Harmonic current in power grid will cause extra power consumption of electrical equipment and affect the stable operation of power grid. Based on the dynamic model experiment system of 10kV distribution network, a working platform for parallel operation of charging pile was built, which studied the harmonic current components and analyzed the simulation waveform. The results show that with the increase of number of charging piles, the content of harmonic current will decrease correspondingly, the main components are low frequency odd harmonics; When 16 charging piles are connected in parallel, three harmonics are the main components; the waveform of the simulation calculation curve and the actual measurement curve are basically consistent, and the current amplitude of each frequency harmonic wave is basically the same , so it is proved that the dynamic model test platform is reasonable and feasible to test grid’s harmonic current. The dynamic model can provide technical support for harmonic suppression research.