Automatic bearing fault diagnosis of permanent magnet synchronous generators in wind turbines subjected to noise interference

Abstract

An automatic bearing fault diagnosis method is proposed for permanent magnet synchronous generators (PMSGs), which are widely installed in wind turbines subjected to low rotating speeds, speed fluctuations, and electrical device noise interferences. The mechanical rotating angle curve is first extracted from the phase current of a PMSG by sequentially applying a series of algorithms. The synchronous sampled vibration signal of the fault bearing is then resampled in the angular domain according to the obtained rotating phase information. Considering that the resampled vibration signal is still overwhelmed by heavy background noise, an adaptive stochastic resonance filter is applied to the resampled signal to enhance the fault indicator and facilitate bearing fault identification. Two types of fault bearings with different fault sizes in a PMSG test rig are subjected to experiments to test the effectiveness of the proposed method. The proposed method is fully automated and thus shows potential for convenient, highly efficient and in situ bearing fault diagnosis for wind turbines subjected to harsh environments.

The Design of Intelligent Charger of Electric Vehicle Under the Control of Microcontrollers

“…Out gassing amount generally refers to the total amount of gas produced by anode and cathode in the complete charging process of electric vehicle battery under standard atmospheric pressure, with the unit of liter and out gassing. The out gassing rate refers to the total amount of gas produced by anode and cathode in a certain charging link under a standard atmospheric pressure [15], and the unit is liter/minute. In order to improve the protection for battery and extend the working time of battery, reducing the out gassing amount is a very important work.…”

Two-Dimensional Reconstruction of Heat Transfer in a Flat Flame Furnace through Computer-Based Tomography and Tunable-Diode-Laser Absorption Spectroscopy

“…Then, the values that have been obtained are re-corrected according to the iterative equation of CT algebra to obtain the accurate grid values. The fifth is to calculate the equation and bring it into the next projection according to the corrected and calculated gray value [16]. Afterward, the same operation steps are performed according to the fourth step, and the last projection equation is continued to complete the entire iteration process.…”

Dynamic modelling of grid‐connected permanent magnet synchronous generator wind turbine: rectifier dynamics and control design

“…To develop the dynamic model of the PMSG and the rectifier, two‐phase dq frame of reference is used, in which q ‐axis leads d ‐axis by 90° [6]. The stator voltages of PMSG can be defined in the dq ‐domain using the following equations considering the currents to be flowing out of the generator [8]…”

“…PMSG mechanism is comparatively simple and it does not require any separate electrical excitation [3, 5]. In addition, their performance is highly reliable with minimum maintenance required; therefore, these generators are widely used in low speed, high power wind turbines [6].…”