A heat pump system, comprising: an outdoor heat exchanger; and an electromagnetic heating assembly, comprising: an induction heating sheet, a heat insulation plate, and an electromagnetic induction wire coil, the induction heating sheet being in contact with the outdoor heat exchanger, the electromagnetic induction wire coil being attached to the heat insulation plate, the heat insulation plate being connected to the outdoor heat exchanger or the induction heating sheet, and the induction heating sheet being coupled with the electromagnetic induction wire coil by communication, a controller configured to carry out a control method for the heat pump system wherein the control method comprises: starting an electromagnetic heating assembly when the heat pump system is in a heating-start mode or a defrosting mode, wherein in a normal heating mode, if T is less than T 0, and a compressor of the heat pump reaches a maximum frequency, the electromagnetic heating assembly is started; and if T is greater than or equal to T 0, and the compressor does not reach the maximum frequency, the electromagnetic heating assembly stops heating, wherein a discharge temperature of the compressor is represented by T, and a target discharge temperature of the heat pump system is represented by T 0. an outdoor heat exchanger; and an electromagnetic heating assembly, comprising: an induction heating sheet, a heat insulation plate, and an electromagnetic induction wire coil, the induction heating sheet being in contact with the outdoor heat exchanger, the electromagnetic induction wire coil being attached to the heat insulation plate, the heat insulation plate being connected to the outdoor heat exchanger or the induction heating sheet, and the induction heating sheet being coupled with the electromagnetic induction wire coil by communication, a controller configured to carry out a control method for the heat pump system wherein the control method comprises: starting an electromagnetic heating assembly when the heat pump system is in a heating-start mode or a defrosting mode, wherein in a normal heating mode, if T is less than T 0, and a compressor of the heat pump reaches a maximum frequency, the electromagnetic heating assembly is started; and if T is greater than or equal to T 0, and the compressor does not reach the maximum frequency, the electromagnetic heating assembly stops heating, wherein a discharge temperature of the compressor is represented by T, and a target discharge temperature of the heat pump system is represented by T 0. an induction heating sheet, a heat insulation plate, and an electromagnetic induction wire coil, the induction heating sheet being in contact with the outdoor heat exchanger, the electromagnetic induction wire coil being attached to the heat insulation plate, the heat insulation plate being connected to the outdoor heat exchanger or the induction heating sheet, and the induction heating sheet being coupled with the electromagnetic induction wire coil by communication, a controller configured to carry out a control method for the heat pump system wherein the control method comprises: starting an electromagnetic heating assembly when the heat pump system is in a heating-start mode or a defrosting mode, wherein in a normal heating mode, if T is less than T 0, and a compressor of the heat pump reaches a maximum frequency, the electromagnetic heating assembly is started; and if T is greater than or equal to T 0, and the compressor does not reach the maximum frequency, the electromagnetic heating assembly stops heating, wherein a discharge temperature of the compressor is represented by T, and a target discharge temperature of the heat pump system is represented by T 0.