CN113959130A

CN113959130A - Method and device for controlling water chilling unit and water chilling unit

Info

Publication number: CN113959130A
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: 2022-01-21
Anticipated expiration: 2041-10-08
Also published as: CN113959130B

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 freezing 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 with 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 operating 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, and 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 condenser pressure to the evaporator pressure 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. And the high pressure ratio can cause the faults of over current, high pressure ratio, high exhaust pressure, low suction pressure and the like of the compressor, thereby affecting the use range of the unit.

In the prior art, a surge prevention system of a centrifugal refrigerating unit is disclosed, 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 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 a refrigerant coming out of 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 refrigerating water, and cannot adjust the temperature of the cooling water, so that the effect of reducing the pressure ratio is limited, and surging cannot 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 nor is intended to identify key/critical elements or to delineate the scope of such embodiments but rather as a prelude to the more detailed description that is presented later.

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 better prevent surging.

The disclosed embodiments provide a method for controlling a chiller that includes a compressor, a condenser, and an evaporator; the condenser exchanges heat through a cooling water pipe, and the evaporator exchanges heat through a freezing 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 connected with the auxiliary freezing water inlet pipeline; the method comprises the following steps: acquiring the operating parameters of the water chilling unit; under the condition that the operating parameters of the water chilling unit meet set conditions, controlling the second regulating valve and the fourth regulating valve to be opened so that cooling water in the auxiliary cooling water inlet pipeline and chilled water in the auxiliary freezing water inlet pipeline exchange heat to regulate the water temperatures of the cooling water pipe and the chilled water pipe; wherein the second and fourth regulator valves are initially open.

The disclosed embodiment provides a device for controlling a water chilling unit, the device includes: a processor and a memory storing program instructions, the processor being configured to execute the aforementioned method for controlling a chiller when executing the program instructions.

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 sequentially connected; the condenser exchanges heat through a cooling water pipe, and the evaporator exchanges heat through a freezing 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 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 to adjust 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 controlling the second regulating valve and the fourth regulating valve to be opened according to the operating parameters of the water chilling unit under the condition that the operating parameters of the water chilling unit meet the set conditions, so that the cooling water in the auxiliary cooling water inlet pipeline exchanges heat with the chilled water in the auxiliary freezing water inlet pipeline, and the water temperatures of the cooling water pipe and the chilled water pipe are regulated. The pressure of the condenser and the pressure of the evaporator can be adjusted simultaneously by adjusting 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 adjusted, the effect of reducing the pressure ratio is improved, and the surge is prevented better.

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 in the accompanying drawings, which correspond to the accompanying drawings and not in limitation thereof, in which elements having the same reference numeral designations are shown as like elements and not in limitation thereof, and wherein:

fig. 1 is a schematic structural diagram of a water chiller according to 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 shows a method for controlling a chiller according to an embodiment of the present disclosure, where r > r₁A schematic diagram of controlling both the second and fourth regulator valves to open;

FIG. 4 is a schematic diagram of another method for controlling a chiller according to an embodiment of the present disclosure;

FIG. 5 is a schematic diagram of another method for controlling a chiller according to an embodiment of the present disclosure;

FIG. 6 shows a method for controlling a chiller, according to an embodiment of the present disclosure, at r<r₃A schematic diagram for controlling the second and/or fourth regulating valve to open;

FIG. 7 is a schematic diagram of another method for controlling a chiller according to an embodiment of the present disclosure;

fig. 8 is a schematic diagram illustrating that the second regulating valve and the fourth regulating valve are both controlled to be opened in a case where the temperature of the chilled water is lower than the temperature of the cooling water, the unloading capacity of the chiller is minimized, 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 less than the shutdown temperature difference, and the load of the compressor is less than the target load in a method for controlling a chiller according to an embodiment of the present disclosure;

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

FIG. 10 is a schematic diagram of another method for controlling a chiller according to an embodiment of the present disclosure;

FIG. 11 is a schematic diagram of another method for controlling a chiller according to an embodiment of the present disclosure;

fig. 12 is a schematic diagram illustrating that, in a method for controlling a chiller according to an embodiment of the present disclosure, when the temperature of the cooling water is lower than the temperature of the chilled water and the temperature of the cooling water is lower than the temperature threshold when the 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 diagram of another method for controlling a chiller according to 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 diagram of another device for controlling a water chilling unit 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. an auxiliary cooling water inlet pipeline; 1021. a second regulating valve; 103. cooling the 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. a freezing water outlet pipeline; 30. a compressor; 40. a throttling device; 50. a heat exchanger; 60. a one-way valve.

Detailed Description

So that the manner in which the features and elements of the disclosed embodiments can be understood in detail, a more particular description of the disclosed embodiments, briefly summarized above, may be had by reference to the embodiments, some of which are illustrated in the appended drawings. 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 be practiced without these details. In other instances, well-known structures and devices may be shown in simplified form in order to simplify the drawing.

The terms "first," "second," and the like in the description and in the claims, and the above-described drawings of embodiments of the present disclosure, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the present disclosure described herein may be made. Furthermore, the terms "comprising" and "having," as well as any variations thereof, are intended to cover non-exclusive inclusions.

In the embodiments of the present disclosure, the terms "upper", "lower", "inner", "middle", "outer", "front", "rear", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings. These terms are used primarily to better describe the disclosed embodiments and their examples and are not intended to limit the indicated devices, elements or components to a particular orientation or to be constructed and operated in a particular orientation. Moreover, some of the above terms may be used to indicate other meanings besides the orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of attachment or connection relationship in some cases. The specific meanings of these terms in the present embodiment can be understood by those of ordinary skill in the art as appropriate.

In addition, the terms "disposed," "connected," and "secured" are to be construed broadly. For example, "connected" may be a fixed connection, a detachable connection, or a unitary construction; can 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 meanings of the above terms in the present embodiment can be understood by those of ordinary skill in the art according to specific situations.

The term "plurality" means two or more unless otherwise specified.

The term "and/or" is an associative relationship that describes objects, meaning that three relationships may exist. For example, a and/or B, represents: a or B, or A and B.

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

Referring to fig. 1, the present embodiment provides a water chilling unit, where the water chilling unit includes a refrigeration system, a cooling water pipe and a chilled water pipe, 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 with each other through a refrigerant pipeline. A check valve 60 is disposed 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 refrigeration of the refrigeration system. The refrigerant evaporates in the evaporator 20, the freezing water pipe exchanges heat with the refrigerant in the evaporator 20, the refrigerant evaporates to absorb heat, the temperature of the water in the freezing water pipe is reduced after exchanging heat with the refrigerant, and the water can be transported to a place needing refrigeration for refrigeration, such as 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 is condensed to release heat, the temperature of the water in the cooling water pipe is increased after exchanging heat with the refrigerant, the temperature of the refrigerant in the condenser 10 is reduced, the circulation of the refrigerant in the refrigerating system is further ensured, and the water in the cooling water pipe is conveyed to the cooling tower for cooling after being increased in temperature.

In fig. 1, thick arrows indicate the flow direction of the refrigerant, and thin arrows indicate the flow direction 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 cooling water pipe includes a main cooling water inlet pipeline 201 and an auxiliary cooling 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 freezing water pipe further comprises a freezing water outlet pipeline 203, the cooling water outlet pipeline 103 is communicated with the cooling water outlet, and the freezing water outlet pipeline 203 is communicated with the freezing 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 allowing the water of the cooling water source to enter the condenser 10 and exchange heat with a refrigerant in the condenser 10, and the cooling water outlet pipeline 103 are used for discharging 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 a freezing water inlet, the freezing water inlet is used for allowing the water of the freezing water source to enter the evaporator 20 and exchange heat with a refrigerant in the evaporator 20, and the freezing water outlet pipeline 203 are used for discharging the freezing water after heat exchange to the outside of the evaporator 20.

In one embodiment, the inlet of the auxiliary cooling water inlet pipeline 102 is communicated with the main cooling water inlet pipeline 101, the water of the cooling water source in the main cooling water inlet pipeline 101 can flow into the auxiliary cooling water inlet pipeline 102, and 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 then is divided, one part of the water still flows into the cooling water inlet along the main cooling water inlet pipeline 101, and the other part of the water flows into the cooling water inlet along the auxiliary cooling water inlet pipeline 102; similarly, the water inlet of the auxiliary freezing water inlet pipeline 202 is communicated with the main freezing water inlet pipeline 201, the water of the freezing water source in the main freezing water inlet pipeline 201 can flow into the auxiliary freezing water inlet pipeline 202, and the water outlet of the auxiliary freezing water inlet pipeline 202 is communicated with the freezing water inlet, namely, the water of the freezing water source flows into the main freezing water inlet pipeline 201 and then is divided, one part of the water still flows into the freezing water inlet along the main freezing water inlet pipeline 201, and the other part of the water flows into the freezing water inlet along the auxiliary freezing water inlet pipeline 202.

In this embodiment, the water chilling unit further includes a first regulating valve 1011, a second regulating valve 1021, a third regulating valve 2011 and a fourth regulating valve 2012. The first adjusting valve 1011 is disposed on the main cooling water inlet pipeline 101 and used for adjusting the on-off state 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 used for adjusting the on-off state 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 main cooling water inlet 101 and the auxiliary cooling water inlet 102, respectively, can be adjusted to adjust the temperature of the water flowing into the cooling water inlet, thereby adjusting the pressure of the condenser 10.

The third adjusting valve 2011 is disposed on the main freezing water inlet line 201 for adjusting the flow of water in the main freezing water inlet line 201, and the fourth adjusting valve 2021 is disposed on the auxiliary freezing water inlet line 202 for adjusting the flow of water in the auxiliary freezing water inlet line 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 inlets respectively from the main freezing water inlet line 201 and the auxiliary freezing water inlet line 202 can be adjusted to adjust the water temperature flowing into the freezing water inlets, thereby adjusting the pressure of the evaporator 20.

In this embodiment, the auxiliary cooling water inlet pipeline 102 is in contact with or connected to the auxiliary freezing water inlet pipeline 202, and when the second adjusting valve 1021 and the fourth adjusting valve 2021 are both opened, the cooling water in the auxiliary cooling water inlet pipeline 102 exchanges heat with the freezing water in the auxiliary freezing water inlet pipeline 202 to adjust 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 pressure in the condenser 10 can be adjusted at the same time, the effect of reducing the pressure ratio is improved, and the surge is prevented better.

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

In summer, under the condition that the temperature of the chilled water is lower than that of the chilled water, the second proportional valve 1021 and the fourth proportional valve 2021 are controlled to be opened, so that the chilled water of the auxiliary cooling water inlet pipeline 102 exchanges heat with the chilled water of the auxiliary freezing water inlet pipeline 202, the chilled water after heat exchange flows into the condenser 10 after being cooled, and similarly, the chilled water after heat exchange flows into the evaporator 20 after being heated and then enters the evaporator 20, so that the pressure of the condenser 10 can be reduced, the pressure of the evaporator 20 is increased, and the effect of reducing the pressure ratio is realized.

In winter, when the temperature of cooling water is about 0 ℃, some factories need to use a water chilling unit to cool equipment. At this time, the low temperature of the cooling water may cause the unit pressure to be low, which may result in the water chiller not being started or running reversely after being started, which is not favorable for cooling the refrigerant of the compressor 30. At this time, the opening of the second proportional valve and the opening of the fourth proportional valve can be controlled to enable the cooling water of the auxiliary cooling water inlet pipeline 102 to exchange heat with the freezing water of the auxiliary freezing water inlet pipeline 202, so that the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 exchange heat under the condition that the freezing water temperature is far higher than the cooling water temperature in winter, the cooling water is heated, the temperature of the freezing water is reduced, and the problem that a water chilling unit cannot be started and runs reversely after being started is solved.

Alternatively, the first adjusting valve 1011, the second adjusting valve 1021, the third adjusting valve 2011 and the fourth adjusting valve 2021 are PID proportional adjusting valves, and the compressor 30 is an air suspension compressor 30, an air-liquid suspension compressor 30, a magnetic suspension compressor 30 or other centrifugal compressors 30.

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

Optionally, the heat exchange device 50 may be a plate heat exchanger, which has a long service life, better economic benefits and higher use reliability, and can provide stability for the water chilling unit.

Alternatively, the auxiliary cooling water inlet line 102 and the auxiliary freezing water inlet line 202 may be in winding contact with each other, and the heat exchange between the water in the auxiliary cooling water inlet line 102 and the water in the auxiliary freezing water inlet line 202 is realized 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 of 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 prolonged. By the arrangement, the water in the auxiliary cooling water inlet pipeline 102 and the water in the main cooling water inlet pipeline 101 flow into the cooling water inlet after being uniformly mixed, so that the water 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 in the auxiliary freezing water inlet pipeline 202 and the water in the main freezing water inlet pipeline 201 are mixed and then flow into the freezing water inlet.

The water flowing out of the water outlet of the auxiliary freezing water inlet pipeline 202 flows back to 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 in the auxiliary freezing water inlet pipeline 202 and the water in the main freezing water inlet pipeline 201 is prolonged. By the arrangement, the water in the auxiliary freezing water inlet pipeline 202 and the water in the main freezing water inlet pipeline 201 are uniformly mixed and then flow into the freezing water inlet, so that the water flowing into the freezing water pipe is prevented from being non-uniform.

In this embodiment, the auxiliary cooling water inlet line 102 and the auxiliary freezing water inlet line 202 can exchange heat, and on the one hand, can reduce the temperature of the cooling water, reduce the condensing pressure, increase the temperature of the freezing water, and then increase the pressure of the evaporator 20 in summer when the temperature of the freezing water is lower than the temperature of the cooling water, so that the pressure ratio between the condenser 10 and the evaporator 20 can be reduced. The reduced pressure ratio results in better compressor 30 unloading capacity, reduced surge risk, and increased compressor load at low loads, and better surge resistance. 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 a water chilling unit cannot be started and runs reversely after being started are solved. On the other hand, the flow rate of the cooling water is adjusted by the first and

second adjusting valves

1011 and 1021, and then the cooling water flows into the condenser 10, and the flow rate of the chilled water is adjusted by the third and

fourth adjusting valves

2011 and 2021, and then the cooling water flows into the evaporator 20, so that the condensing pressure of the condenser 10 is reduced in summer, and the pressure of the evaporator 20 is increased, thereby improving the effect of reducing the pressure ratio between the condenser 10 and the evaporator 20, and further improving the surge prevention effect.

With reference to fig. 2, the present embodiment further provides a method for controlling a water chilling unit, including:

s201, the water chilling unit obtains operation parameters of the water chilling unit.

S202, under the condition that the running parameters of the water chilling unit meet set conditions, the water chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to be opened, so that heat exchange is carried out between cooling water in the auxiliary cooling water inlet pipeline 102 and chilled water in the auxiliary freezing water inlet pipeline 202, and the water temperatures of a cooling water pipe and a chilled water pipe are regulated; the initial states of the second adjusting valve 1021 and the fourth adjusting valve 2021 are off.

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 pressures of the evaporator 20 and the condenser 10 can be adjusted simultaneously, the effect of reducing the pressure ratio of the water chilling unit is improved, and the surge is prevented better.

Optionally, the operating parameters of the chiller include: a pressure ratio r between the condenser 10 and the evaporator 20, a load of the compressor, a temperature of the chilled water, a temperature of the cooling water, and the like. The water chilling unit acquires the parameters through a sensor 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 parameter of the chiller, the second adjusting valve 1021 and the fourth adjusting 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 parameter of the chiller, and under the condition that the communication between the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 is controlled, the condensing pressure of the condenser 10 is reduced while the evaporating pressure of the evaporator 20 is increased, thereby increasing the effect of reducing the pressure ratio between the condenser 10 and the evaporator 20, and further increasing the surge prevention effect.

Alternatively, as shown in fig. 3, in the case that the operation parameter of the water chilling unit satisfies the set condition, the controlling, by the water chilling unit, the second regulating valve 1021 and the fourth regulating valve 2021 to be both opened includes:

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

S302, when the temperature of the cooling water is higher than that of the chilled water and r is more than r₁The chiller controls both the second adjustment valve 1021 and the fourth adjustment valve 2021 to open.

r is the pressure ratio between the condenser 10 and the evaporator 20, r₁Is a first pressure ratio threshold. If r > r₁If the pressure ratio is higher than the required unloading pressure ratio, the water chilling unit has the risk of stopping the machine if the pressure ratio is not reduced. Under this condition, control second governing valve 1021 and fourth governing valve 2021 and all open, because the temperature of assisting cooling inlet line 102 is lower, assist the water of cooling inlet line 102 and assist the water heat transfer of freezing inlet line 202 after, the temperature of assisting cooling inlet line 102 risees, the temperature of assisting freezing inlet line 202 reduces, and then reduce the inlet water temperature of cooling water inlet, can reduce the pressure of condenser 10, improve the temperature of freezing water inlet, the pressure of evaporimeter 20 has been improved, thereby reach the purpose of reducing the pressure ratio. If r is less than or equal to r₁In the case where the pressure ratio is within the normal range and the water chiller is not stopped without lowering the pressure ratio, the second regulating valve 1021 and/or the fourth regulating valve 2021 may be maintained in the current off state. The first pressure ratio threshold r is₁The determination can be made according to actual needs, and the present embodiment does not limit the present invention in any way.

In the present embodiment, the relationship between the pressure ratio between the condenser 10 and the evaporator 20 and the first threshold value is compared, and the second regulating valve 1021 and the fourth regulating valve 2021 are both controlled to be opened, thereby preventing the high pressure ratio of the chiller and improving the surge prevention effect.

Alternatively, as shown in fig. 4, in the case that the operation parameter of the water chilling unit satisfies the set condition, the controlling, by the water chilling unit, the second regulating valve 1021 and the fourth regulating valve 2021 to be both opened includes:

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

S402, when the temperature of the cooling water is higher than that of the chilled water and r is more than r₁Under the condition of (3), the water chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to be opened to a preset opening degree; wherein the preset opening degree is smaller than the maximum opening degree of the second adjusting valve 1021 and the fourth adjusting valve 2021.

At r > r₁The chiller controls the second and

fourth adjusting valves

1021, 2021 to open to a preset opening degree, thereby communicating the auxiliary cooling water inlet line 102 with the auxiliary freezing water inlet line 202. The second regulating valve 1021 and the fourth regulating valve 2021 are first opened to a preset opening degree, which is an initial opening degree of the second regulating valve 1021 and the fourth regulating valve 2021. The opening degrees of the second regulating valve 1021 and the fourth regulating valve 2021 are regulated to be at the preset opening degrees for a first preset duration to reduce the pressure ratio.

Optionally, with reference to fig. 5, in a case that the operation parameter of the water chilling unit satisfies the setting condition, the water chilling unit controls both the second regulating valve 1021 and the fourth regulating valve 2021 to be opened, including:

s501, the water chilling unit obtains a pressure ratio r between the condenser 10 and the evaporator 20, the temperature of cooling water and the temperature of chilled water.

S502, when the temperature of the cooling water is higher than that of the chilled water, and r is more than r₁Under the condition of (3), the water chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to be opened to a preset opening degree; wherein the preset opening degree is smaller than the maximum opening degree of the second adjusting valve 1021 and the fourth adjusting valve 2021.

S503 at r₂<r＜r₁In the case of (1), the water chilling unit 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 that the pressure ratio value r₃≤r≤r₂(ii) a Wherein r is₂Is a second pressure ratio threshold value, r₃Is the second pressure ratio threshold value and is,_r1＞r₂＞r₃。

at r > r₁The chiller controls the second and

fourth adjusting valves

1021, 2021 to open to a preset opening degree, thereby communicating the auxiliary cooling water inlet line 102 with the auxiliary freezing water inlet line 202. Second regulating valve1021 and the fourth regulating valve 2021 are first opened to a preset opening degree, which is the initial opening degree of the second regulating valve 1021 and the fourth regulating valve 2021. The opening degrees of the second regulating valve 1021 and the fourth regulating valve 2021 are regulated to be maintained at the preset opening degrees for a first preset time period so as to reduce the pressure ratio, and after the opening degrees of the second regulating valve 1021 and the fourth regulating valve 2021 are regulated to be maintained at the preset opening degrees for the first preset time period, at r₂<r＜r₁In the case of (1), the opening degrees of the second and

fourth regulating valves

1021, 2021 are increased, and the opening degrees of the first and

third regulating valves

1011, 2011 are decreased to adjust the pressure ratio r₃≤r≤r₂。r₂The second pressure ratio threshold is a target pressure ratio and is also an ideal pressure ratio for preventing surging. Second pressure ratio threshold r₂The first preset duration and the first preset opening degree can be determined according to actual needs, and the embodiment does not limit the duration, the first preset duration and the first preset opening degree.

In this embodiment, the second adjusting valve 1021 and the fourth adjusting valve 2021 are controlled to open to a preset opening degree, so that the cooling water of the auxiliary cooling water inlet pipeline 102 and the freezing water of the auxiliary freezing water inlet pipeline 202 exchange heat, and the pressure ratio is reduced preliminarily, but the reduction range is small, so that the running of the water chilling unit is prevented from generating large fluctuation. After a certain period of time, the opening degrees of the second regulating valve 1021 and the fourth regulating valve 2021 are increased, and/or the opening degrees of the first regulating valve 1011 and the third regulating valve 2011 are decreased, so that the pressure ratio r is kept at r₂Thereby reducing the pressure ratio to a desired pressure ratio to reduce the probability of surge of the compressor 30. After the auxiliary cooling water inlet line 102 and the auxiliary freezing water inlet line 202 are communicated, the opening degrees of the first adjusting valve 1011, the second adjusting valve 1021, the third adjusting valve 2011 and the fourth adjusting valve 2021 are controlled by a PID control algorithm, and the pressure ratio between the condenser 10 and the evaporator 20 is continuously monitored.

Optionally, with reference to fig. 6, an embodiment of the present disclosure provides another control method for a water chilling unit, including:

s601, the water chilling unit obtains a pressure ratio r between the condenser 10 and the evaporator 20, a temperature of the cooling water, and a temperature of the chilled water.

S602, at r<r₃In the case of (2), a water chillerThe group control second regulating valve 1021 and/or fourth regulating valve 2021 are opened.

When r < r₃When 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 of water in the main cooling water inlet pipeline 101 is increased, the water temperature of the cooling water pipe is improved, the flow of water in the main freezing water inlet pipeline 201 is increased, the water temperature of the freezing water pipe is reduced, and therefore the energy consumption of the water chilling unit is saved.

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

s701, the water chilling unit obtains a pressure ratio r between the condenser 10 and the evaporator 20, a temperature of the cooling water, and a temperature of the chilled water.

S702, when the temperature of the cooling water is higher than that of the chilled water and r is more than r₁The water chilling unit controls the second adjusting valve 1021 and the fourth adjusting valve 2021 to be opened to a preset opening degree.

S703 at r₂<r＜r₁In this case, the water chilling unit controls the second and

fourth regulating valves

1021, 2021 to increase the opening degree, and/or controls the first and

third regulating valves

1011, 2011 to decrease the opening degree so that the pressure ratio r becomes larger₃≤r≤r₂；

S704, in the process that the water chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to increase the opening degree and/or controls the first regulating valve 1011 and the third regulating valve 2011 to decrease the opening degree, when r is less than r₃Under the condition of (1), the water chilling unit controls the second regulating valve 1021 and/or the fourth regulating valve 2021 to be disconnected;

s705, after the water chilling unit executes S701, at r<Under the condition of r3, the water chilling unit maintains the current state; wherein r is₁Is a first pressure ratio threshold value, r₂Is a second pressure ratio threshold value, r₃Is a third pressure ratio threshold value, r₁＞r₂＞r₃。

A pressure ratio value r between the condensing pressure of the condenser 10 and the evaporating pressure of the evaporator 20 is obtained. At r > r₁The second and

fourth regulating valves

1021, 2021 are controlled to open. Second adjusting valve 1021 and fourth adjusting valveThe throttle valve 2021 is first opened to a predetermined opening degree, which is an initial opening degree of the second and

fourth regulating valves

1021, 2021. After the opening degrees of the second regulating valve 1021 and the fourth regulating valve 2021 are maintained at the preset opening degrees for the first preset time period, the opening degrees of the second regulating valve 1021 and the fourth regulating valve 2021 are continuously increased, and the opening degrees of the first regulating valve 1011 and the second regulating valve 1021 are decreased. Ideally, the pressure ratio r can be made r by adjusting the opening degrees of the first, second, third, and

fourth regulating valves

1011, 1021, 2011, and 2021 by a PID control algorithm₂. In this case, the opening of the regulating valve is adjusted so that the pressure ratio r is maintained at r₂And (4) finishing. In another case, in the process of adjusting the opening degree of the above-mentioned regulating valve, the pressure ratio r is lowered excessively, i.e., to less than r₃When, or, in order to keep the pressure ratio r at r₂In the process (2), the pressure ratio r still falls and is reduced to less than r₃In order to prevent the pressure ratio r from continuing to decrease, the second and

fourth regulating valves

1021, 2021 are controlled to be opened, and the decrease in the pressure ratio value is stopped. r is₂Is a second pressure ratio threshold value, r₃Is a third pressure ratio threshold value, r₁＞r₂＞r₃Here, r is₁The pressure ratio is a warning value of the pressure ratio, which is a value that the pressure ratio should at least reach in order to prevent surging of the compressor 30, and therefore, when the pressure ratio is decreased, the pressure ratio is decreased to r₂Enough ascending space is reserved for the pressure ratio value, the compressor 30 is kept not to generate surge for a long time as far as possible, and therefore the water chilling unit is kept to operate stably for a long time.

If r is less than or equal to r after the water chilling unit obtains the pressure ratio value r between the condenser 10 and the evaporator 20₁Indicating that the pressure ratio is within the safe range, the second regulating valve 1021 and the fourth regulating valve 2021 are controlled to continue to remain open without lowering the pressure ratio.

The second pressure ratio threshold r is₂A third pressure ratio threshold r₃And the first preset time length can be determined according to actual needs, and the embodiment does not limit the time lengths at all.

In the present embodiment, the first regulating valve 1011,The opening degrees of the second, third, and

fourth adjusting valves

1021, 2011, and 2021 can reduce the pressure ratio between the condenser 10 and the evaporator 20, thereby reducing the risk of surging of the compressor 30. When r < r₃At this time, the second regulating valve 1021 and the fourth regulating valve 2021 are controlled to close to prevent the pressure ratio from continuing to decrease.

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

In this embodiment, the water chilling unit obtains the parameters through a sensor, 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 chiller, the second adjusting valve 1021 and the fourth adjusting 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 chiller, and the temperature of the chilled water and the load of the compressor are increased under the condition that the communication between the auxiliary cooling water inlet pipeline 102 and the auxiliary freezing water inlet pipeline 202 is controlled, thereby improving the effect of preventing surging.

Alternatively, as shown in fig. 8, in the case that the operation parameter of the water chilling unit satisfies the set condition, controlling both the second regulating valve 1021 and the fourth regulating valve 2021 to be opened includes:

s801, the water chilling unit acquires the unloading capacity, the load of the compressor, the temperature of cooling water and the temperature of chilled water.

And S802, under the conditions that the temperature of the chilled water is lower than the temperature of the cooling water, the unloading capacity of the water chilling unit is minimum, the temperature of the chilled water is lower than the target temperature, the difference value 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 chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to be opened.

And acquiring the unloading capacity of the water chilling unit, the load of the compressor, the temperature of the cooling water and the temperature of the chilled water. When the unloading capacity of the chiller reaches a minimum, 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 has not yet reached the shutdown temperature difference, i.e., is less than the shutdown temperature difference, the compressor 30 is at risk of surging if a small load is still continuously applied to the compressor 30. In this case, the second and

fourth adjusting valves

1021 and 2021 are controlled to be opened, so that the temperature of the chilled water can be increased, the load of the compressor can be increased, and the risk of surging of the compressor 30 can be reduced. The unloading capacity of the water chilling unit reaches the minimum specifically: the compressor 30 is unloaded until the output capacity of the compressor 30 is the minimum, and the power, the rotation speed and the current of the compressor 30 can be considered as the minimum values under the corresponding working conditions, at which time, the output capacity of the compressor 30 can not be reduced any more.

It should be noted that the target temperature may be determined according to actual needs, and this embodiment does not limit it at all.

Optionally, with reference to fig. 9, the chiller controls both the second regulating valve 1021 and the fourth regulating valve 2021 to open, including:

and S901, the water chilling unit acquires the unloading capacity, the load of the compressor, the temperature of cooling water and the temperature of chilled water.

And S902, when the temperature of the chilled water is lower than the temperature of the cooling water, the unloading capacity of the water chilling unit is minimum, the temperature of the chilled water is lower than the target temperature, the difference value 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 chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to be opened to a preset opening degree.

And under the conditions that the unloading capacity of the water chilling unit is minimum, the temperature of the chilled water is lower than the target temperature, the difference value 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, controlling the second regulating valve 1021 and the fourth regulating valve 2021 to be opened. The second regulating valve 1021 and the fourth regulating valve 2021 are adjusted to be opened to a preset opening degree, which is an initial opening degree of the second regulating valve 1021 and the fourth regulating valve 2021. The opening degrees of the second and

fourth adjusting valves

1021 and 2021 are adjusted to a second preset opening degree for a second preset time period to increase the temperature of the chilled water and increase the load of the compressor.

Optionally, with reference to fig. 10, the chiller controls both the second regulating valve 1021 and the fourth regulating valve 2021 to open, including:

s1001, the water chilling unit obtains the unloading capacity, the load of the compressor, the temperature of cooling water and the temperature of chilled water.

And S1002, when the temperature of the chilled water is lower than the temperature of the cooling water, the unloading capacity of the water chilling unit is minimum, the temperature of the chilled water is lower than the target temperature, the difference value 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 chilling unit controls the second adjusting valve 1021 and the fourth adjusting valve 2021 to be opened to a preset opening degree.

S1003, when the temperature of the chilled water after the adjustment is lower than the target temperature, the water chiller controls the second adjusting valve 1021 and the fourth adjusting valve 2021 to increase the opening degree, and/or controls the first adjusting valve 1011 and the third adjusting valve 2011 to decrease the opening degree, so as to maintain the temperature of the chilled water at the target temperature and maintain the load of the compressor at the target load.

Under the condition that the unloading capacity of the water chilling unit is minimum, the temperature of the chilled water is lower than the target temperature, the difference value 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 regulating valve 1021 and the fourth regulating valve 2021 are controlled to be opened. The second regulating valve 1021 and the fourth regulating valve 2021 are adjusted to be opened to a second preset opening degree, which is the initial opening degree of the second regulating valve 1021 and the fourth regulating valve 2021. After the opening degrees of the second and

fourth adjusting valves

1021, 2021 are adjusted to the second preset opening degree for the second preset time period, the opening degrees of the second and

fourth adjusting valves

1021, 2021 are continuously adjusted to increase the temperature of the chilled water and the load of the compressor, and to maintain the temperature of the chilled water at the target temperature and the load of the compressor at the target load. It should be noted that the second preset time period, the target temperature and the target load may all be determined according to actual needs, and this embodiment does not limit them at all.

In this embodiment, the second adjusting valve 1021 and the fourth adjusting valve 2021 are first controlled to open 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 thus the temperature of the chilled water and the load of the compressor are initially increased, but the increase range is small, and the running of the water chiller is prevented from generating large fluctuation. After a period of time, the opening degrees of the second adjusting valve 1021 and the fourth adjusting valve 2021 are increased, and/or the opening degrees of the first adjusting valve 1011 and the third adjusting 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 chiller, including:

and under the conditions that the temperature of the chilled water is lower than the temperature of the cooling water, the unloading capacity of the water chilling unit is minimum, the temperature of the chilled water is lower than the target temperature, and the difference value between the temperature of the chilled water and the target temperature is smaller than the shutdown temperature difference, the water chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to be opened.

And under the condition that the temperature of the chilled water is higher than the target temperature and the load of the compressor is higher than the load threshold value, the water chilling unit controls the second regulating valve 1021 and/or the fourth regulating valve 2021 to be disconnected.

After the second adjusting valve 1021 and the fourth adjusting valve 2021 are opened, the opening degrees of the first adjusting valve 1011, the second adjusting valve 1021, the third adjusting valve 2011 and the fourth adjusting valve 2021 are controlled and adjusted by a PID control algorithm. The temperature of the chilled water and the load on the compressor continue to be 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 and

fourth regulating valves

1021, 2021 are closed.

Specifically, referring to fig. 11, the present embodiment provides another method for controlling a chiller, including:

s1101, the water chilling unit acquires the unloading capacity, the load of the compressor, the temperature of cooling water and the temperature of chilled water.

And S1102, under the conditions that the temperature of the chilled water is lower than the temperature of the cooling water, the unloading capacity of the water chilling unit is minimum, the temperature of the chilled water is lower than the target temperature, the difference value 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 chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to be opened to a preset opening degree.

S1103, when the adjusted temperature of the chilled water is lower than the target temperature, the chiller controls the second and

fourth adjusting valves

1021, 2021 to increase the opening degrees, and/or controls the first and

third adjusting valves

1011, 2011 to decrease the opening degrees, so as to maintain the temperature of the chilled water at the target temperature and the load of the compressor at the target load.

And S1104, in the process that the water chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to increase the opening degrees and/or controls the first regulating valve 1011 and the third regulating valve 2011 to decrease the opening degrees, the water chilling unit controls the second regulating valve 1021 and/or the fourth regulating valve 2021 to be disconnected under the conditions that the temperature of the chilled water is higher than the target temperature and the load of the compressor is higher than a load threshold value.

S1105, after the chiller executes S1101, the chiller maintains the current state 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.

And acquiring the unloading capacity of the water chilling unit, the load of the compressor, the temperature of the cooling water and the temperature of the chilled water. And under the conditions that the temperature of the chilled water is lower than the temperature of the cooling water, the load of the compressor is lower than or equal to the load threshold value, the temperature of the chilled water is lower than the target temperature, and the difference value between the temperature of the chilled water and the target temperature is smaller than the shutdown temperature difference, controlling the second regulating valve 1021 and the fourth regulating valve 2021 to be opened. Otherwise, the second regulating valve 1021 and the fourth regulating valve 2021 are controlled to remain open, that is, the second regulating valve 1021 and the fourth regulating valve 2021 are controlled to remain closed. After the second regulating valve 1021 and the fourth regulating valve 2021 are opened, the second regulating valve 1021 and the fourth regulating valve 2021 are opened to a preset opening degree, which is an initial opening degree of the regulating valves. After the opening degrees of the second adjusting valve 1021 and the fourth adjusting valve 2021 are maintained at the preset opening degrees for a second preset time period, the opening degrees of the second adjusting valve 1021 and the fourth adjusting valve 2021 are continuously adjusted, so that the temperature of the chilled water and the load of the compressor are increased. Ideally, the opening degrees of the first, second, third, and

fourth adjusting valves

1011, 1021, 2011, and 2021 are adjusted by a PID control algorithm, so that the temperature of the chilled water can be brought to the target temperature, and the load on the compressor can be brought to the target load. In this case, the opening degrees of the first, second, third, and

fourth adjusting valves

1011, 1021, 2011, and 2021 may be adjusted to maintain the temperature of the chilled water at the target temperature and the load on the compressor at the target load. In another case, the temperature of the chilled water is increased excessively and exceeds the target temperature during the adjustment of the opening degree of the adjusting valve, or the temperature of the chilled water is still increased during the maintenance of the temperature of the chilled water at the target temperature. In this case, and when the load of the compressor is greater than the load threshold, in order to prevent the temperature of the chilled water from continuing to increase, the second regulating valve 1021 and/or the fourth regulating valve 2021 are controlled to be turned off, that is, the second regulating valve 1021 and the fourth regulating 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 a 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, and this embodiment does not limit them at all.

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

fourth adjusting valves

1011, 1021, 2011, and 2022 are controlled to increase the temperature of the chilled water and the load on the compressor, thereby reducing the risk of surging of the compressor 30. After the temperature of the chilled water and the load of the compressor reach a safe range, the valve is adjusted in time, and certain energy can be saved.

Optionally, with reference to fig. 12, in a case that the operation parameter of the water chilling unit satisfies the setting condition, controlling both the second regulating valve 1021 and the fourth regulating valve 2021 to be opened includes:

s1201, the water chilling unit obtains the temperature of cooling water and the temperature of chilled water.

S1202, when the temperature of the cooling water is lower than the temperature of the chilled water and the water chilling unit is started and the temperature of the cooling water is lower than the temperature threshold, the water chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to be both opened, and controls the first regulating valve 1011 and the third regulating valve 2011 to be both opened.

The temperature of the cooling water and the temperature of the chilled water are obtained. In winter, when the temperature of cooling water is about 0 ℃, some factories need to use a water chilling unit to cool equipment. Under the condition, when the water chilling unit is started, the pressure of the water chilling unit is low due to the low temperature of cooling water, and the water chilling unit cannot be started, or runs reversely after being started, so that the cooling medium of the compressor 30 is not cooled. Therefore, when the water chilling unit is started, if the temperature of the cooling water is lower than the temperature threshold, the second adjusting valve 1021 and the fourth adjusting valve 2021 are controlled to be both opened, and the first adjusting valve 1011 and the third adjusting valve 2011 are controlled to be both opened, so that the water of the auxiliary cooling water inlet pipeline 102 and the water of the auxiliary freezing water inlet pipeline 202 exchange heat, and the water temperature of the cooling water inlet is increased. In practical applications, 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 runs reversely after being started are solved. And after the water chilling unit is started successfully, continuously monitoring the temperature of the cooling water and the temperature of the chilled water. When the temperature of the cooling water is higher than that of the chilled water, the water chiller will not reverse, and therefore the second adjusting valve 1021 and the fourth adjusting valve 2021 are controlled to be both off, and the first adjusting valve 1011 and the third adjusting valve 2011 are controlled to be both on.

Specifically, with reference to fig. 13, the present embodiment provides another method for controlling a water chilling unit, including:

and S1301, the water chilling unit acquires the temperature of cooling water and the temperature of chilled water.

S1302, when the temperature of the cooling water is lower than the temperature of the chilled water and the water chilling unit is started and the temperature of the cooling water is lower than the temperature threshold, the water chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to be opened, and controls the first regulating valve 1011 and the third regulating valve 2011 to be turned off.

S1303, after the water chilling unit is started, if the temperature of the cooling water is greater than the temperature threshold, the water chilling unit controls the second regulating valve 1021 and the fourth regulating valve 2021 to be both turned off, and controls the first regulating valve 1011 and the third regulating valve 2011 to be both turned on.

If the temperature of the cooling water is greater than or equal to the temperature threshold when the water chilling unit is started, the water chilling unit controls the second adjusting valve 1021 and the fourth adjusting valve 2021 to be both switched off, and controls the first adjusting valve 1011 and the third adjusting valve 2011 to be both switched on, so that the energy consumption of the water chilling unit is saved.

In this embodiment, when the water chilling unit is started, if the temperature of the cooling water is lower than the temperature threshold, the second regulating valve 1021 and the fourth regulating valve 2021 are controlled to be opened, so that the second regulating valve 1021 and the fourth regulating valve 2021 are both opened, 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 runs reversely after being started are solved. After the water chilling unit is started successfully, if the temperature of the cooling water is higher than that of the chilled water, the second adjusting valve 1021 and the fourth adjusting valve 2021 are controlled to be closed, so that energy is saved.

Referring to fig. 12, the present embodiment provides an apparatus for controlling a water chilling unit, which includes an obtaining module and a control module. The acquisition module is configured to acquire the operating parameters of the water chilling unit; the control module is configured to control the second and

fourth regulating valves

1021, 2021 to open according to the operating parameters of the chiller; the initial states of the second adjusting valve 1021 and the fourth adjusting valve 2021 are off.

Adopt the device for controlling cooling water set that this embodiment provided, can be according to the parameter of cooling water set, control second governing valve 1021 and fourth governing valve 2021 are opened, thereby make the parameter that assists cooling water inlet pipe 102 and assist the break-make of freezing water inlet pipe 202 and match the cooling water set, and under the circumstances that cooling water inlet pipe 102 and the supplementary freezing water inlet pipe 202 intercommunication are assisted in the control, can also improve the evaporating pressure of evaporimeter 20 when reducing the condensing pressure of condenser 10, thereby improve the effect that reduces the pressure ratio between condenser 10 and evaporimeter 20, and then improve the effect of prevention surge.

As shown in 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 902 and a bus 903. The processor 90, the communication interface 902 and the memory 901 can communicate with each other via the bus 903. Communication interface 902 may be used for the transfer of information. The processor 90 may call logic instructions in the memory 901 to perform the method for controlling a chiller, of the above-described embodiment.

In addition, the logic instructions in the memory 901 may be implemented in the form of software functional units and stored in a computer readable storage medium when the logic instructions are sold or used as independent products.

The memory 901 is used as a computer readable storage medium for storing software programs, computer executable programs, such as program instructions/modules corresponding to the methods in the embodiment. The processor 90 executes functional applications and data processing by executing program instructions/modules stored in the memory 901, namely, implements the method for controlling the 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, an application program required for at least one function; the storage data area may store data created according to the use of the terminal device, and the like. Further, the memory 901 may include a high-speed random access memory 901, and may also include a nonvolatile memory 901.

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

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

The above description and drawings sufficiently illustrate embodiments of the disclosure to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. The examples merely typify 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. Furthermore, the words used in the specification are words of description only and are not intended to limit the claims. As used in the description of the embodiments and the claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Furthermore, the terms "comprises" and/or "comprising," when used in this application, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Without further limitation, an element defined by the phrase "comprising an …" does not exclude the presence of other like elements in a process, method or apparatus that comprises the element. In this document, each embodiment may be described with emphasis on differences from other embodiments, and the same and similar parts between the respective embodiments may be referred to each other. For methods, products, etc. of the embodiment disclosures, reference may be made to the description of the method section for relevance if it corresponds to the method section of the embodiment disclosure.

Those of skill in the art would 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 may depend upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the disclosed embodiments. It can be clearly understood by the skilled person that, for convenience and brevity of description, the specific working processes of the system, the apparatus and the unit described above may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the embodiments disclosed herein, the disclosed methods, products (including but not limited to devices, apparatuses, etc.) may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units may be merely a logical division, and in actual implementation, there may be another division, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form. The units described as separate parts may or may not be physically separate, and parts displayed 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 can be selected according to actual needs to implement the present embodiment. In addition, functional units in the embodiments of the present disclosure may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

The flowchart 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 disclosed in the description, and sometimes there is no specific order between the different operations or steps. For example, two sequential operations or steps may in fact be executed substantially concurrently, or they may sometimes be executed in the reverse order, depending upon the functionality involved. Each block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, can be implemented by special purpose hardware-based systems that 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 a cooling water pipe, and the evaporator exchanges heat through a freezing 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 connected with the auxiliary freezing water inlet pipeline; the method comprises the following steps:

acquiring the operating parameters of the water chilling unit;

under the condition that the operating parameters of the water chilling unit meet set conditions, controlling the second regulating valve and the fourth regulating valve to be opened so that cooling water in the auxiliary cooling water inlet pipeline and chilled water in the auxiliary freezing water inlet pipeline exchange heat to regulate the water temperatures of the cooling water pipe and the chilled water pipe;

wherein the second and fourth regulator valves are initially open.

2. The method of claim 1, wherein the operating parameters of the chiller include a pressure ratio r between the condenser and the evaporator, a temperature of chilled water, and a temperature of cooling water.

3. The method of claim 2, wherein the operating parameters of the chiller satisfy set conditions, comprising:

the temperature of the cooling water is higher than that of the chilled water, and r is more than r₁；

Wherein r is₁Is a first pressure ratio threshold.

4. The method of claim 3, wherein the controlling the second and fourth regulator valves to both open comprises:

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

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

5. The method of claim 4, wherein the main cooling water inlet line is provided with a first regulating valve, the main freezing water inlet line is provided with a third regulating valve, and after controlling the second regulating valve and the fourth regulating valve to be opened to a preset opening degree, the method further comprises:

at r₂<r＜r₁In the case of (1), the second and fourth regulating valves are controlled to increase the opening degree, and/or the first and third regulating valves are controlled to decrease the opening degree so that the pressure ratio r becomes the pressure ratio r₃≤r≤r₂；

Wherein r is₂Is a second pressure ratio threshold value, r₃Is a three pressure ratio threshold, r₁＞r₂＞r₃。

6. The method of claim 5, further comprising:

at r < r₃In the case of (2), the second and/or fourth regulating valve is/are controlled to be opened.

7. The method of claim 1, wherein the operating parameters of the chiller include an unloading capacity of the chiller, a load of the compressor, a temperature of the cooling water, and a temperature of the chilled water.

8. The method of claim 7, wherein the operating parameters of the chiller satisfy set conditions, comprising:

the temperature of the cooling water is higher than that of the chilled water, the unloading capacity of the water chilling unit is the minimum, the temperature of the chilled water is lower than the target temperature, the difference value 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.

9. The method of claim 8, wherein controlling both the second and fourth regulator valves to open comprises:

10. The method of claim 9, wherein the main cooling water inlet line is provided with a first regulating valve, the main freezing water inlet line is provided with a third regulating valve, and after controlling the second regulating valve and the fourth regulating valve to be opened to a preset opening degree, the method further comprises:

and under the condition that the temperature of the chilled water after regulation is still lower than the target temperature, 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, 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.

11. The method of any one of claims 7 to 10, further comprising:

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

12. The method of claim 1, wherein the main cooling water inlet line is provided with a first regulating valve, the main chilling water inlet line is provided with a third regulating valve, the method further comprising:

when the temperature of the cooling water is lower than that of the chilled water and the water chilling unit is started, the second regulating valve and the fourth regulating valve are controlled to be opened and the first regulating valve and the third regulating valve are controlled to be opened under the condition that the temperature of the cooling water is lower than a temperature threshold value.

13. The method of claim 12,

after controlling the second regulating valve and the fourth regulating valve to be opened and controlling the first regulating valve and the third regulating valve to be disconnected, the method further comprises the following steps:

and after the water chilling unit is started, controlling the second regulating valve and the fourth regulating valve to be both switched off and controlling the first regulating valve and the third regulating valve to be both switched on under the condition that the temperature of the cooling water is higher than that of the chilled water.

14. An apparatus for controlling a chiller comprising a processor and a memory storing program instructions, characterized in that the processor is configured to execute the method for controlling a chiller according to any of claims 1 to 13 when executing the program instructions.

15. A water chilling unit comprises a compressor, a condenser, a throttling device and a condenser which are connected in sequence; the condenser exchanges heat through a cooling water pipe, and the evaporator exchanges heat through a freezing 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 in contact with 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 to adjust the water temperatures of the cooling water pipe and the freezing water pipe.

16. The water chilling unit of claim 15, further comprising:

the apparatus for controlling a chiller according to claim 14 wherein said second regulating valve and said fourth regulating valve are both electrically connected to said apparatus for controlling a chiller.

17. The chiller according to claim 15 or 16, further comprising:

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

18. The water chilling unit of claim 16, 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;

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