Applied Mechanics and Materials Vols. 494-495

Abstract: In this paper, short-range communication technology, power transmission or for certain control devices, has developed an easy to monitor and control the local portable handheld device, meet people based portable monitoring requirements, first, short-range wireless communication module design, followed by the portable handheld device and GIS controller design, and ultimately lower PC and wireless communication between machines. To achieve the purpose of the portable control.

Abstract: This paper presents an improved switched inductor (SL) Z-source inverter, which is derived from the classical SL Z-source inverter. To decrease the input current ripple, the proposed inverter employs an LC boost impedance network between the source and Z-source network. Compared with the SL Z-source inverter, the proposed inverter has the constant input current from the source and increases voltage boost inversion ability significantly. Topology analysis in the steady state is given, and simulation results verify the theoretical analysis results.

Abstract: The cascaded multilevel convertor has the following advantages: simple structure, less harmonic, and less switching loss. It also can easily achieve high voltage and large power capacity. However, due to the structure of cascaded, the number of the device increases with the increment of capacity, meanwhile the reliability of the system reduces. Based on the cascaded multilevel systems possible failures and the characteristic of carrier phase shift modulation, this paper proposes a fault diagnosis method suitable for the cascaded multilevel system. Firstly, the paper introduces the basic principle of the proposed approach, and then it deduces the major implementation steps, finally the correctness and reliability of the method are validated by the simulation.

Abstract: In this paper, the BPJA-1200/6K mine-used high-voltage frequency converter designed and developed with Power Flex7000 is introduced. How to replace the fluid coupling used in original belt conveyor system with the converter to achieve the purpose of speed regulation by frequency variation as well as long distance driving are discussed. At the same time, the composition of the centralized control system for the belt conveyor is discussed and the speed regulation strategy and the main control functions are introduced. The converser system has been applied to a mine belt conveyor and the running results are better.

Abstract: Some key technical problems encountered in making mine-used explosion-proof and intrinsically safe high-voltage frequency converter are researched and discussed. The inverter integrates common-mode voltage rejection of DC reactor, deionized water circulation cooling technology, selective harmonic elimination technology, explosion-proof technology, adopts advanced Power Flex7000 with good speed regulation performance. The circulation water cooling device presented in this paper has high cooling efficiency, small size, lower operating noise and good water-saving effect. This inverter has actually run in Huainan coal mine and the application effect was better.

Abstract: This article takes non-on-board high frequency charger of pure electric vehicle for research subject, based on the overall structure design, aimed at the deficiency of constant current and constant voltage charging, put forward constant current first, constant voltage afterclose-loop control charging tactics, and analyses charging principle and process in deep, has a certain amount of theoretical research and practical application value.

Abstract: A novel topology structure of supercapacitor energy storage converter (ESC) is presented with two cascaded bidirectional DC/DC converters connected to a bidirectional DC/AC converter. It can promote the energy utilization rate of supercapacitor and improve the ability of powering unbalanced and nonlinear loads. The effect of the midpoint voltage fluctuation of the cascaded connected DC bus capacitors on output voltage is analyzed, followed by the influence mechanism unbalanced and nonlinear loads. The control strategy to restrain the unbalance and zero sequence harmonic is proposed. The theoretical analysis and the proposed method are verified through simulations and experiments on a 100kVA supercapacitor ESC prototype.

Abstract: This template explains and demonstrates how to prepare your camera-ready paper for a flywheel energy storage system discharge circuit based on PWM control technology is introduced. The main circuit structure is given and the working principle is analyzed. On that basis, the detailed design method of high-frequency transformer, PWM control circuit and the driving circuit is introduced. The discharge system with the output power of 480W and the output voltage of +48V is designed by applying the method and the experimental waveforms are provided.

Abstract: According to the nonlinear dynamic mathematical model of the three-phase AC permanent magnet synchronous servo motor (AC-PMSM), the inner disturbance and outside disturbance can be observed with the extended state observe (ESO), and use it to offset the system. The result of simulation and experiment indicate the control system of PMSM has better dynamic and robust characters by using auto-disturbance rejection controller.

Abstract: Harmonics always have a negative impact on control precision and grid quality. It has been found out that harmonic distribution is very germane to carrier frequency. Based on the analysis of conventional SVPWM, in this paper a chaotic carrier frequency SVPWM strategy is proposed, where the theory of chaos is applied to generate the desired random source for SVPWM carrier frequency. Simulation result proves that chaotic carrier frequency SVPWM can not only improve the waveform quality, reduce the low-order harmonics, and also flatten the high-order harmonics effectively.