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Load-commutated inverters (LCIs) are the key starting device of wound-field synchronous motor. By detecting the rotor position and inputting a variable frequent current to the stator windings, the LCI can drive the motor from standstill to a given speed. Thus, rotor position detecting method comes to be the key techniques, but at the ultra-low speed period, the motor’s terminal voltage is too low to accurately sampling and is vulnerable to the interference, which brings risks to the variable frequency driving. In this paper, through analyzing the principles of LCIs and synchronous machine, a constant frequency electrical angle control methods is introduced to solve the difficulty of detecting the rotor position in the low speed period. A 98MW synchronous machine driven with an 18MW LCI are experimented in MATLAB and RTDS systems, the results show that the proposed control strategy can realize soft-start of the wound-field synchronous motor without detecting rotor’s position.

For high-altitude environment particularity, the device was designed for high-altitude correction. The equivalent stress analysis of particle system is researched to meet seismic requirementsneeds of automotive mobile devices. A new auto-switch is designed by improving the traditional tap-switch for automatic switching cable in the car. It is first used in a car as a automatically switch and greatly reduces the manual wiring workload. The field test results show that the device can assume a high altitude solar motion detector demand of the low voltage ride through (LVRT) .

The uniform and transparent Zn2TiO4series thin films were successfully deposited on medical glass slide by magnetron sputtering. The influences of the Zn-doped quantity and annealing treatment on films properties were investigated. Film structure, surface morphologies and optical properties were measured with XRD, SEM and UV-VIS transmittance spectroscope. The results show that the Zn-doped quantity and annealing treatment have influence on the absorption edges. The absorption edges of the films can increase 10nm after annealing treatment. The intensity of c-series ZnTiO3diffraction peaks is higher, which may be that the grain size is bigger and the crystallization is complete. The annealing treatment not only growing up grain size of composite films, but also the surface films have tiny crack phenomenon.

The influence of grating period and length of Photonic Crystal Fiber Bragg Grating on delay is investigated by using numerical simulation method and the coupled mode theory. The result shows that grating length and period has remarkable impacts on the delay. The maximum value of the delay can be obtained by parameters optimization, which is 52ps occurs at the grating length of 1.06cm.

Microstructures, morphologies and energy spectrums of oxidized films and their cross sections of plasma sprayed alloy coating Co-02 with Co-base, Co-04 whose matrix is nickel partially instead of cobalt and NDCo-02 with Ni-base substituting for Co-base were investigated. The result indicates that the coatings of these three kinds of alloys are white austenite base and Cr7C3 and Cr7(C, B)3 eutectic; Co-02 produces Cr2O3 oxidation protection film, and there were distinct areas with shortage of chromium in Co-04 and NDCo-02 coatings where CoCr2O4 and NiCr2O4 oxidation protection films were produced with spinel structure, these efficiently improved oxidation resistance; these three kinds of alloys have super oxidation resistance which increases according to NDCo-02,Co-04 and Co-02 orderly. The level of oxidation resistance was assessed.

The Photonic crystal fiber-based stimulated Brillouin scattering coupled equations are solved by the method of fourth-order Runge-Kutta formula and characteristics. Pulse delay and broadening of the Stokes pulse are studied in different PCFs under the same Stokes wave intensity and the characteristics in the small core PCFs for different ratio are investigated. The simulation results show that small core PCF has better time delay and the smaller the ratio is, the larger the time delay is, and the maximum pulse broadening factor is accordingly larger.

The mechanism of the orthogonal fluxgate is much more complex than that of the parallel fluxgate. Quantitative analysis on the orthogonal fluxgate has been seldom reported. In this paper, we analyzed the orthogonal fluxgate quantitatively. For an anisotropic soft magnetic material, the 3-D hybrid Jiles–Atherton/Stoner–Wohlfarth magnetic hysteresis model only provides semi-quantitative analysis. When the material of the senor is isotropic, a little modification was made on the 3-D hybrid Jiles–Atherton/Stoner–Wohlfarth magnetic hysteresis model, and the simulation after modification is more reasonable.

The electrodeposition can endow many properties for the devices, which plays an important part in the field of electronic manufacturing. The thin film transformer, fabricated with the usage of electrodeposition, expands the performance of traditional transformer, leading to many new characteristics and functions. The paper chiefly analyses the processing conditions of electrodeposition, including the solution composition, current density, PH value, temperature, stirring, power waveform, heat time, additives, etc. These factors bring significant influences on the behaviors of thin film transformer, for example magnetization, coercivity, compactability, density, ductility, wear resistance, corrosion resistance, porosity, brightness, molecular structure, crystal properties. It also presents some possible reasons about the different performances among the thin films. All these work provides beneficial exploration for the fabrication and optimization on the magnetic core of thin film transformer.