scholarly journals FEATURES OF SECTIONING THE TURNS OF THE TRANSFORMING ELEMENT OF THE TRANSFORMER-KEY ACTUATING STRUCTURE IN THE BOOST CHANNEL OF THE DC POWER SYSTEM

2020 ◽  
Vol 2020 (6) ◽  
pp. 25-31
Author(s):  
K.O. Lypkivskyi ◽  
◽  
A.G. Mozharovskyi ◽  
Keyword(s):  
High Efficiency ◽  
A Priori ◽  
Current Source ◽  
Voltage Regulation ◽  
Specific Class ◽  
Voltage Supply ◽  
Emergency Situations ◽  
Time Control ◽  
Finite Set ◽  
In Series

One of the effective ways to ensure the normalized operation of the electricity consumer with an unstable primary power source is the organization of the corresponding voltage supply channel. In a system with a direct current source, the voltage supply is implemented by introducing a rectifier semiconductor bridge in series with the load, into the diagonal of which AC energy is supplied, the voltage level of which is purposefully changed by a corresponding converter with a transformer- and-switches executive structure (TSES). To achieve high efficiency of the use of key elements of TSVS, it is proposed to assign the functions of rectification and voltage regulation to a specific class of TSES – a multilevel rectifier consisting of a transformer and a finite set of parallel connected pairs of serially connected thyristors, the common points of which are connected to the corresponding taps of the sectioned secondary turns of the transformer. By discrete-time control of thyristors, it is necessary to regulate voltage levels, it is attached. The linearity of the scale of these levels is ensured by the proposed transformer sectioning law. This power supply system is characterized by small energy losses in semiconductor elements (only two thyristors work at a time), and the a priori impossibility of emergency situations during transitions from one level to another. References 14, figures 3, tables 3.

Design and Simulation of LED Drive Power Supply Based on ARM

2012 ◽  
Vol 588-589 ◽  
pp. 936-939
Author(s):  
Hong Li Cheng ◽  
Xiao Dan Ren ◽  
Shuai Sun
Keyword(s):  
Power Supply ◽  
High Efficiency ◽  
Current Source ◽  
Constant Current ◽  
Voltage Source ◽  
Drive Power ◽  
Small Current ◽  
Constant Current Source ◽  
Pid Algorithm ◽  
In Series

This paper introduces a kind of numerical controlled LED drive power supply based on ARM7. User can set the number and brightness of the LEDs to be lit by the remote control. Switching voltage source and the linear constant current source are connected in series, this circuit structure can ensure high efficiency and small current ripple. ARM7 completes the data collection, fuzzy PID algorithm processing, and real-time output adjustment. This paper explains the working principle of the system in detail and then simulates it in the simulink. The results show that it can satisfy the users' diverse requirements well and give full play to the convenience and controllability of the digital controller.

Recognizing Job Apathy Patterns of Iraqi Higher Education Employees Using Data Mining Techniques

2019 ◽  
Vol 54 (4) ◽  
Author(s):  
Mustafa S. Abd ◽  
Suhad Faisal Behadili
Keyword(s):  
Higher Education ◽  
Data Mining ◽  
Psychiatric Patients ◽  
Human Life ◽  
A Priori ◽  
Psychological Research ◽  
Attribute Selection ◽  
Specific Class ◽  
Data Mining Techniques ◽  
Using Data

Psychological research centers help indirectly contact professionals from the fields of human life, job environment, family life, and psychological infrastructure for psychiatric patients. This research aims to detect job apathy patterns from the behavior of employee groups in the University of Baghdad and the Iraqi Ministry of Higher Education and Scientific Research. This investigation presents an approach using data mining techniques to acquire new knowledge and differs from statistical studies in terms of supporting the researchers’ evolving needs. These techniques manipulate redundant or irrelevant attributes to discover interesting patterns. The principal issue identifies several important and affective questions taken from a questionnaire, and the psychiatric researchers recommend these questions. Useless questions are pruned using the attribute selection method. Moreover, pieces of information gained through these questions are measured according to a specific class and ranked accordingly. Association and a priori algorithms are used to detect the most influential and interrelated questions in the questionnaire. Consequently, the decisive parameters that may lead to job apathy are determined.

scholarly journals A High Efficiency Low Noise RF-to-DC Converter Employing Gm-Boosting Envelope Detector and Offset Canceled Latch Comparator

Electronics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1078
Author(s):  
Thi Thuy Pham ◽  
Dongmin Kim ◽  
Seo-Hyeong Jeong ◽  
Junghyup Lee ◽  
Donggu Im
Keyword(s):  
Power Consumption ◽  
High Efficiency ◽  
Supply Voltage ◽  
Current Source ◽  
Low Noise ◽  
The Body ◽  
Common Source ◽  
Conversion Gain ◽  
Input Transistor ◽  
Envelope Detector

This work presents a high efficiency RF-to-DC conversion circuit composed of an LC-CL balun-based Gm-boosting envelope detector, a low noise baseband amplifier, and an offset canceled latch comparator. It was designed to have high sensitivity with low power consumption for wake-up receiver (WuRx) applications. The proposed envelope detector is based on a fully integrated inductively degenerated common-source amplifier with a series gate inductor. The LC-CL balun circuit is merged with the core of the envelope detector by sharing the on-chip gate and source inductors. The proposed technique doubles the transconductance of the input transistor of the envelope detector without any extra power consumption because the gate and source voltage on the input transistor operates in a differential mode. This results in a higher RF-to-DC conversion gain. In order to improve the sensitivity of the wake-up radio, the DC offset of the latch comparator circuit is canceled by controlling the body bias voltage of a pair of differential input transistors through a binary-weighted current source cell. In addition, the hysteresis characteristic is implemented in order to avoid unstable operation by the large noise at the compared signal. The hysteresis window is programmable by changing the channel width of the latch transistor. The low noise baseband amplifier amplifies the output signal of the envelope detector and transfers it into the comparator circuit with low noise. For the 2.4 GHz WuRx, the proposed envelope detector with no external matching components shows the simulated conversion gain of about 16.79 V/V when the input power is around the sensitivity of −60 dBm, and this is 1.7 times higher than that of the conventional envelope detector with the same current and load. The proposed RF-to-DC conversion circuit (WuRx) achieves a sensitivity of about −65.4 dBm based on 45% to 55% duty, dissipating a power of 22 μW from a 1.2 V supply voltage.

A High-efficiency Method for Linear Precision AC Voltage Regulation and Filtering

2020 ◽  
Author(s):  
Baichao Chen ◽  
Wei Gao ◽  
Yaojun Chen ◽  
Yuxiong Zhou ◽  
Gang Xue ◽  
...  
Keyword(s):  
High Efficiency ◽  
Voltage Regulation

scholarly journals Contribution of Voltage Support Function to Virtual Inertia Control Performance of Inverter-Based Resource in Frequency Stability

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4220
Author(s):  
Dai Orihara ◽  
Hiroshi Kikusato ◽  
Jun Hashimoto ◽  
Kenji Otani ◽  
Takahiro Takamatsu ◽  
...  
Keyword(s):  
Reactive Power ◽  
Control Function ◽  
Current Source ◽  
Voltage Control ◽  
Frequency Stability ◽  
Voltage Regulation ◽  
System Stability ◽  
Voltage Source ◽  
Apparent Difference ◽  
Virtual Inertia

Inertia reduction due to inverter-based resource (IBR) penetration deteriorates power system stability, which can be addressed using virtual inertia (VI) control. There are two types of implementation methods for VI control: grid-following (GFL) and grid-forming (GFM). There is an apparent difference among them for the voltage regulation capability, because the GFM controls IBR to act as a voltage source and GFL controls it to act as a current source. The difference affects the performance of the VI control function, because stable voltage conditions help the inertial response to contribute to system stability. However, GFL can provide the voltage control function with reactive power controllability, and it can be activated simultaneously with the VI control function. This study analyzes the performance of GFL-type VI control with a voltage control function for frequency stability improvement. The results show that the voltage control function decreases the voltage variation caused by the fault, improving the responsivity of the VI function. In addition, it is found that the voltage control is effective in suppressing the power swing among synchronous generators. The clarification of the contribution of the voltage control function to the performance of the VI control is novelty of this paper.

Multivariate Constrained GNSS Real-time Full Attitude Determination Based on Attitude Domain Search

2018 ◽  
Vol 72 (2) ◽  
pp. 483-502
Author(s):  
Hongtao Wu ◽  
Xiubin Zhao ◽  
Chunlei Pang ◽  
Liang Zhang ◽  
Bo Feng
Keyword(s):  
Objective Function ◽  
Success Rate ◽  
High Efficiency ◽  
Attitude Determination ◽  
A Priori ◽  
Three Dimensional ◽  
Satellite System ◽  
New Method ◽  
Lambda Method ◽  
Attitude Angle

A priori attitude information can improve the success rate and reliability of Global Navigation Satellite System (GNSS) multi-antennae attitude determination. However, a priori attitude information is nonlinear, and integrating a priori information into the objective function rigorously will increase the complexity of an ambiguity domain search, such as the Multivariate Constrained-Least-squares Ambiguity Decorrelation Adjustment (MC-LAMBDA) method. In this paper, a new method based on attitude domain search is presented to make use of the a priori attitude angle information with high efficiency. First, the a priori information of pitch and roll is integrated into the search process to derive the analytic search step for attitude angle, and the integer candidates are determined by traversal search in the three-dimensional attitude domain. Then, the objective function is parameterised with Euler angles, and a non-iterative approximate method is utilised to simplify the iterative computation in calculating objective function values. Experimental results reveal that compared to the MC-LAMBDA method, our new method has the same success rate and reliability, but higher efficiency in making use of a priori attitude information.

scholarly journals Amplitude electro-optical modulation of radiation by sequences of Fabry-Perot resonators

2020 ◽  
Vol 56 (2) ◽  
pp. 217-223
Author(s):  
V. B. Zalesski ◽  
A. I. Konoiko ◽  
V. M. Kravchenko ◽  
H. S. Kuzmitskaya
Keyword(s):  
Lithium Niobate ◽  
High Efficiency ◽  
Optical Modulation ◽  
Operating Point ◽  
Optical Modulator ◽  
Control Voltage ◽  
Clock Frequency ◽  
Fabry Perot ◽  
In Series ◽  
Light Signals

In this paper, we considered the method of amplitude electro-optical modulation of radiation using sequences of Fabry-Perot resonators based on the transverse electro-optical effect on the example of lithium niobate LiNbO3. With this method, it is possible to significantly reduce the voltage of the control electromagnetic field of the electro-optical amplitude modulator operating in the transmission mode of the light beam while maintaining its high efficiency. The reduction of the control voltage is achieved by increasing the number of Fabry-Perot resonators installed in series and the phase shift relative to the extremum of the transmittance function. This method allows to diminish the duration of the received light signals which leads to an increase in the clock frequency while maintaining a high efficiency of the radiation modulation. Diminishing the duration of light signals is achieved by using separate modulation channels of two sequences of electro-optical Fabry-Perot resonators, the first of which works on the transmission and the second one on the reflection. Increasing the clock frequency at the output of the modulator is achieved by summing the signals coming from several modulation channels. It is shown that the value of the control voltage for an amplitude electro-optical modulator based on a sequence of Fabry-Perot resonators made of lithium niobate LiNbO3, with an operating wavelength of 1.307 microns, can be 4 V in the case when its initial operating point corresponds to the maximum transmittance. The control voltage is 2 V if the initial operating point is shifted in phase relative to the extremum of the transmittance function.

scholarly journals High-Flexibility MPPT Techniques with Communication Scan Network for PV Micro-Grid System

Processes ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 117
Author(s):  
Yu-Kai Chen ◽  
Hong-Wen Hsu ◽  
Chau-Chung Song ◽  
Yu-Syun Chen
Keyword(s):  
Output Voltage ◽  
High Efficiency ◽  
Maximum Power ◽  
Global Maximum ◽  
Switching Frequency ◽  
Grid System ◽  
Pv System ◽  
In Series ◽  
Micro Grid ◽  
High Flexibility

This paper proposes the design and implementation of inductor-inductor-capacitor (LLC) converters with modules connected in series with the power scan method and communication scan network (CSN) to achieve MPPT and regulate the output voltage for the PV micro-grid system. The Dc/Dc converters includes six isolated LLC modules in series to supply ±380 V output voltage and track the maximum power point of the PV system. The series LLC converters are adopted to achieve high efficiency and high flexibility for the PV micro-grid system. The proposed global maximum power scan technique is implemented to achieve global maximum power tracking by adjusting the switching frequency of the LLC converter. To improve the system flexibility and achieve system redundancy, module failure can be detected in real time with a communication scan network, and then the output voltage of other modules will be changed by adjusting the switching frequency to maintain the same voltage as before the failure. Additionally, the proposed communication scan network includes the RS-485 interface of the MPPT series module and the CAN BUS communication interface with other subsystems’ communication for the PV micro-grid application system. Finally, a 6 kW MPPT prototype with a communication scan network is implemented and the proposed control method is verified for the PV system.

scholarly journals Technology of Quick-Frozen Flour Fish Culinary Products

2022 ◽  
Author(s):  
Valentina Pavlova ◽  
Irina Saenkova ◽  
Yulia Shokina ◽  
Grigoriy Shokin
Keyword(s):  
Mass Fraction ◽  
High Efficiency ◽  
A Priori ◽  
Cholesterol Content ◽  
Organoleptic Evaluation ◽  
Amine Nitrogen ◽  
Long Term Storage ◽  
Functional Product ◽  
Simulation Results ◽  
Priori Information

In this article, the results of the development of the functional fish culinary product “Thorny Skate and Cod Pie” are presented. A traditional recipe was used for making the yeast dough for the pie. The pie filling recipe was designed using Fuzzy Logic in the Matlab software package.Optimized parametersfor the selected sensory evaluation of the pie were calculated. On the basis of a priori information, key components of the filling (including the fraction of the fish components and skate meat) were chosen as the factors of interest. According to the simulation results, the optimal values werea 50/50 percentage for the first and the second factor respectively, and this providedthe maximum organoleptic assessment (five points on a five-point scale). The simulation results were compared with the results of the organoleptic evaluation of the pie made according to the optimized recipe, and their sufficient convergence was shown. The indicators of mass fraction of amine nitrogen and nitrogen of volatile bases was studied, as well as the microbiological safety indicators of flour fish culinary products, in accordance with the requirements of the Technical Regulations of the Eurasian Economic Union 040/2016 ”On the safety of fish products”. The results showed a high efficiency of the shock freezing of the semi-finished product, brought to semi-readiness, for long-term storage (120 days at a temperature no higher than minus 18 ∘C), without reducing the quality or safety of the pie. The product had a cholesterol content from 220 to 260 mg%, which allowed it to be classified as functional. The nutritional values of the product (mass fraction of protein, fat, carbohydrates, and amino acid composition) are presented. Keywords: thornyskate, functional product, pie with thornyskate and cod, shock freezing

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