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In this paper, we will study the optimal control problem of a system containing a differential integral (D-I) operator. We will deduce the necessary optimality conditions and apply it first to the problem of minimum energy to find the lowest energy for an electrical circuit containing a resistor, a coil and a capacitor (RLC circuit), and second to the problem of the minimum time to transfer electrical current in RLC circuit from one state to another in the shortest possible time. [ABSTRACT FROM AUTHOR]

The study aims to prepare modified glass fiber (mGF) through KH550 modified glass fiber (GF), aiming to enhance the mechanical and insulation properties of PA66 composites, and explore the effects of mGF content on the mechanical and insulation properties of PA66 composites. The results show that as the mGF content increases, the density of the composites shows a trend of first increasing and then decreasing. The tensile strength, elastic modulus, and notch impact strength all show a trend of first increasing and then decreasing. When the mGF content is 20%, the enhancement effect of various mechanical properties of PA66 composites is the strongest, with an increase of 13.38%, 19.23%, and 19.59% compared to the tensile strength, elastic modulus, and notch impact strength of pure PA66 composites, respectively. The electric field breakdown strength of PA66 composites shows a trend of first increasing and then decreasing under both DC and AC conditions. At the same time, the dielectric constant of PA66 composites shows a trend of first decreasing and then increasing, and reaches its lowest point at a dosage of 30%. The volume resistivity of PA66 composites shows a trend of first increasing and then decreasing, and reaches its highest value at a dosage of 20%, which is 3.34 x 1013 Ω·m. The mechanical and insulation properties of PA66 composites can be enhanced by adding 20% KH550 modified GF, which can be applied in the preparation of electrical circuit breaker materials. This material can be used as an electrical circuit breaker material. [ABSTRACT FROM AUTHOR]

Copyright of Fire Safety Science is the property of Fire Safety Science 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.)

Copyright of Earthquake (1000-3274) is the property of Editorial Office of Earthquake Journal 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.)

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock 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.)

Copyright of Electric Power Automation Equipment / Dianli Zidonghua Shebei is the property of Electric Power Automation Equipment Press 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.)

Laser Induced Plasma Assisted Ablation (LIPAA) has the advantages of economy, environmental friendliness, and high efficiency in the preparation of glass surface metallization. The feasibility of realizing metallized pattern circuit by using LIPAA process on glass substrate with metal copper as sacrificial target under nanosecond laser is studied. Therefore, firstly, the conductivity of metallized pattern circuit on glass substrate prepared by progressive scanning LIPAA is discussed in detail. In view of the disadvantage of the reduction of its conductivity caused by oxidation, the hydrogen reduction was further used to optimize its post treatment, and the circuit performance was analyzed by combining Scanning Electron Microscopy(SEM) and Energy Dispersive Spectroscopy (EDS), revealing the morphology characteristics and the change rule of resistivity of the surface of the glass metallized pattern circuit prepared by nanosecond laser LIPAA method. The results show that the metal layer on the glass surface can be directly ablated by the laser patterning removal process, and the fine patterned circuit can be prepared on the glass surface. At the same time, the chemical hydrogen reduction method can overcome the disadvantage that the metal layer oxidation seriously affects the circuit resistivity. The average resistivity after chemical hydrogen reduction is only 8.18 X 10-7Ω·m, which greatly improves the conductivity of the patterned circuit on the glass surface, shows broad application prospects. [ABSTRACT FROM AUTHOR]

Copyright of Wool Textile Journal is the property of National Wool Textile Science & Technology Information Center 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 frequency division phenomenon of the wireless power transfer (WPT) circuit in the electric vehicle wireless charging system under the premise of the optimal load resistance was discussed. In the optimized WPT circuit, by changing the value of the coupling coefficient (k) between the master and slave coils in the charging system, three zero reactance frequency (ZRF) points would be generated in the circuit, and then frequency division was generated. Through the adaptive frequency selection of the ZRF point, the output power of the entire circuit system can be maximized under the premise of high energy transmission efficiency. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Guangdong University of Technology is the property of Journal of Guangdong University of Technology 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.)

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays 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.)

Performing mass spectrometry (MS) in a low-vacuum environment not only substantially reduces the cost, size, weight and power of the instrument but also expands its applicability, making it is more suitable for field applications such as marine applications. As it is a complicated instrument, simulation is a critical step in the development process of a mass spectrometer. The Langevin collision model describes the interaction between low-energy particles. By introducing the Langevin collision theory to the simulation of low-vacuum ion motion, the movement of discrete ions can be more accurately described and the influence of different operational models on the performance of MS can be evaluated. Based on Langevin collision model, a low-vacuum simulation platform of cylindrical ion trap (CIT) was built in COMSOL Multiphysics. The influence of frequency of the radio frequency (RF) voltage V, amplitude of the radio frequency (RF) voltage ω and size of the ion trap r0 on the sensitivity and resolution of MS were investigated. The simulation results showed that by applying a high-frequency RF voltage, a spectral peak with a narrower width and a larger signal strength could be obtained and thus higher sensitivity and resolution were obtained. This is because when the frequency of the RF voltage is enhanced, the ion acquires more energy from the quadrupole within a unit time, which increases the moving velocity and enhances the collisional capability of the ions. When ω increases, in order to keep Mathieu parameter q unchanged, V must be increased with the square of ω or decrease r0 proportionally. The value of V is determined by the electric circuit, and it is very difficult to increase it significantly. Moreover, a high voltage can cause discharge. Therefore, from this perspective, in order to use a larger RF frequency ω, the size of the ion trap r0 must be reduced. Thus, it is concluded that by increasing the frequency of the radio frequency voltage while reducing the size of the ion trap, mass analysis can be conducted under a low vacuum. Additionally, the results was applied to experiments and obtained excellent spectral graphs of organic compounds under a maximum pressure of 2 Pa in another paper, which proved the effectiveness of the conclusions obtained from the simulation. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Henan University of Science & Technology, Natural Science is the property of Editorial Office of Journal of Henan University of Science & Technology 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.)

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management 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.)

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control 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.)

Copyright of Computer Measurement & Control is the property of Magazine Agency of Computer Measurement & Control 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.)

Timed-release encryption( TRE) is a cryptography that studies the problem of sending information into the future,it can solve many practical problems to construct a feasible and safe TRE. This paper proposed a scheme based on the research of indistinguishability obfuscation and TRE. This scheme encapsulated the sender’s encryption and receiver’s decryption by a circuit and obfuscated this circuit by an indistinguishability obfuscator. It could make great use of the time of obfuscators obfuscate circuits,simplified the scheme and improved the security of this scheme. Finally,this paper proves the correctness and security of this TRE scheme. [ABSTRACT FROM AUTHOR]

Parasitic inductance has larger influence on Silicon Carbide devices with the increase of switching frequency. This limits full utilization of performance advantages of low switching losses in high frequency applications. By combining theoretical analysis with experimental parametric study, a ma thematic model considering parasitic inductance is developed for the basic switching circuit of SiC MOSFET. Main factors which affect the switching characteristics are explored. Moreover, a fast-switching double-pulse test platform is built to measure individual influence of each parasitic inductance on switching characteristics and guidelines are revealed through experimental results. Due to limits of practical layout in high-speed switching circuits of SiC devices, the matching relations are developed and an optimized layout design method of parasitic inductance is proposed under a constant length of the switching loop. The design criteria are concluded based on the impact of parasitic inductance, which provide guidelines for ayout design considerations for SiC-based high-speed switching circuits. [ABSTRACT FROM AUTHOR]

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic 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.)

Copyright of Piezoelectrics & Acoustooptics is the property of Piezoelectric & Acoustooptic 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.)

People are paying more and more attention to the mind map and the concept map at home and abroad, because they have great potential value. The mind map and the concept map are applied to the curriculum teaching of electric circuits, teachers use them to design, organize and implement the teaching. They can be integrated to the modernized multimedia teaching courseware. The mind map is conducive to constructing knowledge network, and the concept map is helpful for the representation of the concept. Thus the teaching is made lively and dynamic, and the efficiency of teaching and studying is raised enormously. All in all, the teaching effect is enhanced more efficiently. More importantly, the mind map can cultivate students' ability of logical thinking and divergent thinking, and can effectively inspire the potential of the brain's memory and creativity. [ABSTRACT FROM AUTHOR]

In order to upgrade the stepping motor controller, the application of S3C2440A in human-computer interaction of stepping motor controller was discussed in detail. The special touch-screen interface and LCD controller in S3C2440A could connect with touch-screen and LCD directly. Based on introducing the architecture of stepping motor controller, circuits among S3C2440A, touch-screen and LCD were given, and related application programming design was analyzed deeply. The information of touched point on touch-screen was sampled by combining interrupting mode and X/Y coordinate sequential conversion mode, meanwhile three-points calibration method was introduced. At last, sampling codes were given. The scheduling, buffer setting and displaying data format of LCD controller were analyzed based on 320X240 TFT LCD. Also, the applied programming codes were given. At last, the above codes were executed in practical system. Result shows that connection between S3C2440A, touch screen and LCD is convenient. So the hardware-design and load of the system could be predigested with this architecture. This system runs well in the application. [ABSTRACT FROM AUTHOR]

A variety of heterogeneous electronic equipment were difficult to integrated with each other in intelligent home system, this paper adopted a universal plug and play standard to integrate the service robot into the intelligent home system, emphatically introduces the new derivative service. Firstly, it introduced the details of UPnP standard and service robot Rovio. Then, it developed a PC application program as the virtual bridge between the service robot and intelligent home network, and formed a control circuit to control the service robot to provide service for intelligent home system. Finally, it used some practical operation to test the performance of the UPnP Rovio virtual bridge, and demonstrate the possibility of the integration between service robot and intelligent home network by the practical services, such as path tracking, rubbish monitoring and so on, especially, the advanced services show that the huge potential benefits are expected. [ABSTRACT FROM AUTHOR]

The lifespan of the output filter electrolytic capacitor in general lighting LED power supply doesn't match LED's long lifespan. In this regard, this paper proposed the LED driver circuit based on Buck with active ripple compensation. In the circuit, the active ripple compensation branch was used to replace the output filter electrolytic capacitor to offset the inductor ripple current, so that the LED array can obtain a constant DC and achieve the ideal drive state of the LED. In order to reduce the losses of the ripple compensation branch, the peaks and valleys of the inductor current must be controlled and the hysteresis current control can effectively meet that requirement. The LED power supply based on Buck with active ripple compensation and hysteresis current control was designed and made which output power was 30 W. According to the simulation and experiment results, the proposed new power supply is feasible. [ABSTRACT FROM AUTHOR]

Based on the study of the duct overheat detection system of civil aircraft in existence, its shortage is pointed out. Therefore a modified overheat detection system is designed with heat-sensitive property material and combinational circuits, which owns the capabilities of alarm and location for the high-temperature and pneumatic duct overheat part. Some interrelated optimization methods are put forward as well. Also, the overheat detection experiment platform is built and the designed detection system is validated experimentally. The influences of the overheat length and the response time of internal air temperature on the system are conducted. The research results show that the response time of the detection system decreases with the increase of temperature of the internal air and the response time remains approximately constant when the temperature reaches a certain value. Meanwhile the response time of the detection system decreases with the increase of overheat length. [ABSTRACT FROM AUTHOR]

A design method of magnetic circuit in a disk-type permanent magnetic micro-generator is proposed, including modeling, theoretical analysis, simulation and experiment. The effects of the structural parameters on magnetic flux density in the magnetic gap and the constraint relations among the parameters are discussed. The calculation method of magnetic flux density in magnetic gap and the optimization scheme of structural parameters of micro-generator are studied. The design method of magnetic circuit in the planar permanent magnetic micro-generator is summarized. Errors between the theoretical calculations and experimental results are less than 7%, which verifies the rationality and accuracy of the calculation method of magnetic flux density. [ABSTRACT FROM AUTHOR]

Using an asynchronous motor as controlled object, the new ADRPI soft-switch three-phase inverter circuit and the actuation control circuit diagram of inverter electric circuit were designed, and based on many experiments for inverter circuit design and driving control circuit the concrete improvement measures were proposed, using the new type of soft switch inverter circuit and the selection and design of the drive control circuit component parameters. The experimental results showed that pinnacle impulse from the inverter circuit output signals of ADRPI soft-switch invertor circuit was restrained and the inverter circuits output characteristic was improved, so the quality of output current of inverter has been obviously improved. [ABSTRACT FROM AUTHOR]

OPC Server Client, shared variable, Datasocket data binding and Distributed System Manager in four different ways to realize the data communication between the FX2N-48MR PLC and PC based on OPC technology. Described the main features of the of OPC technology, Datasocket technology, LabVIEW and DSC modules. In the osciilation circuit experiment, for example, verify the feasibility of the data communication of the four ways. Experiments show that these communication method with simple operation, high reliability. [ABSTRACT FROM AUTHOR]

In order to solve the problem of big difference between simulation process and actual application process this paper takes the signal filtering in electrical circuit system as an example, to present a design method of digital filtering system. Using relevant modules provided by the software of SIMULINK/SIMSCAPE, some electrical circuits are built, and combing some programming skill, triggered subsystem from SIMULINK modules is used to simulate the process of periodical sampling, periodic calculation of difference equation. Furthermore, relevant programming idea is introduced by the implement of a first order low pass filter. Finally, simulation results show the efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

A new direct peak DC-link voltage control strategy of Z-source inverter (ZSI) is proposed. For ZSI, the peak DC-link voltage is the actual voltage fed to the inversion stage. Controlling the peak DC-link voltage at the constant level can effectively decrease the voltage stress and simplify the design process of the inversion stage. A direct peak DC-link voltage detection method is developed with a simple sampling circuit, and then controlled directly. Therefore, the constant peak DC-link voltage can be achieved in different input and load conditions. The peak AC output is calculated in real-time by sampling the AC phase voltage, and it is controlled to the desired value without steady-state error. With the proposed direct peak DC-link voltage control and the peak AC output control, both the peak DC-link voltage and AC output are controlled to a desired level under different input and load conditions. Experimental results demonstrate the feasibility of the proposed control strategy. [ABSTRACT FROM AUTHOR]

With regard to the electromagnetic interference and power loss generated in the operation of the switches in switched reluctance motor drive ( SRD ) system, the paper proposed a converter with a new kind of capacitor divider parallel resonant DC link( CDPRDCL). The converter was to realize the zero-voltage-turn-off of the phase switches by connecting one buffer capacitor to each switch in conventional asymmetric inverters; and to realize the zero-voltage-turn-on of the phase switches, and the soft operation of the resonant switches, by adding a resonant link containing, as the main components, two inductors and one capacitor and through reasonably controlling the resonant switches in this link. The required condition for soft-switching was obtained by analyzing the working principle and operation process of the circuit. The soft-switching converter with such a resonant link has a larger effective interval and a lower power loss,thereby enhancing the efficiency and performances of SRD. Finally,the validity and efficiency of the converter are verified by MATLAB simulation. [ABSTRACT FROM AUTHOR]

This paper firstly expounded the principles of EHW and introduced the current status at home and abroad. Then it presented the important steps of EHW. Lastly it put forward the existing problems and the improvement directions. Fault self-repair based on EHW will have bright prospect and great value in engineering application [ABSTRACT FROM AUTHOR]

To solve the problems of complex fault location process and heavy workload before test using traditional large-scale circuit fault diagnosis methods in the multi-fault conditions, this paper presented a new approach for fault diagnosis using group decomposition. Low dimensional fault eigenvectors could be acquired by decomposing the large-scale analogue circuit in accordance with its topological property and group decomposition criteria. Based on ideas of pattern recognition, neural network which had highly parallel classify capability was selected as classifier and wavelet function which had fast convergence property was selected as hidden layer's transfer excitation function. The simulation results show that this method can achieve fast fault feature vector classification and fault diagnosis results. Comparing with the existing multiple-test-condition (MTC) method and intersection tearing method, this approach has smaller amount of work before test, fewer diagnostic times, less computation, better capability of diagnosing multiple faults and stronger engineering practicality. [ABSTRACT FROM AUTHOR]

The nonlinear circuit design of a neuron model with adapting feedback synapse was performed. It realizes the nonlinear dynamical phenomenon of switching from the coexisting chaotic attractors to a connected chaotic attractor. The dynamical behaviors of the designed circuits are correct by Electronic Workbench software. [ABSTRACT FROM AUTHOR]

To deal with the problem of the effectiveness of the traditional evolutionary design algorithm for polymorphic circuits, a new design algorithm based on dynamic evaluation method is proposed. The fitness evaluation expansion is presented to separately evaluate the circuit under different modes, while the comparison and selection is used to configure the optimal structure of the circuit in the stage of fitness evaluation, thus the loss of potential solution is avoided. The evolutionary design experiments for Multiplier/Sorter and Majority/Parity circuits are conducted by combining the polymorphic gate with conventional gate. The experimental results show that compared with the conventional algorithm, the iterations of evolution is decreased by 31.2%-77.7% and the success probability is increased by 11%-52%. The proposed algorithm has the less iterations and the higher probability of success, thus a better effectiveness. [ABSTRACT FROM AUTHOR]

The mode offset angle identification is a key step of the balance process of the cupped wave gyroscope. The rela- tionship of vibration mode shape and output signal of the piezoelectric electrodes in cupped wave gyroscope are studied, and according to the feature that the angle between the inherent axes of the two neighboring work modes is 45°, a fast identifica- tion method for mode offset angle of cupped wave gyroscope based on output signal detection of the piezoelectric electrodes on resonator is put forward. By this method, the negative effect on vibration mode test caused by difference of vibration transfer efficiency of each piezoelectric electrode can be eliminated, the mode offset angle can be identified accurately, and the propor- tion between each piezoelectric electrode's vibration transfer efficiency can be worked out. The mode offset angle of the cupped wave gyroscope prototype is identified by using the fast method, and the result is compared with the mode shape test data from laser Doppler vibrometer. The result of the experiment proves that the fast method has following advantages: sim- ple circuit, low time-cost, accurately calculation and high identification efficiency of mode offset angle. The research work provides reference for the balance process and control circuit design of the cupped wave gyroscope. [ABSTRACT FROM AUTHOR]

Based on the conventional lumped parameter equivalent circuit model, the electrical characteristics of piezoelectric transformers (PTs) in series-parallel connection were analyzed using Y-parameter matrix. The voltage gain, output power and efficiency as function of parameters and the number of connected piezoelectric transformers were derived and simulated. And the electrical characteristics were simulated by using radial-mode vibrating PTs. Two piezoelectric transformers at the voltage gain of 0.081 6 with input and output parts isolated were tested. After series-parallel connection the voltage gain was reduced to 0.0406 on the same load of 20 ∩. The computed and experimental results verify the fact that the series-parallel connection of piezoelectric transformers can enhance the voltage step-down ratio. Series-parallel connected piezoelectric transformers can realize voltage step-down. [ABSTRACT FROM AUTHOR]

According to the characteristics of bidirectional and reversible effect of multiple piezoelectric effects in single piezoelectrics, theoretical analysis is carried on for multiple piezoelectric effects realizing displacement self-sensing of piezoelectric actuators. Thus, one to one correspondence between multiple converse and multiple direct piezoelectric effects is illustrated, and the feasibility of separating electric displacement caused by multiple direct piezoelectric effects from dielectric electric displacement is analyzed. Through a referenced capacitor combined with current integration and differential proportional operational circuit,a decoupling method which is easier for practical engineering application than electric bridge circuit is obtained. The experiments justified the method through a PZT-5 stack actuator. Meanwhile,linear coefficient of the secondary direct piezoelectric effect is obtained for PZT-5 stack. And the influence of tertiary piezoelectric effect on resolution and precision of piezoelectric self-sensing actuators is further analyzed. The study results can provide a new approach for the performance improvement of self-sensing actuators. [ABSTRACT FROM AUTHOR]

The article analyses the reliability of the operating mechanism of circuit breaker based on FMEA, constitutes standard forms of statistics FMEA, analyses and researches the reliability of the operating mechanism through the standard forms. According to result analysis of FMEA, Proceeding the reliability design of system key parts and the reliability of increasing experiment. [ABSTRACT FROM AUTHOR]

Electromagnetic interference(EMI) of the harmonic frequency can be effectively reduced by frequency modulation, which is spreading single harmonic energy into a certain frequency band by modulating the constant clock frequency. After studying and balancing three modulation profiles Of frequency modulation technique, a circuit based on triangular profile in time is proposed. Test results showed that the peak amplitude of the conducted EMI of AC/DC switch-mode power supply (SMPS) decreased by about 3.5~5.7 dB with the new circuit. It helps to ease the pressure of diminishing the EMI on the system level of SMPS. [ABSTRACT FROM AUTHOR]

A novel sensor with detection and signal processing circuit of micro-magnetic physical fields is proposed. The approach is based on the physical characteristics of Fe-Co-Si-B amorphous wires, and the theory of giant magneto-impedance effect and resonant circuit. With improvement in forms and algorithms of magnetic sensor, the circuit ensured the characteristics of high sensitivity, high detection precision, fast response and small power consumption. Experiments showed that the measurement range was 0~1 T and resolution 100 nT. Using the micro-magnetic sensor, the static magnetic field around a tank was analyzed, which improved the accuracy of the model. [ABSTRACT FROM AUTHOR]

The sensorless control method of brushless DC motor is introduced and an inverter system based on M16C28 is presented. M16C28 is the heart of this design and it consists of many circuits, including MCU central control unit, rotor position detection circuit, inverter driver, DC - BUS voltage and current detection, motor protection, communication interface circuit, and so on. The sensorless control principle of brushless DC motor is expounded from many aspects such as PWM drive signal generation, PWM signal' s output modes and motor induced voltage. The hardware circuits of brushless DC motor control are introduced, at the same time, the software algorithm and module functions are explained. It is presented that this sensorless drive design for brushless DC motor has low cost, high efficiency and broad scope of motor speed adjustment. [ABSTRACT FROM AUTHOR]

The rule of charge time of high-voltage circuit in the electronic safety and arming system(ESA) of fuzes is studied. Adopting discrete time-domain method to set up the mathematical model of high-voltage conversion circuit, and analyzing the influence of frequency, duty cycle, primary inductance, different turns ratio parameters how to affect high-voltage convertion circuit charging time. Simulation and experiment results express the mathematical model can reflect the variational trend of actual circuit, and the shortest charge time is 75 ms when the frequency of dynamic signal is 100 kHz and the duty cycle 0.55. [ABSTRACT FROM AUTHOR]

A feedback control corcuit is presented to solve the problem of electric isolation between the input and output of high voltage feedback circuit used in the ESA of fuze. Sampling voltage from the original side of high voltage transformer can control the charge voltage of high voltage capacitance and solve the problem of electric isolation, and adopting filter to solve the problem of spike voltage in high voltage transformer. Simulation experiment results showed that the voltage of capacitance could be controlled to 2 kV, the input and output of high voltage transformer was effectively isolated and the control circuit worked reliably. [ABSTRACT FROM AUTHOR]