Patent ID: 8106645

Claim:
A power saving system for a household electric appliance comprising: a signal processing unit; a step down network having an adjustable impedance for stepping down an input voltage; and an impedance control switch electrically connected with the step down network and configured for controlling the impedance of the step down network; wherein: the signal processing unit is electrically connected to impedance control switch and configured to monitor the working condition of the household electric appliance, calculate the current demanded by the household electric appliance at a next moment, and transmit a signal to the impedance control switch so as to control the impedance control switch to adjust the impedance of the step down network according to the calculation; the step down network comprises a voltage step down circuit and a conversion impedance control circuit, the voltage step down circuit being connected with the conversion impedance control circuit in parallel through the impedance control switch, the voltage step down circuit comprises a first resistor, a second resistor and a first capacitor, the first resistor being connected with the first capacitor in parallel and connected with the second resistor in series.