A power supply circuit includes a first input end (IN1), a second input end (IN2), a first output end (OUT1), and a second output end (OUT2). An input end of a first voltage conversion circuit (VCC) is used as IN1 and connected to an output end of a solar panel. A first output end of the first VCC is used as OUT1 and connected to a first power supply end of a monitoring chip. A second output end of the first VCC is connected to an input end of an energy storage module. An input end of the rectifier circuit is used as IN2 and connected to an AC power network. An output end of the rectifier circuit is connected to an input end of a second VCC. An output end of the second VCC and an output end of the energy storage module are used as OUT2 and connected to a second power supply end of the monitoring chip.