The high-speed switching of power devices such as MOSFETs and IGBT switches in power conversion systems will generate high amplitude and broadband electromagnetic interference (EMI), which is the most common and unavoidable EMI for electric vehicles. At the same time, interconnecting cables are the carrier of signals and energy transmitted by electrical devices, the antenna effect of cables is the main pathway for EMI radiation propagation, and is one of the main sources of system electromagnetic compatibility (EMC) problems. To analyze the electromagnetic coupling between the high-voltage power conversion system and the low-voltage control system, this paper takes the pulse width modulation (PWM ) wave generated by the IGBT as the EMI source, and uses the actual cable as the analysis object to construct a high and low voltage harness crosstalk model. The simulation analysis analyzes the near-end crosstalk voltage of multiple types of low voltage cable under different conditions of cable spacing and ground distance, obtains the anti-interference performance of low-voltage cables, thus provides guidance for the wiring of the system cable harness.