Programmable PWM modulator optimized for high speed for OPWM test platform

Author(s):  
Jan Kubak ◽  
Jakub Stastny ◽  
Petr Kujan
Keyword(s):  
2011 ◽  
Vol 341-342 ◽  
pp. 868-872
Author(s):  
Hui Xin Zhang ◽  
Yan Lu Zheng ◽  
Yan Ran Chen ◽  
Hai Guang Yang

To match, test, and determine the working conditions and correctness of each function of the aircraft measurement system. This article proposes a design of equivalent test platform which can produce digital and analog signals for the self-testing of measurement system. By using the ethernet protocol chip W5300 to achieve the high-speed communication between host computer and equivalent device. Communication uses UDP unicast data transfer mode with advantages of high-speed and long-distance transmission, and the Phenomenon of data packet loss is not easy in transmission.


1997 ◽  
Vol 200 (24) ◽  
pp. 3091-3099 ◽  
Author(s):  
S A Shaffer ◽  
D P Costa ◽  
T M Williams ◽  
S H Ridgway

The white whale Delphinapterus leucas is an exceptional diver, yet we know little about the physiology that enables this species to make prolonged dives. We studied trained white whales with the specific goal of assessing their diving and swimming performance. Two adult whales performed dives to a test platform suspended at depths of 5-300 m. Behavior was monitored for 457 dives with durations of 2.2-13.3 min. Descent rates were generally less than 2 m s-1 and ascent rates averaged 2.2-3 m s-1. Post-dive plasma lactate concentration increased to as much as 3.4 mmol l-1 (4-5 times the resting level) after dives of 11 min. Mixed venous PO2 measured during voluntary breath-holds decreased from 79 to 20 mmHg within 10 min; however, maximum breath-hold duration was 17 min. Swimming performance was examined by training the whales to follow a boat at speeds of 1.4-4.2 m s-1. Respiratory rates ranged from 1.6 breaths min-1 at rest to 5.5 breaths min-1 during exercise and decreased with increasing swim speed. Post-exercise plasma lactate level increased to 1.8 mmol l-1 (2-3 times the resting level) following 10 min exercise sessions at swimming speeds of 2.5-2.8 m s-1. The results of this study are consistent with the calculated aerobic dive limit (O2 store/metabolic rate) of 9-10 min. In addition, white whales are not well adapted for high-speed swimming compared with other small cetaceans.


2011 ◽  
Vol 383-390 ◽  
pp. 4486-4491
Author(s):  
Zhong Quan Luan ◽  
Hu Yan Ji ◽  
Qing Dong Yang

Linear Motors have been used more and more widely in high precision and high-speed linear motion for CNC machine tools, but uniform testing standards and methods for linear motor performance have not been established in China. Based on the virtual instrument software platform by means of computer technology, research and development of the test platform for synthetic performance parameters of linear motors can realize the rapid and accurate measurement, automatic storage and processing of linear-motor output, currents, positions, temperatures and other performance parameters. , Meanwhile, the platform can also provide the technical direction for design or improvement of linear motors, and technically support the formulation of related standards. Experiments showed that the test platform for synthetic performance parameters of linear motors can achieve high precision and automatic measurement to meet the testing requirements for synthetic performance of linear motors.


2020 ◽  
Vol 28 (3) ◽  
pp. 213-231
Author(s):  
Wanming Zhai ◽  
Kaiyun Wang ◽  
Zhaowei Chen ◽  
Shengyang Zhu ◽  
Chengbiao Cai ◽  
...  

Abstract Motivated by the huge practical engineering demand for the fundamental understanding of mechanical characteristics of high-speed railway infrastructure, a full-scale multi-functional test platform for high-speed railway track–subgrade system is developed in this paper, and its main functions for investigating the mechanical performance of track–subgrade systems are elaborated with three typical experimental examples. Comprising the full-scale subgrade structure and all the five types of track structures adopted in Chinese high-speed railways, namely the CRTS I, the CRTS II and the CRTS III ballastless tracks, the double-block ballastless track and the ballasted track, the test platform is established strictly according to the construction standard of Chinese high-speed railways. Three kinds of effective loading methods are employed, including the real bogie loading, multi-point loading and the impact loading. Various types of sensors are adopted in different components of the five types of track–subgrade systems to measure the displacement, acceleration, pressure, structural strain and deformation, etc. Utilizing this test platform, both dynamic characteristics and long-term performance evolution of high-speed railway track–subgrade systems can be investigated, being able to satisfy the actual demand for large-scale operation of Chinese high-speed railways. As examples, three typical experimental studies are presented to elucidate the comprehensive functionalities of the full-scale multi-functional test platform for exploring the dynamic performance and its long-term evolution of ballastless track systems and for studying the long-term accumulative settlement of the ballasted track–subgrade system in high-speed railways. Some interesting phenomena and meaningful results are captured by the developed test platform, which provide a useful guidance for the scientific operation and maintenance of high-speed railway infrastructure.


2021 ◽  
Vol 12 (1) ◽  
pp. 85-96
Author(s):  
Yun Zhang ◽  
Meng Li ◽  
Hongzhi Yao ◽  
Yanjie Gou ◽  
Xiaoyu Wang

Abstract. The unbalance-induced vibration of a high-speed rotor directly affects the manufacturing accuracy. To effectively suppress this undesired vibration and avoid the complicated process of using trial weights during the balancing adjustment, a modal-based balancing method for a high-speed rotor without trial weights is proposed. First, the matrix sweep operation is employed to acquire the unbalance equivalent plane (EP). Next, the equivalent concentration methods, using the vector feedback principle (VFP) and modal equivalent principle (MEP), respectively, are studied and compared, while the equivalent transfer of the continuous unbalance vector to the EP is realized. Then, through modal analysis and the MEP, a balancing method, without trial weights required, is proposed for the high-speed rotor, which only needs to collect vibration data below critical speed. Finally, the rotor model and the presented method are validated on a rotor test platform, where the simulation and experiment results show that the unbalance-induced vibration has been effectively suppressed, ensuring smooth and safe operation of the rotor at high speed.


2013 ◽  
Vol 278-280 ◽  
pp. 155-158
Author(s):  
Yue Feng Yuan ◽  
Guo Liang Tao ◽  
Hao Liu ◽  
Wei Ban

Aim to fulfill the design requirements of a pneumatic proportional directional valve, a novel bidirectional proportional electromagnet with integrated lineal Hall position sensor was proposed. Magnetic circuit model and finite element model were established separately. Both static force vs. armature stroke characteristic and Hall sensor output vs. armature position were tested on a newly designed test platform. The experimental result shows a good linear magnetic spring characteristic of the proportional electromagnet, which further ensures a unique spool auto reset capability for directional valves. The mass of the armature is considerably reduced, thus it will benefit the overall performance of high speed pneumatic proportional directional valves.


2020 ◽  
pp. 039139882094493
Author(s):  
Shu Li ◽  
Juan Yan ◽  
Tingting Wu ◽  
Po-Lin Hsu

Objective: For ventricular assist devices utilizing levitation bearing technology, collision and wear of the rotor would occur if the bearing cannot resist disturbances from patient activities and vibration/shock impacts. The reliability of ventricular assist devices can be seriously affected, potentially impairing blood compatibility (e.g. thrombus generation) and threatening patient safety. In this article, we proposed a vibrational disturbance test protocol for ventricular assist devices. Methods: Two kinds of vibrational disturbances—translational and rotational—were defined and the disturbance levels determined as 6G and 10 rad/s per possible patient activity impact. A test platform was built according to the disturbance level requirements. Results: The test platform successfully generated the required disturbance. The vibration test evaluation criteria for ventricular assist device assistance (characterized by the pressure head, flow rate, and driving current waveform) were well verified. Conclusion: Compared with translational vibration, rotational vibration had a greater impact on the rotor. Accurate control of high-speed rotor is difficult because of the gyroscopic effect. As conventional random vibration tests cannot cover all risk situations, it is recommended that translational and rotational disturbance tests are carried out for levitation ventricular assist devices. We recommend that researchers and manufacturers pay attention to the vibrational impact of rotor-levitated ventricular assist devices.


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