmonary symptoms. Optical fiber-based sensors have attracted much attention since they are immune to electromagnetic radiation, thus are safe for patients. Here, a microfiber (MF) humidity sensor is fabricated by coating tin disulfide (SnS2) nanosheets onto the surface of MF. The small diameter (~8 μm) and the long length (~5 mm) of the MF promise strong interaction between guiding light and SnS2. Thus, a small variation in the relative humidity (RH) will lead to a large change in optical transmitted power. A high RH sensitivity of 0.57 dB/%RH is therefore achieved. The response and recovery times are estimated to be 0.08 and 0.28 s, respectively. The high sensitivity and fast response speed enable our SnS2-MF sensor to monitor human breath in real time.

scholarly journals Self-Powered All-Inorganic Perovskite Photodetectors with Fast Response Speed

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Ting Zhang ◽  
Shibin Li
Keyword(s):  
High Performance ◽  
Solution Process ◽  
Response Speed ◽  
Fast Response ◽  
Single Step ◽  
Inorganic Perovskite ◽  
Perovskite Materials ◽  
Photoactive Materials ◽  
Self Powered ◽  
Solvent Processing

AbstractIn this manuscript, the inorganic perovskite CsPbI2Br and CsPbIBr2 are investigated as photoactive materials that offer higher stability than the organometal trihalide perovskite materials. The fabrication methods allow anti-solvent processing the CsPbIxBr3−x films, overcoming the poor film quality that always occur in a single-step solution process. The introduced diethyl ether in spin-coating process is demonstrated to be successful, and the effects of the anti-solvent on film quality are studied. The devices fabricated using the methods achieve high-performance, self-powered and the stabilized photodetectors show fast response speed. The results illustrate a great potential of all-inorganic CsPbIxBr3−x perovskites in visible photodetection and provide an effective way to achieve high performance devices with self-powered capability.

High performance self-powered CuZnS/GaN UV photodetectors with ultrahigh on/off ratio (3 × 108)

2021 ◽  
Vol 9 (14) ◽  
pp. 4799-4807
Author(s):  
Yong Zhang ◽  
Weidong Song
Keyword(s):  
Chemical Bath Deposition ◽  
High Performance ◽  
Response Speed ◽  
Fast Response ◽  
Uv Photodetector ◽  
Uv Photodetectors ◽  
Simple Chemical ◽  
Self Powered

P-CuZnS/n-GaN UV photodetector is prepared by a simple chemical bath deposition, showing excellent self-powered properties, including ultrahigh on/off ratio (3 × 108), fast response speed (0.14/40 ms) and large detectivity of 3 × 1013 Jones.

Design of Missile Autopilot with Aerodynamic Lift and Reaction Jets Based on Auto Disturbance Rejection Controller

2012 ◽  
Vol 472-475 ◽  
pp. 1036-1039
Author(s):  
Chong Yang ◽  
Ke Zhang ◽  
Mei Bai Lu
Keyword(s):  
Disturbance Rejection ◽  
Response Speed ◽  
Fast Response ◽  
Urgent Problem ◽  
Robust Performance ◽  
Active Disturbance Rejection ◽  
Disturbance Rejection Control ◽  
Lateral Pulse Jet ◽  
Aerodynamic Lift ◽  
Pulse Jet

First a new autopilot design model is presented for the interceptor missile with the blended aerodynamic lift and reaction jet. The reaction jet can improve the response speed, but the structure of control system becomes more complex. Therefore how to design control strategy properly is an urgent problem. Second, considering the discrete property of the lateral pulse jet thrusters and the continuous property of the aerodynamic fins, a kind of ADRC (active disturbance rejection control) autopilot system was designed for the aerodynamic lift/reaction jet missile. Finally, through a testing in the simulation of MATLAB, it is shown that, due to the sufficient utilization of the reaction jet, there is a significant improvement in the fast response and robust performance of the proposed controller. It is applicable to design the autopilot of aerodynamic lift and reaction jet blended missile.

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