A method for controlling superheat degree in a multi-evaporator parallel connection

Abstract

The present application relates to power generation technology field, disclose a kind of overheat control methods of multiple evaporators parallel, comprising: obtaining the first temperature value of the entrance of multiple evaporators, first pressure value, multiple evaporators each corresponding multiple outlet of multiple second temperature values, multiple second pressure values;Determine overheat feedforward compensation value based on first temperature value and first pressure value;Determine overheat feedback value based on multiple second temperature values and multiple second pressure values;Overheat feedforward compensation value and overheat feedback value are based on and control the operating state of working medium pump, realize the coordinated control to power generation system overheat, can avoid multiple evaporator flow distribution uneven and dynamic imbalance problem, guarantee multiple evaporator stable operation, improve the overall performance and reliability of power generation system, simultaneously, without separately configuring multiple working medium pump, avoid the complex control problem brought by multiple control loop, reduce control complexity, and reduce the cost of power generation system, reduce space occupation.

Description

Technical Field

[0001] This invention relates to the field of power generation technology, and in particular to a method for controlling superheat in a multi-evaporator parallel connection. Background Technology

[0002] In the field of waste heat recovery, ORC (Organic Rankine Cycle) is an effective technology suitable for medium- and low-temperature waste heat recovery, applicable to industries such as steel, chemicals, power plant waste heat, and geothermal resources. In ORC power generation systems, superheat control at the evaporator outlet is particularly crucial. Excessive superheat can lead to liquid contamination of the working fluid at the expander inlet, causing equipment failure; excessive superheat significantly reduces heat source utilization and system efficiency.

[0003] In existing technologies, traditional ORC power generation systems can use a single evaporator or multiple evaporators. However, each evaporator outlet is equipped with an independent temperature / pressure sensor. The working fluid pump frequency is adjusted by a single-loop PID (Proportional Integral Derivative) controller corresponding to each evaporator outlet to maintain the target superheat. However, this control method can lead to uneven flow distribution among multiple evaporators and dynamic imbalance of working fluid flow. Furthermore, single-loop PID control requires an independent working fluid pump for each evaporator to independently adjust the superheat and ensure the stability of superheat in each branch, which significantly increases the cost and space occupation of the power generation system. In addition, power generation systems with multiple working fluid pumps may introduce additional control complexity. Summary of the Invention

[0004] This invention aims to at least solve one of the technical problems existing in the prior art. Therefore, the purpose of this invention is to propose a superheat control method for multiple evaporators connected in parallel. This method can avoid uneven flow distribution and dynamic imbalance among multiple evaporators, ensure stable operation of multiple evaporators, improve the overall performance and reliability of the power generation system, and eliminate the need for separate configuration of multiple working fluid pumps, thus avoiding the complex control problems caused by multiple control loops, reducing control complexity, lowering the cost of the power generation system, and reducing space occupation.

[0005] This invention proposes a superheat control method for multiple evaporators connected in parallel. This method is used in a power generation system, which includes multiple evaporators connected in parallel and a working fluid pump connected to the multiple evaporators. The method includes the following steps: The first temperature value at the inlet of the plurality of evaporators, the first pressure value at the inlet of the plurality of evaporators, the plurality of second temperature values ​​at the plurality of outlets corresponding to each of the plurality of evaporators, and the plurality of second pressure values ​​at the plurality of outlets corresponding to each of the plurality of evaporators are obtained. The superheat feedforward compensation value is determined based on the first temperature value and the first pressure value; The superheat feedback value is determined based on the plurality of second temperature values ​​and the plurality of second pressure values; The operating state of the working fluid pump is controlled based on the superheat feedforward compensation value and the superheat feedback value to achieve coordinated control of the superheat of the power generation system.

[0006] In addition, the superheat control method for multiple evaporators connected in parallel according to embodiments of the present invention may also have the following additional technical features: Further, determining the superheat feedforward compensation value based on the first temperature value and the first pressure value includes: determining the saturation temperature value corresponding to the first pressure value based on a pre-trained first working fluid property model, wherein the first working fluid property model is trained based on the correspondence between multiple sets of first pressure values ​​and saturation temperature values; and determining the superheat feedforward compensation value based on the saturation temperature value corresponding to the first temperature value and the first pressure value.

[0007] Further, determining the superheat feedback value based on the plurality of second temperature values ​​and the plurality of second pressure values ​​includes: determining a plurality of saturation temperature values ​​corresponding to the plurality of second pressure values ​​based on a pre-trained second working fluid property model, wherein the second working fluid property model is trained based on the correspondence between multiple sets of second pressure values ​​and saturation temperature values; and determining the superheat feedback value based on the plurality of second temperature values ​​and the plurality of saturation temperature values.

[0008] Further, determining the superheat feedback value based on the plurality of second temperature values ​​and the plurality of saturation temperature values ​​includes: determining a plurality of superheat values ​​based on the plurality of second temperature values ​​and the plurality of saturation temperature values; and determining the superheat feedback value based on the plurality of superheat values.

[0009] Further, determining the superheat feedback value based on the plurality of superheat values ​​includes: comparing the plurality of superheat values ​​and determining the minimum value among the plurality of superheat values ​​as the superheat feedback value.

[0010] Furthermore, controlling the operating state of the working fluid pump based on the superheat feedforward compensation value and the superheat feedback value includes: superimposing the superheat feedforward compensation value and the superheat feedback value to obtain a superimposed superheat value; and controlling the operating state of the working fluid pump based on the superimposed superheat value.

[0011] Furthermore, controlling the operating state of the working fluid pump based on the superheat superposition value includes: determining a superheat deviation value based on the superheat superposition value and a preset superheat value; inputting the superheat deviation value into a PID controller to output a frequency for controlling the operation of the working fluid pump; and controlling the operation of the working fluid pump based on the frequency to achieve coordinated control of the superheat of the power generation system.

[0012] The superheat control method for multiple evaporators in parallel according to embodiments of the present invention, by comprehensively considering the temperature and pressure data of the inlet and outlet of multiple evaporators, and coordinating the control of the working fluid pump based on feedforward compensation values ​​and feedback values, can avoid uneven flow distribution and dynamic imbalance among multiple evaporators, ensure stable operation of multiple evaporators, improve the overall performance and reliability of the power generation system, and at the same time, eliminate the need to separately configure multiple working fluid pumps, avoid the complex control problems caused by multiple control loops, reduce control complexity, reduce the cost of the power generation system, and reduce space occupation.

[0013] To address the aforementioned problems, a second aspect of the present invention provides a superheat control device for multiple evaporators connected in parallel. This device is used in a power generation system, which includes multiple evaporators connected in parallel and a working fluid pump connected to each evaporator. The superheat control device comprises: an acquisition module for acquiring a first temperature value at the inlet of each evaporator, a first pressure value at the inlet of each evaporator, multiple second temperature values ​​at multiple outlets corresponding to each evaporator, and multiple second pressure values ​​at multiple outlets corresponding to each evaporator; a first determination module for determining a superheat feedforward compensation value based on the first temperature value and the first pressure value; a second determination module for determining a superheat feedback value based on the multiple second temperature values ​​and the multiple second pressure values; and a control module for controlling the operating state of the working fluid pump based on the superheat feedforward compensation value and the superheat feedback value, thereby achieving coordinated control of the superheat of the power generation system.

[0014] The superheat control device for multiple evaporators in parallel according to embodiments of the present invention, by comprehensively considering the temperature and pressure data of the inlet and outlet of multiple evaporators, coordinates the control of the working fluid pump based on feedforward compensation values ​​and feedback values, which can avoid uneven flow distribution and dynamic imbalance among multiple evaporators, ensure stable operation of multiple evaporators, improve the overall performance and reliability of the power generation system, and at the same time, eliminate the need to configure multiple working fluid pumps separately, avoid the complex control problems caused by multiple control loops, reduce control complexity, reduce the cost of the power generation system, and reduce space occupation.

[0015] To address the aforementioned problems, a third aspect of the present invention provides a power generation system comprising: a superheat control device for multiple evaporators connected in parallel as described in a second aspect of the present invention.

[0016] According to the power generation system of the present invention, by comprehensively considering the temperature and pressure data of multiple evaporator inlets and outlets, and coordinating the control of the working fluid pump based on feedforward compensation values ​​and feedback values, the problem of uneven flow distribution and dynamic imbalance among multiple evaporators can be avoided, ensuring the stable operation of multiple evaporators, improving the overall performance and reliability of the power generation system. At the same time, it eliminates the need to separately configure multiple working fluid pumps, avoids the complex control problems caused by multiple control loops, reduces control complexity, reduces the cost of the power generation system, and reduces space occupation.

[0017] To achieve the above objectives, a fourth aspect of the present invention discloses a computer-readable storage medium storing a superheat control program for multiple evaporators connected in parallel. When executed by a processor, the superheat control program for multiple evaporators connected in parallel implements the superheat control method for multiple evaporators connected in parallel as described in the first aspect of the present invention.

[0018] According to embodiments of the present invention, when a superheat control program for multiple evaporators in parallel, stored on a computer-readable storage medium, is executed by a processor, it comprehensively considers the temperature and pressure data at the inlet and outlet of multiple evaporators and coordinates the control of the working fluid pump based on feedforward compensation values ​​and feedback values. This avoids uneven flow distribution and dynamic imbalance among multiple evaporators, ensures stable operation of multiple evaporators, and improves the overall performance and reliability of the power generation system. At the same time, it eliminates the need for separate configuration of multiple working fluid pumps, avoids the complex control problems caused by multiple control loops, reduces control complexity, lowers the cost of the power generation system, and reduces space occupation.

[0019] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is a schematic diagram of a power generation system according to an embodiment of the present invention; Figure 2 This is a schematic flowchart of a superheat control method for multiple evaporators connected in parallel according to an embodiment of the present invention; Figure 3 This is a schematic diagram of a superheat control device for multiple evaporators connected in parallel according to an embodiment of the present invention.

[0021] Figure label: Superheat control device for multiple evaporators in parallel - 100; Acquisition module - 110; First determination module - 120; Second determination module - 130; Control module - 140; Waste heat flue gas inlet - 1; Waste heat flue gas outlet - 2; Flue-water heat exchanger - 3; Heat source pressure sensor - 4; Hot water pump - 5; Evaporator hot side temperature sensor - 6; Evaporator hot side pressure sensor - 7; Evaporator I - 8; Evaporator I working fluid side temperature sensor - 9; Evaporator I working fluid side pressure sensor Evaporator-10; Evaporator II-11; Evaporator II working fluid side temperature sensor-12; Evaporator II working fluid side pressure sensor-13; Working fluid pump-14; Bypass valve-15; Main steam valve-16; Working fluid tank-17; Turbine expander-18; Magnetic levitation generator set-19; Grid-connected inverter-20; Condenser-21; Condenser cold side temperature sensor-22; Condenser cold side pressure sensor-23; Cold water pump-24; Cold source pressure sensor-25; Cooling tower-26. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] The following is for reference. Figures 1-3 A method and apparatus for controlling superheat in a multi-evaporator parallel configuration according to embodiments of the present invention are described.

[0024] To provide a detailed explanation of the technical content of this invention, the power generation system involved in this invention will first be described in detail, such as... Figure 1 The power generation system includes multiple evaporators connected in parallel and a working fluid pump connected to the multiple evaporators. For example, the power generation system specifically includes a heat source cycle, a cold source cycle, and an organic working fluid cycle. The heat source cycle consists of a waste heat flue gas inlet 1, a waste heat flue gas outlet 2, a flue-water heat exchanger 3, a heat source pressure sensor 4, a hot water pump 5, an evaporator hot-side temperature sensor 6, an evaporator hot-side pressure sensor 7, evaporator I 8, and evaporator II 11. Evaporator I 8 and evaporator II 11 are connected in parallel to achieve heat exchange between the heat source and the organic working fluid.

[0025] The cold source circulation consists of a condenser 21, a condenser cold side temperature sensor 22, a condenser cold side pressure sensor 23, a cold water pump 24, a cold source pressure sensor 25, and a cooling tower 26, connected by metal pipes. The condenser 21 realizes the heat exchange between the cold source and the organic working fluid.

[0026] The organic working fluid circulation consists of the working fluid side temperature sensor 9 of evaporator I, the working fluid side pressure sensor 10 of evaporator I, the working fluid side temperature sensor 12 of evaporator II, the working fluid side pressure sensor 13 of evaporator II, the working fluid pump 14, the main steam valve 16, the bypass valve 15, the working fluid tank 17, and the turbine expander 18, which are connected by metal pipes. The magnetic levitation generator set 19 is connected to the grid-connected inverter 20 by a cable.

[0027] The above-mentioned automatic control process includes: system initialization, automatic superheat control, and adaptive power generation control of the heat source. The technical solution of the present invention is mainly aimed at automatic superheat control.

[0028] Figure 2 This is a schematic flowchart of a superheat control method for multiple evaporators connected in parallel according to an embodiment of the present invention. Figure 2 As shown, the control method includes the following steps: The system acquires the first temperature value at the inlet of multiple evaporators, the first pressure value at the inlet of multiple evaporators, the second temperature value at the corresponding outlet of each of the multiple evaporators, and the second pressure value at the corresponding outlet of each of the multiple evaporators.

[0029] Specifically, in the process of controlling superheat, the first temperature value and the first pressure value at the inlet of multiple evaporators can be obtained in real time through temperature and pressure sensors at the inlet of multiple evaporators. Furthermore, multiple second temperature values ​​and second pressure values ​​at the outlets of multiple evaporators can be obtained respectively through temperature and pressure sensors at the outlets of multiple evaporators. For example, combining... Figure 1 As shown, taking two parallel evaporators, namely evaporator I and evaporator II, as an example, the first temperature value and the first pressure value at the inlet of evaporator I and evaporator II can be obtained by the hot-side temperature sensor and the hot-side pressure sensor of evaporator I and evaporator II, respectively. Furthermore, the second temperature value and the second pressure value at the outlet of evaporator I can be obtained by the working fluid side temperature sensor and the working fluid side pressure sensor of evaporator I, and the second temperature value and the second pressure value at the outlet of evaporator II can be collected by the working fluid side temperature sensor and the working fluid side pressure sensor of evaporator II.

[0030] The superheat feedforward compensation value is determined based on the first temperature value and the first pressure value.

[0031] Specifically, after obtaining the first temperature value and the first pressure value, the superheat feedforward compensation value can be determined based on the first temperature value and the first pressure value. That is, in order to avoid the superheat from having a negative impact on the power generation process, thereby affecting the power generation efficiency of the power generation system, it is necessary to reflect the value of advanced compensation for the heat source.

[0032] The superheat feedback value is determined based on multiple second temperature values ​​and multiple second pressure values.

[0033] Specifically, after obtaining multiple second temperature values ​​and multiple second pressure values, a superheat feedback value can be determined based on the multiple second temperature values ​​and multiple second pressure values, so as to realize feedback control of superheat according to the feedback value, thereby achieving coordinated control of superheat.

[0034] The operating status of the working fluid pump is controlled based on the superheat feedforward compensation value and the superheat feedback value to achieve coordinated control of the superheat of the power generation system.

[0035] Specifically, after determining the superheat feedforward compensation value and the superheat feedback value, the operating state of the working fluid pump can be controlled according to the superheat feedforward compensation value and the superheat feedback value. This includes, but is not limited to, using the superheat feedforward compensation value and the superheat feedback value as input values ​​of the PID controller, and after PID adjustment, outputting the operating frequency of the working fluid pump to adjust the operating state of the working fluid pump, so as to achieve coordinated control of the superheat of the power generation system, so that the superheat at the outlet of all evaporators is dynamically maintained within a safe range, avoiding uneven flow distribution and dynamic imbalance among multiple evaporators, ensuring stable operation of multiple evaporators, and improving the overall performance and reliability of the power generation system.

[0036] In summary, the superheat control method for multiple evaporators in parallel according to embodiments of the present invention, by comprehensively considering the temperature and pressure data of the inlet and outlet of multiple evaporators, and coordinating the control of the working fluid pump based on feedforward compensation values ​​and feedback values, can avoid uneven flow distribution and dynamic imbalance among multiple evaporators, ensure stable operation of multiple evaporators, improve the overall performance and reliability of the power generation system, and at the same time, eliminate the need for separate configuration of multiple working fluid pumps, avoid the complex control problems caused by multiple control loops, reduce control complexity, reduce the cost of the power generation system, and reduce space occupation.

[0037] In one embodiment of the present invention, determining the superheat feedforward compensation value based on the first temperature value and the first pressure value includes: determining the saturation temperature value corresponding to the first pressure value based on a pre-trained first working fluid property model, wherein the first working fluid property model is trained based on the correspondence between multiple sets of first pressure values ​​and saturation temperature values; The superheat feedforward compensation value is determined based on the saturation temperature value corresponding to the first temperature value and the first pressure value.

[0038] Specifically, in the process of determining the superheat feedforward compensation value based on the first temperature value and the first pressure value, a working fluid property model can be established by using a large amount of experimental measurement data (multiple sets of first pressure values ​​and multiple saturation temperature values ​​corresponding to the multiple sets of first pressure values) and using a preset algorithm (such as polynomial fitting, neural network fitting, etc.). This is a pre-trained first working fluid property model, which is used to determine the saturation temperature value corresponding to the pressure value at the inlet of the evaporator, i.e., the saturation temperature value corresponding to the first pressure value, based on the pre-trained first working fluid property model.

[0039] Furthermore, the superheat feedforward compensation value can be determined based on the saturation temperature value corresponding to the first temperature value and the first pressure value. This includes, but is not limited to, performing a difference calculation on the saturation temperature value corresponding to the first temperature value and the first pressure value, and using the difference as the superheat feedforward compensation value. This superheat feedforward compensation value characterizes the trend of superheat change caused by heat source fluctuations and can be introduced into the input of the PID controller as a feedforward compensation quantity to achieve advance compensation for heat source disturbances.

[0040] In one embodiment of the present invention, determining the superheat feedback value based on multiple second temperature values ​​and multiple second pressure values ​​includes: determining multiple saturation temperature values ​​corresponding to multiple second pressure values ​​based on a pre-trained second working fluid property model, wherein the second working fluid property model is trained based on the correspondence between multiple sets of second pressure values ​​and saturation temperature values; The superheat feedback value is determined based on multiple second temperature values ​​and multiple saturation temperature values.

[0041] Specifically, in the process of determining the superheat feedback value based on multiple second temperature values ​​and multiple second pressure values, a working fluid property model can be established by using a large amount of experimental measurement data (multiple sets of second pressure values ​​and multiple saturation temperature values ​​corresponding to the multiple sets of second pressure values) and using a preset algorithm (such as polynomial fitting, neural network fitting, etc.). This is a pre-trained second working fluid property model, which is used to determine the saturation temperature value corresponding to the pressure value at the outlet of the evaporator, i.e., the saturation temperature value corresponding to the second pressure value, based on the pre-trained second working fluid property model.

[0042] Furthermore, the superheat feedback value can be determined based on the saturation temperature values ​​corresponding to multiple second temperature values ​​and multiple second pressure values, including but not limited to performing a difference calculation on the saturation temperature values ​​corresponding to the second temperature values ​​and the second pressure values ​​to obtain multiple differences, and determining the superheat feedback value based on the multiple differences.

[0043] In one embodiment of the present invention, determining a superheat feedback value based on a plurality of second temperature values ​​and a plurality of saturation temperature values ​​includes: determining a plurality of superheat values ​​based on a plurality of second temperature values ​​and a plurality of saturation temperature values; and determining a superheat feedback value based on a plurality of superheat values.

[0044] Specifically, in the process of determining the superheat feedback value based on multiple second temperature values ​​and multiple saturation temperature values, multiple superheat values ​​can be determined first based on multiple second temperature values ​​and multiple saturation temperature values, including but not limited to subtracting multiple second temperature values ​​at the outlet of the evaporator from multiple saturation temperature values ​​calculated by the working fluid property model, and using the resulting multiple differences as multiple superheat values; furthermore, the superheat feedback value can be determined based on multiple superheat values.

[0045] In one embodiment of the present invention, determining a superheat feedback value based on multiple superheat values ​​includes: comparing multiple superheat values ​​and determining the minimum value among the multiple superheat values ​​as the superheat feedback value.

[0046] Specifically, when determining the superheat feedback value based on multiple superheat values, these values ​​can be compared one by one to determine the minimum value, which is then used as the superheat feedback value. For example, with two parallel evaporators, two superheat values ​​can be calculated separately, and the smaller of the two can be selected as the superheat feedback value.

[0047] In one embodiment of the present invention, controlling the operating state of the working fluid pump based on the superheat feedforward compensation value and the superheat feedback value includes: superimposing the superheat feedforward compensation value and the superheat feedback value to obtain a superimposed superheat value. The operating status of the working fluid pump is controlled based on the superposition value of superheat.

[0048] Specifically, in controlling the operating state of the working fluid pump based on the superheat feedforward compensation value and the superheat feedback value, the superheat feedforward compensation value and the superheat feedback value can be superimposed to obtain a superimposed superheat value, which provides a more comprehensive and accurate superheat value. It is understandable that feedforward control can quickly respond to external disturbances and reduce their impact on the power generation system output, while feedback control can eliminate the uncertainties inherent in feedforward control, ensuring a more accurate superheat value. Therefore, the superimposed superheat feedforward compensation value and the superheat feedback value can be superimposed to obtain a superimposed superheat value, and the operating state of the working fluid pump can be controlled based on this superimposed superheat value. This avoids uneven flow distribution and dynamic imbalance among multiple evaporators, ensures stable operation of multiple evaporators, and improves the overall performance and reliability of the power generation system.

[0049] In one embodiment of the present invention, controlling the operating state of the working fluid pump based on the superheat superposition value includes: determining a superheat deviation value based on the superheat superposition value and a preset superheat value; The temperature deviation value is input into the PID controller to output the frequency of the working fluid pump; the operation of the working fluid pump is controlled based on the frequency to achieve coordinated control of the superheat of the power generation system.

[0050] Specifically, in the process of controlling the operating status of the working fluid pump based on the superheat superposition value, the superheat deviation value can be determined based on the superheat superposition value and the preset superheat value. That is, the superheat deviation value = preset superheat value - superheat superposition value, which reflects the difference between the actual superheat and the theoretical superheat.

[0051] Furthermore, the superheat deviation value can be input into the PID controller to perform proportional, integral, and derivative operations on the superheat deviation value, thereby outputting the frequency of the working fluid pump's operation, i.e., how to adjust the working fluid pump.

[0052] Furthermore, the working fluid pump can be adjusted based on the operating frequency of the output working fluid pump to change the working fluid flow rate of the power generation system, thereby changing the superheat in the power generation system and achieving coordinated control of the superheat of the power generation system.

[0053] The superheat control method for multiple evaporators in parallel according to embodiments of the present invention, by comprehensively considering the temperature and pressure data of the inlet and outlet of multiple evaporators, and coordinating the control of the working fluid pump based on feedforward compensation values ​​and feedback values, can avoid uneven flow distribution and dynamic imbalance among multiple evaporators, ensure stable operation of multiple evaporators, improve the overall performance and reliability of the power generation system, and at the same time, eliminate the need to separately configure multiple working fluid pumps, avoid the complex control problems caused by multiple control loops, reduce control complexity, reduce the cost of the power generation system, and reduce space occupation.

[0054] A second aspect of the present invention provides a superheat control device 100 for multiple evaporators connected in parallel. This device 100 is used in a power generation system, which includes multiple evaporators connected in parallel and a working fluid pump connected to each evaporator. Figure 3As shown, the superheat control device 100 for multiple evaporators in parallel includes: an acquisition module 110, used to acquire a first temperature value at the inlet of multiple evaporators, a first pressure value at the inlet of multiple evaporators, multiple second temperature values ​​at multiple outlets corresponding to each of the multiple evaporators, and multiple second pressure values ​​at multiple outlets corresponding to each of the multiple evaporators; a first determination module 120, used to determine a superheat feedforward compensation value based on the first temperature value and the first pressure value; a second determination module 130, used to determine a superheat feedback value based on multiple second temperature values ​​and multiple second pressure values; and a control module 140, used to control the operating state of the working fluid pump based on the superheat feedforward compensation value and the superheat feedback value, so as to achieve coordinated control of the superheat of the power generation system.

[0055] In some embodiments, when determining the superheat feedforward compensation value based on the first temperature value and the first pressure value, the first determining module 120 is specifically used to: determine the saturation temperature value corresponding to the first pressure value based on a pre-trained first working fluid property model, wherein the first working fluid property model is trained based on the correspondence between multiple sets of first pressure values ​​and saturation temperature values; and determine the superheat feedforward compensation value based on the saturation temperature value corresponding to the first temperature value and the first pressure value.

[0056] In some embodiments, when determining the superheat feedback value based on multiple second temperature values ​​and multiple second pressure values, the second determining module 130 is specifically used to: determine multiple saturation temperature values ​​corresponding to multiple second pressure values ​​based on a pre-trained second working fluid property model, wherein the second working fluid property model is trained based on the correspondence between multiple sets of second pressure values ​​and saturation temperature values; and determine the superheat feedback value based on multiple second temperature values ​​and multiple saturation temperature values.

[0057] In some embodiments, when determining a superheat feedback value based on a plurality of second temperature values ​​and a plurality of saturation temperature values, the second determining module 130 is specifically used to: determine a plurality of superheat values ​​based on a plurality of second temperature values ​​and a plurality of saturation temperature values; and determine a superheat feedback value based on a plurality of superheat values.

[0058] In some embodiments, when determining a superheat feedback value based on multiple superheat values, the second determining module 130 is specifically used to: compare multiple superheat values ​​and determine the minimum value among the multiple superheat values ​​as the superheat feedback value.

[0059] In some embodiments, when controlling the operating state of the working fluid pump based on the superheat feedforward compensation value and the superheat feedback value, the control module 140 is specifically used to: superimpose the superheat feedforward compensation value and the superheat feedback value to obtain a superimposed superheat value; and control the operating state of the working fluid pump based on the superimposed superheat value.

[0060] In some embodiments, when controlling the operating state of the working fluid pump based on the superheat superposition value, the control module 140 is specifically used to: determine the superheat deviation value based on the superheat superposition value and the preset superheat value; input the superheat deviation value into the PID controller to output the frequency for controlling the operation of the working fluid pump; and control the operation of the working fluid pump based on the frequency to achieve coordinated control of the superheat of the power generation system.

[0061] The superheat control device 100 for multiple evaporators in parallel according to an embodiment of the present invention, by comprehensively considering the temperature and pressure data of the inlet and outlet of multiple evaporators, coordinates the control of the working fluid pump based on feedforward compensation value and feedback value, which can avoid uneven flow distribution and dynamic imbalance among multiple evaporators, ensure the stable operation of multiple evaporators, improve the overall performance and reliability of the power generation system, and at the same time, eliminate the need to configure multiple working fluid pumps separately, avoid the complex control problems caused by multiple control loops, reduce control complexity, reduce the cost of the power generation system, and reduce space occupation.

[0062] A third aspect of the present invention provides a power generation system comprising: a superheat control device for multiple evaporators connected in parallel as described in a second aspect of the present invention.

[0063] According to the power generation system of the present invention, by comprehensively considering the temperature and pressure data of multiple evaporator inlets and outlets, and coordinating the control of the working fluid pump based on feedforward compensation values ​​and feedback values, the problem of uneven flow distribution and dynamic imbalance among multiple evaporators can be avoided, ensuring the stable operation of multiple evaporators, improving the overall performance and reliability of the power generation system. At the same time, it eliminates the need to separately configure multiple working fluid pumps, avoids the complex control problems caused by multiple control loops, reduces control complexity, reduces the cost of the power generation system, and reduces space occupation.

[0064] To achieve the above objectives, a fourth aspect of the present invention discloses a computer-readable storage medium storing a superheat control program for multiple evaporators connected in parallel. When executed by a processor, the superheat control program for multiple evaporators connected in parallel implements the superheat control method for multiple evaporators connected in parallel as described in the first aspect of the present invention.

[0065] According to embodiments of the present invention, when a superheat control program for multiple evaporators in parallel, stored on a computer-readable storage medium, is executed by a processor, it comprehensively considers the temperature and pressure data at the inlet and outlet of multiple evaporators and coordinates the control of the working fluid pump based on feedforward compensation values ​​and feedback values. This avoids uneven flow distribution and dynamic imbalance among multiple evaporators, ensures stable operation of multiple evaporators, and improves the overall performance and reliability of the power generation system. At the same time, it eliminates the need for separate configuration of multiple working fluid pumps, avoids the complex control problems caused by multiple control loops, reduces control complexity, lowers the cost of the power generation system, and reduces space occupation.

[0066] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0067] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A method for controlling superheat in a multi-evaporator parallel connection, characterized in that, The superheat control method for multiple evaporators connected in parallel is used in a power generation system, the power generation system comprising: multiple evaporators connected in parallel and a working fluid pump connected to the multiple evaporators, the method comprising the following steps: The first temperature value at the inlet of the plurality of evaporators, the first pressure value at the inlet of the plurality of evaporators, the plurality of second temperature values ​​at the plurality of outlets corresponding to each of the plurality of evaporators, and the plurality of second pressure values ​​at the plurality of outlets corresponding to each of the plurality of evaporators are obtained. Determining a superheat feedforward compensation value based on the first temperature value and the first pressure value includes: determining a first saturation temperature value corresponding to the first pressure value based on a pre-trained first working fluid property model, wherein the first working fluid property model is trained based on the correspondence between multiple sets of first pressure values ​​and first saturation temperature values; determining the superheat feedforward compensation value based on the first temperature value and the first saturation temperature value corresponding to the first pressure value; the superheat feedforward compensation value characterizes the trend of superheat change caused by heat source fluctuations. Multiple second saturation temperature values ​​corresponding to the multiple second pressure values ​​are determined based on a pre-trained second working fluid property model, wherein the second working fluid property model is trained based on the correspondence between multiple sets of second pressure values ​​and second saturation temperature values; multiple superheat values ​​are determined based on the multiple second temperature values ​​and the multiple second saturation temperature values, and the multiple superheat values ​​are compared to determine the minimum value among the multiple superheat values ​​as the superheat feedback value; The operating state of the working fluid pump is controlled based on the superheat feedforward compensation value and the superheat feedback value to achieve coordinated control of the superheat of the power generation system.

2. The superheat control method for multiple evaporators in parallel according to claim 1, characterized in that, The method of controlling the operating state of the working fluid pump based on the superheat feedforward compensation value and the superheat feedback value includes: The superheat feedforward compensation value and the superheat feedback value are superimposed to obtain the superheat superposition value. The operating status of the working fluid pump is controlled based on the superposition value of the superheat.

3. The superheat control method for multiple evaporators in parallel according to claim 2, characterized in that, The method of controlling the operating state of the working fluid pump based on the superheat superposition value includes: The superheat deviation value is determined based on the superimposed superheat value and the preset superheat value; The heat deviation value is input into the PID controller to output the frequency for controlling the operation of the working fluid pump; The operation of the working fluid pump is controlled based on the frequency to achieve coordinated control of the superheat of the power generation system.

4. A superheat control device for multiple evaporators connected in parallel, the superheat control device for multiple evaporators connected in parallel being used in a power generation system, the power generation system comprising: A plurality of evaporators connected in parallel and a working fluid pump connected to the plurality of evaporators, wherein the superheat control device for the plurality of evaporators connected in parallel includes: The acquisition module is used to acquire a first temperature value at the inlet of the plurality of evaporators, a first pressure value at the inlet of the plurality of evaporators, a plurality of second temperature values ​​at the plurality of outlets corresponding to each of the plurality of evaporators, and a plurality of second pressure values ​​at the plurality of outlets corresponding to each of the plurality of evaporators. The first determining module is used to determine a superheat feedforward compensation value based on the first temperature value and the first pressure value, including: determining a first saturation temperature value corresponding to the first pressure value based on a pre-trained first working fluid property model, wherein the first working fluid property model is trained based on the correspondence between multiple sets of first pressure values ​​and first saturation temperature values; determining the superheat feedforward compensation value based on the first temperature value and the first saturation temperature value corresponding to the first pressure value; the superheat feedforward compensation value characterizes the trend of superheat change caused by heat source fluctuations. The second determining module is used to determine multiple second saturation temperature values ​​corresponding to the multiple second pressure values ​​based on a pre-trained second working fluid property model, wherein the second working fluid property model is trained based on the correspondence between multiple sets of second pressure values ​​and second saturation temperature values; and to determine multiple superheat values ​​based on the multiple second temperature values ​​and the multiple second saturation temperature values, and to compare the multiple superheat values ​​to determine the minimum value among the multiple superheat values ​​as the superheat feedback value. The control module controls the operating state of the working fluid pump based on the superheat feedforward compensation value and the superheat feedback value, so as to achieve coordinated control of the superheat of the power generation system.

5. A power generation system, comprising: The superheat control device for multiple evaporators in parallel as described in claim 4.

6. A computer-readable storage medium storing a superheat control program for multiple evaporators connected in parallel, which is executable on a processor and, when executed by the processor, implements the superheat control method for multiple evaporators connected in parallel as described in any one of claims 1-3.

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