Heat pump system without fluctuation of defrosting water temperature

A heat pump system without fluctuation of defrosting water temperature is characterized by comprising a compressor, a four-way valve, a gas-liquid separator, a first electromagnetic valve, a plate heat exchanger, a liquid storage tank, a second electromagnetic valve, a first heat exchanger, a second heat exchanger, an electronic expansion valve, a third electromagnetic valve, a fourth electromagnetic valve, a fifth electromagnetic valve, a sixth electromagnetic valve, a seventh electromagnetic valve, an eighth electromagnetic valve and a one-way valve. The defrosting heat exchange conversion pipeline is communicated with the first heat exchanger and the second heat exchanger; the other end of the defrosting loop is communicated with a seventh electromagnetic valve end and an eighth electromagnetic valve end of the defrosting conversion and heating pipeline, and the first branch and the second support are communicated with the first heat exchanger and the second heat exchanger respectively; during defrosting,