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Circuit noise is a critical factor that affects the performances of an MEMS gyroscope. Therefore, it is essential to analyze and suppress the noises in the key analog circuits, which are the main noise sources. This study presents an optimized front-end readout circuit and noise suppression methods. First, the noise analysis of the front-end readout circuit is carried out with theoretical derivation to clarify the main noise contributors. To suppress the output noise, an improved readout circuit based on the T-resistor networks is proposed, and the corresponding noise equation is derived in detail. In addition, the noise analysis of the critical circuits of the detection and control system, such as the inverting amplifiers, the first-order low-pass filters, and the first-order high-pass filters, is carried out, and the noise suppression strategy with the optimization of the resistances and is proposed. Taking the inverting amplifier as an example, the theoretical derivation is verified by measuring and comparing the output noises of different resistance schemes. In addition, the output noises of the gyroscope before and after circuit optimization are measured. Experimental results demonstrate that the output noise with the circuit optimization is reduced from 60 μV/Hz1/2 to 30 μV/Hz1/2 and the bias instability is reduced from 3.8 deg/h to 1.38 deg/h. In addition, the ARW is significantly improved from 0.035 deg/h1/2 to 0.018 deg/h1/2, which indicates that the proposed noise analysis and suppression methods are effective and feasible. [ABSTRACT FROM AUTHOR]

The study examines current trends in the development of the machine tool industry in Russia, in particular the introduction of multi-axis laser machining centers, and presents an overview of approaches to improving the efficiency of their production. It is shown that there is a need to improve data measurement and control systems of variable electric drives in order to reduce costs and increase reliability. A block diagram and a simulation model of a data measurement and control system for a variable electric drive characterized by low production costs and increased reliability are presented. [ABSTRACT FROM AUTHOR]

The consumption of high power and an extended start-up time are some of the major issues faced by piezoelectric energy harvesting. With this in mind, a control circuit with an extremely low power consumption of a few milliwatts is designed in this paper to energize heavy loads like wireless sensor nodes. A low-duty cycled self-powered control circuit, which works only at the maximum power point, is proposed in this paper. During a cold-start, optimum operative conditions can be achieved by this circuit. Moreover, a low power threshold at the input is sufficient to start the circuit. An additional piezoelectric transducer or a DC power supply is not required to operate this designed circuit. In terms of harvesting energy, performance enhanced by 320% can be achieved by this circuit when compared to the standard energy harvesting circuit when connected to a series-synchronized switch harvesting on an inductor (SSHI) with a large storage capacitor of 150 mF. An input power of 4.42 μW is enough for the circuit during cold-start and it consumes an ultra-low power of 0.3 μW. [ABSTRACT FROM AUTHOR]

We report the design and development of simple and economical Arduino-based four-channel data acquisition system with digital temperature control that is suitable for sensor parameter optimization involved in the search of appropriate chemiresistive gas sensing material for a particular gas. The developed system is capable of simultaneously capturing the data as well as controlling the desired operating temperature (up to 300 °C) of four sensing elements. This is achieved by employing sixteen analog and digital channels of the Arduino nano microcontroller. The sensing circuit is capable of recording the resistance changes from 20 kΩ to 5 MΩ at a rate of 15 kHz. The developed system has been tested rigorously, validated and demonstrated for its effectiveness towards investigating the gas sensing properties of chemiresistive NO2 sensors realized using ZnO nanowires. The present simple and low-cost alternative finds its application for developing the target specific chemiresistive sensors in particular for investigating the gas sensing properties of metal oxide semiconductors. [ABSTRACT FROM AUTHOR]

[Objective] To meet the training needs of metro drivers and maintenance personnel in studying metro control circuit principles, a MTCCS (metro train control circuit simulation system) is designed to address the issues of high coupling and complex control logic in metro control circuits. [Method] The overall structure of the MTCCS is introduced, and a logical control model of metro train control circuit is established. The depth-first path search algorithm is used to search for all valid paths in the network topology diagram, establishing the mathematical relationship between nodes, branches, valid paths and component states, and cooperating with relay linkage control to establish the logical control model. Taking the control circuit of Shanghai Rail Transit Line 15 as example, simulation testing is conducted on proposed control circuit simulation system. [Result & Conclusion] The proposed control circuit simulation system can meet the learning and training needs of metro drivers and maintenance personnel in understanding the principles of metro control circuits, posing practical value.

Background and Aims: The high prevalence of internet addiction (IA) has become a worldwide problem that profoundly affects people's mental health and executive function. Empirical studies have suggested trait anxiety (TA) as one of the most robust predictors of addictive behaviors. The present study investigated the neural and socio-psychological mechanisms underlying the association between TA and IA. Methods: Firstly, we tested the correlation between TA and IA. Then we investigated the longitudinal influence of TA on IA using a linear mixed effect (LME) model. Secondly, connectome-based predictive modeling (CPM) was employed to explore neuromarkers of TA, and we tested whether the identified neuromarkers of TA can predict IA. Lastly, stressful life events and default mode network (DMN) were considered as mediating variables to explore the relationship between TA and IA. Findings: A significant positive correlation between TA and IA was found and the high TA group demonstrated higher IA across time. CPM results revealed that the functional connectivity of cognitive control and emotion-regulation circuits and DMN were significantly correlated with TA. Furthermore, a significant association was found between the neuromarkers of TA and IA. Notably, the CPM results were all validated in an independent sample. The results of mediation demonstrated that stressful life events and correlated functional connectivity mediated the association between TA and IA. Conclusions: Findings of the present study facilitate a deeper understanding of the neural and socio-psychological mechanisms linking TA and IA and provide new directions for developing neural and psychological interventions. [ABSTRACT FROM AUTHOR]

Copyright of Urban Mass Transit is the property of Urban Mass Transit Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ZDJ9 AC five-wire switch control circuits exhibit the phenomena of arcing, burning, and oxidation of the first and second groups of strengthening contacts of the 2DQJ relays, resulting in poor contact of the contacts. Due to the fact that the first group of front contacts and the second group of rear contacts of 2DQJ relays are shared contacts, oxidation of these contacts can lead to loss of indication of a switch ; at the same time, there is a risk of instantaneous starting current striking and damaging outdoor diodes, which can also lead to loss of indication of a switch. The principle of the switch control circuits is analyzed, the circuit logic is adjusted, and the ZDJ9 AC five-wire switch control circuits are optimized to avoid loss of switch indication failure and improve the overall reliability of the switch equipment. [ABSTRACT FROM AUTHOR]

Copyright of Urban Mass Transit is the property of Urban Mass Transit Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] In the early operation stage of Jinan Metro Line 3, multiple sporadic high-speed circuit breaker closing failures are reported. To improve the reliability of train operation, it is necessary to optimize the high-speed circuit breaker control circuit in the traction system. [Method] According to the relevant closing command and the component status when a closure failure of the high-speed circuit breaker on Line 3 train occurs, and in accordance with the control logic principle of the high-speed breaker, the causes of the occasional closure failure are analyzed and the optimization measures are put forward. [Result & Conclusion] The causes of the occasional closure failure are that in the process of closure control of high-speed circuit breaker, the induced electromotive force generated at both ends of the high-speed circuit breaker coil makes the closing power insufficient, resulting in the failure closure of the breaker. The improvement measure is to connect freewheel diodes at both ends of the high-speed circuit coil to suppress the induced electromotive force generated by the above coil. With the above improvement measure, the closure failure of the high-speed circuit breaker caused by induced electromotive force never occurs again, and the reliability of train operation is effectively improved.

Circuit noise is a critical factor that affects the performances of an MEMS gyroscope. Therefore, it is essential to analyze and suppress the noises in the key analog circuits, which are the main noise sources. This study presents an optimized front-end readout circuit and noise suppression methods. First, the noise analysis of the front-end readout circuit is carried out with theoretical derivation to clarify the main noise contributors. To suppress the output noise, an improved readout circuit based on the T-resistor networks is proposed, and the corresponding noise equation is derived in detail. In addition, the noise analysis of the critical circuits of the detection and control system, such as the inverting amplifiers, the first-order low-pass filters, and the first-order high-pass filters, is carried out, and the noise suppression strategy with the optimization of the resistances and is proposed. Taking the inverting amplifier as an example, the theoretical derivation is verified by measuring and comparing the output noises of different resistance schemes. In addition, the output noises of the gyroscope before and after circuit optimization are measured. Experimental results demonstrate that the output noise with the circuit optimization is reduced from 60 μV/Hz1/2 to 30 μV/Hz1/2 and the bias instability is reduced from 3.8 deg/h to 1.38 deg/h. In addition, the ARW is significantly improved from 0.035 deg/h1/2 to 0.018 deg/h1/2, which indicates that the proposed noise analysis and suppression methods are effective and feasible.

Solar cooker has its own significance with an impact of substituting conventional source of energy for cooking. Solar cookers with electrical backup have proven the usage in off-sunshine hours to some extent. A cheaper and competitive PV and evacuated tube–based solar cooker with a control unit with incorporation of phase change material for energy storage were utilized without any interruption during off-sunshine hours for effective cooking. The proposed system has a control circuit connecting solar PV, DC output storage device (Battery 12V 75 AH), and DC-linked Nichrome heating coil. Three phase change materials, viz., palm oil, coconut oil, and paraffin wax, have been used in the system to extract and use the energy stored during sunshine hours in the materials. Figure of merit (F1) and figure of merit (F2) values for the system with the phase change materials have been found by doing experiments to find stagnation temperature without load and with load. The values of F1 (0.139) and F2 (0.42) for coconut oil are found to be effective with an energy efficiency of 38% compared to the other materials in the study with electrical backup. [ABSTRACT FROM AUTHOR]

Single-phase split induction motors consist of an auxiliary coil, a main winding and a centrifugal switch that separates the auxiliary coil. The starting torque of this motor is not large, and a resistance has to be added with the additional coil to increase the starting torque. Also, a mechanical centrifugal switch is used to disconnect the auxiliary coil. The motor also has another drawback that it has a constant speed. The aim of this research is to replace the added resistance with a current transformer that has a predetermined resistance and connected in series with the auxiliary coil such that it results in a maximum starting torque. In addition, it sends a signal to a control circuit that disconnect/connect the auxiliary coil through an electronic switch connected in series with the auxiliary coil. The connection/disconnection of the switch depends on the motor current not the motor speed to overcome the problem of switch false triggering due to motor overloading. The new technique increases the overall efficiency of the motor. MATLAB is used to simulate the system and verify the mathematical model. [ABSTRACT FROM AUTHOR]

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this work is to develop a mathematical model for studying the magnetic control field of a magnetically controlled ferrovariometer in a linear approximation. This problem is solved on the basis of a plane-parallel model. The solution is based on the method of secondary sources. On the basis of the developed mathematical model, a program is compiled in a highlevel language that provides input of initial data and their printing, calculation of the coordinates of secondary sources and calculation of the initial approximate value of the associated currents, as well as iterative calculation of the system of equations with a given accuracy. The described method and program make it possible to obtain an approximate picture of the distribution of the control field in the design of a magnetically controlled ferrovariometer and in the surrounding space, if the design can be represented by a plane-parallel model. Based on the field calculation, it is possible to perform a parametric synthesis of the control circuit design and evaluate its interfering effect on the surrounding electrical circuits.

Magnetorheological (MR) dampers are controlled energy-dissipating devices utilizing smart fluids. They operate in a fast and valveless manner by taking advantage of the rheological properties of MR fluids. The magnitude of the response of MR fluids, when subjected to magnetic fields, is of sufficient magnitude to employ them in various applications, namely, vibration damping, energy absorption, exoskeletons, etc. At the same time, predicting their response to arbitrary mechanical and electrical inputs is still a research challenge. Due to the non-linearities involved in material properties or the design of the solenoid used for activating the fluid modeling the relationships between the control circuit and the material's response is complex. Modeling studies can be classified into two categories. The parametric approach requires the knowledge of the internal material's properties and takes advantage of physics formulas to infer the I/O relationships present in the damper. For comparison, the non-parametric approach harnesses various data mapping techniques to describe the device's behavior. While the latter is more suited for design studies, the former seems ideal for control algorithm prototyping and the like. In this study, based on the so-called Support Vector Method (SVM), the authors develop a non-parametric model of the control circuit of an exemplary rotary MR damper. To the best of the author's knowledge, it is the first attempt at an SVM application for MR dampers' control circuit modeling. Using the acquired experimental data, the I/O relationships are inferred using the SVM algorithm, and its performance is verified across a wide range of excitation frequencies. The obtained results are satisfactory, and the current response of the MR damper is well-predicted. The model performance shows the potential for incorporating it into model-based prototyping and designing of MR control systems. [ABSTRACT FROM AUTHOR]

A ball screw type energy regenerative active suspension under fractional order PID control is proposed and studied in order to improve the vibration damping performance of the suspension. A mathematical model of the energy regenerative actuator is established, the energy recovery power at different frequencies is measured through experiments, and then the electromagnetic torque constant, representing the proportional relationship between the output torque and current of the motor, is calculated according to the experimental results. A mathematical model of the control circuit is established and the feasibility and the superiority of the fractional order PID control are verified by simulation and experiments. To achieve a better damping effect, the fractional order PID controller of the whole vehicle suspension system is parameterized using the Beetle Antenna Search (BAS) algorithm. The results showed that the mean energy recovery power of the actuator was about 3.5091 W at a vibration frequency of 11/6 Hz, and the electromagnetic torque constant of the motor was about 0.2885. The actuator control circuit was feasible, and the root mean square value of current deviation under fractional order PID control was 1.1158 mA, which was optimized by 9.40%, compared to the PID control. The BAS algorithm effectively realized the parameter tuning of the controller, and both the tuned PID and fractional order PID controllers, achieved optimization of suspension damping performance. The optimal value of the damping performance objective function under fractional order PID control was 0.3270, which was optimized by 62.93%, compared to the PID control. In addition, all suspension performance indices under fractional order PID control were optimized to a certain extent, compared with the PID control. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The work presents a control circuit for closing or opening an access way to a building, made in Xilinx. The control circuit allows the entry of a numeric code. Recognizing the established code determines the action of the mechanism for opening / closing the door. The numeric code consists of three digits, which can be identical, and which are entered from the switches on the development board in the programming state. You can increase the number of digits in the code by adding circuits identical to the existing ones. Switching to the standby state is done with a command on the development board, after which the numerical code can be entered again, the circuit passing into the operating state when the motor for opening the access path is commanded. The programming and actuation states are highlighted with an LED light signal. Entering the wrong code has the effect of blocking the drive circuit. [ABSTRACT FROM AUTHOR]

This article reports design, fabrication and analysis of a novel under-transistor (under-FET) in-hole thermal sensor diode structure. Being able to accurately monitor self-heating of individual transistor in-operando, the under-FET temperature sensor enables smart full-chip run-time thermal management with spatial resolution down to single transistor level. The in-hole thermal sensors were fabricated in a CMOS process and validated in measurements. The new chip level thermal management technique was demonstrated using a prototype power amplifier (PA) IC designed in a foundry 40nm CMOS. It opens a door for self-learning based full-chip real-time intelligent thermal management for future ICs.

Magnetorheological (MR) dampers are controlled energy-dissipating devices utilizing smart fluids. They operate in a fast and valveless manner by taking advantage of the rheological properties of MR fluids. The magnitude of the response of MR fluids, when subjected to magnetic fields, is of sufficient magnitude to employ them in various applications, namely, vibration damping, energy absorption, exoskeletons, etc. At the same time, predicting their response to arbitrary mechanical and electrical inputs is still a research challenge. Due to the non-linearities involved in material properties or the design of the solenoid used for activating the fluid modeling the relationships between the control circuit and the material’s response is complex. Modeling studies can be classified into two categories. The parametric approach requires the knowledge of the internal material’s properties and takes advantage of physics formulas to infer the I/O relationships present in the damper. For comparison, the non-parametric approach harnesses various data mapping techniques to describe the device’s behavior. While the latter is more suited for design studies, the former seems ideal for control algorithm prototyping and the like. In this study, based on the so-called Support Vector Method (SVM), the authors develop a non-parametric model of the control circuit of an exemplary rotary MR damper. To the best of the author’s knowledge, it is the first attempt at an SVM application for MR dampers’ control circuit modeling. Using the acquired experimental data, the I/O relationships are inferred using the SVM algorithm, and its performance is verified across a wide range of excitation frequencies. The obtained results are satisfactory, and the current response of the MR damper is well-predicted. The model performance shows the potential for incorporating it into model-based prototyping and designing of MR control systems.

This article presents a low-loss correction technique for a self-healing load-insensitive power amplifier (PA) using a modified two-tap six-port network, wherein the varying (complex) load is first compensated for its unwanted susceptance part, followed by adjustment of the transistor output stage to the ohmic load variation, by modifying its supply voltage and drive level. This two-step approach avoids the high-Q conditions that occur in tunable matching network solutions, which aims to correct for both the real and imaginary load deviations, such as providing lower insertion loss and voltage stress. Next, to facilitate a fully automated load mismatch correction without the need for calibration, a modified two-tap six-port network for impedance detection and control loop approach is proposed. As proof of principle, a prototype 900-MHz class-AB PA featuring the proposed correction technique, as well as, the six-port reflectometer and the control loop, has been implemented as a PCB demonstrator. Measurement results show that the self-healing load-insensitive PA in the events of load mismatch significantly improves the performance and approaches the 50- $\Omega $ performance. On a 2:1 VSWR 360° mismatch trajectory and driven by a 64-QAM 3.86-MHz signal, the PA achieves a linear output power of 22 dBm with only ±0.1-dB variation and better than −45-dBc adjacent channel power ratio (ACPR). [ABSTRACT FROM AUTHOR]

Dynamic simulation provides an efficient approach for improving the efficiency of parabolic trough power plants and control circuits. In the dynamic simulation, the possibilities and operating conditions of the plant are evaluated regarding materials, processes, emissions, or economics. Several studies related to the dynamic simulation of the parabolic trough technology are summarised and discussed in this work. This study is the first research that presents a thorough description of the advanced control circuits used in the solar field and thermal storage system of a parabolic trough power plant. This power plant was implemented using advanced process simulation software (APROS). The dynamic model was built based on the real specifications of the power plant. [ABSTRACT FROM AUTHOR]

Internal resistance is currently one of the most effective ways to achieve the performance improvement, control optimization, and on‐line fault diagnosis of fuel cells. In the fuel cell internal resistance test (FCIRT) system (FCIRTS), the alternating current (AC) disturbance signal is mainly achieved through the use of DC/DC converters or other expensive program‐controlled equipments, which are expensive and large, and it is not conducive to the commercial application of low‐cost FCIRTS. In particular, for the fuel cell vehicles based on dual‐source motors, the DC/DC structure is cancelled. Therefore, a new method should be used in the FCIRTS. To solve this problem, a low‐cost fuel cell AC disturbance signal control approach based on MOSFET high‐speed switch was proposed in this paper. In the approach, a circuit model of MOSFET high‐speed regulation was built, and the AC control of the fuel cells was achieved finally by simulation analysis and experimental verification. The proposed approach can not only independently control the AC components, but also save the system space and cost because of reducing reliance on DC/DC converters and dedicated equipments. Therefore, it is of great value to the development of low‐cost, high‐precision, and real‐time FCIRTS. [ABSTRACT FROM AUTHOR]

A ball screw type energy regenerative active suspension under fractional order PID control is proposed and studied in order to improve the vibration damping performance of the suspension. A mathematical model of the energy regenerative actuator is established, the energy recovery power at different frequencies is measured through experiments, and then the electromagnetic torque constant, representing the proportional relationship between the output torque and current of the motor, is calculated according to the experimental results. A mathematical model of the control circuit is established and the feasibility and the superiority of the fractional order PID control are verified by simulation and experiments. To achieve a better damping effect, the fractional order PID controller of the whole vehicle suspension system is parameterized using the Beetle Antenna Search (BAS) algorithm. The results showed that the mean energy recovery power of the actuator was about 3.5091 W at a vibration frequency of 11/6 Hz, and the electromagnetic torque constant of the motor was about 0.2885. The actuator control circuit was feasible, and the root mean square value of current deviation under fractional order PID control was 1.1158 mA, which was optimized by 9.40%, compared to the PID control. The BAS algorithm effectively realized the parameter tuning of the controller, and both the tuned PID and fractional order PID controllers, achieved optimization of suspension damping performance. The optimal value of the damping performance objective function under fractional order PID control was 0.3270, which was optimized by 62.93%, compared to the PID control. In addition, all suspension performance indices under fractional order PID control were optimized to a certain extent, compared with the PID control.

Background and Aims: The high prevalence of internet addiction (IA) has become a worldwide problem that profoundly affects people's mental health and executive function. Empirical studies have suggested trait anxiety (TA) as one of the most robust predictors of addictive behaviors. The present study investigated the neural and socio-psychological mechanisms underlying the association between TA and IA., Methods: Firstly, we tested the correlation between TA and IA. Then we investigated the longitudinal influence of TA on IA using a linear mixed effect (LME) model. Secondly, connectome-based predictive modeling (CPM) was employed to explore neuromarkers of TA, and we tested whether the identified neuromarkers of TA can predict IA. Lastly, stressful life events and default mode network (DMN) were considered as mediating variables to explore the relationship between TA and IA., Findings: A significant positive correlation between TA and IA was found and the high TA group demonstrated higher IA across time. CPM results revealed that the functional connectivity of cognitive control and emotion-regulation circuits and DMN were significantly correlated with TA. Furthermore, a significant association was found between the neuromarkers of TA and IA. Notably, the CPM results were all validated in an independent sample. The results of mediation demonstrated that stressful life events and correlated functional connectivity mediated the association between TA and IA., Conclusions: Findings of the present study facilitate a deeper understanding of the neural and socio-psychological mechanisms linking TA and IA and provide new directions for developing neural and psychological interventions.

A fundamental task in the dynamic simulation of parabolic trough power plants (PTPP) is to understand the behavior of the system physics and control loops in the presence of weather variations. This study provides a detailed description of the advanced controllers used in the power block (PB) of a 50 MWel parabolic trough power plant (PTPP). The PB model is achieved using APROS software based on the actual specifications of the existing power plant. To verify the behaviour of the PB model, a comparison between the simulated results and given real data is documented depending on a previous study, and the results indicate a reasonable degree of correspondence. The purpose of this study is to create reference models for the PB. Thereby, developers and engineers will have a better understanding of the state of the art of advanced control loops in these power plants. Moreover, these types of models can be used to specify the most suitable mode of operation for the power plant. In addition, this study gives an overview of dynamic simulation for the design, optimisation and development of power blocks in parabolic trough power plants.

This study describes the methodology and the basic procedure developed by the patent entitled New Configurations of DC ‐DC Converters of One Input and Multiple Outputs without Transformer and Power Converter that Apply Them. The invention is related with new configurations of DC ‐DC converters of single input and multiple outputs (SIMO), without a transformer, with a single power switch, and therefore a single control circuit, which results in a smaller size, lower weight and simplicity compared to other known SIMO DC–DC configurations. In a novel form, it comprises at least two converters which share the DC source, an inductor and the power switch. This is obtained by the combination of basic converters: step‐down (buck), step‐up (boost) and step‐down/step‐up (buck–boost) as ?uk converter, SEPIC (single ended primary inductance converter), Zeta, CSC (canonical switching cell) and buck ‐boost single‐inductor. A generalisation of the methodology developed in this invention allows to obtain modular converters with 2N, 3N, 4N and 6N outputs and single input, from N converter modules. The paper also relates to a power converter, comprising N (greater than or equal to 2) DC converters connected in parallel, whose control signals have a phase shifting of 2π/N radians. [ABSTRACT FROM AUTHOR]

Scanning electron microscopy (SEM) is a sophisticated observation instrument which is widely used to observe the surface topography of materials and study the microstructure and ingredient, it play a huge role in the research fields such as life sciences, materials science, chemistry and physics. The continuous development of scanning electron microscope technology makes it become an indispensable tool for scientific research institutions and enterprises to conduct high-tech research and routine analysis and testing. The purpose of this paper is to propose a new form of electron microscope control circuit and power drive circuit, so the scanning electron microscope can obtain higher resolution images to make up the lack of optical microscope resolution. At the same time, the new electron microscope control circuit can enhance the resolution of modern transmission electron microscope, stabilizing the accelerating voltage and the current through the lens. This paper mainly start with the working mechanism of the scanning electron microscope, analyzed the noise of the main control system and the influence of these noises on the imaging quality, and proposed measures to control noise by focusing on these three aspects: the control circuit, scanning circuit and power supply circuit, and classifies the power supply system of the control board to improve its anti-noise ability. At the same time, we use a high-speed DAC and a high-speed ADC to design scanning electron microscope high-speed scanning circuit and high-speed image data power driving circuit, and through a computer to control the control circuit and the power drive circuit. Finally, through the experimental verification, it is concluded that the design, development and system debugging of the control circuit and power drive circuit of the scanning electron microscopy are carried out. The flyback wide-voltage auxiliary power drive circuit of IRS2982S is expanded by adding a PNP triode emitter follower at each output level. The triode ZTX751 is adopted, and the index is PNP_60V_2A_200 degrees. Gain 200 levels, at least 10s of times amplification under small signal condition. The test results show that the noise of the image quality is well controlled, and the clear image of the sub-micron chip can be obtained by using the scanning electron microscope with this system. [ABSTRACT FROM AUTHOR]

Dynamic simulation provides an efficient approach for improving the efficiency of parabolic trough power plants and control circuits. In the dynamic simulation, the possibilities and operating conditions of the plant are evaluated regarding materials, processes, emissions, or economics. Several studies related to the dynamic simulation of the parabolic trough technology are summarised and discussed in this work. This study is the first research that presents a thorough description of the advanced control circuits used in the solar field and thermal storage system of a parabolic trough power plant. This power plant was implemented using advanced process simulation software (APROS). The dynamic model was built based on the real specifications of the power plant.

In induction motors, the spatial angle between the stator and rotor flux changes with the load, which creates more complex relations between currents, voltages and fluxes in the machine, as well as oscillatory dynamic responses. Controlling this space angle can ideally be carried out by converting the input stator current into direct i1d - component, responsible for the excitation flux and quadrature component i1q, responsible for the developed electromagnetic torque. This can be achieved by a vector control method that allows for a relatively simple solution to the problem of "coupling" between axes d and q, thus bringing the dynamic IM model closer to the separately-excited DC motor model. [ABSTRACT FROM AUTHOR]