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Voice coil motor (VCM) is a kind of direct drive motor widely used in multidimensional precision machining systems, which is of characteristics with high precision and high frequency response. This paper proposes a servo control system for a novel linear-rotary voice coil motor (LRVCM) which achieves a two-degree-of-freedom motion by one motor. Initially the basic structure of the novel LRVCM is described...
A novel Open-winding Permanent Magnet Synchronous Motor (OW-PMSM) drive system based on the five-leg inverter is presented to reduce the cost, volume and the switching loss of the inverter. Due to the common DC bus of the proposed five-leg inverter, the zero sequence current generated by the inherent 3rd harmonic of the phase back EMF flows through the phase windings and it leads to the weakness of...
The sliding mode variable structure controller is designed based on a kind of wheeled mobile robot. And this controller is applied to the trajectory tracking control of the robot. At first, the kinematic model is established based on the analysis of the wheeled mobile robot's motion characteristics. And the concrete sliding mode control algorithm is given based on the model. In order to reduce the...
The migration and segregation of Bi atoms in Cu/Sn-Bi/Cu solder interconnects under electric current stressing usually induce the formation of Bi-riched layers at the anode side, which can cause the failure of solder interconnects easily. In our study, the microstructure evolution of the eutectic Sn-Bi solder in a Cu/Sn-Bi/Cu flip chip solder joint and a right-angle Cu/Sn-Bi/Cu solder interconnect...
Test coverage is a effective approach of testing effectiveness and adequacy, which has positive impact on software reliability and defect coverage. The test coverage function describes the change of test coverage during the test procedure, and it is an important factor of software reliability models with test coverage. In this paper, the change of test coverage is represented by the generalized logistic...
The reduction of energy consumption in base stations becomes popular recently. However, it is difficult to reduce energy consumption under the constraint of Quality of Service (QoS). In this paper, we propose a novel energy aware control method to adjust the radius that the base station provide the service in wireless downlink systems, the optimal radius of the base stations provide service could...
Spelling errors of data entry is an important factor which influences banking data quality. Based on banking information system, we study non-word spelling errors occurring in the process of typing in with keyboard. The fingering of keyboarders and QWERTY international keyboard layout will be taken into account in the division of the letters. 26 letters will be divided into 5 types according to fingering...
The 2-D development process of water cannon is numerically investigated and visualized by a new type of integrated simulation technique. CFD (Computational Fluid Dynamics) analyze focused on the distribution of pressure, velocity and turbulence kinematic energy. Utilizing the governing equations for high-speed flow based on the LES-VOF model, a parallel computation is performed to clarify the detailed...
Internal faults in a wind driven generator can affect the quality of its output power, sometimes even the system's safety. However, the fault experiments are dangerous, thus this paper presents a Hardware-in-the-Loop (HIL) simulation system based on RT-LAB and DSP, which was applied to research the transient behavior of a doubly salient electro-magnetic wind power generator (DEWG) system and the control...
In wireless sensor network (WSN), the total energy is restricted, how to make good use of the limited energy resource is a very important aspect in the research of WSN. In this paper, a more reasonable energy consumption model is proposed: Optimal Energy Consumption Model (OECM). Under the new model of energy consumption, different network parameters can obtain different optimal clusters. It is different...
This paper describes the design of an observer-based gain-scheduling controller for the flight of an unmanned helicopter. Two linear quadratic integral controllers are designed for the linear models of the helicopter which is linearized in two operating points. Then the observer-based schedule controller is implemented, which is a linear fractional transformation between a fixed controller and a scheduling...
This paper exposes our online approach to real-time hydraulic simulation that could hardly be achieved through traditional optimization methods. The proposed approach includes a distribution model of SCADA nodes and an estimation algorithm of instantaneous node water flow. The SCADA model is used to analyze a complex water supply network into simple computation units, and the estimation algorithm...
In order to research wind turbine (WT) power generation in laboratory conditions, which do not have wind field environment, the power generation has to be imitated. This paper analyzes the operation principle of the WT, model the torque characteristics of WT by controlling the armature current of brushless DC motor (BLDCM). Then establish a strategy and dynamic model for the fixed-pitch wind turbine,...
An integral dynamic model of a wind power generation system containing non-linear wind models, a fixed-pitch stall-regulated wind turbine model, a mechanical transmission model, a multi-pole low-speed doubly salient electro-magnetic generator model, and an electric control model are established in this paper with MATLAB/Simulink. The mathematical simulation tool of the novel doubly-salient electro-magnetic...
In order to describe the dependent structure in the jump-diffusion risk model in non-life insurance, a Markov-modulated model is considered in this paper. By introducing an external continuous-time Markov process, the classical jump-diffusion risk model is extended to a Markov dependent one, in which the inter-claim time, the claim amount, the premium rate and the volatility of the diffusion process...
In order to measure the increasing complexity and dependent risk of nonlife insurance products and models, a class of the renewal risk processes with non-stationary and stochastic dependence properties are considered in this paper. By introducing an external continuous-time Markov process, the generalized Erlang(2) risk model can rationally characterize the dependent structure, in which the interclaim...
To the traditional ANC system, the noise reduction region is strictly limited around the error sensors within a certain range, but in terms of drivers, it is difficult to be installed in fixed error sensors around the human ear. In this paper, the idea of the virtual location of noise control will be introduced, and combined with the second error filtering algorithm. This method can effectively reduce...
Conventional PI regular is a simple control method that is widely applied in permanent magnet synchronous motor (PMSM) control systems. However, in most cases, it cannot meet the requirements of high performance control. In order to improve system robustness and response, this paper adopts sliding mode variable structure control strategy in the design of a double-loop controller (speed loop and current...
In this paper, a sliding mode control based on reaching law control (RLC) is proposed for permanent magnet synchronous motors (PMSM) drive system. The PMSM is a typical multi-variable nonlinear system with strong coupling. It is sensitive to load disturbances and changes of interior parameters, so conventional PID control can't meet the application requirements where high performance is required....
This paper presents the operational principles, design and transient analysis of a new three-phase 12/14-pole doubly salient electrical magnet (DSEM) generator for its application in direct-driven wind power generation. Design equations, finite element and dynamic analysis of the new generator are described. The 12/14-pole DSEM generator with constant self-inductance has lower voltage ripple compared...
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