A power supply bus circuit includes a high-voltage power supply circuit, the high-voltage power supply circuit includes at least two first alternating current/direct current converters and further includes at least two high-voltage direct current power supply buses, and the first alternating current/direct current converter connects to mains, adjusts the connected mains into a high-voltage direct current, and outputs the high-voltage direct current to the high-voltage direct current power supply bus that is electrically connected to the first alternating current/direct current converter, where the high-voltage power supply circuit further includes at least one first direct current/direct current converter, where the first direct current/direct current converter performs voltage conversion on the high-voltage direct current between two high-voltage direct current power supply buses connected to the first direct current/direct current converter.