scholarly journals Troubleshooting of Matrix Frequency Converter Conducted and Radiated Emissions

2010 ◽  
Vol 27 (1) ◽  
pp. 146-151
Author(s):  
Gundars Asmanis ◽  
Leonids Ribickis ◽  
Vladimirs Novikovs
Keyword(s):  
Output Voltage ◽  
Electromagnetic Compatibility ◽  
Low Cost ◽  
Frequency Converter ◽  
Matrix Converter ◽  
Point Of View ◽  
Standard Equipment ◽  
Sinusoidal Input ◽  
Radiated Emissions ◽  
Electronics And Electrical

Troubleshooting of Matrix Frequency Converter Conducted and Radiated EmissionsMatrix converter inherently exhibits sinusoidal input current waveforms and has less stressful output voltage waveforms, but it is causing problems with conducted and radiated emissions. This paper deals with matrix converter emitted disturbances from point of view of electromagnetic compatibility (EMC) standard EN61800-3 and allocates the sources of undesirable emissions using standard equipment used for EMC assessment according to variety international EMC standards and discusses methodology of troubleshooting flow, using low cost equipment available in almost every laboratory of Industrial Electronics and Electrical Engineering.

A Single-Stage DC Uninterruptible Power Supply

2015 ◽  
Vol 764-765 ◽  
pp. 466-470
Author(s):  
Maoh Chin Jiang ◽  
Bing Jyun Shih
Keyword(s):  
Power Factor ◽  
Power Supply ◽  
Output Voltage ◽  
High Efficiency ◽  
Low Cost ◽  
Single Stage ◽  
Normal Operation ◽  
Uninterruptible Power Supply ◽  
Sinusoidal Input ◽  
Uninterruptible Power

A single-stage DC uninterruptible power supply (UPS) is proposed in this paper. Basically, the proposed converter is an integration result of a power factor correction circuit with a dc-to-dc converter to achieve simple hardware circuit, high efficiency, and low cost for extra UPS function. Under normal operation, a novel two-switch SEPIC converter operates as an ac to dc converter with sinusoidal input current, unity power factor, and low ripple dc output voltage, and as a battery charger if a battery is added. Since both the input boost supply and the output supply can be controlled independently, a fast transient response can be maintained at both the input for active current wave shaping and at the output for good output regulation. When the ac source is in an outage condition, the proposed converter functions as a dc-to-dc buck-boost converter; therefore, the desired dc output voltage can be provided. Finally, some experimental results are presented for verification.

FREQUENCY CONVERTER WITH THE REDUCED THD OF THE OUTPUT VOLTAGE

2016 ◽  
Vol 2016 (5) ◽  
pp. 14-16 ◽  
Author(s):  
G.V. Pavlov ◽  
◽  
I.L. Vinnichenko ◽  
A.V. Obrubov ◽  
◽  
...  
Keyword(s):  
Output Voltage ◽  
Frequency Converter

scholarly journals A Feasibility Study of the Use of Smartwatches in Wearable Fall Detection Systems

Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 2254
Author(s):  
Francisco Javier González-Cañete ◽  
Eduardo Casilari
Keyword(s):  
Low Cost ◽  
Fall Detection ◽  
The Elderly ◽  
Point Of View ◽  
False Alarms ◽  
Battery Life ◽  
Area Network ◽  
Battery Lifetime ◽  
Detection Systems ◽  
Operational Aspects

Over the last few years, the use of smartwatches in automatic Fall Detection Systems (FDSs) has aroused great interest in the research of new wearable telemonitoring systems for the elderly. In contrast with other approaches to the problem of fall detection, smartwatch-based FDSs can benefit from the widespread acceptance, ergonomics, low cost, networking interfaces, and sensors that these devices provide. However, the scientific literature has shown that, due to the freedom of movement of the arms, the wrist is usually not the most appropriate position to unambiguously characterize the dynamics of the human body during falls, as many conventional activities of daily living that involve a vigorous motion of the hands may be easily misinterpreted as falls. As also stated by the literature, sensor-fusion and multi-point measurements are required to define a robust and reliable method for a wearable FDS. Thus, to avoid false alarms, it may be necessary to combine the analysis of the signals captured by the smartwatch with those collected by some other low-power sensor placed at a point closer to the body’s center of gravity (e.g., on the waist). Under this architecture of Body Area Network (BAN), these external sensing nodes must be wirelessly connected to the smartwatch to transmit their measurements. Nonetheless, the deployment of this networking solution, in which the smartwatch is in charge of processing the sensed data and generating the alarm in case of detecting a fall, may severely impact on the performance of the wearable. Unlike many other works (which often neglect the operational aspects of real fall detectors), this paper analyzes the actual feasibility of putting into effect a BAN intended for fall detection on present commercial smartwatches. In particular, the study is focused on evaluating the reduction of the battery life may cause in the watch that works as the core of the BAN. To this end, we thoroughly assess the energy drain in a prototype of an FDS consisting of a smartwatch and several external Bluetooth-enabled sensing units. In order to identify those scenarios in which the use of the smartwatch could be viable from a practical point of view, the testbed is studied with diverse commercial devices and under different configurations of those elements that may significantly hamper the battery lifetime.

Natural Locomotion Based on Foot-Mounted Inertial Sensors in a Wireless Virtual Reality System

2015 ◽  
Vol 24 (4) ◽  
pp. 298-321 ◽  
Author(s):  
Ernesto de la Rubia ◽  
Antonio Diaz-Estrella
Keyword(s):  
Virtual Reality ◽  
Gait Cycle ◽  
Inertial Sensors ◽  
Low Cost ◽  
Point Of View ◽  
Handheld Devices ◽  
Preliminary Evaluation ◽  
Virtual Reality System ◽  
Object Searching

Virtual reality has become a promising field in recent decades, and its potential now seems clearer than ever. With the development of handheld devices and wireless technologies, interest in virtual reality is also increasing. Therefore, there is an accompanying interest in inertial sensors, which can provide such advantages as small size and low cost. Such sensors can also operate wirelessly and be used in an increasing number of interactive applications. An example related to virtual reality is the ability to move naturally through virtual environments. This is the objective of the real-walking navigation technique, for which a number of advantages have previously been reported in terms of presence, object searching, and collision, among other concerns. In this article, we address the use of foot-mounted inertial sensors to achieve real-walking navigation in a wireless virtual reality system. First, an overall description of the problem is presented. Then, specific difficulties are identified, and a corresponding technique is proposed to overcome each: tracking of foot movements; determination of the user’s position; percentage estimation of the gait cycle, including oscillating movements of the head; stabilization of the velocity of the point of view; and synchronization of head and body yaw angles. Finally, a preliminary evaluation of the system is conducted in which data and comments from participants were collected.

Flexural Joints in Mechanisms

2000 ◽  
Author(s):  
M. P. Koster
Keyword(s):  
Consumer Goods ◽  
Design Methodology ◽  
Low Cost ◽  
Point Of View ◽  
Industrial Technology ◽  
Scientific Instruments ◽  
Manufacturing Equipment ◽  
Flexural Fatigue ◽  
Elastic Deflection ◽  
Flexural Joints

Abstract The application of flexural joints in mechanisms has a number of advantages. Extreme repeatability of position is obtained because of the absence of backlash and friction. From a tribological point of view, no lubrication is needed and no wear exists. In many cases their application gives rise to a low cost assembly. Flexural elements have their particular drawbacks as well. Deflections are limited; only oscillating motions can be performed and work has to be done as a consequence of the elastic deflection. Flexural fatigue sets another limit to their application. The paper gives an overview of a design methodology that has been developed at the Philips Center for Industrial Technology by the author and his colleagues over the last several decades. Some aspects of this methodology are well known; other aspects are unique. The methodology is described in detail in a book by the author about design principles (Koster 1998). The methodology has been used to design hundreds of practical mechanisms incorporated in scientific instruments, manufacturing equipment and consumer goods. Many examples are given in (Koster 1998). Several interesting examples are given in this paper.

Evaluating and Exploring Successful Disruptive Innovation in the Aviation Industry From the Perspective of Consumers

2021 ◽  
Vol 13 (4) ◽  
pp. 105-119
Author(s):  
Gang-Hoon Seo
Keyword(s):  
Word Of Mouth ◽  
Low Cost ◽  
Disruptive Innovation ◽  
Point Of View ◽  
Aviation Industry ◽  
Basic Service ◽  
Low Cost Carriers ◽  
Content Analyses ◽  
Southwest Airlines

Since Southwest Airlines' disruptive innovation was introduced, low-cost carriers (LCCs) have had a prominent impact on the aviation industry. Therefore, considerable attention has been paid to the LCC model. However, it is still not clear whether it is a successful disruptive innovation, or what factors and differentiation points for successful LCC service exist from the passengers' perspective. As this study's methodology, quantitative and qualitative content analyses are conducted using the word-of-mouth data of 1,854 passengers of 20 airlines. This study found that the LCC model is perceived as a successful disruptive innovation from the passengers' point of view. For successful LCC service, LC airlines should offer higher quality services than passengers' expectations using basic service elements. Also, good staff characteristics, leaving a professional impression, and providing good optional services could play a role as differentiation tools.

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