The invention discloses an engine-driven
cascade heat pump device which is characterized by comprising a
cascade heat pump system, at least an engine
system and a water loop, wherein the
cascade heat pump system comprises a high-temperature circulating system and a low-temperature circulating system; a high-temperature compressor, a condenser, a high-temperature reservoir, a high-temperature throttling valve, a high-temperature
refrigerant heater, a condensation
evaporator, a high-temperature air-liquid separator and a
refrigerant side valve form a high-temperature
refrigerant circulating system; a low-temperature compressor, a condensation
evaporator, a low-temperature reservoir, a low-temperature throttling valve, a low-temperature refrigerant heater, an
evaporator, a low-temperature air-liquid separator and a refrigerant side valve form a low-temperature refrigerant circulating system; and the engine system comprises an engine, an engine cooling
heat exchanger, a
smoke heat exchanger, a cooling water
bypass valve and a fuel regulating valve. The engine-driven cascade heat pump device disclosed by the invention can improve the utilization efficiency of fuel, realize high-efficiency utilization of energy sources, reducing
pollution, and realizing multiple functions of refrigerating in summer, heating in winter, preparing domestic hot water and the like with the same unit.