Abstract: A three-phase 12/8 pole switched reluctance motor drive system is introduced based on single chip microcontroller STC12LE5410AD and CPLD EPM240T100C5N. The design details of the controller are described in this application .To solve the nonlinear problem of switched reluctance motor, PI control algorithms are used to achieve the motor current control loop and speed control loop. The experimental results show that the hardware and software design of switched reluctance motor drive system are reasonable, and the proposed dual closed-loop control method is correct and feasible.
Abstract: A new 10T SRAM cell is proposed in this paper for simultaneously addressing the half select problem and improving the read/write stability. Without the half select condition, the proposed 10T cell allows efficient bit-interleaving to provide soft error rate protection and the dynamic power is also decreased significantly due to the reduction in the number of bitlines discharged and charged during the read and write operation. In the new 10T SRAM cell, one side of the cross-coupled inverters cuts off the pull up path or pull down path through adding two gated transistors according to the write ‘0’ or ‘1’ operation. It brings a great improvement for write stability without considering the half select disturb during the write operation. The simulation results indicate that the RSNM and WM of the proposed SRAM cell are enhanced by 130% and 58%, respectively, as compared to the conventional 6T SRAM cell in SMIC 65nm CMOS technology.
Abstract: In this paper, a novel compact microstrip lowpass filter is designed. The proposed filter which is etched on the 50 Ω microstrip line consists of four non-uniform 1-D microstrip photonic bandgap (PBG) cells with different cutoff frequency.. The demonstration lowpass filter with 2.2 GHz cutoff frequency is designed, fabricated and measured. The measurement results show that the band rejection effect is better than -20 dB from 2.8 GHz to 10 GHz, the insertion is less than 2 dB, and the length of filter is 5.6 cm long. Compared with the conventional filter, the proposed filter has smaller size. Meanwhile, it overcomes the problems of narrow stop-band and low harmonic suppression. Furthermore, the impedance matching is not need to be considered. This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. The best is to read these instructions and follow the outline of this text.
Abstract: PLL lock signal, there is contradictions in the capture time and capture bandwidth, also in the capture bandwidth and high signal-to-noise ratio. The article adopted the method of timely change bandwidth to resolve these conflicts, and used the VHDL to design a auto-change K module to adjust the bandwidth. Simulation results verify the validity of the module in the side of resolving conflicts between capture time and capture bandwidth, and capture bandwidth and high signal-to-noise ratio too.
Abstract: According to the electric potential of oblique five-needle electrodes (OFNE) in biological tissue, the discrete equations based on the indetermination linear current density were established by the boundary element integral equations (BEIE). The non-uniform distribution of the current flowing from five-needle electrodes to conductive biological tissues was imaged by solving a set of linear equations. Then, the potential generated by OFNE in biological tissues at any point can be determined through the boundary element method (BEM). It means that this method has an important referenced significance for computing the potential generated by OFNE in bio-tissue.
Abstract: In order to reduce the current consume of magnetic suspension bearing, the paper has brought forward a new low-power radial magnetic suspension bearing (RMSB), the bearing has a hybrid structure of permanent magnet and electromagnet, the upside suction force and downside repulsion force generated by permanent magnet can counteract the gravity of rotor, and the electromagnetic repulsion force generated by electromagnetic coil can adjust the dynamic position of rotor. Through the model simulation and analysis, the paper educes the calculation formula of eccentric force, gets the relationship between magnetic force and eccentric distance, gets the relation curves between the eccentric distance and the control current under the case of nonzero radial speed, and finally gets the minimum precise control current. This magnetic bearing has great effect and meaning in the no friction domain with the advantages of low power, simple control, etc.
Abstract: SLF waves travel in the air as vertical polarized vaves while as horizonal polarized vaves in the seawater,which have less attenuation than VLF waves. It propagates as lateral electromagnetic wave from seawater into air,whose energy will be concentrated on the interface. Comparisons of electromagnetic fields generated by vertical electric dipole in the air and horizonal electric dipole in the sea have been done.The results indicate that: (a) unit vertical electric dipole in the air is better than unit horizonal electric dipole in the sea. (b)when the receiver is below the boundary,the sources in the air provide stronger E field intensity than the sources in the sea do. (c)in the near field(1000km), underwater transmitting is hard to be achieved.
Abstract: A broadband power amplifier module based on GaN HEMT operating Ku band is designed. TGF2023-02 Chip of GaN HEMT from TriQuint is modeled first. And then the module consists of two stages amplifiers. The first stage amplifier is single-stage amplifier and the second is two-way combiner amplifier. Wilkinson power divider, DC bias circuits and microstrip matching circuits are simulated and designed carefully. Simulation results showed that the amplifier module exhibits a power gain of 7 dB, power added efficiency of 13.9%, and an output power of 16 W under Vds=28 V, Vgs=-3.6 V, CW operating conditions at the frequency of 15 GHz.
Abstract: This paper discusses the topology requirements of the small power photovoltaic grid-connected inverter,and introduces several typical topologies,moreover,points out the advantages and disadvantages,efficiency and applicable occasions of the various topologies. In this paper,a single-phase full-bridge grid-connected inverter topology(DC/AC) is designed. The soft-switching technology is employed on the topology for reducing switching loss. The topology can realizes zero voltage switching when the main switch turns on and turns off and zero current switching when auxiliary switch and the power diode turns on and turns off.The converter has higher efficiency than other topologies.