CN115355640A - Method and device for controlling water chilling unit, water chilling unit and storage medium - Google Patents

Method and device for controlling water chilling unit, water chilling unit and storage medium Download PDF

Info

Publication number
CN115355640A
CN115355640A CN202211034760.5A CN202211034760A CN115355640A CN 115355640 A CN115355640 A CN 115355640A CN 202211034760 A CN202211034760 A CN 202211034760A CN 115355640 A CN115355640 A CN 115355640A
Authority
CN
China
Prior art keywords
rotating speed
compressor
pressure difference
water temperature
control quantity
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN202211034760.5A
Other languages
Chinese (zh)
Other versions
CN115355640B (en
Inventor
任文臣
张志平
张捷
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Qingdao Haier Central Air Conditioner Co Ltd
Original Assignee
Qingdao Haier Central Air Conditioner Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Qingdao Haier Central Air Conditioner Co Ltd filed Critical Qingdao Haier Central Air Conditioner Co Ltd
Priority to CN202211034760.5A priority Critical patent/CN115355640B/en
Publication of CN115355640A publication Critical patent/CN115355640A/en
Application granted granted Critical
Publication of CN115355640B publication Critical patent/CN115355640B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/40—Fluid line arrangements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B49/00—Arrangement or mounting of control or safety devices
    • F25B49/02—Arrangement or mounting of control or safety devices for compression type machines, plants or systems
    • F25B49/022—Compressor control arrangements
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2600/00—Control issues
    • F25B2600/02—Compressor control
    • F25B2600/021—Inverters therefor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B2600/00—Control issues
    • F25B2600/02—Compressor control
    • F25B2600/025—Compressor control by controlling speed
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
    • Y02B30/70—Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Mechanical Engineering (AREA)
  • Thermal Sciences (AREA)
  • General Engineering & Computer Science (AREA)
  • Devices That Are Associated With Refrigeration Equipment (AREA)

Abstract

The application relates to the technical field of refrigeration, and discloses a method for controlling a water chilling unit, which comprises the following steps: acquiring the frequency loading and unloading control quantity of the rotating speed of the compressor; acquiring the pressure difference fluctuation control quantity of the rotating speed of the compressor; and regulating the rotating speed of the compressor according to the frequency loading and unloading control quantity and the pressure difference fluctuation control quantity. According to the method and the device, the frequency is controlled through the frequency converter, and the hysteresis quality existing in the control is considered, so that the subsequent adjusting process of the rotating speed of the motor of the compressor is optimized. Meanwhile, the influence of the frequency change of the compressor on the oil return performance of the water chilling unit is considered, and the corresponding control quantity is introduced by monitoring the fluctuation condition of the pressure difference of suction and discharge of the compressor, so that the rotating speed of the compressor can be adjusted more accurately, and the stable operation of the water chilling unit is facilitated. The application also discloses a device for controlling the water chilling unit, the water chilling unit and a storage medium.

Description

Method and device for controlling water chilling unit, water chilling unit and storage medium
Technical Field
The present application relates to the field of refrigeration technologies, and for example, to a method and an apparatus for controlling a chiller, and a storage medium.
Background
At present, a water chilling unit generally judges the specific load condition by calculating the change of water temperature and controls a compressor by adopting a variable frequency speed regulation method, thereby realizing the continuous regulation of cold quantity. And the produced cold energy is transferred to the water body, so that the water temperature is always kept near the expected value.
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 related technology has higher requirement on the control precision of frequency conversion speed regulation. If the adjustment of the rotational speed of the compressor is controlled only by a simple frequency-up-down operation, the water temperature may be excessively adjusted due to the hysteresis of the water temperature change. And further cause frequent frequency increase and decrease of the compressor, which is not beneficial to the stable operation of the water chilling unit. Meanwhile, the frequency conversion control of the compressor can also influence the oil return effect of the unit. The frequent frequency increase and decrease phenomenon of the compressor can further cause the oil leakage phenomenon of the compressor, and the running stability of the water chilling unit is seriously influenced.
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, the water chilling unit and a storage medium, which can enable the adjustment of the rotating speed of a compressor to be more accurate and are beneficial to the stable operation of the water chilling unit.
In some embodiments, the method comprises:
acquiring the frequency loading and unloading control quantity of the rotating speed of the compressor;
acquiring the pressure difference fluctuation control quantity of the rotating speed of the compressor;
and regulating the rotating speed of the compressor according to the frequency loading and unloading control quantity and the pressure difference fluctuation control quantity.
In some embodiments, the apparatus includes a processor and a memory storing program instructions, the processor being configured to execute the above-described method for controlling a chiller when executing the program instructions.
In some embodiments, the chiller includes the above-described apparatus for controlling a chiller.
In some embodiments, the storage medium stores program instructions that, when executed, perform the method for controlling a chiller as described above.
The method and the device for controlling the water chilling unit, the water chilling unit and the storage medium provided by the embodiment of the disclosure can realize the following technical effects:
in the embodiment of the disclosure, the frequency is controlled by the frequency converter, and the hysteresis of the control is considered, so that the subsequent process of adjusting the rotating speed of the motor of the compressor is optimized. Meanwhile, the embodiment of the disclosure also considers the influence of the frequency variation of the compressor on the oil return performance of the unit, and introduces the corresponding control quantity by monitoring the fluctuation condition of the pressure difference of suction and discharge of the compressor, thereby enabling the adjustment of the rotating speed of the compressor to be more accurate and being beneficial to the stable operation of the water chilling unit.
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 in the accompanying drawings, which correspond to the accompanying drawings and not in a limiting sense, in which elements having the same reference numeral designations represent like elements, and in which:
FIG. 1 is a schematic diagram of a method for controlling a chiller according to an embodiment of the present disclosure;
FIG. 2 is a schematic diagram of another method for controlling a chiller according to an embodiment of the present disclosure;
FIG. 3 is a schematic diagram of another method for controlling a chiller according to an embodiment of the present disclosure;
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 is a schematic diagram of an apparatus for controlling a chiller according to an embodiment of the present disclosure.
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.
The term "plurality" means two or more, unless otherwise specified.
In the embodiment of the present disclosure, the character "/" indicates that the preceding and following objects are in an or relationship. For example, A/B represents: a or B.
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.
The term "correspond" may refer to an association or binding relationship, and a corresponds to B refers to an association or binding relationship between a and B.
At present, a water chilling unit generally judges the specific load condition by calculating the change of water temperature and controls a compressor by adopting a variable frequency speed regulation method, thereby realizing the continuous regulation of refrigeration capacity. And the produced cold energy is transferred to the water body, so that the water temperature is always kept near the expected value.
But the related technology has higher requirement on the control precision of variable frequency speed regulation. If the adjustment of the rotational speed of the compressor is controlled only by a simple frequency-up-down operation, the water temperature may be excessively adjusted due to the hysteresis of the water temperature change. And further cause frequent frequency increase and decrease of the compressor, which is not beneficial to the stable operation of the water chilling unit. Meanwhile, the frequency conversion control of the compressor can also influence the oil return effect of the unit. The frequent frequency increase and decrease phenomenon of the compressor may further cause the oil leakage phenomenon of the compressor, and seriously affects the stability of the running of the water chilling unit.
Referring to fig. 1, an embodiment of the present disclosure provides a method for controlling a chiller, including:
s101, the processor obtains the frequency loading and unloading control quantity of the rotating speed of the compressor.
S102, the processor obtains the pressure difference fluctuation control quantity of the rotating speed of the compressor.
And S103, the processor adjusts the rotating speed of the compressor according to the frequency load and unload control quantity and the pressure difference fluctuation control quantity.
By adopting the method for controlling the water chilling unit, provided by the embodiment of the disclosure, the frequency is controlled by the frequency converter, and the hysteresis of the control is considered, so that the subsequent regulation process of the rotating speed of the motor of the compressor is optimized. Meanwhile, the embodiment of the disclosure also considers the influence of the frequency variation of the compressor on the oil return performance of the chiller, and introduces corresponding control quantity by monitoring the fluctuation condition of the suction and discharge air pressure difference of the compressor, so that the adjustment of the rotating speed of the compressor can be more accurate, and the steady operation of the chiller is facilitated.
Optionally, as shown in fig. 2, the processor obtains the frequency loading/unloading control amount of the compressor rotation speed, and includes:
s201, the processor acquires a PID adjusting value of the rotating speed of the compressor corresponding to the frequency fluctuation amount.
S202, the processor determines the load and unload coefficients.
S203, the processor determines the frequency load and unload control quantity of the rotating speed of the compressor according to the PID regulating value and the load and unload coefficient.
Therefore, the frequency adjusting signal of the frequency converter can be received, and the PID algorithm is utilized to further optimize the subsequent adjusting process of the rotating speed of the motor of the compressor. Meanwhile, by introducing the load increasing and reducing coefficient, the control quantity can be reasonably corrected by combining the current working condition so as to avoid the over-regulation of the rotating speed of the compressor. Thereby facilitating more precise control of the temperature of the water to be maintained near the desired value.
Optionally, the processor obtains a PID adjustment value of the compressor rotation speed corresponding to the frequency fluctuation amount, including: the processor determines the frequency variation amount; the processor determines a PID adjustment value of the compressor rotation speed corresponding to the frequency fluctuation amount according to an incremental PID algorithm. Therefore, the embodiment of the disclosure can accurately control the adjusting process of the rotating speed of the compressor while adjusting the running frequency of the compressor, so as to avoid the condition of over-adjusting the rotating speed. Therefore, the running frequency of the compressor can be adapted to the rotating speed, and the water temperature can be controlled to be kept close to the expected value more accurately.
Optionally, the processor determining the amount of frequency variation comprises: the processor receives the adjusting signal of the frequency converter and analyzes the adjusting signal to obtain the frequency variation. Therefore, according to the working condition of the frequency converter, the method and the device can simply obtain the adjustment quantity of the running frequency of the compressor, so that the subsequent adjustment process of the rotating speed of the motor of the compressor can be reasonably controlled.
Optionally, the processor determines the amount of frequency variation, comprising: the processor acquires the current water temperature and determines the set water temperature; the processor determines the target refrigerating capacity of the water chilling unit according to the current water temperature and the set water temperature; the processor determines the frequency variation amount according to the target refrigerating capacity. Therefore, the embodiment of the disclosure can determine the refrigerating capacity of the water chilling unit by detecting the current water temperature, further judge the load condition of the unit, and reasonably control the running frequency of the compressor to adjust. Therefore, the embodiment of the disclosure can properly predict the frequency variation amount by combining the current water temperature, so that the adjusting process of the rotating speed of the compressor can be controlled more quickly. Which facilitates more precise control of the water temperature to be maintained around a desired value.
Optionally, the processor determines the target cooling capacity of the chiller according to the current water temperature and the set water temperature, and includes: processor computing Q 1 ＝C p ×ρ×L×|T 1 -T s Obtaining the target refrigerating capacity Q of the water chilling unit 1 . Wherein, C p Is the specific heat of water, ρ is the density of water, L is the flow rate of water, T 1 Is the current water temperature, T s To set the water temperature. In this way, embodiments of the present disclosure may determine the cooling capacity of a chiller in conjunction with a heat calculation formula. And then can rationally judge the load condition of cooling water set to more accurately control compressor operating frequency and adjust.
Optionally, the value range of the add/subtract load coefficient is [0, 10]. The load increasing and reducing coefficients can be selected according to the specific working conditions of the water chilling unit so as to more accurately adjust the rotating speed of the compressor. Specifically, the value of the load addition and subtraction coefficient may be any value such as 0.5, 1 or 1.5.
Optionally, the processor determines the add-subtract load factor, including: the processor obtains the current water temperature; the processor determines the average rotating speed of the compressor in the load increasing and reducing period; and the processor determines the load increasing and reducing coefficient according to the current water temperature and the average rotating speed. Therefore, the embodiment of the disclosure can identify the current working condition according to the current water temperature and the average rotating speed of the compressor in the load increasing and reducing period, and then can select a proper load increasing and reducing coefficient to correct the control quantity so as to avoid the over-regulation of the rotating speed of the compressor. Thereby facilitating more precise control of the temperature of the water to be maintained near the desired value.
Optionally, the processor determines the load increase and decrease coefficient according to the current water temperature and the average rotation speed, and includes: under the condition that the current water temperature is greater than or equal to the set water temperature and the average rotating speed is greater than the preset rotating speed, the processor determines the load increasing and reducing coefficient as a first load increasing and reducing coefficient; or the processor determines the load increase and decrease coefficient as a second load increase and decrease coefficient under the condition that the current water temperature is greater than or equal to the set water temperature and the average rotating speed is less than or equal to the preset rotating speed; or under the condition that the current water temperature is less than the set water temperature and the average rotating speed is greater than the preset rotating speed, the processor determines the load increasing and reducing coefficient as a third load increasing and reducing coefficient; or, under the condition that the current water temperature is less than the set water temperature and the average rotating speed is less than or equal to the preset rotating speed, the processor determines that the load increase and load decrease coefficient is the fourth load increase and decrease coefficient. Therefore, the embodiment of the disclosure can identify the current working condition according to the current water temperature and the average rotating speed of the compressor in the load increasing and reducing period, and then can select a proper load increasing and reducing coefficient to correct the control quantity so as to avoid the over-regulation of the rotating speed of the compressor. Thereby facilitating more precise control of the water temperature to be maintained around the desired value.
Optionally, the processor determines the frequency loading and unloading control quantity of the compressor rotation speed according to the PID adjustment value and the loading and unloading coefficient, and the method includes: and the processor multiplies the PID regulating value by the load increasing and reducing coefficient to obtain the frequency load reducing control quantity of the rotating speed of the compressor. In this way, through the control of the frequency converter to the frequency, and in consideration of the hysteresis quality existing in the control, the disclosed embodiment can further optimize the subsequent adjustment process to the rotating speed of the compressor motor. Therefore, the regulation of the rotating speed of the compressor is more accurate, and the water temperature can be controlled to be kept near the expected value more accurately.
Optionally, as shown in fig. 3, the determining, by the processor, the add/subtract load coefficient includes:
s301, the processor obtains the current water temperature.
S302, the processor determines the average rotating speed of the compressor in the load and unload period.
S303, when the current water temperature is greater than or equal to the set water temperature and the average rotating speed is greater than the preset rotating speed, the processor determines the load increasing and reducing coefficient to be a first load increasing and reducing coefficient.
S304, when the current water temperature is larger than or equal to the set water temperature and the average rotating speed is smaller than or equal to the preset rotating speed, the processor determines the load increasing and reducing coefficient to be a second load increasing and reducing coefficient.
S305, when the current water temperature is lower than the set water temperature and the average rotating speed is higher than the preset rotating speed, the processor determines the load increasing and reducing coefficient to be a third load increasing and reducing coefficient.
S306, under the condition that the current water temperature is smaller than the set water temperature and the average rotating speed is smaller than or equal to the preset rotating speed, the processor determines that the load and unload coefficient is a fourth load and unload coefficient.
Therefore, the embodiment of the disclosure can identify the current working condition according to the current water temperature and the average rotating speed of the compressor in the load increasing and reducing period, and then can select a proper load increasing and reducing coefficient to correct the control quantity so as to avoid the over-regulation of the rotating speed of the compressor. Thereby facilitating more precise control of the water temperature to be maintained around the desired value.
Optionally, the duration of the add/subtract duty cycle is in a range of [1s,30s ]. The duration of the load increasing and load reducing period can be selected according to the specific working condition of the water chilling unit so as to more accurately obtain the actual rotating speed of the compressor. Preferably, the duration of the add-subtract load cycle may be set to 5s.
Specifically, the first load reduction coefficient is smaller than the second load reduction coefficient. Therefore, when the current water temperature is larger than or equal to the set water temperature, the unit is indicated to enter the loading working condition, and the average rotating speed of the compressor in the load increasing and load reducing period is further identified. If the average rotating speed is larger, a first load and unload coefficient which is slightly smaller is selected to properly reduce the increase of the rotating speed. Otherwise, if the average rotating speed is smaller, a second load-reducing coefficient which is slightly larger is selected to increase the amplitude of the rotating speed properly. Therefore, the rotating speed of the motor of the compressor can be adjusted more accurately, and the water temperature can be controlled to be maintained near the expected value more accurately.
Specifically, in some embodiments, after being verified by multiple experimental tests, the first loading and unloading coefficient may be set to 0.6, and the second loading and unloading coefficient may be set to 1.0.
Specifically, the third loading and unloading coefficient is larger than the fourth loading and unloading coefficient. Therefore, when the current water temperature is smaller than the set water temperature, the unit is indicated to enter the load shedding working condition, and the average rotating speed of the compressor in the load shedding period is further identified. If the average rotating speed is larger, a third slightly larger load-reducing coefficient is selected to properly increase the reduction amplitude of the rotating speed. Otherwise, if the average rotating speed is smaller, a fourth slightly smaller load-reducing coefficient is selected to properly reduce the amplitude of the rotating speed. Therefore, the rotating speed of the motor of the compressor can be adjusted more accurately, and the water temperature can be controlled to be maintained near the expected value more accurately.
Specifically, in some embodiments, after being verified by multiple experimental tests, the third loading and unloading coefficient may be set to 0.8, and the second loading and unloading coefficient may be set to 0.6.
Alternatively, as shown in fig. 4, the processor obtains the pressure difference fluctuation control amount of the compressor rotation speed, and includes:
s401, the processor obtains the pressure difference change rate in a set time period.
S402, the processor determines a pressure difference influence coefficient.
And S403, the processor determines the pressure difference fluctuation control quantity of the rotating speed of the compressor according to the pressure difference change rate and the pressure difference influence coefficient.
Thus, according to the embodiment of the disclosure, by monitoring the differential pressure change rate in the set time period, the influence of the frequency change of the compressor on the oil return performance of the unit can be considered. Through monitoring compressor suction and exhaust differential pressure's undulant condition to introduce corresponding controlled quantity, this disclosed embodiment can make the regulation of compressor rotational speed more accurate, thereby can avoid excessively adjusting to cause the compressor oil leakage phenomenon to appear, is favorable to the steady operation of cooling water set.
Optionally, the processor obtains a rate of change of the differential pressure over a set period of time, including: the processor continuously monitors the suction pressure and the exhaust pressure of the compressor, and calculates the difference value between the suction pressure and the exhaust pressure to obtain a real-time pressure difference; the processor determines a first real-time pressure difference at the starting point of a set time period and a second real-time pressure difference at the end point of the set time period; and the processor acquires the pressure difference change rate in a set time period according to the first real-time pressure difference and the second real-time pressure difference. Therefore, the embodiment of the disclosure continuously monitors the difference value between the suction pressure and the exhaust pressure, namely the real-time pressure difference, and further obtains the change condition of the real-time pressure difference within a set time period, so that the fluctuation condition of the oil return performance of the unit can be accurately judged.
Optionally, the duration of the set period is set to a value in a range of [1s,60s ]. The duration of the set time period can be selected according to the specific working condition of the water chilling unit so as to more accurately acquire the change condition of the suction and exhaust pressure difference of the compressor. Preferably, the duration of the set period may be set to 10s. Meanwhile, the set period end corresponds to a time node at which the current water temperature is acquired. Therefore, the consistency of regulating and controlling the frequency load and unload control quantity and the pressure difference fluctuation control quantity can be improved.
Optionally, the processor obtains a differential pressure change rate within a set time period according to the first real-time differential pressure and the second real-time differential pressure, and includes: the processor subtracts the first real-time pressure difference from the second real-time pressure difference to obtain a pressure difference value; the processor divides the differential pressure difference by the duration of the set time period to obtain the differential pressure change rate in the set time period. Therefore, the embodiment of the disclosure can monitor the change condition of the suction and exhaust pressure difference before and after the set time period, and properly adjust the rotating speed of the compressor by utilizing the calculated pressure difference change rate, so that the oil return performance of the unit does not fluctuate greatly. Thereby can avoid the compressor to appear the oil leakage phenomenon, be favorable to the steady operation of cooling water set.
Specifically, when the differential pressure change rate is a positive value, it indicates that the suction and exhaust differential pressure is gradually reduced in a set period of time, and at this time, the oil return performance of the unit is deteriorated. Through introducing the pressure difference fluctuation control quantity, and this control quantity is also positive value corresponding to the pressure difference rate of change, this disclosed embodiment can suitably increase compressor rotational speed to can promote the oil return effect of unit, be favorable to the steady operation of cooling water set. On the contrary, when the pressure difference change rate is a negative value, the pressure difference of the air suction and exhaust in the set time period is shown to be gradually increased, and the oil return effect of the unit is also improved at the moment. Through introducing the undulant controlled variable of pressure differential, and this controlled variable also is the negative value corresponding to the pressure differential change rate, this disclosed embodiment can suitably reduce the compressor rotational speed to the oil leakage phenomenon appears in can avoiding the compressor, is favorable to cooling water set's steady operation.
Optionally, the value range of the differential pressure influence coefficient is [0, 10]. The differential pressure influence coefficient can be selected according to the specific working condition of the water chilling unit so as to more accurately adjust the rotating speed of the compressor. Preferably, the differential pressure influence coefficient may be set to 2.
Optionally, the processor determines a differential pressure fluctuation control amount of the rotation speed of the compressor according to the differential pressure change rate and the differential pressure influence coefficient, and includes: the processor multiplies the pressure difference change rate and the pressure difference influence coefficient to obtain the pressure difference fluctuation control quantity of the rotating speed of the compressor. Thus, according to the embodiment of the disclosure, the influence of the frequency variation of the compressor on the oil return performance of the unit can be considered by monitoring the pressure difference change rate in the set time period. Through monitoring compressor suction and exhaust differential pressure's undulant condition to introduce corresponding controlled quantity, this disclosed embodiment can make the regulation of compressor rotational speed more accurate, thereby can avoid excessively adjusting to cause the compressor oil leakage phenomenon to appear, is favorable to the steady operation of cooling water set.
Optionally, the processor adjusts the rotation speed of the compressor according to the frequency load and unload control amount and the pressure difference fluctuation control amount, and includes: the processor determines the current rotating speed of the compressor; the processor adds the frequency load-reducing control quantity and the pressure difference fluctuation control quantity to obtain a total control quantity, and multiplies the total control quantity by a rotating speed value corresponding to a unit control quantity to obtain a rotating speed adjusting value of the compressor; and the processor obtains the target rotating speed of the compressor according to the current rotating speed and the rotating speed adjusting value, and controls the compressor to operate according to the target rotating speed. Therefore, by acquiring the frequency load and load increase and decrease control quantity and the pressure difference fluctuation control quantity, the embodiment of the disclosure can predict the influence of the regulation and control process on the operation stability of the water chilling unit from multiple aspects, so that the rotating speed of the compressor can be more accurately regulated. On the one hand, the water temperature can be controlled to be kept close to the expected value more accurately, and on the other hand, the stable operation of the water chilling unit is facilitated.
Optionally, the processor obtains the target rotation speed of the compressor according to the current rotation speed and the rotation speed adjustment value, and includes: and the processor adds the current rotating speed and the rotating speed adjusting value to obtain the target rotating speed of the compressor. In this way, the disclosed embodiments can simply and directly obtain the target rotation speed of the compressor. By controlling the compressor to operate at the target speed, the embodiments of the present disclosure can more accurately control the water temperature to be maintained near the desired value, while facilitating stable operation of the chiller.
Optionally, the processor obtains the target rotation speed of the compressor according to the current rotation speed and the rotation speed adjustment value, and includes: under the condition that the rotating speed adjusting value is larger than the upper limit value of the preset regulation and control interval, the processor adds the current rotating speed and the upper limit value of the preset regulation and control interval to obtain the target rotating speed of the compressor; or, under the condition that the rotating speed adjusting value is smaller than or equal to the upper limit value of the preset adjusting and controlling interval and is larger than or equal to the lower limit value of the preset adjusting and controlling interval, the processor adds the current rotating speed and the rotating speed adjusting value to obtain the target rotating speed of the compressor; or, under the condition that the rotating speed adjusting value is smaller than the lower limit value of the preset adjusting and controlling interval, the processor adds the current rotating speed and the lower limit value of the preset adjusting and controlling interval to obtain the target rotating speed of the compressor. Therefore, the increase or decrease of the rotating speed of the compressor motor can be reasonably controlled by comparing the rotating speed adjusting value with the preset adjusting and controlling interval. When the rotating speed adjusting value exceeds the preset adjusting range, the adjusting range is adjusted according to the preset adjusting range, so that the situation that the water temperature fluctuation is large or the unit operation is unstable due to the fact that the adjusting force is too large can be avoided.
Optionally, as shown in fig. 5, the processor adjusts the rotation speed of the compressor according to the frequency load and unload control amount and the pressure difference fluctuation control amount, and includes:
s501, the processor determines the current rotating speed of the compressor.
And S502, adding the frequency load and unload control quantity and the pressure difference fluctuation control quantity by the processor to obtain a total control quantity, and multiplying the total control quantity by a rotating speed value corresponding to the unit control quantity to obtain a rotating speed adjusting value of the compressor.
And S503, under the condition that the rotating speed adjusting value is larger than the upper limit value of the preset regulation and control interval, the processor adds the current rotating speed and the upper limit value of the preset regulation and control interval to obtain the target rotating speed of the compressor.
S504, under the condition that the rotating speed adjusting value is smaller than or equal to the upper limit value of the preset adjusting and controlling interval and larger than or equal to the lower limit value of the preset adjusting and controlling interval, the processor adds the current rotating speed and the rotating speed adjusting value to obtain the target rotating speed of the compressor.
And S505, adding the current rotating speed and the lower limit value of the preset regulation and control interval by the processor under the condition that the rotating speed regulation value is smaller than the lower limit value of the preset regulation and control interval to obtain the target rotating speed of the compressor.
And S506, controlling the compressor to operate according to the target rotating speed by the processor.
Therefore, by acquiring the frequency load and load increase and decrease control quantity and the pressure difference fluctuation control quantity, the embodiment of the disclosure can predict the influence of the regulation and control process on the operation stability of the water chilling unit from multiple aspects, so that the rotating speed of the compressor can be more accurately regulated. On the one hand, the water temperature can be controlled to be kept close to the expected value more accurately, and on the other hand, the stable operation of the water chilling unit is facilitated. Meanwhile, the increase or decrease of the rotating speed of the compressor motor can be reasonably controlled by comparing the rotating speed adjusting value with the preset adjusting and controlling interval. When the rotational speed regulating value surpassed and predetermine the regulation and control interval, this disclosed embodiment adjusts and controls according to predetermined adjustment range to can avoid the too big condition that causes the temperature fluctuation great or the unit operation unstable of adjustment dynamics.
As shown in fig. 6, an apparatus for controlling a chiller according to an embodiment of the present disclosure includes a processor (processor) 601 and a memory (memory) 602. Optionally, the apparatus may also include a Communication Interface 603 and bus 604. The processor 601, the communication interface 603, and the memory 602 may communicate with each other through the bus 604. Communication interface 603 may be used for information transfer. The processor 601 may call logic instructions in the memory 602 to perform the method for controlling the chiller, of the above embodiment.
Furthermore, the logic instructions in the memory 602 may be implemented in software functional units and stored in a computer readable storage medium when the logic instructions are sold or used as independent products.
The memory 602 is a computer-readable storage medium and can be used for storing software programs, computer-executable programs, such as program instructions/modules corresponding to the methods in the embodiments of the present disclosure. The processor 601 executes functional applications and data processing by executing program instructions/modules stored in the memory 602, that is, implements the method for controlling the chiller in the above-described embodiment.
The memory 602 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, memory 602 may include high speed random access memory and may also include non-volatile memory.
The embodiment of the disclosure provides a water chilling unit, which comprises the device for controlling the water chilling unit.
The embodiment of the disclosure provides a storage medium, which stores computer executable instructions, and when the computer executable instructions are executed, the method for controlling the water chilling unit is executed.
The storage medium described above may be a transitory computer-readable storage medium or a non-transitory computer-readable storage medium.
The technical solution of the embodiments of the present disclosure may be embodied in the form of a software product, which is stored in a storage medium and includes one or more instructions for enabling a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present disclosure. And the aforementioned storage medium may be a non-transitory storage medium comprising: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes, and may also be a transient 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. Similarly, the term "and/or" as used in this application is meant to encompass any and all possible combinations of one or more of the associated listed. 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 a …" does not exclude the presence of additional 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 simplicity of description, the specific working processes of the above-described systems, apparatuses, and units 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 (11)

1. A method for controlling a chiller, comprising:
acquiring the frequency loading and unloading control quantity of the rotating speed of the compressor;
acquiring the pressure difference fluctuation control quantity of the rotating speed of the compressor;
and regulating the rotating speed of the compressor according to the frequency loading and unloading control quantity and the pressure difference fluctuation control quantity.
2. The method of claim 1, wherein the obtaining a frequency loading and unloading control amount of compressor speed comprises:
acquiring a PID (proportion integration differentiation) adjusting value of the rotating speed of the compressor corresponding to the frequency fluctuation amount;
determining an addition and subtraction load coefficient;
and determining the frequency load and unload control quantity of the rotating speed of the compressor according to the PID regulating value and the load and unload coefficient.
3. The method of claim 2, wherein the determining the add-subtract load factor comprises:
acquiring the current water temperature;
determining the average rotating speed of the compressor in the load increasing and reducing period;
and determining the load increasing and reducing coefficient according to the current water temperature and the average rotating speed.
4. The method of claim 3, wherein determining the load reduction factor based on the current water temperature and the average rotational speed comprises:
determining the load increasing and reducing coefficient as a first load increasing and reducing coefficient under the condition that the current water temperature is greater than or equal to the set water temperature and the average rotating speed is greater than the preset rotating speed; or,
determining the loading and unloading coefficient as a second loading and unloading coefficient under the condition that the current water temperature is greater than or equal to the set water temperature and the average rotating speed is less than or equal to the preset rotating speed; or,
determining the load increasing and reducing coefficient as a third load increasing and reducing coefficient under the condition that the current water temperature is less than the set water temperature and the average rotating speed is greater than the preset rotating speed; or,
and determining the loading and unloading coefficient as a fourth loading and unloading coefficient under the conditions that the current water temperature is less than the set water temperature and the average rotating speed is less than or equal to the preset rotating speed.
5. The method of claim 1, wherein said obtaining a differential pressure fluctuation control amount of compressor speed comprises:
acquiring the pressure difference change rate in a set time period;
determining a differential pressure influence coefficient;
and determining the pressure difference fluctuation control quantity of the rotating speed of the compressor according to the pressure difference change rate and the pressure difference influence coefficient.
6. The method of claim 5, wherein said obtaining a rate of change of differential pressure over a set period of time comprises:
continuously monitoring the suction pressure and the exhaust pressure of the compressor, and calculating the difference value of the suction pressure and the exhaust pressure to obtain a real-time pressure difference;
determining a first real-time pressure difference at the starting point of a set time period and a second real-time pressure difference at the end point of the set time period;
and acquiring the pressure difference change rate in a set time period according to the first real-time pressure difference and the second real-time pressure difference.
7. The method of any one of claims 1 to 6, wherein the adjusting the compressor speed in accordance with the frequency loading and unloading control amount and the pressure difference fluctuation control amount comprises:
determining the current rotating speed of the compressor;
adding the frequency load-shedding control quantity and the pressure difference fluctuation control quantity to obtain a total control quantity, and multiplying the total control quantity by a rotating speed value corresponding to a unit control quantity to obtain a rotating speed adjusting value of the compressor;
and obtaining the target rotating speed of the compressor according to the current rotating speed and the rotating speed adjusting value, and controlling the compressor to operate according to the target rotating speed.
8. The method of claim 7, wherein obtaining the target speed of the compressor according to the current speed and the speed adjustment value comprises:
adding the current rotating speed and the upper limit value of the preset regulation and control interval to obtain the target rotating speed of the compressor under the condition that the rotating speed adjustment value is larger than the upper limit value of the preset regulation and control interval; or,
adding the current rotating speed and the rotating speed adjusting value to obtain the target rotating speed of the compressor under the condition that the rotating speed adjusting value is smaller than or equal to the upper limit value of the preset adjusting and controlling interval and is larger than or equal to the lower limit value of the preset adjusting and controlling interval; or,
and under the condition that the rotating speed adjusting value is smaller than the lower limit value of the preset regulation and control interval, adding the current rotating speed to the lower limit value of the preset regulation and control interval to obtain the target rotating speed of the compressor.
9. 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 8 when executing the program instructions.
10. A chiller, characterized by comprising the device for controlling a chiller according to claim 9.
11. A storage medium storing program instructions which, when executed, perform a method for controlling a chiller according to any of claims 1 to 8.
CN202211034760.5A 2022-08-26 2022-08-26 Method and device for controlling water chilling unit, water chilling unit and storage medium Active CN115355640B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202211034760.5A CN115355640B (en) 2022-08-26 2022-08-26 Method and device for controlling water chilling unit, water chilling unit and storage medium

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202211034760.5A CN115355640B (en) 2022-08-26 2022-08-26 Method and device for controlling water chilling unit, water chilling unit and storage medium

Publications (2)

Publication Number Publication Date
CN115355640A true CN115355640A (en) 2022-11-18
CN115355640B CN115355640B (en) 2024-03-22

Family

ID=84004348

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202211034760.5A Active CN115355640B (en) 2022-08-26 2022-08-26 Method and device for controlling water chilling unit, water chilling unit and storage medium

Country Status (1)

Country Link
CN (1) CN115355640B (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011241760A (en) * 2010-05-18 2011-12-01 Mitsubishi Heavy Ind Ltd Motor-driven compressor, heat source machine, and method of controlling the heat source machine
CN104903660A (en) * 2012-12-28 2015-09-09 大金工业株式会社 Refrigeration device
CN111473466A (en) * 2020-04-21 2020-07-31 宁波奥克斯电气股份有限公司 Frequency control method and air conditioner
CN112432342A (en) * 2020-11-23 2021-03-02 珠海格力电器股份有限公司 Differential pressure control system and method of heat pump air conditioner and heat pump air conditioner
KR20220009052A (en) * 2020-07-15 2022-01-24 엘지전자 주식회사 Chiller system and method for operating the same
CN217236154U (en) * 2022-02-25 2022-08-19 青岛海尔智能技术研发有限公司 Refrigerating system and refrigerator

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011241760A (en) * 2010-05-18 2011-12-01 Mitsubishi Heavy Ind Ltd Motor-driven compressor, heat source machine, and method of controlling the heat source machine
CN104903660A (en) * 2012-12-28 2015-09-09 大金工业株式会社 Refrigeration device
CN111473466A (en) * 2020-04-21 2020-07-31 宁波奥克斯电气股份有限公司 Frequency control method and air conditioner
KR20220009052A (en) * 2020-07-15 2022-01-24 엘지전자 주식회사 Chiller system and method for operating the same
CN112432342A (en) * 2020-11-23 2021-03-02 珠海格力电器股份有限公司 Differential pressure control system and method of heat pump air conditioner and heat pump air conditioner
CN217236154U (en) * 2022-02-25 2022-08-19 青岛海尔智能技术研发有限公司 Refrigerating system and refrigerator

Also Published As

Publication number Publication date
CN115355640B (en) 2024-03-22

Similar Documents

Publication Publication Date Title
CN105387570A (en) Executive capability adjustment method and device of water chilling unit
US20170159652A1 (en) Method for Controlling a Compressor Installation
CN113251602B (en) Method and device for controlling air conditioner and intelligent air conditioner
CN107148541B (en) Heat source system, and control device and control method therefor
CN109681416B (en) Method for controlling cooling pump
CN112050346A (en) Method, device and equipment for controlling starting number of air conditioning system and air conditioning system
CN112432339B (en) Method and device for adjusting electronic expansion valve of air conditioner outdoor unit and outdoor unit
CN111043737A (en) Method and device for controlling expansion valve and air conditioner
CN113885600B (en) Method and device for controlling temperature of centrifugal machine, centrifugal machine and storage medium
CN114838530A (en) Control method and device for air conditioner electronic expansion valve, air conditioner and storage medium
CN113091231B (en) Control method and device for air conditioner and air conditioner
CN115355640A (en) Method and device for controlling water chilling unit, water chilling unit and storage medium
CN114060961B (en) Method and device for dehumidifying air conditioner, storage medium and air conditioner
CN111852832B (en) Water cooling unit for parallel cold water system and variable station number control method of water pump
CN116026071A (en) Method and device for controlling liquid cooling unit, liquid cooling unit and storage medium
CN115111731A (en) Method and device for controlling air conditioner and air conditioner
CN113707968A (en) Multi-branch high-voltage battery system and temperature difference control method and device thereof
CN113959128A (en) Control method and device for multi-handpiece water chilling unit, refrigeration equipment and medium
CN114838469A (en) Control method and control device of air conditioner and air conditioner
CN113672065B (en) Method and device for regulating speed of fan and storage medium
CN115507509A (en) Method and device for controlling water chiller unit, water chiller unit and storage medium
CN113959056B (en) Control method and control device for air conditioner and air conditioner
CN115726980A (en) Water pump operation control method, water pump control device and readable storage medium
CN115585624A (en) Control method and device for water chiller, water chiller and storage medium
CN113959077A (en) Control method and device for refrigeration equipment, refrigeration equipment and storage medium

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant