The embodiments provide a backplane and a power conversion method and apparatus. The power conversion apparatus includes a first power module, a second power module, and a controller. Each power module includes a signal processor and a corresponding power converter. The signal processor in the first power module sends a generated first carrier signal to the signal processor in the second power module. The signal processor in the second power module determines a second carrier signal by using a period of the first carrier signal, to drive the power converter in the first power module by using the first carrier signal, and drive the power converter in the second power module by using the second carrier signal. This improves operating efficiency of a device in a power conversion process and reduces a power loss.