Heat pump system, control method thereof and air conditioner

The invention discloses a heat pump system, a control method thereof and an air conditioner, and relates to the technical field of air conditioning. The heat pump system comprises a cold supply assembly, a heat supply assembly, a compressor, a first heat exchanger, a second heat exchanger, a switching type heat exchanger, a first valve and a second valve. The compressor, the first heat exchanger and the second heat exchanger are connected end to end, the first heat exchanger is connected with the cold supply assembly, the second heat exchanger is connected with the heat supply assembly, and one end of the switching type heat exchanger is connected with one end of the first heat exchanger and one end of the second heat exchanger through first valves. The other end of the switching type heat exchanger is connected with the other ends of the first heat exchanger and the second heat exchanger through a second valve. Compared with the prior art, due to the fact that the switching type heat exchanger connected betw