CN113959130B

CN113959130B - Method and device for controlling water chilling unit and water chilling unit

Info

Publication number: CN113959130B
Application number: CN202111173068.6A
Authority: CN
Inventors: 王书森; 邓善营; 张捷; 毛守博; 顾超
Original assignee: Qingdao Haier Air Conditioner Gen Corp Ltd; Qingdao Haier Air Conditioning Electric Co Ltd; Haier Smart Home Co Ltd
Current assignee: Qingdao Haier Air Conditioner Gen Corp Ltd; Qingdao Haier Air Conditioning Electric Co Ltd; Haier Smart Home Co Ltd
Priority date: 2021-10-08
Filing date: 2021-10-08
Publication date: 2023-06-16
Anticipated expiration: 2041-10-08
Also published as: CN113959130A

Abstract

The application relates to the technical field of refrigeration and discloses a method for controlling a water chilling unit. The water chilling unit comprises a compressor, a condenser and an evaporator; the condenser exchanges heat through a cooling water pipe, and the evaporator exchanges heat through a chilled water pipe; the cooling water pipe comprises a main cooling water inlet pipeline and an auxiliary cooling water inlet pipeline which are connected in parallel, and the auxiliary cooling water inlet pipeline is provided with a second regulating valve; the freezing water pipe comprises a main freezing water inlet pipeline and an auxiliary freezing water inlet pipeline which are connected in parallel, and the auxiliary freezing water inlet pipeline is provided with a fourth regulating valve; the auxiliary cooling water inlet pipeline is contacted or connected with the auxiliary freezing water inlet pipeline; the method comprises the following steps: acquiring operation parameters of a water chilling unit; and under the condition that the running parameters of the water chilling unit meet the set conditions, controlling the second regulating valve and the fourth regulating valve to be opened so as to regulate the water temperatures of the cooling water pipe and the freezing water pipe. The application also discloses a device for controlling the water chilling unit and the water chilling unit.

Description

Method and device for controlling water chilling unit and water chilling unit

Technical Field

The present application relates to the field of refrigeration technologies, for example, to a method and an apparatus for controlling a water chiller, and a water chiller.

Background

Currently, for a chiller, the ratio of the pressure of the condenser to the pressure of the evaporator is referred to as the chiller pressure ratio. When the pressure ratio of the water chilling unit is high, the unloading capacity of the unit is poor, and the compressor is easy to surge. The high pressure ratio can cause the compressor to generate overcurrent, high pressure ratio, high exhaust pressure, low suction pressure faults and the like, and the using range of the unit is affected.

The prior art discloses an anti-surge system of a centrifugal refrigerating unit, wherein a compressor and a throttling device are respectively connected between a condenser and an evaporator, and a boosting branch for reducing the pressure difference between the condenser and the evaporator is arranged between the throttling device and a freezing water inlet; the pressure boosting branch comprises a heat exchange device, the heat exchange device is provided with a refrigerant passage and a water passage, the refrigerant passage is communicated with the condenser and the throttling device, the water passage is communicated with the freezing water inlet and the evaporator, and water entering from the freezing water inlet in the heat exchange device exchanges heat with refrigerant exiting from the condenser.

In the process of implementing the embodiments of the present disclosure, it is found that at least the following problems exist in the related art:

the scheme in the prior art can only adjust the temperature of the freezing water and can not adjust the temperature of the cooling water, so that the effect of reducing the pressure ratio is limited, and the surge can not be well prevented.

Disclosure of Invention

The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosed embodiments. This summary is not an extensive overview, and is intended to neither identify key/critical elements nor delineate the scope of such embodiments, but is intended as a prelude to the more detailed description that follows.

The embodiment of the disclosure provides a method and a device for controlling a water chilling unit and the water chilling unit, so as to improve the effect of reducing the pressure ratio and further prevent surging.

The embodiment of the disclosure provides a method for controlling a water chilling unit, wherein the water chilling unit comprises a compressor, a condenser and an evaporator; the condenser exchanges heat through the cooling water pipe, and the evaporator exchanges heat through the chilled water pipe; the cooling water pipe comprises a main cooling water inlet pipeline and an auxiliary cooling water inlet pipeline which are connected in parallel, and the auxiliary cooling water inlet pipeline is provided with a second regulating valve; the freezing water pipe comprises a main freezing water inlet pipeline and an auxiliary freezing water inlet pipeline which are connected in parallel, and the auxiliary freezing water inlet pipeline is provided with a fourth regulating valve; the auxiliary cooling water inlet pipeline is contacted or connected with the auxiliary freezing water inlet pipeline; the method comprises the following steps: acquiring operation parameters of the water chilling unit; when the running parameters of the water chilling unit meet the set conditions, the second regulating valve and the fourth regulating valve are controlled to be opened, so that cooling water in the auxiliary cooling water inlet pipeline and chilled water in the auxiliary chilled water inlet pipeline exchange heat, and the water temperatures of the cooling water pipe and the chilled water pipe are regulated; wherein the initial states of the second regulating valve and the fourth regulating valve are disconnected.

An embodiment of the present disclosure provides an apparatus for controlling a water chiller, the apparatus including: a processor and a memory storing program instructions, the processor being configured to perform the aforementioned method for controlling a chiller as the program instructions are run.

The embodiment of the disclosure also provides a water chilling unit, which comprises a compressor, a condenser, a throttling device and a condenser which are connected in sequence; the condenser exchanges heat through the cooling water pipe, and the evaporator exchanges heat through the chilled water pipe; the cooling water pipe comprises a main cooling water inlet pipeline and an auxiliary cooling water inlet pipeline which are connected in parallel, and the auxiliary cooling water inlet pipeline is provided with a second regulating valve; the freezing water pipe comprises a main freezing water inlet pipeline and an auxiliary freezing water inlet pipeline which are connected in parallel, and the auxiliary freezing water inlet pipeline is provided with a fourth regulating valve; the auxiliary cooling water inlet pipeline is in contact with or is connected with the auxiliary freezing water inlet pipeline, and under the condition that the second regulating valve and the fourth regulating valve are opened, cooling water in the auxiliary cooling water inlet pipeline exchanges heat with freezing water in the auxiliary freezing water inlet pipeline so as to regulate the water temperatures of the cooling water pipe and the freezing water pipe.

The embodiment of the disclosure provides a method and a device for controlling a water chilling unit and the water chilling unit. The following technical effects can be achieved:

and according to the operation parameters of the water chilling unit, and under the condition that the operation parameters of the water chilling unit meet the set conditions, controlling the second regulating valve and the fourth regulating valve to be opened so as to enable cooling water in the auxiliary cooling water inlet pipeline and chilled water in the auxiliary freezing water inlet pipeline to exchange heat, thereby regulating the water temperatures of the cooling water pipe and the chilled water pipe. The pressure of the condenser and the pressure of the evaporator can be simultaneously regulated by regulating the water temperature of the cooling water pipe and the water temperature of the freezing water pipe, so that the pressure ratio of the water chilling unit can be regulated, the effect of reducing the pressure ratio is improved, and further, the surge is better prevented.

The foregoing general description and the following description are exemplary and explanatory only and are not restrictive of the application.

Drawings

One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements, and in which like reference numerals refer to similar elements, and in which:

fig. 1 is a schematic structural diagram of a water chiller provided in an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of a method for controlling a chiller according to an embodiment of the present disclosure;

FIG. 3 is a schematic illustration of a method for controlling a chiller according to an embodiment of the present disclosure, where r > r ₁ A schematic diagram of controlling the second regulating valve and the fourth regulating valve to be opened;

FIG. 4 is a schematic illustration of another method for controlling a chiller provided by an embodiment of the present disclosure;

FIG. 5 is a schematic illustration of another method for controlling a chiller provided by an embodiment of the present disclosure;

FIG. 6 is a schematic illustration of a method for controlling a chiller according to an embodiment of the present disclosure, at r<r ₃ A schematic diagram of the opening of the second regulating valve and/or the fourth regulating valve;

FIG. 7 is a schematic illustration of another method for controlling a chiller provided by an embodiment of the present disclosure;

FIG. 8 is a schematic diagram of a method for controlling a chiller according to an embodiment of the present disclosure, in which when the temperature of chilled water is less than the temperature of cooling water, the unloading capacity of the chiller is minimized, the temperature of chilled water is less than a target temperature, the difference between the temperature of chilled water and the target temperature is less than a shutdown temperature difference, and the load of a compressor is less than a target load, both the second and fourth control valves are controlled to be opened;

FIG. 9 is a schematic diagram of another method for controlling a chiller provided by an embodiment of the present disclosure;

FIG. 10 is a schematic illustration of another method for controlling a chiller provided by an embodiment of the present disclosure;

FIG. 11 is a schematic illustration of another method for controlling a chiller provided by an embodiment of the present disclosure;

fig. 12 is a schematic diagram of a method for controlling a water chiller according to an embodiment of the present disclosure, in which when the temperature of cooling water is less than the temperature of chilled water and the temperature of cooling water is less than a temperature threshold when the water chiller is started, the second regulating valve and the fourth regulating valve are both controlled to be opened, and the first regulating valve and the third regulating valve are both controlled to be opened;

FIG. 13 is a schematic illustration of another method for controlling a chiller provided by an embodiment of the present disclosure;

FIG. 14 is a schematic diagram of an apparatus for controlling a chiller according to an embodiment of the present disclosure;

fig. 15 is a schematic view of another apparatus for controlling a chiller according to an embodiment of the present disclosure.

Reference numerals:

10. a condenser; 101. a main cooling water inlet pipeline; 1011. a first regulating valve; 102. auxiliary cooling water inlet pipeline; 1021. a second regulating valve; 103. a cooling water outlet pipeline; 20. an evaporator; 201. a main freezing water inlet pipeline; 2011. a third regulating valve; 202. an auxiliary freezing water inlet pipeline; 2021. a fourth regulating valve; 203. freezing a water outlet pipeline; 30. a compressor; 40. a throttle device; 50. a heat exchanger; 60. a one-way valve.

Detailed Description

So that the manner in which the features and techniques of the disclosed embodiments can be understood in more detail, a more particular description of the embodiments of the disclosure, briefly summarized below, may be had by reference to the appended drawings, which are not intended to be limiting of the embodiments of the disclosure. In the following description of the technology, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, one or more embodiments may still be practiced without these details. In other instances, well-known structures and devices may be shown simplified in order to simplify the drawing.

The terms first, second and the like in the description and in the claims of the embodiments of the disclosure and in the above-described figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate in order to describe embodiments of the present disclosure. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion.

In the embodiments of the present disclosure, the terms "upper", "lower", "inner", "middle", "outer", "front", "rear", and the like indicate an azimuth or a positional relationship based on that shown in the drawings. These terms are used primarily to better describe embodiments of the present disclosure and embodiments thereof and are not intended to limit the indicated device, element, or component to a particular orientation or to be constructed and operated in a particular orientation. Also, some of the terms described above may be used to indicate other meanings in addition to orientation or positional relationships, for example, the term "upper" may also be used to indicate some sort of attachment or connection in some cases. The specific meaning of these terms in this embodiment will be understood by those of ordinary skill in the art as appropriate.

In addition, the terms "disposed," "connected," "secured" and "affixed" are to be construed broadly. For example, "connected" may be in a fixed connection, a removable connection, or a unitary construction; may be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements, or components. The specific meaning of the above terms in the present embodiment can be understood by those of ordinary skill in the art according to the specific circumstances.

The term "plurality" means two or more, unless otherwise indicated.

The term "and/or" is an associative relationship that describes an object, meaning that there may be three relationships. For example, a and/or B, represent: a or B, or, A and B.

It should be noted that, without conflict, the embodiments of the present embodiments and features of the embodiments may be combined with each other.

Referring to fig. 1, the present embodiment provides a water chiller, which includes a refrigeration system, a cooling water pipe and a freezing water pipe, wherein the refrigeration system includes a condenser 10, an evaporator 20, a compressor 30 and a throttling device 40, and the condenser 10, the evaporator 20, the compressor 30 and the throttling device 40 are communicated through refrigerant pipelines. A check valve 60 is arranged between the compressor 30 and the condenser 10, and the check valve 60 can prevent the refrigerant in the condenser 10 from flowing back to the compressor 30 so as to realize the refrigeration of the refrigeration system. The refrigerant evaporates in the evaporator 20, the chilled water pipe exchanges heat with the refrigerant in the evaporator 20, the refrigerant evaporates to absorb heat, the temperature of the water in the chilled water pipe is reduced after the water exchanges heat with the refrigerant, and the chilled water pipe can be transported to a place needing refrigeration for refrigeration, such as being transported to a room for refrigeration. The refrigerant is condensed in the condenser 10, the cooling water pipe exchanges heat with the refrigerant in the condenser 10, the refrigerant condenses and releases heat, the temperature of water in the cooling water pipe rises after the heat exchange between the water and the refrigerant, the temperature of the refrigerant in the condenser 10 decreases, the circulation of the refrigerant in a refrigerating system is further ensured, and the water temperature of the cooling water pipe rises and is conveyed into a cooling tower for cooling.

In fig. 1, thick arrows indicate the flow direction of the refrigerant, and thin arrows indicate the flow directions of the cooling water and the chilled water.

In this embodiment, the cooling water pipe includes a main cooling water inlet pipeline 101 and an auxiliary cooling water inlet pipeline 102 which are arranged in parallel, the chilled water pipe includes a main chilled water inlet pipeline 201 and an auxiliary chilled water inlet pipeline 202 which are arranged in parallel, the condenser 10 is provided with a cooling water inlet and a cooling water outlet, and the main cooling water inlet pipeline 101 and the auxiliary cooling water inlet pipeline 102 are both communicated with a cooling water source and the cooling water inlet; the evaporator 20 is provided with a freezing water inlet and a freezing water outlet, and the main freezing water inlet pipeline 201 and the auxiliary freezing water inlet pipeline 202 are both communicated with a freezing water source and the freezing water inlet; the cooling water pipe further comprises a cooling water outlet pipeline 103, the cooling water pipe further comprises a cooling water outlet pipeline 203, the cooling water outlet pipeline 103 is communicated with the cooling water outlet, and the cooling water outlet pipeline 203 is communicated with the cooling water outlet.

The main cooling water inlet pipeline 101 and the auxiliary cooling water inlet pipeline 102 are used for conveying water of a cooling water source to a cooling water inlet, the cooling water inlet is used for supplying the water of the cooling water source into the condenser 10 and exchanging heat with a refrigerant in the condenser 10, and the cooling water outlet pipeline 103 discharge the cooling water after heat exchange to the outside of the condenser 10; the main freezing water inlet pipeline 201 and the auxiliary freezing water inlet pipeline 202 are used for conveying water of a freezing water source to the freezing water inlet, the freezing water inlet is used for supplying the water of the freezing water source into the evaporator 20 and exchanging heat with a refrigerant in the evaporator 20, and the freezing water outlet pipeline 203 is used for discharging the frozen water after heat exchange to the outside of the evaporator 20.

In a specific embodiment, the water inlet of the auxiliary cooling water inlet pipeline 102 is communicated with the main cooling water inlet pipeline 101, water of a cooling water source in the main cooling water inlet pipeline 101 can flow into the auxiliary cooling water inlet pipeline 102, the water outlet of the auxiliary cooling water inlet pipeline 102 is communicated with the cooling water inlet, namely, the water of the cooling water source flows into the main cooling water inlet pipeline 101 and is split, one part still flows into the cooling water inlet along the main cooling water inlet pipeline 101, and the other part flows into the cooling water inlet along the auxiliary cooling water inlet pipeline 102; likewise, the water inlet of the auxiliary freezing water inlet pipeline 202 is communicated with the main freezing water inlet pipeline 201, water of a freezing water source in the main freezing water inlet pipeline 201 can flow into the auxiliary freezing water inlet pipeline 202, the water outlet of the auxiliary freezing water inlet pipeline 202 is communicated with the freezing water inlet, namely, after flowing into the main freezing water inlet pipeline 201, a part of the water flows into the freezing water inlet along the main freezing water inlet pipeline 201, and the other part flows into the freezing water inlet along the auxiliary freezing water inlet pipeline 202.

In this embodiment, the chiller further includes a first regulator valve 1011, a second regulator valve 1021, a third regulator valve 2011, and a fourth regulator valve 2012. The first adjusting valve 1011 is disposed on the main cooling water inlet pipeline 101 and is used for adjusting the on-off of the main cooling water inlet pipeline 101, and the second adjusting valve 1021 is disposed on the auxiliary cooling water inlet pipeline 102 and is used for adjusting the on-off of the auxiliary cooling water inlet pipeline 102. By adjusting the opening degrees of the first and

second adjusting valves

1011 and 1021, the flow rates of the water flowing into the cooling water inlets of the main cooling water inlet pipe 101 and the auxiliary cooling water inlet pipe 102, respectively, can be adjusted to adjust the water temperature flowing into the cooling water inlets, thereby adjusting the pressure of the condenser 10.

The third regulating valve 2011 is disposed on the main freezing water inlet pipeline 201 and is used for regulating the flow of water in the main freezing water inlet pipeline 201, and the fourth regulating valve 2021 is disposed on the auxiliary freezing water inlet pipeline 202 and is used for regulating the flow of water in the auxiliary freezing water inlet pipeline 202. By adjusting the opening degrees of the third adjusting valve 2011 and the fourth adjusting valve 2021, the flow rates of the water flowing into the freezing water inlet port by the main freezing water inlet line 201 and the auxiliary freezing water inlet line 202, respectively, can be adjusted to adjust the water temperature flowing into the freezing water inlet port, thereby adjusting the pressure of the evaporator 20.

In this embodiment, the auxiliary cooling water inlet pipe 102 is in contact with or connected to the auxiliary freezing water inlet pipe 202, and when both the second regulator valve 1021 and the fourth regulator valve 2021 are opened, the cooling water in the auxiliary cooling water inlet pipe 102 exchanges heat with the freezing water in the auxiliary freezing water inlet pipe 202 to regulate the water temperatures of the cooling water pipe and the freezing water pipe. By adjusting the water temperatures of the cooling water pipe and the freezing water pipe, the pressure in the evaporator 20 and the condenser 10 can be simultaneously adjusted, the effect of reducing the pressure ratio can be improved, and the surge can be prevented better.

In practical applications, the pressure of the condenser 10 is proportional to the condensation temperature, wherein the pressure of the condenser 10 refers to the pressure of the refrigerant condensed from gas into liquid in the condenser 10, the condensation temperature refers to the saturation temperature of the gaseous refrigerant in the condenser 10 when condensed under a certain pressure, and factors influencing the condensation temperature include the cooling water temperature, the cooling water flow rate, the size of the heat transfer area of the condenser 10 and the cleanliness, wherein the condensation temperature is mainly limited by the cooling water temperature, and the condensation temperature is positively related to the cooling water temperature; similarly, the pressure of the evaporator 20 is proportional to the evaporation temperature, the pressure of the evaporator 20 refers to the pressure of the refrigerant evaporating from the liquid into the gas in the evaporator 20, the evaporation temperature refers to the saturation temperature of the liquid refrigerant evaporating at a certain pressure in the evaporator 20, and factors affecting the evaporation temperature include the thermal load of the chilled water (i.e., the chilled water temperature), the heat transfer area of the evaporator 20, and the capacity of the compressor 30, wherein the evaporation temperature is positively correlated with the chilled water temperature.

In summer, when the temperature of the chilled water is lower than the temperature of the cooling water, the second proportional valve 1021 and the fourth proportional valve 2021 are controlled to be opened, so that the cooling water of the auxiliary cooling water inlet pipeline 102 exchanges heat with the chilled water of the auxiliary cooling water inlet pipeline 202, the cooled chilled water after the heat exchange flows into the condenser 10, and similarly, the chilled water after the heat exchange flows into the evaporator 20 after the temperature is raised, and then flows into the evaporator 20, thereby reducing the pressure of the condenser 10, improving the pressure of the evaporator 20 and realizing the effect of reducing the pressure ratio.

In winter, when the temperature of the cooling water is about 0 ℃, some factories also use a water chilling unit to cool the equipment. At this time, the low temperature of the cooling water may result in low unit pressure, which may result in a cold water unit that is not started, or may be reversed after the cold water unit is started, which is not beneficial to cooling the refrigerant of the compressor 30. At this time, the second proportional valve and the fourth proportional valve can be controlled to be opened, so that the cooling water of the auxiliary cooling water inlet pipeline 102 exchanges heat with the chilled water of the auxiliary freezing water inlet pipeline 202, and thus under the condition that the chilled water temperature in winter is far higher than the cooling water temperature, the auxiliary cooling water inlet pipeline 102 exchanges heat with the auxiliary freezing water inlet pipeline 202, the temperature of the cooling water is raised, the temperature of the chilled water is reduced, and the problems that the chiller cannot be started and the running is reversed after the chiller cannot be started are avoided.

Optionally, the first, second, third and

fourth regulating valves

1011, 1021, 2011, 2021 are PID proportional regulating valves, and the compressor 30 is a gas suspension compressor 30, a gas-liquid suspension compressor 30, a magnetic suspension compressor 30 or other centrifugal compressor 30.

Optionally, the water chiller further includes a heat exchange device 50, the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 are connected through the heat exchange device 50, and water in the auxiliary cooling water inlet pipeline 102 and water in the auxiliary freezing water inlet pipeline 202 can exchange heat through the heat exchange device 50.

The water of the auxiliary cooling water inlet pipeline 102 and the water of the auxiliary freezing water inlet pipeline 202 exchange heat through the heat exchange device 50, so that the heat exchange efficiency of the water of the auxiliary cooling water inlet pipeline 102 and the water of the auxiliary freezing water inlet pipeline 202 is improved.

Alternatively, the heat exchange device 50 may be a plate heat exchanger, which has long service life, better economic benefit, higher reliability, and can provide stability of the water chiller.

Alternatively, the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 may be in winding contact with each other, and heat exchange between the water in the auxiliary cooling water inlet pipeline 102 and the water in the auxiliary freezing water inlet pipeline 202 is achieved through the winding contact.

Optionally, the water outlet of the auxiliary cooling water inlet pipeline 102 is communicated with the main cooling water inlet pipeline 101, so that the water of the auxiliary cooling water inlet pipeline 102 and the water of the main cooling water inlet pipeline 101 flow into the cooling water inlet after being mixed.

The water flowing out from the water outlet of the auxiliary cooling water inlet pipeline 102 flows back into the main cooling water inlet pipeline 101, and flows into the cooling water inlet after being mixed in the main cooling water inlet pipeline 101, so that the mixing time of the water of the auxiliary cooling water inlet pipeline 102 and the water of the main cooling water inlet pipeline 101 is increased. By the arrangement, the water temperature of the auxiliary cooling water inlet pipeline 102 and the water temperature of the main cooling water inlet pipeline 101 are uniformly mixed and then flow into the cooling water inlet, so that the water temperature flowing into the cooling water pipe is prevented from being uneven.

Optionally, the water outlet of the auxiliary freezing water inlet pipeline 202 is communicated with the main freezing water inlet pipeline 201, so that the water of the auxiliary freezing water inlet pipeline 202 and the water of the main freezing water inlet pipeline 201 flow into the freezing water inlet after being mixed.

The water flowing out of the water outlet of the auxiliary freezing water inlet pipeline 202 flows back into the main freezing water inlet pipeline 201, and flows into the freezing water inlet after being mixed in the main freezing water inlet pipeline 201, so that the mixing time of the water of the auxiliary freezing water inlet pipeline 202 and the water of the main freezing water inlet pipeline 201 is increased. By the arrangement, the water temperature of the auxiliary freezing water inlet pipeline 202 and the water temperature of the main freezing water inlet pipeline 201 are uniformly mixed and then flow into the freezing water inlet, so that the non-uniform water temperature of the water flowing into the freezing water pipe is avoided.

In this embodiment, the auxiliary cooling water inlet pipe 102 and the auxiliary freezing water inlet pipe 202 can exchange heat, on the one hand, the temperature of the cooling water can be reduced, the condensing pressure can be reduced, and the pressure of the evaporator 20 can be increased when the temperature of the freezing water is lower than that of the cooling water in summer, so that the pressure ratio between the condenser 10 and the evaporator 20 can be reduced. The reduced pressure ratio results in a better unloading capacity of the compressor 30, a reduced risk of surging, and an increased compressor load at low loads, which is more resistant to surging. Meanwhile, under the condition that the temperature of the chilled water is far higher than that of the cooling water in winter, the temperature of the cooling water is increased, the temperature of the chilled water is reduced, and the problems that the water chilling unit cannot be started and the water chilling unit reversely rotates after being started are solved. On the other hand, the flow rate of the cooling water is adjusted by the first adjusting valve 1011 and the second adjusting valve 1021 and then flows into the condenser 10, and the flow rate of the chilled water is adjusted by the third adjusting valve 2011 and the fourth adjusting valve 2021 and then flows into the evaporator 20, and the condensing pressure of the condenser 10 can be reduced in summer, and the pressure of the evaporator 20 can be increased, so that the effect of reducing the pressure ratio between the condenser 10 and the evaporator 20 can be improved, and the surge prevention effect can be improved.

With reference to fig. 2, this embodiment further provides a method for controlling a water chiller, including:

s201, the water chilling unit acquires the operation parameters.

S202, when the running parameters of the water chilling unit meet the set conditions, the water chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to be opened, so that cooling water in the auxiliary cooling water inlet pipeline 102 and chilled water in the auxiliary chilled water inlet pipeline 202 exchange heat, and the water temperatures of the cooling water pipe and the chilled water pipe are regulated; wherein the initial states of the second regulator valve 1021 and the fourth regulator valve 2021 are open.

The cooling water of the auxiliary cooling water inlet pipeline 102 exchanges heat with the chilled water of the auxiliary freezing water inlet pipeline 202 to adjust the water temperatures of the cooling water pipe and the chilled water pipe, so that the pressure of the evaporator 20 and the condenser 10 can be simultaneously adjusted, the effect of reducing the pressure ratio of the water chiller is improved, and the surge is better prevented.

Optionally, the operation parameters of the water chiller include: the pressure ratio r between the condenser 10 and the evaporator 20, the load of the compressor, the temperature of the chilled water, the temperature of the cooling water, etc. The water chiller acquires the parameters through the sensors, and controls the second regulating valve 1021 and the fourth regulating valve 2021 to be opened according to the parameters; in this embodiment, according to the parameters of the water chiller, the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be opened, so that the communication between the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 matches the parameters of the water chiller, and the evaporation pressure of the evaporator 20 can be increased while the condensation pressure of the condenser 10 is reduced under the condition that the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 are controlled to be communicated, so that the effect of reducing the pressure ratio between the condenser 10 and the evaporator 20 is improved, and the effect of preventing surging is further improved.

Alternatively, as shown in fig. 3, in a case where the operation parameters of the water chiller meet the set conditions, the water chiller controls both the second regulator valve 1021 and the fourth regulator valve 2021 to be opened, including:

s301, the water chiller acquires a pressure ratio r between the condenser 10 and the evaporator 20, a temperature of cooling water and a temperature of chilled water.

S302, when the temperature of the cooling water is higher than that of the chilled water, and r is larger than r ₁ In the case of (a), the chiller controls both the second regulator valve 1021 and the fourth regulator valve 2021 to be opened.

r is the pressure ratio between the condenser 10 and the evaporator 20, r ₁ Is a first pressure ratio threshold. If r > r ₁ The pressure ratio is higher than the unloading pressure ratio, and if the pressure ratio is not reduced, the water chilling unit is at risk of shutdown. In this case, the second regulator valve 1021 and the fourth regulator valve 2021 are both opened, and the water temperature of the auxiliary cooling water inlet pipe 102 is increased and the water temperature of the auxiliary cooling water inlet pipe 202 is decreased after the water of the auxiliary cooling water inlet pipe 102 exchanges heat with the water of the auxiliary freezing water inlet pipe 202 due to the low water temperature of the auxiliary cooling water inlet pipe 102The temperature of the cooling water inlet is reduced, the pressure of the condenser 10 can be reduced, the water temperature of the chilled water inlet is increased, and the pressure of the evaporator 20 is increased, so that the purpose of reducing the pressure ratio is achieved. If r is less than or equal to r ₁ In this case, the second regulator valve 1021 and/or the fourth regulator valve 2021 may be maintained in the current off state. The first pressure ratio threshold r ₁ Can be determined according to actual needs, and the present embodiment does not limit it in any way.

In the present embodiment, the magnitude relation between the pressure ratio value between the condenser 10 and the evaporator 20 and the first threshold value is compared to control the opening of both the second regulator valve 1021 and the fourth regulator valve 2021, thereby preventing the high pressure ratio of the chiller, and improving the surge prevention effect.

Alternatively, as shown in fig. 4, in a case where the operation parameters of the water chiller meet the set conditions, the water chiller controls both the second regulator valve 1021 and the fourth regulator valve 2021 to be opened, including:

s401, the water chiller acquires a pressure ratio r between the condenser 10 and the evaporator 20, a temperature of cooling water and a temperature of chilled water.

S402, when the temperature of the cooling water is higher than that of the chilled water, and r is larger than r ₁ In the case of (1), the chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to be opened to a preset opening degree; wherein the preset opening degree is smaller than the maximum opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021.

At r > r ₁ In the case of (2), the water chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to be opened to the preset opening degrees, thereby causing the auxiliary cooling water intake line 102 and the auxiliary freezing water intake line 202 to communicate. The second regulator valve 1021 and the fourth regulator valve 2021 are first opened to a preset opening degree, which is the initial opening degree of the second regulator valve 1021 and the fourth regulator valve 2021. The opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021 are adjusted to be maintained at the preset opening degrees for a first preset period of time to reduce the pressure ratio.

Optionally, in combination with fig. 5, in a case where the operation parameters of the water chiller meet the set conditions, the water chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to be opened, including:

s501, the chiller acquires the pressure ratio r between the condenser 10 and the evaporator 20, the temperature of the cooling water, and the temperature of the chilled water.

S502, when the temperature of the cooling water is higher than that of the chilled water, and r is larger than r ₁ In the case of (1), the chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to be opened to a preset opening degree; wherein the preset opening degree is smaller than the maximum opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021.

S503, at r ₂ <r＜r ₁ In the case of (a), the water chiller controls the second regulating valve and the fourth regulating valve to increase the opening degree and/or controls the first regulating valve and the second regulating valve to decrease the opening degree so as to enable the pressure ratio r to be the same as the pressure ratio r ₃ ≤r≤r ₂ The method comprises the steps of carrying out a first treatment on the surface of the Wherein r is ₂ R is the second pressure ratio threshold ₃ As a result of the second pressure ratio threshold value, _r1 ＞r ₂ ＞r ₃ 。

at r > r ₁ In the case of (2), the water chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to be opened to the preset opening degrees, thereby causing the auxiliary cooling water intake line 102 and the auxiliary freezing water intake line 202 to communicate. The second regulator valve 1021 and the fourth regulator valve 2021 are first opened to a preset opening degree, which is the initial opening degree of the second regulator valve 1021 and the fourth regulator valve 2021. Adjusting the opening degree of the second regulator valve 1021 and the fourth regulator valve 2021 to maintain the preset opening degree for a first preset period of time to reduce the pressure ratio, and after adjusting the opening degree of the second regulator valve 1021 and the fourth regulator valve 2021 to maintain the preset opening degree for the first preset period of time, after r ₂ <r＜r ₁ In the case of (1), the opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021 are increased, and the opening degrees of the first regulator valve 1011 and the third regulator valve 2011 are decreased to make the pressure ratio r ₃ ≤r≤r ₂ 。r ₂ The second pressure ratio threshold is a target pressure ratio and is also an ideal pressure ratio for preventing surge. Second pressure ratio threshold r ₂ The first preset duration and the first preset opening degree can be determined according to actual needs, and the embodiment does not limit the first preset duration and the first preset opening degree.

In this embodiment, the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be opened to a preset opening degree, so that the cooling water in the auxiliary cooling water inlet pipeline 102 and the chilled water in the auxiliary chilled water inlet pipeline 202 exchange heat, and thus the pressure ratio is primarily reduced, but the reduction amplitude is smaller, so as to avoid larger fluctuation of the operation of the chiller. After a certain period of time, the opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021 are increased, and/or the opening degrees of the first regulator valve 1011 and the third regulator valve 2011 are decreased, so that the pressure ratio r is maintained at r ₂ Thereby reducing the pressure ratio to the desired pressure ratio to reduce the probability of surge of the compressor 30. After the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 are communicated, the opening degrees of the first regulating valve 1011, the second regulating valve 1021, the third regulating valve 2011 and the fourth regulating valve 2021 are controlled through a PID control algorithm, and the pressure ratio value between the condenser 10 and the evaporator 20 is continuously monitored.

Optionally, referring to fig. 6, another control method of a water chiller is provided in an embodiment of the present disclosure, including:

s601, the water chiller acquires a pressure ratio r between the condenser 10 and the evaporator 20, a temperature of cooling water and a temperature of chilled water.

S602, at r<r ₃ In the case of (a), the chiller controls the second regulator valve 1021 and/or the fourth regulator valve 2021 to be opened.

When r is less than r ₃ When the pressure ratio is low enough, the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 are controlled to be disconnected, the flow rate of water in the main cooling water inlet pipeline 101 is increased, the water temperature of the cooling water pipe is increased, the flow rate of water in the main freezing water inlet pipeline 201 is increased, and the water temperature of the freezing water pipe is reduced, so that the energy consumption of a water chilling unit is saved.

Specifically, as shown in fig. 7, the present embodiment provides another method for controlling a water chiller, including:

S701, the chiller acquires the pressure ratio r between the condenser 10 and the evaporator 20, the temperature of the cooling water, and the temperature of the chilled water.

S702, when the temperature of the cooling water is higher than that of the chilled water and r is larger than r ₁ Under the condition of (1), the water chilling unit controls the second regulatorThe throttle valve 1021 and the fourth regulator valve 2021 are opened to preset opening degrees.

S703, at r ₂ <r＜r ₁ In the case of (a), the chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to increase the opening degree, and/or controls the first regulator valve 1011 and the third regulator valve 2011 to decrease the opening degree, so that the pressure ratio r is set ₃ ≤r≤r ₂ ；

S704, in the process of controlling the second regulating valve 1021 and the fourth regulating valve 2021 to increase the opening degree and/or controlling the first regulating valve 1011 and the third regulating valve 2011 to reduce the opening degree of the water chiller, r is smaller than r ₃ In the case of (1), the chiller controls the second regulator valve 1021 and/or the fourth regulator valve 2021 to be opened;

s705, after the chiller executes S701, at r<r3, maintaining the current state of the water chilling unit; wherein r is ₁ R is the first pressure ratio threshold ₂ R is the second pressure ratio threshold ₃ R is the third pressure ratio threshold ₁ ＞r ₂ ＞r ₃ 。

A pressure ratio r between the condensing pressure of the condenser 10 and the evaporating pressure of the evaporator 20 is obtained. At r > r ₁ In the case of (a), the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be opened. The second regulator valve 1021 and the fourth regulator valve 2021 are first opened to a preset opening degree, which is the initial opening degree of the second regulator valve 1021 and the fourth regulator valve 2021. After the opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021 are maintained for the first preset time period at the preset opening degrees, the opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021 are continuously increased, and the opening degrees of the first regulator valve 1011 and the second regulator valve 1021 are reduced. In an ideal case, the pressure ratio r can be made to reach r by adjusting the opening degrees of the first regulator valve 1011, the second regulator valve 1021, the third regulator valve 2011, and the fourth regulator valve 2021 by a PID control algorithm ₂ . In this case, the opening degree of the regulating valve is regulated so that the pressure ratio r is maintained at r ₂ And (3) obtaining the product. In another case, in the process of adjusting the opening of the adjusting valve, the pressure ratio r is reduced too much, i.e. to be smaller than r ₃ In order to maintain the pressure ratio r at r ₂ The pressure ratio r still drops and decreases during the course of (2)As low as less than r ₃ In this case, in order to prevent the pressure ratio r from continuing to decrease, the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be opened, and the decrease of the pressure ratio value is stopped. r is (r) ₂ R is the second pressure ratio threshold ₃ R is the third pressure ratio threshold ₁ ＞r ₂ ＞r ₃ Here, r ₁ Since the warning value of the pressure ratio is at least a value to be reached in order to prevent surging of the compressor 30, the pressure ratio is reduced to r when the pressure ratio is reduced ₂ Enough rising space is reserved for the pressure ratio value, so that the compressor 30 is kept from surging as long as possible, and the water chilling unit is kept to stably operate for a long time.

If r is less than or equal to r after the chiller acquires the pressure ratio r between the condenser 10 and the evaporator 20 ₁ Indicating that the pressure ratio is within the safe range, the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to continue to remain open without decreasing the pressure ratio.

The second pressure ratio threshold r ₂ Third pressure ratio threshold r ₃ The first preset duration and the first preset duration can be determined according to actual needs, and the embodiment does not limit the first preset duration.

In the present embodiment, by controlling the opening degrees of the first, second, third, and

fourth regulator valves

1011, 1021, 2011, 2021, the pressure ratio between the condenser 10 and the evaporator 20 can be reduced, thereby reducing the risk of surge of the compressor 30. When r is less than r ₃ At this time, the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be closed to prevent the pressure ratio from continuing to decrease.

Optionally, the operating parameters of the chiller include the unloading capacity of the chiller, the load of the compressor, the temperature of the cooling water, and the temperature of the chilled water.

In this embodiment, the chiller acquires the above parameters through the sensor, and controls the second regulator valve 1021 and the fourth regulator valve 2021 to be opened according to the above parameters; in this embodiment, according to the parameters of the water chiller, the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be opened, so that the communication between the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 matches the parameters of the water chiller, and the temperature of the chilled water and the load of the compressor are improved under the condition that the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 are controlled to be communicated, so that the surge prevention effect is improved.

Alternatively, as shown in fig. 8, in the case where the operation parameters of the water chiller meet the set conditions, controlling both the second regulator valve 1021 and the fourth regulator valve 2021 to be opened includes:

s801, the chiller acquires unloading capacity, load of a compressor, temperature of cooling water and temperature of chilled water.

S802, when the temperature of the chilled water is smaller than the temperature of the cooling water, the unloading capacity of the water chiller is minimum, the temperature of the chilled water is lower than the target temperature, the difference between the temperature of the chilled water and the target temperature is smaller than the shutdown temperature difference, and the load of the compressor is smaller than the target load, the water chiller controls the second regulating valve 1021 and the fourth regulating valve 2021 to be opened.

The unloading capacity of the water chiller, the load of the compressor, the temperature of the cooling water and the temperature of the chilled water are obtained. When the unloading capacity of the chiller reaches a minimum, the temperature of the chilled water is below the target temperature, and the difference between the temperature of the chilled water and the target temperature has not reached the shutdown temperature difference, i.e., is less than the shutdown temperature difference, there is a risk of surging the compressor 30 if the compressor 30 is still continuously loaded for a small amount. In this case, both the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be opened, so that the temperature of chilled water can be increased, the load of the compressor is increased, and the risk of surging of the compressor 30 is reduced. The unloading capacity of the water chilling unit reaches the minimum specifically as follows: the compressor 30 is unloaded until the output capacity of the compressor 30 is minimized, and the power, rotation speed, and current of the compressor 30 can be considered as the minimum values under the corresponding conditions, at which time the output capacity of the compressor 30 cannot be reduced any more.

It should be noted that the target temperature may be determined according to actual needs, and the present embodiment is not limited thereto.

Optionally, in conjunction with fig. 9, the chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to be both open, including:

s901, a water chiller acquires unloading capacity, load of a compressor, temperature of cooling water and temperature of chilled water.

S902, in the case where the temperature of the chilled water is less than the temperature of the cooling water, the unloading capacity of the water chiller reaches the minimum, the temperature of the chilled water is less than the target temperature, the difference between the temperature of the chilled water and the target temperature is less than the shutdown temperature difference, and the load of the compressor is less than the target load, the water chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to open to the preset opening.

And when the unloading capacity of the water chiller reaches the minimum, the temperature of the chilled water is lower than the target temperature, the difference between the temperature of the chilled water and the target temperature is smaller than the shutdown temperature difference, and the load of the compressor is smaller than the target load, the second regulating valve 1021 and the fourth regulating valve 2021 are controlled to be opened. The second regulator valve 1021 and the fourth regulator valve 2021 are regulated to be opened first to a preset opening degree, which is an initial opening degree of the second regulator valve 1021 and the fourth regulator valve 2021. The opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021 are adjusted to maintain the second preset opening degree for a second preset period of time to raise the temperature of the chilled water and raise the load of the compressor.

Optionally, in conjunction with fig. 10, the chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to be both open, including:

s1001, the chiller acquires unloading capacity, load of a compressor, temperature of cooling water and temperature of chilled water.

S1002, in the case where the temperature of the chilled water is less than the temperature of the cooling water, the unloading capacity of the water chiller reaches the minimum, the temperature of the chilled water is less than the target temperature, the difference between the temperature of the chilled water and the target temperature is less than the shutdown temperature difference, and the load of the compressor is less than the target load, the water chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to open to the preset opening.

S1003, when the adjusted chilled water temperature is less than the target temperature, the chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to increase the opening degree, and/or controls the first regulator valve 1011 and the third regulator valve 2011 to decrease the opening degree, so that the chilled water temperature is maintained at the target temperature, and the load of the compressor is maintained at the target load.

In the case where the unloading capacity of the chiller is minimized, the temperature of the chilled water is lower than the target temperature, and the difference between the temperature of the chilled water and the target temperature is smaller than the shutdown temperature difference, and the load of the compressor is smaller than the target load, the compressor 30 has a surge risk, and the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be opened. The second regulator valve 1021 and the fourth regulator valve 2021 are regulated to be opened first to a second preset opening degree, which is the initial opening degree of the second regulator valve 1021 and the fourth regulator valve 2021. After the opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021 are adjusted for the second preset time period at the second preset opening degree, the opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021 are continuously adjusted, so that the temperature of the chilled water and the load of the compressor are increased, the temperature of the chilled water is kept at the target temperature, and the load of the compressor is kept at the target load. It should be noted that, the second preset duration, the target temperature, and the target load may all be determined according to actual needs, which is not limited in this embodiment.

In this embodiment, the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be opened to a preset opening degree, so that the water in the auxiliary cooling water inlet pipeline 102 and the water in the auxiliary freezing water inlet pipeline 202 circulate, and the temperature of the chilled water and the load of the compressor are primarily improved, but the improvement amplitude is smaller, so that the operation of the chiller is prevented from greatly fluctuating. After a certain period of time, the opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021 are increased, and/or the opening degrees of the first regulator valve 1011 and the third regulator valve 2011 are decreased, so that the temperature of the chilled water and the load of the compressor are further increased and maintained at the target temperature and the target load, thereby reducing the risk of surging of the compressor 30.

Optionally, the present embodiment provides another method for controlling a water chiller, including:

when the temperature of the chilled water is less than the temperature of the cooling water, the unloading capacity of the water chiller is minimized, the temperature of the chilled water is less than the target temperature, and the difference between the temperature of the chilled water and the target temperature is less than the shutdown temperature difference, the water chiller controls both the second regulator valve 1021 and the fourth regulator valve 2021 to be opened.

In the case where the temperature of the chilled water is greater than the target temperature and the load of the compressor is greater than the load threshold, the chiller controls the second regulator valve 1021 and/or the fourth regulator valve 2021 to be opened.

After the second regulator valve 1021 and the fourth regulator valve 2021 are opened, the opening degrees of the first regulator valve 1011, the second regulator valve 1021, the third regulator valve 2011, and the fourth regulator valve 2021 are controlled and adjusted by a PID control algorithm. The chilled water temperature and compressor load are continuously monitored. When the temperature of the chilled water is greater than the target temperature and the load of the compressor is greater than the load threshold, the second regulator valve 1021 and the fourth regulator valve 2021 are closed.

Specifically, as shown in fig. 11, the present embodiment provides another method for controlling a water chiller, including:

s1101, the chiller acquires its unloading capacity, the load of the compressor, the temperature of the cooling water, and the temperature of the chilled water.

S1102, when the temperature of the chilled water is less than the temperature of the cooling water, the unloading capacity of the chiller reaches a minimum, the temperature of the chilled water is less than the target temperature, the difference between the temperature of the chilled water and the target temperature is less than the shutdown temperature difference, and the load of the compressor is less than the target load, the chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to open to a preset opening.

S1103, when the adjusted chilled water temperature is less than the target temperature, the chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to increase the opening degree, and/or controls the first regulator valve 1011 and the third regulator valve 2011 to decrease the opening degree, so that the chilled water temperature is maintained at the target temperature, and the load of the compressor is maintained at the target load.

In S1104, in the process of controlling the second regulator valve 1021 and the fourth regulator valve 2021 to increase the opening degree and/or controlling the first regulator valve 1011 and the third regulator valve 2011 to decrease the opening degree, in the case where the temperature of the chilled water is greater than the target temperature and the load of the compressor is greater than the load threshold, the second regulator valve 1021 and/or the fourth regulator valve 2021 is/are controlled to be turned off by the chiller.

S1105, after the chiller executes S1101, the chiller maintains the current state when the temperature of the chilled water is greater than the target temperature and the load of the compressor is greater than the load threshold.

The unloading capacity of the water chiller, the load of the compressor, the temperature of the cooling water and the temperature of the chilled water are obtained. In the case where the temperature of the chilled water is less than the temperature of the cooling water, the load of the compressor is less than or equal to the load threshold, the temperature of the chilled water is less than the target temperature, and the difference between the temperature of the chilled water and the target temperature is less than the shutdown temperature difference, the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be opened. Otherwise, the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to remain open, i.e., the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to remain closed. After the second regulator valve 1021 and the fourth regulator valve 2021 are opened, the second regulator valve 1021 and the fourth regulator valve 2021 are first opened to a preset opening degree, which is an initial opening degree of the regulator valve. After the opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021 are maintained for a second preset period of time at the preset opening degrees, the opening degrees of the second regulator valve 1021 and the fourth regulator valve 2021 are continuously adjusted, so that the temperature of chilled water and the load of the compressor are increased. In an ideal case, the opening degrees of the first, second, third, and

fourth control valves

1011, 1021, 2011, 2021 are adjusted by a PID control algorithm, so that the temperature of the chilled water can be brought to a target temperature, and the load of the compressor can be brought to a target load. In this case, the opening degrees of the first regulator valve 1011, the second regulator valve 1021, the third regulator valve 2011, and the fourth regulator valve 2021 may be adjusted so that the temperature of the chilled water is maintained at the target temperature and the load of the compressor is maintained at the target load. In another case, the temperature of the chilled water is excessively increased and exceeds the target temperature in the process of adjusting the opening of the above-mentioned adjusting valve, or the temperature of the chilled water is still increased in the process of maintaining the temperature of the chilled water at the target temperature. In this case, when the load of the compressor is greater than the load threshold, the second regulator valve 1021 and/or the fourth regulator valve 2021 are/is controlled to be opened in order to prevent the temperature of the chilled water from continuously increasing, that is, the second regulator valve 1021 and the fourth regulator valve 2021 are slowly closed, and the increase of the temperature of the chilled water and the load of the compressor is stopped. Optionally, the load threshold is the minimum load of the compressor 30. It should be noted that the second preset time period, the target temperature, and the target load may be determined according to actual needs, which is not limited in this embodiment.

fourth regulator valves

1011, 1021, 2011, 2022, the temperature of chilled water and the load of the compressor can be increased, thereby reducing the risk of surge of the compressor 30. After the temperature of the chilled water and the load of the compressor reach the safe range, the valve is timely regulated, so that certain energy sources can be saved.

Alternatively, in conjunction with fig. 12, in a case where the operation parameters of the water chiller meet the set conditions, controlling both the second regulator valve 1021 and the fourth regulator valve 2021 to be opened includes:

s1201, the water chiller acquires the temperature of cooling water and the temperature of chilled water.

S1202, when the temperature of the cooling water is less than the temperature of the chilled water and the temperature of the cooling water is less than the temperature threshold when the chiller is started, the chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to be opened and controls the first regulator valve 1011 and the third regulator valve 2011 to be opened.

The temperature of the cooling water and the temperature of the chilled water are obtained. In winter, when the temperature of the cooling water is about 0 ℃, some factories also use a water chilling unit to cool the equipment. In this case, when the water chiller is started, the temperature of the cooling water is low, which results in low pressure of the chiller, and thus the water chiller cannot be started, or the water chiller is reversely operated after being started, which is not beneficial to cooling the refrigerant of the compressor 30. Therefore, when the water chiller starts, if the temperature of the cooling water is lower than the temperature threshold, the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be opened, and the first regulator valve 1011 and the third regulator valve 2011 are controlled to be opened, so that the water in the auxiliary cooling water inlet pipeline 102 exchanges heat with the water in the auxiliary freezing water inlet pipeline 202, and the water temperature of the cooling water inlet is increased. In practical application, the temperature threshold is 2 ℃. Therefore, under the condition that the temperature of the chilled water is far higher than that of the cooling water in winter, the temperature of the cooling water can be increased, the temperature of the chilled water can be reduced, and the problems that the water chilling unit cannot be started and the water chilling unit can reversely run after being started are solved. And after the water chilling unit is successfully started, continuously monitoring the temperature of the cooling water and the temperature of the chilled water. In the case where the temperature of the cooling water is greater than the temperature of the chilled water, the water chiller does not have a problem of reverse rotation, and therefore both the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be opened, and both the first regulator valve 1011 and the third regulator valve 2011 are controlled to be opened.

Specifically, in connection with fig. 13, another method for controlling a water chiller is provided in this embodiment, including:

s1301, the water chiller acquires the temperature of cooling water and the temperature of chilled water.

In S1302, when the temperature of the cooling water is less than the temperature of the chilled water and the temperature of the cooling water is less than the temperature threshold when the chiller is started, the chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to be opened and controls the first regulator valve 1011 and the third regulator valve 2011 to be opened.

S1303, when the temperature of the cooling water is greater than the temperature threshold after the water chiller starts, the water chiller controls the second regulator valve 1021 and the fourth regulator valve 2021 to be opened, and controls the first regulator valve 1011 and the third regulator valve 2011 to be opened.

If the temperature of the cooling water is greater than or equal to the temperature threshold value when the water chiller is started, the water chiller controls to disconnect both the second regulator valve 1021 and the fourth regulator valve 2021, and controls both the first regulator valve 1011 and the third regulator valve 2011 to be opened, so as to save the energy consumption of the water chiller.

In this embodiment, when the chiller is started, if the temperature of the cooling water is lower than the temperature threshold, the second regulator valve 1021 and the fourth regulator valve 2021 are controlled to be opened, so that the second regulator valve 1021 and the fourth regulator valve 2021 are opened to raise the temperature of the cooling water and lower the temperature of the chilled water, thereby reducing the occurrence of the problem that the chiller cannot be started and the reverse running after the start. After the water chiller is started smoothly, if the temperature of the cooling water is higher than the temperature of the chilled water, the second regulating valve 1021 and the fourth regulating valve 2021 are controlled to be closed, so that energy sources are saved.

Referring to fig. 12, the embodiment provides an apparatus for controlling a water chiller, which includes an acquisition module and a control module. The acquisition module is configured to acquire the operation parameters of the water chilling unit; the control module is configured to control the second regulating valve 1021 and the fourth regulating valve 2021 to be opened according to the operation parameters of the water chiller; wherein the initial states of the second regulator valve 1021 and the fourth regulator valve 2021 are open.

By adopting the device for controlling a water chiller provided by the embodiment, the second regulating valve 1021 and the fourth regulating valve 2021 can be controlled to be opened according to the parameters of the water chiller, so that the on-off state of the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 are matched with the parameters of the water chiller, and the condensing pressure of the condenser 10 can be reduced while the evaporating pressure of the evaporator 20 is also improved under the condition that the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 are controlled to be communicated, thereby improving the effect of reducing the pressure ratio between the condenser 10 and the evaporator 20 and further improving the surge prevention effect.

Referring to fig. 13, the present embodiment provides an apparatus for controlling a chiller, which includes a processor (processor) 90 and a memory (memory) 901. Optionally, the apparatus may also include a communication interface (Communication Interface) 902 and a bus 903. The processor 90, the communication interface 902, and the memory 901 may communicate with each other via the bus 903. The communication interface 902 may be used for information transfer. Processor 90 may invoke logic instructions in memory 901 to perform the method for controlling a chiller in accordance with the above-described embodiments.

Further, the logic instructions in the memory 901 may be implemented in the form of a software functional unit and may be stored in a computer readable storage medium when sold or used as a separate product.

The memory 901 is a computer readable storage medium, and may be used to store a software program, a computer executable program, and program instructions/modules corresponding to the method in the present embodiment. The processor 90 executes functional applications and data processing by executing program instructions/modules stored in the memory 901, i.e., implements the method for controlling a chiller in the above-described embodiment.

The memory 901 may include a storage program area and a storage data area, wherein the storage program area may store an operating system, at least one application program required for functions; the storage data area may store data created according to the use of the terminal device, etc. Further, the memory 901 may include a high-speed random access memory 901, and may also include a nonvolatile memory 901.

The present embodiment provides a storage medium storing computer-executable instructions configured to perform the above-described method for controlling a chiller.

The storage medium may be a transitory computer readable storage medium or a non-transitory computer readable storage medium.

The above description and the drawings illustrate embodiments of the disclosure sufficiently to enable those skilled in the art to practice them. Other embodiments may involve structural, logical, electrical, process, and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in, or substituted for, those of others. Moreover, the terminology used in the present application is for the purpose of describing embodiments only and is not intended to limit the claims. As used in the description of the embodiments and the claims, the singular forms "a," "an," and "the" (the) are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, when used in this application, the terms "comprises," "comprising," and/or "includes," and variations thereof, mean that the stated features, integers, steps, operations, elements, and/or components are present, but that the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof is not precluded. Without further limitation, an element defined by the phrase "comprising one …" does not exclude the presence of other like elements in a process, method or apparatus comprising such elements. In this context, each embodiment may be described with emphasis on the differences from the other embodiments, and the same similar parts between the various embodiments may be referred to each other. For the methods, products, etc. disclosed in the embodiments, if they correspond to the method sections disclosed in the embodiments, the description of the method sections may be referred to for relevance.

Those of skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. The skilled artisan may use different methods for each particular application to achieve the described functionality, but such implementation should not be considered to be beyond the scope of the embodiments of the present disclosure. It will be clearly understood by those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, which are not repeated herein.

In the embodiments disclosed herein, the disclosed methods, articles of manufacture (including but not limited to devices, apparatuses, etc.) may be practiced in other ways. For example, the apparatus embodiments described above are merely illustrative, and for example, the division of the units may be merely a logical function division, and there may be additional divisions when actually implemented, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not performed. In addition, the coupling or direct coupling or communication connection shown or discussed with each other may be through some interface, device or unit indirect coupling or communication connection, which may be in electrical, mechanical or other form. The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to implement the present embodiment. In addition, each functional unit in the embodiments of the present disclosure may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. In the description corresponding to the flowcharts and block diagrams in the figures, operations or steps corresponding to different blocks may also occur in different orders than that disclosed in the description, and sometimes no specific order exists between different operations or steps. For example, two consecutive operations or steps may actually be performed substantially in parallel, they may sometimes be performed in reverse order, which may be dependent on the functions involved. Each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

Claims

1. A method for controlling a chiller, the chiller comprising a compressor, a condenser, and an evaporator; the condenser exchanges heat through the cooling water pipe, and the evaporator exchanges heat through the chilled water pipe; the cooling water pipe comprises a main cooling water inlet pipeline and an auxiliary cooling water inlet pipeline which are connected in parallel, and the auxiliary cooling water inlet pipeline is provided with a second regulating valve; the freezing water pipe comprises a main freezing water inlet pipeline and an auxiliary freezing water inlet pipeline which are connected in parallel, and the auxiliary freezing water inlet pipeline is provided with a fourth regulating valve; the auxiliary cooling water inlet pipeline is contacted or connected with the auxiliary freezing water inlet pipeline; the method comprises the following steps:

acquiring operation parameters of the water chilling unit;

when the running parameters of the water chilling unit meet the set conditions, the second regulating valve and the fourth regulating valve are controlled to be opened, so that cooling water in the auxiliary cooling water inlet pipeline and chilled water in the auxiliary chilled water inlet pipeline exchange heat, and the water temperatures of the cooling water pipe and the chilled water pipe are regulated;

wherein the initial states of the second regulating valve and the fourth regulating valve are disconnected;

the operation parameters of the water chilling unit comprise unloading capacity of the water chilling unit, load of a compressor, temperature of cooling water and temperature of chilled water;

The operation parameters of the water chilling unit meet the set conditions, and the method comprises the following steps:

the temperature of the cooling water is greater than that of the chilled water, the unloading capacity of the water chilling unit is minimum, the temperature of the chilled water is less than the target temperature, the difference between the temperature of the chilled water and the target temperature is less than the shutdown temperature difference, and the load of the compressor is less than the target load;

the control of the second regulating valve and the fourth regulating valve to be opened comprises:

controlling the second regulating valve and the fourth regulating valve to be opened to a preset opening degree;

the preset opening is smaller than the maximum opening of the second regulating valve and the maximum opening of the fourth regulating valve;

the main cooling water inlet pipeline is provided with a first regulating valve, the main freezing water inlet pipeline is provided with a third regulating valve, and the second regulating valve and the fourth regulating valve are controlled to be opened to a preset opening degree, and the main cooling water inlet pipeline further comprises:

controlling the second regulating valve and the fourth regulating valve to increase the opening degree and/or controlling the first regulating valve and the third regulating valve to decrease the opening degree under the condition that the temperature of the chilled water after regulation is still smaller than the target temperature, so that the temperature of the chilled water is kept at the target temperature and the load of the compressor is kept at the target load;

In the process of keeping the temperature of the chilled water at the target temperature, the temperature of the chilled water is still raised, and when the load of the compressor is greater than the load threshold, the second regulating valve and/or the fourth regulating valve is controlled to be opened.

2. The method as recited in claim 1, further comprising:

and when the temperature of the chilled water is higher than the target temperature and the load of the compressor is higher than the load threshold, controlling the second regulating valve and/or the fourth regulating valve to be disconnected, wherein the target load is higher than the load threshold.

3. An apparatus for controlling a chiller comprising a processor and a memory storing program instructions, wherein the processor is configured, when executing the program instructions, to perform the method for controlling a chiller as claimed in claim 1 or 2.

4. A water chiller comprises a compressor, a condenser, a throttling device and an evaporator which are connected in sequence; the condenser exchanges heat through the cooling water pipe, and the evaporator exchanges heat through the chilled water pipe; the method is characterized in that:

the cooling water pipe comprises a main cooling water inlet pipeline and an auxiliary cooling water inlet pipeline which are connected in parallel, and the auxiliary cooling water inlet pipeline is provided with a second regulating valve;

The freezing water pipe comprises a main freezing water inlet pipeline and an auxiliary freezing water inlet pipeline which are connected in parallel, and the auxiliary freezing water inlet pipeline is provided with a fourth regulating valve;

the auxiliary cooling water inlet pipeline is contacted or connected with the auxiliary freezing water inlet pipeline, and under the condition that the second regulating valve and the fourth regulating valve are opened, cooling water in the auxiliary cooling water inlet pipeline and freezing water in the auxiliary freezing water inlet pipeline exchange heat so as to regulate the water temperatures of the cooling water pipe and the freezing water pipe;

the water chiller further comprising a device for controlling a water chiller as set forth in claim 3 wherein the second and fourth regulating valves are each electrically connected to the device for controlling a water chiller.

5. The water chiller of claim 4, further comprising:

and the auxiliary cooling pipeline and the auxiliary freezing pipeline are connected through the heat exchange device.

6. The water chiller of claim 5, further comprising:

the first regulating valve is arranged on the main cooling water inlet pipeline;

the third regulating valve is arranged on the main freezing water inlet pipeline;

the first regulating valve and the third regulating valve are electrically connected with the device for controlling the water chilling unit.