Lightning is a serious threat to the safe operation of wind turbines. Based on the lightning engineering model and the dipole radiation theory

we established a calculation model of the electromagnetic field

and simulated the return strike to wind turbine and the waveform of the electromagnetic field.Compared with lightning strikes to the ground

the results show that there is an obvious initial peak

followed by a quick decrease

and the waveform is oscillatory. At present

the lightning location system can not be adopted to correctly identify such waveforms

leading to overestimation the apex of the return strike current. A vertical electric field at 50 km is taken as an example

and the lightning current inversed by the lightning location system will be expected to be over three times greater than true value. The electric field components

including electrostatic component

induction component and radiation component

at different distances are calculated

indicating the reason for the electric field enhancement is the enhancement of the radiation component. The detailed analyses show that the enhancement effect is insensitive to the engineering model

indicating that the radiation enhancement is mainly contributed by the wind turbine; the electromagnetic field enhancement factor increases gradually with the increase of the distance between observation point and lightning channel

and tends to be saturated. As the height of wind turbines generally changes from 100 m to 200 m

the enhancement may reach 3 times. The research conclusions have reference value for improving the cloud-to-ground lightning monitoring efficiency and lightning current inversion accuracy in wind farms.