Abstract: The electromagnetic radiation generated by high-power components such as electric motors in new energy vehicles has a significant impact on the electromagnetic environment in the space around the vehicles. Due to the multi-scale structure of vehicles, traditional full-wave numerical algorithms are time-consuming and inefficient when used to calculate the radiation fields of the vehicles. An equivalent source modeling method for vehicle radiation emission, consisting of transmission line equation theory, method of moments, and dynamic differential evolution (DDE) algorithm, is developed to address the rapid calculation difficulties of large-area radiation fields of the vehicle. First, the transmission line equation and the charge conservation law are integrated to construct the conductive emission model for the high-voltage cable of the motor, and the current responses along the cable are solved by using the high-order FDTD(2, 4) method. Then, the currents along the high-voltage cable are set as excitation sources, and the method of moments is employed to simulate the near radiation field distribution around the vehicle. Finally, the magnetic fields on the scanning plane located at the near region of the vehicle are extracted, and the entire vehicle is represented by a magnetic dipole array. Then the DDE algorithm is applied to train the relationship between the magnitudes and phases of magnetic moments of dipole array and the scanning plane′s magnetic fields to obtain the optimal dipole array, further to predict the far radiation fields of the vehicle rapidly. The results, based on predictions of radiation magnetic fields at various distances and frequency harmonics, show that the root mean square error between the predicted and actual magnetic fields is below 15%, and the prediction time is only in seconds.