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Based on magneto-hydrodynamics (MHD) theory, an air arc model is set up for the contacts and arc inducing plate at chamber inlet of a certain type of DC contactor and the dynamic behavior of the arc is simulated. The variation laws of arc length and the main conductive area migrating from moving contact to arc inducing plate were studied quantitatively under the influence of breaking speed and the...
Based on magnetohydrodynamics (MHD) theory, the model of air arc in arc extinguish chamber with metal splitter plate of DC contactor is set up. By assuming the arc plasma sheath and coupling loop equation in the calculation, the arc motion and the process of extinguishing the arc by splitting into series arcs by metal splitter plates are simulated. The reasons for the formation of air vortex on the...
The geomagnetic storms influence the operation of power systems, and do harm to the electrical equipment, and even lead to large-scale power outages. The purpose of this paper is to analysis the effect of geomagnetic storms on parallel transmission lines. In this paper, the coupled interference relationship of magnetic storms and transmission lines are analyzed. And the interference of magnetic storms...
With the development of power system and the constant attention to the security of equipment and personnel, fault diagnosis of grounding grid gets more and more attention. In this paper, a new fault diagnosis method for grounding grid based on damped least square QR-factorization algorithm is presented. Firstly, a magnetic field reconstruction method based on the magnetic field method is presented...
MEMS have been the hotspot in inertial measurements applications recently, due to their advantages of low-cost, high reliability, micro size, etc. But MEMS cannot be used in initial alignment alone because of its drift and noise. Since polarization navigation sensor's errors are not divergent, it can restrain divergence if polarization navigation sensor and MEMS become integrated navigation system...
A microstructural catastrophic model was achieved by adopting bifurcation theory and catastrophe theory. Moreover, a constitutive relation was established based on this model and creep equation. Theoretical analyzing shows that the model seems to capture well the observed features of soft clay compression behavior. During the compression, it is only the largest existing pores that collapse under a...
This paper proposed Multiple-Models Adaptive Estimation (MMAE) for Failure Detection and Identification (FDI) of aircraft components, i.e, flaps, landing gears. The MMAE FDI consists of parallel Kalman filters and each Kalman filter is constructed to represent a specific failure mode including the nominal mode. The Kalman filter residuals are post processed to produce the log-likelihood function values...
Focusing on adaptive control problems of nonlinear industrial processes, this paper proposes an modified iterative scheme of the closed-loop identification and design a δ-model adaptive controller based on plant-parameterization. The modification enables to identify the whole plant using only one coefficient and without the necessity of reducing the order of a new plant model. Moreover, instead of...
Arming to effectively control interelectrode gap of ECM, the 6-dimision forces and machining current are used as primary data of fuzzy controller which includes 2 inputs and 1 output. The interelectrode gap got from on-line monitoring and the initial setting gap compose deviation and deviation's variety, which are acted as input parameters of fuzzy controller, and the output of fuzzy controller is...
The enterprise group's value network will evolve along with the change of value units'numbers and their linked ways. According to the analysis of the hierarchy of enterprise group's value network, this paper constructs a structure evolution model for enterprise group's value network based on embeddedness of network. Searches for the evolution rule of enterprise group's value network from an example...
In this paper, the pure torsion vibration model of the planetary gear trains for the increasing gearbox is proposed. The influence coefficient method is used to deduce the system dynamic equations. The dynamic equations are solved considering the variable meshing stiffness and the constant meshing damping. Finally the non-linear dynamic characteristics are analyzed carefully.
The work studies the influences the friction effected the dynamic response of torsional model of gear pair. First, discrete harmonic balance method (DBM) is proposed new method to solve time-varying system dynamic equation; second, nonlinear time-invarying system (NLT) and nonlinear time-varying (NLTV ) system are analysised with friction. Finally, results show that friction is the significance nonlinear...
This paper presents a Flywheel Energy Storage System based on the Z-source inverter with maximum boost control. The proposed system can boost and generate a desired output voltage efficiently when low voltage of the generator is introduced due to the low flywheel speed. Z-source inverter has been identified to exhibit both voltage buck and boost capabilities in steady-state. In order to provide the...
Water hydraulic servo system is attractive technology for safety environment. This paper presents a design method of a robust rotational velocity controller of water hydraulic servomotor for the uncertain parameters and the load fluctuation. To overcome the highly nonlinearity of flow equation, we linearize and parametrize it. Considering the effect of uncertain parameter perturbation, e.g. load fluctuation...
This paper introduces the control strategy and method of non-linear dynamic inversion. Depending on the thought of dynamic inversion, the mathematical model of super-maneuverable aircraft is set up and the simulation curves are produced. Through analyzing the curves, we can draw out the feasibility and limitation of non-linear dynamic inversion.This paper introduces below contents :the feasibility...
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