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The primary side feedback can stabilize the output voltage, and improve the service life of the equipment without using the secondary winding detection error signal. The topology of active filter and the improved method of primary side feedback were adopted. The performance of active EMI filter topologies was analyzed from insertion loss and equivalent circuit,the active filter with voltage sampling and current compensation was adopted. Through describing the mechanism of primary-side feedback of sampling knee point voltage, the small signal modeling of the converter in discontinuous current mode DCM) was carried out, and the compensation network was designed to ensure the stability. The simulation and experimental results show that the active EMI filter can effectively replace the traditional filtering method, and the original side feedback method can detect and correct the output voltage fluctuation to ensure the voltage stability. [ABSTRACT FROM AUTHOR]

BackgroundData-driven methods for power fault diagnosis heavily rely on the signal data quality of power sensors. The power systems in Tokamak fusion devices often operate in environments with complex electromagnetic field coupling, leading to the mixing of physical characteristic signals with a significant amount of inseparable noise in the collected data.PurposeThis study aims to mitigate the impact of noise on the final diagnostic results by proposing a multi-branch denoising network, termed Hierarchy Branch Denoising Convolutional Neural Network (HBD-CNN) that utilizes noise-resistant wavelet enhancement in conjunction with one-dimensional convolutional neural networks to accomplish power system fault diagnosis tasks under the influence of noise interference.MethodsFirstly, the signal decomposition function of discrete wavelet transform (DWT) was incorporated into the network layer of the convolutional neural network (CNN), and the optimization of the traditional 1D-CNN network structure was deepened alongside the more robust exponentially linear unit (ELU) for noise. Then, a data multi-level structure was constructed based on prior knowledge to leverage and couple it with hierarchical classification modules within the network, hence the generalization capability of HBD-CNN was enhanced. Finally, preliminary validation of the architecture of this model was conducted based on the simulated power supply dataset.ResultsValidation results show that the fault diagnosis accuracy for the power converter reaches 98.31% when the signal-to-noise ratio (SNR) is 10 dB. Even at an SNR of 2 dB, the accuracy remains above 92%.ConclusionsThe results of this study indicate that HBD-CNN demonstrates excellent fault diagnosis performance and potential under noisy conditions.

Output power and generation efficiency of switched reluctance generators are still to be improved. As the channel of energy conversion in the switched reluctance power generation system, the power converter is of great significance to the performance improvement of the entire power generation system. Output power and generation efficiency of the switched reluctance generator can be improved by the design of the power converter. Firstly, from the view of decoupling excitation voltage and generation voltage, a semiself-excited power converter and its control strategy were proposed to improve the excitation voltage and make the generation voltage lower than the excitation voltage. Secondly, the feasibility of the semi-self-excited power converter and its ability to prevent overcharging were verified through the simulation of startup and steady state operation. By using the simulation of variable speed and load, it was found that with the increase of speed and load resistance, the excitation voltage and generation voltage of the semi-self-excited power converter also increase, which could effectively improve output power and generation efficiency of the switched reluctance generator, especially at low speeds. Through single-phase fault operation simulation, it was verified that the semi-self-excited power converter has strong fault tolerance. Finally, the correctness of the theoretical analysis and simulation, as well as the effectiveness of the proposed semi-self-excited power converter and its control strategy were verified by experiments. [ABSTRACT FROM AUTHOR]

Copyright of Electric Drive is the property of Electric Drive 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 Journal of National University of Defense Technology / Guofang Keji Daxue Xuebao is the property of NUDT 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.)

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Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & 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.)

Copyright of Electric Drive is the property of Electric Drive 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 Drive is the property of Electric Drive 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.)

In order to improve performance of battery electric locomotive in coal mine, reduce energy consumption and improve work efficiency, a kind of control system of mine-used switched reluctance electric locomotive based on ARM was designed. The system uses control mode combing angular position control and chopped voltage control, adopts control strategy of torque distribution function, and achieves control of the battery motor vehicle combined with speed and current dual closed-loop system. The experimental results show that the system has small torque ripple, high efficiency, strong robustness and good performance of speed adjustment.

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & 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 Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & 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.)

The failure of normal excitation or freewheeling often occurs when power converter is damaged. The fault type was then analyzed in an asymmetric half-bridge converter, applied to a 12/8 switched reluctance drive (SRD). The analytical solution of the phase winding current was obtained by formula derivation under normal and fault conditions. Detailed discussions were presented about the amplitude changes of the DC bus current and its digital analysis results under different work conditions. The short-circuit and open-circuit fault detect method of transistors was also proposed, which was connected to the voltage pulse width modulation ( PWM) signals and the DC bus current. A model was used to build the pattern of the power converter of SRD system and the simulation has been implemented with mat-lab. The short-circuit and open-circuit fault simulation result of transistors are agreement with the theoretical analysis results. The detect method can identify the fault phase and determine the fault type. As a result,it has been proved that the method is effective. [ABSTRACT FROM AUTHOR]

To improve the synthetic performance of converters based on the present power electronics, this paper revealed that combining a power electronics switch circuit with a linear circuit can create a Switch-Linearity Hybrid Power Converter (SLH), whose operation scheme was briefly described. Two kinds of topologies of parallel connection and serial connection were listed as well as their features. The effect of SLH' low output resistance feature on the static and dynamic performances was explained. Comparing the SLH to a typical PWM converter plus LC filter unit, it presented the test data and the typical waveforms from the supply system and drive system in different load conditions. The results show SLH has good synthetic performances such as both high efficiency and optimal waveforms, adaptability to multi-kinds of loads and resistivity against load disturbances. [ABSTRACT FROM AUTHOR]