A transcritical CO with precooler 2 Heat pump system and water circuit two-way valve control method

Abstract

The invention discloses a transcritical CO based on a precooler 2 The heat pump system and the waterway two-way valve control method, the conventional transcritical CO 2 The heat pump system is assisted by a pre-cooler system; the circulating water circuit is divided into two parts in the system through the three-way water diversion valve and the three-way water collection valve, and connected by the two-way water channel regulating valve and the water channel bypass valve; The ambient temperature sensor, evaporator fin temperature sensor and evaporation pressure sensor are used, and the programmable logic controller is used as the core of acquisition, calculation and control. Through the above system configuration and a well-developed joint control method of temperature, pressure and time, transcritical CO 2 The promotion of heat pump systems to the heating field can make up for the impact of high return water temperature on transcritical CO 2 System performance degradation, proper control of units entering and exiting defrost, and addressing transcritical CO 2 The heat pump system stops heating during a relatively long defrosting time, and the average temperature of the circulating water system drops rapidly.

Description

Technical field [0001] The invention belongs to the technical field of heating, ventilation, refrigeration and heat pumps, and relates to a transcritical CO 2 Heat pump system. Background technique [0002] In recent years, with the rapid development of the national economy, a large number of unhealthy energy supply methods and incomplete environmentally friendly technology development have caused increasingly serious environmental problems and energy crises. This is the current economic development prospects and negative aspects of China. Effect carrying capacity is the most serious problem faced by the eternal contradiction. As the basic direction of national economic development in the past ten years has gradually changed from industry to tertiary industry and supporting industries for residents’ living conditions, energy output fields under the background of industry, commerce and civilian use have also undergone a subtle change. According to reports, the energy consumption ...

AI Technical Summary

Problems solved by technology

[0005] In summary, existing transcritical CO 2 The heat pump system faces three main technical problems in the practical application of the heating field: high-temperature return water directly enters the CO 2 The gas cooler will reduce the system efficiency, the entry and exit judgment conditions and control logic of defrosting should be more accurate and rigorous, and the temperature fluctuation of the circulating water system should be avoided as far as possible during the long-term defrosting process

Images