CN111964261A

CN111964261A - Concentration-adjustable wide-temperature-area directly-heated heat pump water heater and working method thereof

Info

Publication number: CN111964261A
Application number: CN202010883571.XA
Authority: CN
Inventors: 巨福军; 范晓伟; 郑慧凡; 李志强; 王方; 宋昊展; 周晓磊; 任鹏翔; 单一森
Original assignee: Zhongyuan University of Technology
Current assignee: Zhongyuan University of Technology
Priority date: 2020-08-28
Filing date: 2020-08-28
Publication date: 2020-11-20

Abstract

The invention provides a concentration-adjustable wide-temperature-zone directly-heated heat pump water heater and a working method thereof, wherein the concentration-adjustable wide-temperature-zone directly-heated heat pump water heater comprises a main circulation loop, an air supplementing branch and a concentration adjusting branch, wherein the main circulation loop is provided with a compressor, a condenser, a high-pressure liquid storage device, a subcooler, an economizer, a first expansion valve and an evaporator which are sequentially connected; the air supply branch is provided with a second expansion valve, an economizer and a stop valve which are connected in sequence; the concentration regulating branch is formed by connecting a working medium supplement expansion valve, a component separation and working medium storage tank, an air supplement concentration regulating valve and a liquid supplement concentration regulating valve. The invention comprehensively applies the technology of enhanced vapor injection and working medium concentration regulation, can simultaneously realize the remarkable improvement of the low-temperature performance of the heat pump water heater, the remarkable expansion of the applicable temperature zone and the remarkable improvement of the comprehensive energy efficiency all the year round, and has the advantages of simple rectification structure, high component separation efficiency, simple control, safety and reliability.

Description

Concentration-adjustable wide-temperature-area directly-heated heat pump water heater and working method thereof

Technical Field

The invention relates to the technical field of heat pump water heaters, in particular to a concentration-adjustable wide-temperature-zone directly-heated heat pump water heater and a working method thereof.

Background

The operation energy consumption of buildings in China accounts for about 20% of the total social energy consumption, wherein the domestic hot water energy consumption is the fourth great contributor after the heat supply energy consumption, the air conditioner energy consumption and the illumination energy consumption. With the development of economy and the improvement of living standard, the demand of domestic hot water will continue to increase rapidly. Therefore, reducing the energy consumption of domestic hot water is an important way for achieving the purposes of energy conservation and emission reduction.

Compared with the traditional water heaters (gas water heaters, electric water heaters and solar water heaters), the heat pump water heater has the advantages of high efficiency, environmental protection, safety, reliability and the like, and has remarkable energy-saving and emission-reducing effects, so that the heat pump water heater is greatly recommended and supported by governments of various countries. As a heat pump water heater which is most widely popularized and applied at present, although an air source heat pump water heater can obtain a good application effect in southern areas with high outdoor environment temperature in winter, the air source heat pump water heater is difficult to popularize and apply in large scale in northern areas with low outdoor environment temperature in winter, and the main reason is that the air source heat pump water heater has the problems of serious attenuation of heating capacity and system energy efficiency, overlarge pressure ratio, overhigh exhaust temperature and the like in a low-temperature environment. Therefore, how to improve the low-temperature heating performance of the system is a difficult problem to be solved urgently in order to realize large-scale popularization and application of the air source heat pump water heater in northern areas.

Disclosure of Invention

Aiming at the technical problems in the background technology, the invention provides a concentration-adjustable wide-temperature-zone directly-heated heat pump water heater and a working method thereof, and the heat pump water heater can simultaneously realize the remarkable improvement of the low-temperature performance, the remarkable expansion of an applicable temperature zone and the remarkable improvement of the comprehensive energy efficiency all year round through the comprehensive application of the technology of increasing vapor injection and working medium concentration adjustment.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a concentration-adjustable wide-temperature-zone directly-heated heat pump water heater comprises a main circulation loop, an air supply branch and a concentration adjusting branch; the main circulation loop comprises a compressor, an exhaust port of the compressor is communicated with an inlet of a condenser, an outlet of the condenser is communicated with an inlet of a high-pressure liquid storage device, an outlet of the high-pressure liquid storage device is respectively communicated with an inlet of a subcooler and an inlet of a working medium supplementing expansion valve, an outlet of the subcooler is respectively communicated with a first port of the economizer and an inlet of a second expansion valve, a second port of the economizer is communicated with an inlet of the first expansion valve, an outlet of the first expansion valve is respectively communicated with an inlet of an evaporator and an outlet of a liquid supplementing concentration regulating valve, and an outlet of the evaporator is respectively communicated with an air suction port of the compressor and an outlet of the air supplementing;

the air supplementing branch comprises a second expansion valve, an inlet of the second expansion valve is respectively communicated with an outlet of the subcooler and a first port of the economizer, an outlet of the second expansion valve is communicated with a third port of the economizer, a fourth port of the economizer is communicated with an inlet of a stop valve, and an outlet of the stop valve is communicated with an air supplementing port of the compressor;

the concentration adjusting branch comprises a working medium supplementing expansion valve, an inlet of the working medium supplementing expansion valve is respectively communicated with an outlet of the high-pressure liquid storage device and an inlet of the subcooler, an outlet of the working medium supplementing expansion valve is communicated with an inlet of the component separation and working medium storage tank, an exhaust port of the component separation and working medium storage tank is communicated with an inlet of the air supplementing concentration adjusting valve, an outlet of the air supplementing concentration adjusting valve is respectively communicated with an air suction port of the compressor and an outlet of the evaporator, a liquid discharge port of the component separation and working medium storage tank is communicated with an inlet of the liquid supplementing concentration adjusting valve, and an outlet of the liquid supplementing concentration adjusting valve is respectively communicated with an outlet of the first expansion.

Preferably, the middle part and the bottom of the component separation and working medium storage tank are respectively provided with a filler and an electric heater.

Preferably, the compressor is a quasi-two stage compressor.

Preferably, the condenser and the subcooler are shell-and-tube, double-tube or plate heat exchangers, the economizer is a double-tube or plate heat exchanger, and the evaporator is a direct evaporative air cooler.

Preferably, the first expansion valve, the second expansion valve and the working medium supplement expansion valve are electronic expansion valves, thermal expansion valves or manual expansion valves, the stop valves are electromagnetic stop valves or manual stop valves, and the gas supplement concentration regulating valves and the liquid supplement concentration regulating valves are electronic regulating valves or manual regulating valves.

A working method of a concentration-adjustable wide-temperature-zone directly-heated heat pump water heater comprises the following working modes:

s1, normal operation in the normal operation mode: when the suction pressure of the compressor is in the set range, the second expansion valve, the stop valve, the working medium supplement expansion valve, the air supplement concentration regulating valve, the liquid supplement concentration regulating valve and the power supply of the electric heater are kept closed; at the moment, the high-temperature and high-pressure gaseous mixed working medium discharged from the exhaust port of the compressor flows into a condenser, the high-temperature and high-pressure gaseous mixed working medium in the condenser is condensed into a high-temperature and high-pressure liquid mixed working medium, then flows into a subcooler through a high-pressure liquid reservoir, the high-temperature and high-pressure liquid mixed working medium in the subcooler is cooled into a low-temperature and high-pressure liquid mixed working medium, then flows into the economizer through a first port of the economizer, flows out of a second port of the economizer, is throttled into a low-temperature and low-pressure two-phase mixed working medium through a first expansion valve, then flows into an evaporator, absorbs heat in the evaporator, is changed into a low-;

s2, increase in circulating concentration of low-boiling components in the ordinary operation mode: when the suction pressure of the compressor is lower than the lower limit set value, the working medium supplement expansion valve and the air supplement concentration regulating valve are opened, the power supply of the electric heater is turned on, the power of the electric heater and the opening degree of the air supplement concentration regulating valve are regulated to respectively maintain the pressure and the working medium temperature in the component separation tank at corresponding set values, and meanwhile, the second expansion valve, the stop valve and the liquid supplement concentration regulating valve are kept closed; at this moment, the high-temperature and high-pressure gaseous mixed working medium discharged from the exhaust port of the compressor flows into the condenser, and after the high-temperature and high-pressure gaseous mixed working medium in the condenser is condensed into the high-temperature and high-pressure liquid mixed working medium, the high-temperature and high-pressure liquid mixed working medium flows into the high-pressure liquid storage device through the inlet of the high-pressure liquid storage device, and is divided into two paths at the outlet: the high-temperature high-pressure liquid mixed working medium in the concentration regulating branch is throttled into low-pressure two-phase mixed working medium by a working medium supplement expansion valve, then flows into the component separation and working medium storage tank through an inlet of the component separation and working medium storage tank, the gas-state and liquid mixed working medium in the component separation and working medium storage tank is separated, the liquid mixed working medium rich in high-boiling-point components flows downwards along the filler under the action of gravity, and is subjected to heat-mass exchange with the gas-state mixed working medium rich in low-boiling-point components, which is raised by the heating and vaporization of the electric heater, in the filler, so that more low-boiling-point components are vaporized, meanwhile, the liquid mixed working medium rich in high-boiling-point components, which is not vaporized, flows into the component separation and bottom of the working medium storage tank to be stored, and the gas-state mixed working medium rich in low-boiling-point components flows out through an exhaust port of the working, the mixture flows into the compressor through an air suction port of the compressor, so that the circulating concentration of the low boiling point component in the system is increased; the high-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the subcooler, the high-temperature high-pressure liquid mixed working medium in the subcooler is cooled into a low-temperature high-pressure liquid mixed working medium, the low-temperature high-pressure liquid mixed working medium flows into the economizer through a first port of the economizer, flows out of a second port of the economizer, is throttled into a low-temperature low-pressure two-phase mixed working medium through a first expansion valve, flows into the evaporator, absorbs heat in the evaporator to become a low-pressure gas mixed working medium, flows out of the evaporator, is mixed with the gas mixed working medium which is rich in low-boiling-point components and flows out of the gas supplementing concentration regulating;

when the suction pressure of the compressor is increased to the middle set value, the working medium supplement expansion valve, the air supplement concentration regulating valve and the power supply of the electric heater are closed, the system performs conventional operation in a common working mode under the set working medium circulating concentration, and the step S1 is repeated;

s3, increase in circulating concentration of high-boiling components in the normal operation mode: when the suction pressure of the compressor is higher than the upper limit set value, the liquid supplementing concentration regulating valve is opened, the power supply of the electric heater is turned on, the power of the electric heater is regulated to maintain the temperature of the working medium in the component separation tank at the corresponding set value, and meanwhile, the second expansion valve, the stop valve, the working medium supplementing expansion valve and the gas supplementing concentration regulating valve are kept closed; at this time, the high-temperature and high-pressure gaseous mixed working medium discharged from the exhaust port of the compressor flows into the condenser, the gaseous mixed working medium with high temperature and high pressure in the condenser is condensed into liquid mixed working medium with high temperature and high pressure, and then flows into the subcooler through the high-pressure liquid storage device, after the high-temperature high-pressure liquid mixed working medium in the subcooler is cooled into a low-temperature high-pressure liquid mixed working medium, flows into the economizer through a first port of the economizer, flows out of a second port of the economizer, is throttled by a first expansion valve into a low-temperature low-pressure two-phase mixed working medium, and mixed with a liquid mixed working medium rich in high boiling point components which sequentially flows through a liquid discharge port of the component separation and working medium storage tank and a liquid supplementing concentration regulating valve, and then flows into an evaporator, absorbing heat in the evaporator to change into low-pressure gaseous mixed working medium, and then flowing into the compressor through an air suction port of the compressor to increase the circulating concentration of high-boiling-point components in the system;

when the suction pressure of the compressor is reduced to the middle set value, the liquid supplementing concentration regulating valve and the power supply of the electric heater are closed, the system performs conventional operation in a common working mode under the set working medium circulating concentration, and the step S1 is repeated;

s4, normal operation in a low-temperature working mode: when the suction pressure of the compressor is in the set range, the closing of the working medium supplement expansion valve, the air supplement concentration regulating valve, the liquid supplement concentration regulating valve and the power supply of the electric heater is kept; at the moment, the high-temperature high-pressure gaseous mixed working medium discharged from the exhaust port of the compressor flows into the condenser, after the high-temperature high-pressure gaseous mixed working medium in the condenser is condensed into the high-temperature high-pressure liquid mixed working medium, the high-temperature high-pressure gaseous mixed working medium sequentially flows into the subcooler through the inlets of the high-pressure liquid reservoir and the subcooler, and after the high-temperature high-pressure liquid mixed working medium in the subcooler is cooled into the low-temperature high-pressure liquid mixed working medium, the high-temperature: the low-temperature high-pressure liquid mixed working medium in the air supply branch is throttled into a medium-pressure two-phase mixed working medium by a second expansion valve, then flows into the economizer through a third port of the economizer, and flows out of a fourth port of the economizer and flows into a stop valve after the medium-pressure two-phase mixed working medium in the economizer absorbs heat and is changed into a medium-pressure gas mixed working medium, and finally flows into the compressor through an air supply port of the compressor; the low-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the economizer through a first port of the economizer, flows out of a second port of the economizer after being released and cooled again after being throttled into low-temperature low-pressure two-phase mixed working medium through a first expansion valve, flows into the evaporator, absorbs heat in the evaporator to become low-pressure gaseous mixed working medium, and then flows into the compressor through an air suction port of the compressor;

s5, increase of circulating concentration of low-boiling-point components in a low-temperature working mode: when the suction pressure of the compressor is lower than the lower limit set value, the working medium supplement expansion valve and the air supplement concentration regulating valve are opened, the power supply of the electric heater is turned on, the power of the electric heater and the opening degree of the air supplement concentration regulating valve are regulated to respectively maintain the pressure and the working medium temperature in the component separation tank at corresponding set values, and meanwhile, the closing of the liquid supplement concentration regulating valve is kept; at this moment, the high-temperature and high-pressure gaseous mixed working medium discharged from the exhaust port of the compressor flows into the condenser, and after the high-temperature and high-pressure gaseous mixed working medium in the condenser is condensed into the high-temperature and high-pressure liquid mixed working medium, the high-temperature and high-pressure liquid mixed working medium flows into the high-pressure liquid storage device through the inlet of the high-pressure liquid storage device, and is divided into two paths at the outlet: the high-temperature high-pressure liquid mixed working medium in the concentration regulating branch is throttled into low-pressure two-phase mixed working medium by a working medium supplement expansion valve, then flows into the component separation and working medium storage tank through an inlet of the component separation and working medium storage tank, the gas-state and liquid mixed working medium in the component separation and working medium storage tank is separated, the liquid mixed working medium rich in high-boiling-point components flows downwards along the filler under the action of gravity, and is subjected to heat-mass exchange with the gas-state mixed working medium rich in low-boiling-point components, which is raised by the heating and vaporization of the electric heater, in the filler, so that more low-boiling-point components are vaporized, meanwhile, the liquid mixed working medium rich in high-boiling-point components, which is not vaporized, flows into the component separation and bottom of the working medium storage tank to be stored, and the gas-state mixed working medium rich in low-boiling-point components flows out through an exhaust port of the working, the mixture flows into the compressor through an air suction port of the compressor, so that the circulating concentration of the low boiling point component in the system is increased; the high-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the subcooler through the inlet of the cooler, and after the high-temperature high-pressure liquid mixed working medium in the subcooler is cooled into the low-temperature high-pressure liquid mixed working medium, the high-temperature high-pressure liquid mixed working medium is divided into two paths at the outlet of the subcooler: the low-temperature high-pressure liquid mixed working medium in the air supply branch is throttled into a medium-pressure two-phase mixed working medium by a second expansion valve, then flows into the economizer through a third port of the economizer, and flows out of a fourth port of the economizer and flows into a stop valve after the medium-pressure two-phase mixed working medium in the economizer absorbs heat and is changed into a medium-pressure gas mixed working medium, and finally flows into the compressor through an air supply port of the compressor; the low-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the economizer through a first port of the economizer, flows out of a second port of the economizer after being released heat and cooled again, flows into the low-temperature low-pressure two-phase mixed working medium through a first expansion valve, flows into the evaporator, absorbs heat in the evaporator to become low-pressure gaseous mixed working medium, flows out of the evaporator, is mixed with the gaseous mixed working medium which is rich in low-boiling-point components and flows out of the air supplement concentration regulating valve, and flows into the compressor through an air suction port of the compressor;

when the suction pressure of the compressor is increased to the middle set value, the working medium supplement expansion valve, the air supplement concentration regulating valve and the power supply of the electric heater are closed, the system performs conventional operation in a low-temperature working mode under the set working medium circulating concentration, and the step S4 is repeated;

s6, increase of circulating concentration of high-boiling-point components in a low-temperature working mode: when the suction pressure of the compressor is higher than the upper limit set value, the liquid supplementing concentration regulating valve is opened, the power supply of the electric heater is turned on, the power of the electric heater is regulated to maintain the temperature of the working medium in the component separation tank at the corresponding set value, and meanwhile, the working medium supplementing expansion valve and the gas supplementing concentration regulating valve are kept closed; at the moment, the high-temperature high-pressure gaseous mixed working medium discharged from the exhaust port of the compressor flows into the condenser, after the high-temperature high-pressure gaseous mixed working medium in the condenser is condensed into the high-temperature high-pressure liquid mixed working medium, the high-temperature high-pressure gaseous mixed working medium sequentially flows into the subcooler through the inlets of the high-pressure liquid reservoir and the subcooler, and after the high-temperature high-pressure liquid mixed working medium in the subcooler is cooled into the low-temperature high-pressure liquid mixed working medium, the high-temperature: the low-temperature high-pressure liquid mixed working medium in the air supply branch is throttled into a medium-pressure two-phase mixed working medium by a second expansion valve, then flows into the economizer through a third port of the economizer, and flows out of a fourth port of the economizer and flows into a stop valve after the medium-pressure two-phase mixed working medium in the economizer absorbs heat and is changed into a medium-pressure gas mixed working medium, and finally flows into the compressor through an air supply port of the compressor; the low-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the economizer through a first port of the economizer, the low-temperature high-pressure liquid mixed working medium in the economizer releases heat and is cooled again, then the low-temperature high-pressure liquid mixed working medium flows out of a second port of the economizer, is throttled by a first expansion valve into low-temperature low-pressure two-phase mixed working medium, is mixed with the high-boiling-point component-rich liquid mixed working medium which sequentially flows through a liquid discharge port of the component separation and working medium storage tank and the liquid supplementing concentration regulating valve, flows into the evaporator, absorbs heat in the evaporator to become low-pressure gaseous mixed working medium, and then flows into the compressor through an air suction port of the compressor, so that;

and when the suction pressure of the compressor is reduced to the middle set value, closing the liquid supplementing concentration regulating valve and the power supply of the electric heater, performing conventional operation of the system in a low-temperature working mode under the set working medium circulating concentration, and repeating the step S4.

Preferably, the working fluid is a non-azeotropic mixture working fluid.

Compared with the prior art, the invention has the beneficial effects that:

1) by the comprehensive application of the enhanced vapor injection and concentration regulation technologies, the heat pump system has the advantages of two technologies: on one hand, the low-temperature performance (especially heating capacity and heating COP) of the system in a low-temperature working mode can be remarkably improved, an applicable temperature zone can be expanded, on the other hand, the temperature matching condition among heat exchange fluids in a condenser, a subcooler and an evaporator in a common working mode can be improved, and the heating COP of the system is remarkably improved correspondingly under the condition of giving consideration to the heating capacity;

2) according to the invention, the enhanced vapor injection system with the economizer follows a modular independent design principle, under the condition of a certain working medium circulating concentration in the system, the flow of the working medium flowing through the evaporator and the flow of the gas supplementing working medium are independently controlled by the first expansion valve and the second expansion valve respectively, so that the adjustment and the automatic control are easy, and the phenomenon of working medium backflow cannot occur in a gas supplementing branch;

3) the invention adopts the gas-liquid separator with built-in packing (rectifying tower) as a component separation and working medium storage tank, so that the rectifying structure of the heat pump system is obviously simplified, the control of the system is simple, and the automatic control of the system is convenient;

4) the invention carries out component separation under low pressure, thus leading the component separation to have the advantages of high separation speed, high separation efficiency and low energy consumption of the electric heater;

5) the working medium in the main circulation loop does not pass through component separation and a working medium storage tank, and the stability of the working medium circulation concentration in the system is facilitated when the evaporator is defrosted.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic view of the working process of the present invention.

Fig. 2 is a schematic flow chart of the conventional operation in the normal operation mode of the present invention.

FIG. 3 is a schematic flow diagram showing the cyclic concentration rise of the low boiling point component in the normal operation mode of the present invention.

FIG. 4 is a schematic diagram showing the flow of the cyclic concentration increase of the high boiling point component in the normal operation mode of the present invention.

Fig. 5 is a schematic flow chart of the conventional operation in the low-temperature operation mode of the present invention.

FIG. 6 is a schematic flow chart showing the cyclic concentration rise of the low boiling point component in the low temperature operation mode of the present invention.

FIG. 7 is a schematic diagram showing the flow of the cyclic concentration increase of the high boiling point component in the low temperature operation mode of the present invention.

In the figure, 1 is a compressor, 1a is an air suction port of the compressor, 1b is an air discharge port of the compressor, 1c is an air supplement port of the compressor, 2 is a condenser, 2a is an inlet of the condenser, 2b is an outlet of the condenser, 3 is a high pressure reservoir, 3a is an inlet of the high pressure reservoir, 3b is an outlet of the high pressure reservoir, 4 is a subcooler, 4a is an inlet of the subcooler, 4b is an outlet of the subcooler, 5 is an economizer, 5a is a first port, 5b is a second port, 5c is a third port, 5d is a fourth port, 6 is a first expansion valve, 6a is an inlet of the first expansion valve, 6b is an outlet of the first expansion valve, 7 is an evaporator, 7a is an inlet of the evaporator, 7b is an outlet of the evaporator, 8 is a second expansion valve, 8a is an inlet of the second expansion valve, 8b is an outlet of the second expansion valve, and 9 is a stop valve, 9a is an inlet of the stop valve, 9b is an outlet of the stop valve, 10 is a working medium supplement expansion valve, 10a is an inlet of the working medium supplement expansion valve, 10b is an outlet of the working medium compensation expansion valve, 11 is a component separation and working medium storage tank, 11a is an inlet of the component separation and working medium storage tank, 11b is an exhaust port of the component separation and working medium storage tank, 11c is a liquid discharge port of the component separation and working medium storage tank, 11-1 is a filler, 11-2 is an electric heater, 12 is an air supplement concentration regulating valve, 12a is an inlet of the air supplement concentration regulating valve, 12b is an outlet of the air supplement concentration regulating valve, 13 is an air supplement concentration regulating valve, 13a is an inlet of the air supplement concentration regulating valve, and 13b is an outlet of the air supplement.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive effort based on the embodiments of the present invention, are within the scope of the present invention.

Example 1: as shown in fig. 1, a concentration-adjustable wide-temperature-range directly-heated heat pump water heater, in particular to a concentration-adjustable wide-temperature-range directly-heated air source heat pump water heater system, which mainly comprises a main circulation loop, an air supply branch and a concentration adjusting branch; the main circulation loop comprises a compressor 1, an exhaust port 1b of the compressor 1 is communicated with an inlet 2a of a condenser 2, an outlet 2b of the condenser 2 is communicated with an inlet 3a of a high-pressure liquid storage device 3, an outlet 3b of the high-pressure liquid storage device 3 is respectively communicated with an inlet 4a of a subcooler 4 and an inlet 10a of a working medium supplementing expansion valve 10, an outlet 4b of the subcooler 4 is respectively communicated with a first port 5a of an economizer 5 and an inlet 8a of a second expansion valve 8, a second port 5b of the economizer 5 is communicated with an inlet 6a of a first expansion valve 6, an outlet 6b of the first expansion valve 6 is respectively communicated with an inlet 7a of an evaporator 7 and an outlet 13b of a liquid supplementing concentration regulating valve 13, and an outlet 7b of the evaporator 7 is respectively communicated with an air suction port 1a of the compressor 1 and an outlet 12b of a gas supplementing concentration regulating;

the air supplementing branch comprises a second expansion valve 8, an inlet 8a of the second expansion valve 8 is respectively communicated with an outlet 4b of the subcooler 4 and a first port 5a of the economizer 5, an outlet 8b of the second expansion valve 8 is communicated with a third port 5c of the economizer 5, a fourth port 5d of the economizer 5 is communicated with an inlet 9a of a stop valve 9, and an outlet 9b of the stop valve 9 is communicated with an air supplementing port 1c of the compressor 1;

the concentration adjusting branch comprises a working medium supplementing expansion valve 10, an inlet 10a of the working medium supplementing expansion valve 10 is respectively communicated with an outlet 3b of the high-pressure liquid storage device 3 and an inlet 4a of the subcooler 4, an outlet 10b of the working medium supplementing expansion valve 10 is respectively communicated with an inlet 11a of the component separation and working medium storage tank 11, an exhaust port 11b of the component separation and working medium storage tank 11 is communicated with an inlet 12a of the air supplementing concentration adjusting valve 12, an outlet 12b of the air supplementing concentration adjusting valve 12 is respectively communicated with an air suction port 1a of the compressor 1 and an outlet 7b of the evaporator 7, a liquid outlet 11c of the component separation and working medium storage tank 11 is communicated with an inlet 13a of the liquid supplementing concentration adjusting valve 13, and an outlet 13b of the liquid supplementing concentration adjusting valve 13 is respectively communicated with an outlet 6b of the first expansion valve 6 and.

The middle part and the bottom part of the component separation and working medium storage tank 11 are respectively provided with a filler 11-1 and an electric heater 11-2.

The compressor 1 is a quasi-two-stage compressor.

The condenser 2 and the subcooler 4 are shell-and-tube, sleeve-tube or plate heat exchangers, the economizer 5 is a sleeve-tube or plate heat exchanger, and the evaporator 7 is a direct evaporative air cooler.

The working medium used by the system is a non-azeotropic mixed working medium.

The first expansion valve 6, the second expansion valve 8 and the working medium supplement expansion valve 10 are electronic expansion valves, thermal expansion valves or manual expansion valves, the stop valve 9 is an electromagnetic stop valve or a manual stop valve, and the gas supplement concentration regulating valve 12 and the liquid supplement concentration regulating valve 13 are electronic regulating valves or manual regulating valves.

Example 2: the invention relates to a working method of a concentration-adjustable wide-temperature-zone directly-heated heat pump water heater, wherein the control method adopted in the invention can select an air suction pressure control method, a compressor power consumption control valve, a working medium liquid level control method, a superheat degree control valve or a combination thereof, and the following working modes are specifically described by the air suction pressure control method in the embodiment:

the working mode of the heat pump water heater is mainly influenced by the temperature of outdoor air. The heat-pump water heater is operated in a normal operation mode (S1, S2, and S3) when the outdoor air temperature is high, and operated in a low temperature operation mode (S4, S5, and S6) when the outdoor air temperature is low. The application of the enhanced vapor injection technology can obviously improve the heating capacity and COP of the heat pump water heater under the low-temperature working condition and widen the applicable temperature zone of the heat pump water heater. In the working medium concentration regulation and control technology, along with the increase of the circulating concentration of low-boiling-point components, the heating capacity of a system can be increased, the COP of the system is generally reduced (the variation trend of the COP is also related to the temperature matching level of heat exchange fluid in a heat exchanger), and the increase of the heating capacity can further widen the applicable temperature zone of the system.

S1, normal operation in normal operation mode (as shown in fig. 2): when the suction pressure of the compressor 1 is in the set range, the second expansion valve 8, the stop valve 9, the working medium supplementing expansion valve 10, the air supplementing concentration regulating valve 12, the liquid supplementing concentration regulating valve 13 and the electric heater 11-2 are kept closed; at this time, the high-temperature and high-pressure gaseous mixed working medium discharged from the exhaust port 1b of the compressor 1 flows into the condenser 2, the working medium is a non-azeotropic mixed working medium, the high-temperature and high-pressure gaseous mixed working medium in the condenser 2 is condensed into a high-temperature and high-pressure liquid mixed working medium, the high-temperature and high-pressure liquid mixed working medium flows into the subcooler 4 through the high-pressure liquid reservoir 3, the high-temperature and high-pressure liquid mixed working medium in the subcooler 4 is cooled into a low-temperature and high-pressure liquid mixed working medium, the low-temperature and high-pressure liquid mixed working medium flows into the economizer 5 through the first port 5a of the economizer, flows out of the second port 5b of the economizer, is throttled into a low-temperature and low-pressure two-phase mixed working medium through the.

S2, increase in circulating concentration of low boiling point component in normal operation mode (as shown in fig. 3): when the suction pressure of the compressor 1 is lower than the lower limit set value, the heating capacity of the system needs to be increased, and the circulation concentration of the low-boiling-point component can be increased; the working medium supplement expansion valve 10 and the gas supplement concentration regulating valve 12 need to be opened, the power supply of the electric heater 11-2 is opened, the power of the electric heater 11-2 and the opening degree of the gas supplement concentration regulating valve 12 are regulated to respectively maintain the pressure and the working medium temperature in the component separation tank at corresponding set values, and meanwhile, the second expansion valve 8, the stop valve 9 and the liquid supplement concentration regulating valve 13 are kept closed. At this time, the high-temperature and high-pressure gaseous mixed working medium discharged from the exhaust port 1b of the compressor 1 flows into the condenser 2, and after the high-temperature and high-pressure gaseous mixed working medium in the condenser 2 is condensed into the high-temperature and high-pressure liquid mixed working medium, the high-temperature and high-pressure liquid mixed working medium flows into the high-pressure liquid storage device 3 through the inlet 3a of the high-pressure liquid storage device, and is divided into two paths at the outlet 3b of: the high-temperature high-pressure liquid mixed working medium in the concentration adjusting branch is throttled into low-pressure two-phase mixed working medium by the working medium supplement expansion valve 10, then flows into the component separation and working medium storage tank 11 through an inlet 11a of the component separation and working medium storage tank, the gas-phase and liquid mixed working medium in the component separation and working medium storage tank 11 is separated, the liquid mixed working medium rich in high-boiling-point components flows downwards along the packing 11-1 under the action of gravity, and is subjected to heat-mass exchange with the gas-phase mixed working medium rich in low-boiling-point components, which is raised by the heating and vaporization of the electric heater 11-2, in the packing 11-1 to vaporize more low-boiling-point components, meanwhile, the non-vaporized liquid mixed working medium rich in high-boiling-point components flows into the bottom of the component separation and working medium storage tank 11 and is stored, and the gas-phase mixed working medium rich in low-boiling-point components flows out through an exhaust, and mixed with the low-pressure gaseous mixed working medium flowing out of the evaporator 7, and then flows into the compressor 1 through the air suction port 1a of the compressor, so that the circulating concentration of the low-boiling-point component in the system is increased; the high-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the subcooler 4, the high-temperature high-pressure liquid mixed working medium in the subcooler 4 is cooled into a low-temperature high-pressure liquid mixed working medium, the low-temperature high-pressure liquid mixed working medium flows into the economizer 5 through a first port 5a of the economizer, flows out of a second port 5b of the economizer, is throttled into a low-temperature low-pressure two-phase mixed working medium through a first expansion valve 6, flows into the evaporator 7, absorbs heat in the evaporator 7, is changed into a low-pressure gas mixed working medium, flows out, is mixed with the low-boiling-point component-rich gas mixed working medium flowing out through the air supply concentration regulating valve 12, and flows into the compressor.

When the suction pressure of the compressor 1 is increased to the middle set value, the working medium supplement expansion valve 10, the air supplement concentration regulating valve 12 and the power supply of the electric heater 11-2 are closed, the system performs conventional operation under a common working mode under the set working medium circulating concentration, and the step S1 is repeated;

s3, increase in circulating concentration of high boiling point component in normal operation mode (as shown in fig. 4): when the suction pressure of the compressor 1 is higher than the upper limit set value, it means that the heating capacity of the system needs to be reduced, and the circulation concentration of the high boiling point component can be increased; the liquid supplementing concentration regulating valve 13 is required to be opened, the power supply of the electric heater 11-2 is opened, the power of the electric heater 11-2 is regulated to maintain the temperature of the working medium in the component separation tank at a corresponding set value, and meanwhile, the second expansion valve 8, the stop valve 9, the working medium supplementing expansion valve 10 and the gas supplementing concentration regulating valve 12 are kept closed. At this time, the high-temperature high-pressure gaseous mixed working medium discharged from the exhaust port 1b of the compressor 1 flows into the condenser 2, the high-temperature high-pressure gaseous mixed working medium in the condenser 2 is condensed into a high-temperature high-pressure liquid mixed working medium, and then flows into the subcooler 4 through the high-pressure liquid reservoir 3, the high-temperature high-pressure liquid mixed working medium in the subcooler 4 is cooled into a low-temperature high-pressure liquid mixed working medium, and then flows into the economizer 5 through the first port 5a of the economizer, flows out of the second port 5b of the economizer, is throttled into a low-temperature low-pressure two-phase mixed working medium through the first expansion valve 6, and then flows into the evaporator 7 after being mixed with the high-boiling-point component-rich liquid mixed working medium which sequentially flows through the liquid discharge port 11c of the component separation and working medium storage tank and the liquid compensation concentration regulating valve 13, and then flows into the low, the circulating concentration of high boiling point components in the system is increased.

When the suction pressure of the compressor 1 is reduced to the middle set value, the power supply of the liquid supplementing concentration regulating valve 13 and the electric heater 11-2 is closed, the system performs conventional operation in a common working mode under the set working medium circulating concentration, and the step S1 is repeated;

s4, normal operation in low-temperature operation mode (as shown in fig. 5): when the suction pressure of the compressor 1 is in the set range, the power supplies of the working medium supplement expansion valve 10, the gas supplement concentration regulating valve 12, the liquid supplement concentration regulating valve 13 and the electric heater 11-2 are kept closed. At this moment, the high-temperature and high-pressure gaseous mixed working medium discharged from the exhaust port 1b of the compressor 1 flows into the condenser 2, after the high-temperature and high-pressure gaseous mixed working medium in the condenser 2 is condensed into a high-temperature and high-pressure liquid mixed working medium, the high-temperature and high-pressure liquid mixed working medium sequentially flows into the subcooler 4 through the high-pressure liquid reservoir 3 and the inlet 4a of the subcooler, and after the high-temperature and high-pressure liquid mixed working medium in the subcooler 4 is cooled into a low-temperature and high-pressure liquid mixed working medium, the: the low-temperature high-pressure liquid mixed working medium in the air supply branch is throttled into a medium-pressure two-phase mixed working medium by the second expansion valve 8, then flows into the economizer 5 through the third port 5c of the economizer, and flows out of the fourth port 5d of the economizer after the medium-pressure two-phase mixed working medium in the economizer 5 absorbs heat and then is changed into a medium-pressure gas mixed working medium, and flows into the stop valve 9 and finally flows into the compressor 1 through the air supply port 1c of the compressor; the low-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the economizer 5 through a first port 5a of the economizer, flows out of a second port 5b of the economizer after being released heat and cooled again after being throttled into the low-temperature low-pressure two-phase mixed working medium through a first expansion valve 6, flows into the evaporator 7, absorbs heat in the evaporator 7 to become the low-pressure gas mixed working medium, and flows into the compressor 1 through an air suction port 1a of the compressor.

S5, increase of circulating concentration of low boiling point component in low temperature operation mode (as shown in fig. 6): when the suction pressure of the compressor 1 is lower than its lower set value, which means that the heating capacity of the system needs to be increased, it can be achieved by increasing the circulating concentration of the low boiling point component. The working medium supplement expansion valve 10 and the air supplement concentration regulating valve 12 are required to be opened, the power supply of the electric heater 11-2 is opened, the power of the electric heater 11-2 and the opening degree of the air supplement concentration regulating valve 12 are regulated to respectively maintain the pressure and the working medium temperature in the component separation tank at corresponding set values, and meanwhile, the closing of the liquid supplement concentration regulating valve 13 is kept;

at this time, the high-temperature and high-pressure gaseous mixed working medium discharged from the exhaust port 1b of the compressor 1 flows into the condenser 2, and after the high-temperature and high-pressure gaseous mixed working medium in the condenser 2 is condensed into the high-temperature and high-pressure liquid mixed working medium, the high-temperature and high-pressure liquid mixed working medium flows into the high-pressure liquid storage device 3 through the inlet 3a of the high-pressure liquid storage device, and is divided into two paths at the outlet 3b of: the high-temperature high-pressure liquid mixed working medium in the concentration adjusting branch is throttled into low-pressure two-phase mixed working medium by the working medium supplement expansion valve 10, then flows into the component separation and working medium storage tank 11 through an inlet 11a of the component separation and working medium storage tank, the gas-phase and liquid mixed working medium in the component separation and working medium storage tank 11 is separated, the liquid mixed working medium rich in high-boiling-point components flows downwards along the packing 11-1 under the action of gravity, and is subjected to heat-mass exchange with the gas-phase mixed working medium rich in low-boiling-point components, which is raised by the heating and vaporization of the electric heater 11-2, in the packing 11-1 to vaporize more low-boiling-point components, meanwhile, the non-vaporized liquid mixed working medium rich in high-boiling-point components flows into the bottom of the component separation and working medium storage tank 11 and is stored, and the gas-phase mixed working medium rich in low-boiling-point components flows out through an exhaust, and mixed with the low-pressure gaseous mixed working medium flowing out of the evaporator 7, and then flows into the compressor 1 through the air suction port 1a of the compressor, so that the circulating concentration of the low-boiling-point component in the system is increased;

the high-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the subcooler 4 through the inlet 4a of the cooler, and after the high-temperature high-pressure liquid mixed working medium in the subcooler 4 is cooled into the low-temperature high-pressure liquid mixed working medium, the high-temperature high-pressure liquid mixed working medium is divided into two paths at the outlet 4b of the subcooler: the low-temperature high-pressure liquid mixed working medium in the air supply branch is throttled into a medium-pressure two-phase mixed working medium by the second expansion valve 8, then flows into the economizer 5 through the third port 5c of the economizer, and flows out of the fourth port 5d of the economizer after the medium-pressure two-phase mixed working medium in the economizer 5 absorbs heat and then is changed into a medium-pressure gas mixed working medium, and flows into the stop valve 9 and finally flows into the compressor 1 through the air supply port 1c of the compressor; the low-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the economizer 5 through a first port 5a of the economizer, flows out of a second port 5b of the economizer after being released heat and cooled again after being throttled by the first expansion valve 6 into low-temperature low-pressure two-phase mixed working medium, flows into the evaporator 7, absorbs heat in the evaporator 7 to become low-pressure gaseous mixed working medium, flows out after being mixed with the low-boiling-point-component-rich gaseous mixed working medium flowing out through the air-supplementing concentration regulating valve 12, and flows into the compressor 1 through an air inlet 1a of the compressor.

When the suction pressure of the compressor 1 is increased to the middle set value, the working medium supplement expansion valve 10, the air supplement concentration regulating valve 12 and the power supply of the electric heater 11-2 are closed, the system performs the conventional operation under the low-temperature working mode under the set working medium circulating concentration, and the step S4 is repeated.

S6, increase of circulating concentration of high boiling point component in low temperature operation mode (as shown in fig. 7): when the suction pressure of the compressor 1 is higher than the upper limit set value, it means that the heating capacity of the system needs to be reduced, and the circulation concentration of the high boiling point component can be increased; the liquid supplementing concentration regulating valve 13 is required to be opened, the power supply of the electric heater 11-2 is opened, the power of the electric heater 11-2 is regulated to maintain the temperature of the working medium in the component separation tank at a corresponding set value, and meanwhile, the working medium supplementing expansion valve 10 and the gas supplementing concentration regulating valve 12 are kept closed;

at this moment, the high-temperature and high-pressure gaseous mixed working medium discharged from the exhaust port 1b of the compressor 1 flows into the condenser 2, after the high-temperature and high-pressure gaseous mixed working medium in the condenser 2 is condensed into a high-temperature and high-pressure liquid mixed working medium, the high-temperature and high-pressure liquid mixed working medium sequentially flows into the subcooler 4 through the high-pressure liquid reservoir 3 and the inlet 4a of the subcooler, and after the high-temperature and high-pressure liquid mixed working medium in the subcooler 4 is cooled into a low-temperature and high-pressure liquid mixed working medium, the: the low-temperature high-pressure liquid mixed working medium in the air supply branch is throttled into a medium-pressure two-phase mixed working medium by the second expansion valve 8, then flows into the economizer 5 through the third port 5c of the economizer, and flows out of the fourth port 5d of the economizer after the medium-pressure two-phase mixed working medium in the economizer 5 absorbs heat and then is changed into a medium-pressure gas mixed working medium, and flows into the stop valve 9 and finally flows into the compressor 1 through the air supply port 1c of the compressor; the low-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the economizer 5 through a first port 5a of the economizer, the low-temperature high-pressure liquid mixed working medium in the economizer 5 releases heat and is cooled again, then flows out of a second port 5b of the economizer, is throttled by the first expansion valve 6 into low-temperature low-pressure two-phase mixed working medium, is mixed with the high-boiling-point-component-rich liquid mixed working medium which sequentially flows through a liquid discharge port 11c of the component separation and working medium storage tank and a liquid supplementing concentration regulating valve 13, flows into the evaporator 7, absorbs heat in the evaporator 7 to become low-pressure gaseous mixed working medium, and then flows into the compressor 1 through an air suction port 1a of the compressor, so that the circulating concentration of the high-boiling-.

When the suction pressure of the compressor 1 is reduced to the middle set value, the power supply of the liquid supplementing concentration regulating valve 13 and the electric heater 11-2 is closed, the system performs the conventional operation in the low-temperature working mode under the set working medium circulating concentration, and the step S4 is repeated.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A concentration-adjustable wide-temperature-zone directly-heated heat pump water heater is characterized by comprising a main circulation loop, an air supply branch and a concentration adjusting branch; the main circulation loop comprises a compressor (1), an exhaust port (1 b) of the compressor (1) is communicated with an inlet (2 a) of a condenser (2), an outlet (2 b) of the condenser (2) is communicated with an inlet (3 a) of a high-pressure liquid storage device (3), an outlet (3 b) of the high-pressure liquid storage device (3) is respectively communicated with an inlet (4 a) of a subcooler (4) and an inlet (10 a) of a working medium supplementing expansion valve (10), an outlet (4 b) of the subcooler (4) is respectively communicated with a first port (5 a) of an economizer (5) and an inlet (8 a) of a second expansion valve (8), a second port (5 b) of the economizer (5) is communicated with an inlet (6 a) of a first expansion valve (6), an outlet (6 b) of the first expansion valve (6) is respectively communicated with an inlet (7 a) of an evaporator (7) and an outlet (13 b) of a liquid supplementing concentration regulating valve (13), an outlet (7 b) of the evaporator (7) is respectively communicated with an air suction port (1 a) of the compressor (1) and an outlet (12 b) of the air supplement concentration regulating valve (12);

the air supplementing branch comprises a second expansion valve (8), an inlet (8 a) of the second expansion valve (8) is respectively communicated with an outlet (4 b) of the subcooler (4) and a first port (5 a) of the economizer (5), an outlet (8 b) of the second expansion valve (8) is communicated with a third port (5 c) of the economizer (5), a fourth port (5 d) of the economizer (5) is communicated with an inlet (9 a) of the stop valve (9), and an outlet (9 b) of the stop valve (9) is communicated with an air supplementing port (1 c) of the compressor (1);

the concentration adjusting branch comprises a working medium supplementing expansion valve (10), an inlet (10 a) of the working medium supplementing expansion valve (10) is respectively communicated with an outlet (3 b) of the high-pressure liquid storage device (3) and an inlet (4 a) of the subcooler (4), an outlet (10 b) of the working medium supplementing expansion valve (10) is communicated with an inlet (11 a) of the component separation and working medium storage tank (11), an exhaust port (11 b) of the component separation and working medium storage tank (11) is communicated with an inlet (12 a) of the air supplement concentration adjusting valve (12), an outlet (12 b) of the air supplement concentration adjusting valve (12) is respectively communicated with an air suction port (1 a) of the compressor (1) and an outlet (7 b) of the evaporator (7), a liquid discharge port (11 c) of the component separation and working medium storage tank (11) is communicated with an inlet (13 a) of the liquid supplement concentration adjusting valve (13), and an outlet (13 b) of the liquid supplement concentration adjusting valve (13) is respectively communicated with an outlet (6 b) of the first expansion valve (6 The inlets (7 a) of the devices (7) are communicated.

2. The concentration-adjustable wide-temperature-zone directly-heated heat pump water heater according to claim 1, wherein the middle part and the bottom part of the component separation and working medium storage tank (11) are respectively provided with a filler (11-1) and an electric heater (11-2).

3. The concentration-adjustable wide-temperature-zone direct-heating heat pump water heater according to claim 1, wherein the compressor (1) is a quasi-two-stage compressor.

4. The concentration-adjustable wide-temperature-zone direct-heating heat pump water heater according to claim 1, wherein the condenser (2) and the subcooler (4) are shell-tube, sleeve-tube or plate heat exchangers, the economizer (5) is a sleeve-tube or plate heat exchanger, and the evaporator (7) is a direct evaporative air cooler.

5. The concentration-adjustable wide-temperature-zone directly-heated heat pump water heater according to claim 1, wherein the first expansion valve (6), the second expansion valve (8) and the working medium supplement expansion valve (10) are electronic expansion valves, thermostatic expansion valves or manual expansion valves, the stop valve (9) is an electromagnetic stop valve or a manual stop valve, and the gas supplement concentration regulating valve (12) and the liquid supplement concentration regulating valve (13) are electronic regulating valves or manual regulating valves.

6. The working method of the concentration-adjustable wide-temperature-zone directly-heated heat pump water heater according to any one of claims 1 to 5, characterized by comprising the following working modes:

s1, normal operation in the normal operation mode: when the suction pressure of the compressor (1) is in the set range, the closing of the power supplies of the second expansion valve (8), the stop valve (9), the working medium supplement expansion valve (10), the air supplement concentration regulating valve (12), the liquid supplement concentration regulating valve (13) and the electric heater (11-2) is kept; at the moment, high-temperature and high-pressure gaseous mixed working media discharged from an exhaust port (1 b) of the compressor (1) flow into the condenser (2), after being condensed into high-temperature and high-pressure liquid mixed working media in the condenser (2), the high-temperature and high-pressure gaseous mixed working media flow into the subcooler (4) through the high-pressure liquid reservoir (3), after being cooled into low-temperature and high-pressure liquid mixed working media in the subcooler (4), the low-temperature and high-pressure liquid mixed working media flow into the economizer (5) through a first port (5 a) of the economizer, flow out of a second port (5 b) of the economizer, are throttled into low-temperature and low-pressure two-phase mixed working media through a first expansion valve (6), flow into the evaporator (7), absorb heat in the evaporator (7) and become low-pressure gaseous mixed working media, and then flow into the compressor (1) through;

s2, increase in circulating concentration of low-boiling components in the ordinary operation mode: when the suction pressure of the compressor (1) is lower than the lower limit set value, a working medium supplement expansion valve (10) and a gas supplement concentration regulating valve (12) are opened, the power supply of the electric heater (11-2) is turned on, the power of the electric heater (11-2) and the opening degree of the gas supplement concentration regulating valve (12) are regulated to enable the pressure and the working medium temperature in the component separation tank to be respectively maintained at corresponding set values, and meanwhile, the second expansion valve (8), the stop valve (9) and the liquid supplement concentration regulating valve (13) are kept closed; at this moment, the high-temperature and high-pressure gaseous mixed working medium discharged by the exhaust port (1 b) of the compressor (1) flows into the condenser (2), and after the high-temperature and high-pressure gaseous mixed working medium is condensed into the high-temperature and high-pressure liquid mixed working medium in the condenser (2), the high-temperature and high-pressure liquid mixed working medium flows into the high-pressure liquid storage device (3) through the inlet (3 a) of the high-pressure liquid storage device, and is divided into two paths at the outlet (3 b) of: the high-temperature high-pressure liquid mixed working medium in the concentration adjusting branch is throttled into low-pressure two-phase mixed working medium by a working medium supplement expansion valve (10), then flows into the component separation and working medium storage tank (11) through an inlet (11 a) of the component separation and working medium storage tank, the gas-state and liquid mixed working medium in the component separation and working medium storage tank (11) is separated, the liquid mixed working medium rich in high-boiling-point components flows downwards along a filler (11-1) under the action of gravity, and is subjected to heat-mass exchange with the gas-state mixed working medium rich in low-boiling-point components and rising due to heating and vaporization of an electric heater (11-2) in the filler (11-1) to vaporize more low-boiling-point components, meanwhile, the liquid mixed working medium rich in high-boiling-point components and not vaporized flows into the bottom of the component separation and working medium storage tank (11) and the gas-state mixed working medium rich in low-boiling-point components sequentially passes through an exhaust port (11 b The concentration regulating valve (12) flows out, is mixed with the low-pressure gaseous mixed working medium flowing out from the evaporator (7), and then flows into the compressor (1) through the air suction port (1 a) of the compressor, so that the circulating concentration of the low-boiling-point components in the system is increased; the high-temperature high-pressure liquid mixed working medium in the main circulation loop flows into a subcooler (4), the high-temperature high-pressure liquid mixed working medium in the subcooler (4) is cooled into a low-temperature high-pressure liquid mixed working medium, then flows into an economizer (5) through a first port (5 a) of the economizer, flows out of a second port (5 b) of the economizer, is throttled into a low-temperature low-pressure two-phase mixed working medium through a first expansion valve (6), flows into an evaporator (7), absorbs heat in the evaporator (7), then flows out of the low-pressure gas mixed working medium, is mixed with the low-boiling-point-component-rich gas mixed working medium flowing out of an air-supplementing concentration regulating valve (12), and then flows into a compressor (1) through an air inlet (1 a) of the compressor;

when the suction pressure of the compressor (1) is increased to a middle set value, the power supplies of the working medium supplement expansion valve (10), the air supplement concentration regulating valve (12) and the electric heater (11-2) are closed, the system normally operates in a common working mode under the set working medium circulating concentration, and the step S1 is repeated;

s3, increase in circulating concentration of high-boiling components in the normal operation mode: when the suction pressure of the compressor (1) is higher than the upper limit set value, the liquid supplementing concentration regulating valve (13) is opened, the power supply of the electric heater (11-2) is turned on, the power of the electric heater (11-2) is regulated to maintain the temperature of the working medium in the component separation tank at the corresponding set value, and meanwhile, the second expansion valve (8), the stop valve (9), the working medium supplementing expansion valve (10) and the gas supplementing concentration regulating valve (12) are kept closed; at the moment, the high-temperature and high-pressure gaseous mixed working medium discharged by an exhaust port (1 b) of the compressor (1) flows into the condenser (2), the high-temperature and high-pressure gaseous mixed working medium in the condenser (2) is condensed into a high-temperature and high-pressure liquid mixed working medium, then the high-temperature and high-pressure liquid mixed working medium flows into the subcooler (4) through the high-pressure liquid reservoir (3), the high-temperature and high-pressure liquid mixed working medium in the subcooler (4) is cooled into a low-temperature and high-pressure liquid mixed working medium, then the low-temperature and high-pressure liquid mixed working medium flows into the economizer (5) through a first port (5 a) of the economizer, flows out of a second port (5 b) of the economizer, is throttled into a low-temperature and low-pressure two-phase mixed working medium through a first expansion valve (6), and then the low-temperature and high-pressure mixed working medium, absorbing heat in the evaporator (7) to become low-pressure gaseous mixed working medium, and then flowing into the compressor (1) through an air suction port (1 a) of the compressor to increase the circulating concentration of high-boiling-point components in the system;

when the suction pressure of the compressor (1) is reduced to the middle set value, the power supply of the liquid supplementing concentration regulating valve (13) and the electric heater (11-2) is closed, the system normally operates in a common working mode under the set working medium circulating concentration, and the step S1 is repeated;

s4, normal operation in a low-temperature working mode: when the suction pressure of the compressor (1) is in the set range, the closing of the working medium supplement expansion valve (10), the gas supplement concentration regulating valve (12), the liquid supplement concentration regulating valve (13) and the power supply of the electric heater (11-2) is kept; at this moment, the gaseous mixed working medium of the high-temperature high-pressure that is discharged by gas vent (1 b) of compressor (1) flows into condenser (2), behind the gaseous mixed working medium of high-temperature high-pressure in condenser (2) condensed into the liquid mixed working medium of high-temperature high-pressure, flow into subcooler (4) through import (4 a) of high-pressure reservoir (3) and subcooler in proper order, behind the liquid mixed working medium of high-temperature high-pressure in subcooler (4) cooled down to the liquid mixed working medium of low-temperature high-pressure, punishment in export (4 b) of subcooler is two tunnel: the low-temperature high-pressure liquid mixed working medium in the air supply branch is throttled into a medium-pressure two-phase mixed working medium by a second expansion valve (8), then flows into the economizer (5) through a third port (5 c) of the economizer, and flows out of a fourth port (5 d) of the economizer after the medium-pressure two-phase mixed working medium in the economizer (5) absorbs heat and is changed into a medium-pressure gas mixed working medium and then flows into a stop valve (9), and finally flows into the compressor (1) through an air supply port (1 c) of the compressor; the low-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the economizer (5) through a first port (5 a) of the economizer, the low-temperature high-pressure liquid mixed working medium in the economizer (5) releases heat and is cooled again, the low-temperature high-pressure liquid mixed working medium flows out of a second port (5 b) of the economizer, the low-temperature low-pressure liquid mixed working medium is throttled by a first expansion valve (6) and flows into an evaporator (7), the low-temperature low-pressure liquid mixed working medium absorbs heat in the evaporator (7) and is changed into a low-pressure gaseous mixed working medium, and the low-temperature high-pressure liquid mixed working medium;

s5, increase of circulating concentration of low-boiling-point components in a low-temperature working mode: when the suction pressure of the compressor (1) is lower than the lower limit set value, a working medium supplement expansion valve (10) and a gas supplement concentration regulating valve (12) are opened, the power supply of the electric heater (11-2) is turned on, and the power of the electric heater (11-2) and the opening degree of the gas supplement concentration regulating valve (12) are regulated to respectively maintain the pressure and the working medium temperature in the component separation tank at corresponding set values, and meanwhile, the closing of the liquid supplement concentration regulating valve (13) is kept; at this moment, the high-temperature and high-pressure gaseous mixed working medium discharged by the exhaust port (1 b) of the compressor (1) flows into the condenser (2), and after the high-temperature and high-pressure gaseous mixed working medium is condensed into the high-temperature and high-pressure liquid mixed working medium in the condenser (2), the high-temperature and high-pressure liquid mixed working medium flows into the high-pressure liquid storage device (3) through the inlet (3 a) of the high-pressure liquid storage device, and is divided into two paths at the outlet (3 b) of: the high-temperature high-pressure liquid mixed working medium in the concentration adjusting branch is throttled into low-pressure two-phase mixed working medium by a working medium supplement expansion valve (10), then flows into the component separation and working medium storage tank (11) through an inlet (11 a) of the component separation and working medium storage tank, the gas-state and liquid mixed working medium in the component separation and working medium storage tank (11) is separated, the liquid mixed working medium rich in high-boiling-point components flows downwards along a filler (11-1) under the action of gravity, and is subjected to heat-mass exchange with the gas-state mixed working medium rich in low-boiling-point components and rising due to heating and vaporization of an electric heater (11-2) in the filler (11-1) to vaporize more low-boiling-point components, meanwhile, the liquid mixed working medium rich in high-boiling-point components and not vaporized flows into the bottom of the component separation and working medium storage tank (11) and the gas-state mixed working medium rich in low-boiling-point components sequentially passes through an exhaust port (11 b The concentration regulating valve (12) flows out, is mixed with the low-pressure gaseous mixed working medium flowing out from the evaporator (7), and then flows into the compressor (1) through the air suction port (1 a) of the compressor, so that the circulating concentration of the low-boiling-point components in the system is increased; the high-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the subcooler (4) through the inlet (4 a) of the cooler, and after the high-temperature high-pressure liquid mixed working medium in the subcooler (4) is cooled into the low-temperature high-pressure liquid mixed working medium, the high-temperature high-pressure liquid mixed working medium is divided into two paths at the outlet (4 b) of the subcooler: the low-temperature high-pressure liquid mixed working medium in the air supply branch is throttled into a medium-pressure two-phase mixed working medium by a second expansion valve (8), then flows into the economizer (5) through a third port (5 c) of the economizer, and flows out of a fourth port (5 d) of the economizer after the medium-pressure two-phase mixed working medium in the economizer (5) absorbs heat and is changed into a medium-pressure gas mixed working medium and then flows into a stop valve (9), and finally flows into the compressor (1) through an air supply port (1 c) of the compressor; the low-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the economizer (5) through a first port (5 a) of the economizer, the low-temperature high-pressure liquid mixed working medium in the economizer (5) releases heat and is cooled again, the low-temperature high-pressure liquid mixed working medium flows out of a second port (5 b) of the economizer, the low-temperature low-pressure liquid mixed working medium is throttled by a first expansion valve (6) and flows into an evaporator (7), the low-temperature low-pressure liquid mixed working medium is absorbed in the evaporator (7) and flows out after being changed into low-pressure gaseous mixed working medium, the low-temperature low-pressure liquid mixed working medium is mixed with the gaseous mixed working medium which is rich in low-boiling-point components and flows out through an;

when the suction pressure of the compressor (1) is increased to a middle set value, the power supplies of the working medium supplement expansion valve (10), the air supplement concentration regulating valve (12) and the electric heater (11-2) are closed, the system performs conventional operation in a low-temperature working mode under the set working medium circulating concentration, and the step S4 is repeated;

s6, increase of circulating concentration of high-boiling-point components in a low-temperature working mode: when the suction pressure of the compressor (1) is higher than the upper limit set value, a liquid supplementing concentration regulating valve (13) is opened, the power supply of the electric heater (11-2) is turned on, the power of the electric heater (11-2) is regulated to maintain the temperature of the working medium in the component separation tank at the corresponding set value, and meanwhile, the working medium supplementing expansion valve (10) and the air supplementing concentration regulating valve (12) are kept closed; at this moment, the gaseous mixed working medium of the high-temperature high-pressure that is discharged by gas vent (1 b) of compressor (1) flows into condenser (2), behind the gaseous mixed working medium of high-temperature high-pressure in condenser (2) condensed into the liquid mixed working medium of high-temperature high-pressure, flow into subcooler (4) through import (4 a) of high-pressure reservoir (3) and subcooler in proper order, behind the liquid mixed working medium of high-temperature high-pressure in subcooler (4) cooled down to the liquid mixed working medium of low-temperature high-pressure, punishment in export (4 b) of subcooler is two tunnel: the low-temperature high-pressure liquid mixed working medium in the air supply branch is throttled into a medium-pressure two-phase mixed working medium by a second expansion valve (8), then flows into the economizer (5) through a third port (5 c) of the economizer, and flows out of a fourth port (5 d) of the economizer after the medium-pressure two-phase mixed working medium in the economizer (5) absorbs heat and is changed into a medium-pressure gas mixed working medium and then flows into a stop valve (9), and finally flows into the compressor (1) through an air supply port (1 c) of the compressor; the low-temperature high-pressure liquid mixed working medium in the main circulation loop flows into the economizer (5) through a first port (5 a) of the economizer, the low-temperature high-pressure liquid mixed working medium in the economizer (5) releases heat and is cooled again, the low-temperature high-pressure liquid mixed working medium flows out of a second port (5 b) of the economizer, the low-temperature low-pressure liquid mixed working medium is throttled by a first expansion valve (6), the low-temperature low-pressure liquid mixed working medium is mixed with the high-boiling-point-component-rich liquid mixed working medium which sequentially flows through a liquid discharge port (11 c) of a component separation and working medium storage tank and a liquid supplement concentration regulating valve (13), the mixed working medium flows into an evaporator (7), the mixed working medium absorbs heat in the evaporator (7) and is changed into a gas mixed working medium, and the gas mixed working medium;

when the suction pressure of the compressor (1) is reduced to the middle set value, the power supply of the liquid supplementing concentration regulating valve (13) and the electric heater (11-2) is closed, the system is normally operated under the low-temperature working mode under the set working medium circulating concentration, and the step S4 is repeated.

7. The working method of the wide-temperature-zone directly-heated air source heat pump water heater according to claim 6, wherein the working medium is a non-azeotropic mixed working medium.