Prediction Method of High Frequency Electromagnetic Noise of Micro Electric Vehicle based on Wavelet Time-Frequency Analysis

In order to reduce the high-frequency electromagnetic noise of micro-electric vehicles, a method for predicting high-frequency electromagnetic noise of micro-electric vehicles based on wavelet time-frequency analysis is proposed. Through the electromagnetic structure design and excitation source, the motor vibration and noise are analyzed to obtain the high-frequency electromagnetic noise harmonics of electric vehicles. The time-step finite element method is used to calculate the electromagnetic force wave of the induction motor used for driving the electric vehicle, and the electromagnetic noise information is collected. Randomly sort the collected power supply margins of electric vehicles connected to charging, correct the corresponding data feature values, establish accurate motor CAD models and FEA models, and complete the prediction of high-frequency electromagnetic noise of micro-electric vehicles. By optimizing the shape of the permanent magnet and the stator potting and sealing, the improved motor was tested and verified, the noise results before and after optimization were compared, and the effectiveness of the motor noise reduction design was proved.