A power supply bus circuit, includes a voltage regulator circuit, and an impedance isolation circuit, and further including one or more voltage adjustment circuits, where the voltage regulator circuit receives a direct current signal, adjusts a voltage of the direct current signal to a first preset voltage, and outputs a direct current signal of the first preset voltage to the impedance isolation circuit; the impedance isolation circuit receives the direct current signal of the first preset voltage, adjusts the direct current signal of the first preset voltage to an alternating current signal, and outputs, by using a transformer, the alternating current signal in an isolated way and converts the alternating current signal that is output in an isolated way to an isolated direct current signal, and outputs the isolated direct current signal to the voltage adjustment circuit.