Air source heat pump system capable of cascade heating in winter

Abstract

The invention discloses an air source heat pump system capable of realizing cascade cycle heating in winter, and aims to provide a heat pump system capable of reducing the initial investment of the system and having high efficiency. The exhaust end of the first compressor is connected to the first port of the four-way reversing valve, the third port of the four-way reversing valve is connected to the suction end of the first compressor, and the second port of the four-way reversing valve is The heater and the first throttling valve are connected to the first port of the first indoor heat exchanger and the first port of the low-temperature side of the condensing evaporator, and the second port of the first indoor heat exchanger is connected to the fourth port of the four-way reversing valve. There is a first valve between the ports, a second valve between the second port on the low temperature side of the condensing evaporator and the fourth port of the four-way reversing valve; the suction end of the second compressor and the second port on the high temperature side of the condensing evaporator The exhaust end of the second compressor is connected to the first interface on the high temperature side of the condensing evaporator through the second indoor heat exchanger and the second throttle valve. The system has simple structure and high stability.

Description

technical field [0001] The invention relates to the technical field of refrigeration, and more specifically relates to an air source heat pump system capable of realizing cascade cycle heating in winter. Background technique [0002] In order to improve the thermal efficiency of the heat pump system, a two-stage compression cycle system is generally used for heating in winter, and heating can be achieved at a lower temperature. [0003] However, the air source heat pump technology for winter heating with a two-stage compression system has the following defects in its application: [0004] If the equipment is selected according to the heating load that meets the outdoor temperature of -25°C, the cooling capacity of the unit during cooling in summer is far greater than the cooling load of the building, and more than half of the units will be idle during operation, resulting in a large initial investment of the system, resulting in waste. On the other hand, the air source heat...

AI Technical Summary

Problems solved by technology

However, since the cryogenic working medium is in a supercritical state at room temperature, an expansion vessel is usually installed at the cryogenic stage, and the system is complicated

Moreover, the selection of traditional cascade air source heat pump systems is based on winter load requirements. During summer operation, the cooling capacity provided by the system is too large, resulting in waste of resources. It is not suitable for heating in winter and supply in summer. Cold air source heat pump system

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