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As Cross high order accumulation is able to depress non-correlative noise and correlative noise, MUSIC method based on cross-high-order cumulate is provided for diagnosing rotor broken-bar. It is difficult to detect faults feature component of the rotor broken-bar that it always hides behind the strong supply frequency component in the spectrum of the stator current. Simulation results were shown...
This paper introduced the research of aircraft maintenance virtual teaching and training system. The system is applied to solve the problems of traditional education technology. In order to realize this system, we chose system configuration, and design system hardware and software platform and structure according to system function requirement. We also discussed the outstanding advantages of the system...
The field oriented control technique is widely used in high performance motion control of induction motors. However, in real-time implementation, precise decoupling which requires accurate motor parameters can't be fully realized due to significant plant uncertainties such as external disturbances, parameter variations and plant nonlinear dynamic, this may deteriorate the dynamic performances of flux...
This paper introduces the partial discharge mechanism of power transformers and on such a basis, establishes an equivalent circuit model. In this paper, we take the partial discharge source as the equivalent of a second order differential circuit composed by resistors, inductors and capacitors, and the moment that partial discharge happens as the moment to power up the circuit. In the process from...
Harmonic wave is harmful to electric power system and equipment. In this paper a harmonic parameter estimation method based on ESPRIT (Estimating Signal Parameter via Rotational Invariance Techniques; ESPRIT) method is proposed. This method is able to depress noise and has better differentiation capability and estimation precision and stability. Design based on DSP of the harmonic detection test device...
The piezoelectric transformer (PT) as a pressurized component used in fuse all-electronic safety and arming device improves its security and reliability. The manufacturing materials and geometric parameters error of PT results in the error of the equivalent circuit model parameters. In order to effectively obtain accurate equivalent model parameters, the admittance circle is used to measure equivalent...
In order to transmit parameter information of the power battery management system on electric vehicles to the overall control unit timely and accurately, the paper comes up with a solution of dual CPU fast parallel communication. In the example of the Ni-MH power battery management system applied on some hybrid power electric vehicles, the paper elaborates the application principles, and operation...
Dissolved Gas Analysis (DGA) is a popular method to detect and diagnose different types of faults occurring in power transformers. In this paper, a improved Elman neural network is uesed to resolve the online fault diagnosis problems for oil-filled power transformer. Because of the uncertainty factors of the transformer faults, a method using fuzzy math theory to deal with the data of the neural network...
Due to the lack of withstand voltage of power electronic devices, and the voltage equalization among devices is hard to achieve when cascading the devices directly, the development of high-voltage switched reluctance drive has been blocked. Therefore, this paper proposes a novel high-voltage switched reluctance drive power converter structured by low-voltage power electronic devices. It introduces...
Introduce the structure and working principle of precision giant magnetostrictive actuator and establish the actuator system object transfer function model so as to design a suitable active disturbance rejection controller (ADRC). According to the model analysis, regard the actuator system as a first-order inertia object with dead time to construct second-order ADRC, use MATLAB for parameter tuning...
The formulas of output and ripple voltage from voltage multiplying rectifier are found in reference. The formulas are deduced on the condition of continuous simple harmonic waves. The corresponding formulas for input of pulse width modulating rectangle waves have not been found yet. In this study, pulse width modulating rectangle waves of high frequency are adopted as input of a voltage multiplying...
Drive technology and Control System of Electric Vehicle with TMS320LF2407A DSP as microcontroller are mentioned in this paper. The system takes permanent magnet syncronous generator as the driving motor, utilizing the direct torque control technology of SVPWM. Electric Vehicle are rearly driven by two wheels, which only needs to control one permanent magnet syncronous generator, and then it will be...
The present paper mainly aims at the numerically-controlled machine tool AC servomechanism, i.e. the permanent magnetism synchronous motor AC servomechanism's main feature, the application slip form changes the structure control strategy, improved the convention control policy to satisfy the request which with difficulty the high performance permanent magnetism synchronous machine actuated, enhanced...
In this paper, a new active magnetic levitation vibrator is studied, it is a mixed magnetic levitation system which is made up of permanent magnets and electromagnets, it can reach flexible damp vibration by using the mutual repulsive force between the magnets to provide levitating force. Based on the modeling of the system, According to the nonlinearity of magnetic levitation system of the vibrator,...
Aiming at the nonlinear characteristics of copper electrolytic system, this paper designs high-power thyristor electrolytic power supply current control system based on auto-disturbance rejection controller, the internal disturbance and external disturbance of system can be observed, and use them to offset the system using auto-disturbance rejection controller. It improves the stability of the electrolytic...
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