A power device includes a power factor corrector, an auxiliary capacitor, a switching device, an auxiliary boost circuit, a controller and a voltage conversion device. The switching device has a first end electrically connected to the output end of the power factor corrector, and a second end electrically connected to one end of the auxiliary capacitor. An output end of the auxiliary boost circuit is electrically connected to the output end of the power factor corrector, an input end of the auxiliary boost circuit is electrically connected to a middle end of the switching device, and a ground end of the auxiliary boost circuit is electrically connected to another end of the auxiliary capacitor. The controller is electrically connected to the switching device and the auxiliary boost circuit. The input end of the voltage conversion device is electrically connected to the output end of the power factor corrector.