Intelligent performance testing method and system for multistage series Roots vapor compressor

Abstract

The invention provides an intelligent performance test method and system for a multistage series Roots vapor compressor. The method comprises the following steps: introducing vapor into equipment to be tested as a test medium; the to-be-tested equipment comprises a control unit, multiple stages of Roots vapor compressors connected in series, an interstage spraying device and a parameter detection unit; the opening degree of each valve in the pipeline valve assembly and the spraying water flow of the inter-stage spraying device are cooperatively controlled through the control unit, so that each stage of compressor in the to-be-tested equipment is stabilized at a preset test working condition point; after the to-be-tested equipment operates stably, acquiring steady-state operation data within a preset duration through a parameter detection unit; calculating a performance evaluation index of the to-be-tested equipment by using the steady-state operation data; the performance evaluation indexes comprise isentropic efficiency and / or volume efficiency of the compressor. The invention further provides a test system for implementing the method. According to the invention, through intelligent automatic control, the performance test of the multi-stage compressor is realized.

Description

Technical Field

[0001] This invention belongs to the field of compressor performance testing technology, and specifically relates to an intelligent performance testing method and system for multi-stage series Roots steam compressors. Background Technology

[0002] Mechanical vapor recompression (MVR) technology is increasingly widely used in the concentration of high-boiling-point, heat-sensitive materials (such as food and pharmaceuticals). Single-stage Roots steam compressors have limited temperature rise (typically below 20°C), making multi-stage series technology a key approach to meet process temperature rise requirements of 20-50°C and even higher. However, the performance verification of multi-stage series Roots steam compressors faces significant challenges.

[0003] Currently, performance tests for this type of compressor mostly use air as the medium, which differs significantly from the thermodynamic characteristics of actual steam conditions. This results in test data that cannot accurately reflect the equipment's performance in real-world applications, leading to low reliability. The testing process heavily relies on operator experience, requiring manual observation of instruments and manual adjustment of valves to control parameters such as pressure and temperature, resulting in issues like adjustment lag, poor accuracy, and low repeatability. Furthermore, multi-stage series systems operate under complex conditions, and abnormal conditions (such as over-temperature, over-pressure, and surge) can easily trigger cascading failures, making timely response difficult for manual monitoring and posing high safety risks to the equipment. The lack of a standardized testing method and dedicated system capable of simulating real steam conditions, automatically completing tests, and outputting authoritative performance data severely restricts the reliability verification and widespread application of multi-stage series technology.

[0004] Therefore, there is an urgent need to develop an intelligent testing solution that can accurately simulate working conditions, automatically control, ensure safety and reliability, and output quantitative performance evaluation indicators. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention proposes an intelligent performance testing method and system for multi-stage series Roots steam compressors, enabling fully automated and high-precision performance testing of the compressor under real steam media.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: An intelligent performance testing method for a multi-stage series Roots steam compressor includes the following steps: Steam is introduced into the device under test as the test medium; the device under test includes a control unit, a Roots steam compressor connected in series, an interstage spray device, and a parameter detection unit; The control unit coordinates the opening degree of each valve in the pipeline valve assembly and the spray water flow rate of the interstage spray device to stabilize the compressors at each stage in the equipment under test at the preset test operating point. After the equipment under test has been running stably, steady-state operating data within a preset time period is collected through the parameter detection unit. The steady-state operating data includes at least the inlet and outlet pressures, inlet and outlet temperatures, and input power of each stage of the compressor. The performance evaluation index of the device under test is calculated using the steady-state operating data; the performance evaluation index includes the isentropic efficiency and / or volumetric efficiency of the compressor.

[0007] The present invention also proposes a test system for implementing the method, comprising: a control unit, a multi-stage Roots steam compressor connected in series, an interstage spray device, and a parameter detection unit; the control unit is communicatively connected to the multi-stage Roots steam compressor, the interstage spray device, and the parameter detection unit, respectively. The multi-stage Roots steam compressor in series includes at least a first-stage compressor and a second-stage compressor connected in series; The interstage spraying device is installed between the connecting pipelines of two adjacent compressor stages and is used to spray atomized water into the compressed steam to control the outlet temperature of the compressor. The parameter detection unit is used to collect operating condition data in real time during the test process; it includes at least: pressure transmitters installed at the inlet and outlet of each stage of the compressor; temperature sensors installed at the inlet and outlet of each stage of the compressor; mass flow meters installed on the main steam pipeline; and vibration sensors installed on the compressor body. The control unit is used to coordinate the control of the opening degree of each valve in the pipeline valve assembly and the spray water flow rate of the interstage spray device, so that the compressors of each stage in the equipment under test are stabilized at the preset test operating point; the performance evaluation index of the equipment under test is calculated using the steady-state operation data; the performance evaluation index includes the isentropic efficiency and / or volumetric efficiency of the compressor.

[0008] The effects described in the invention are merely those of the embodiments, and not all the effects of the invention. One of the above technical solutions has the following advantages or beneficial effects: This invention proposes an intelligent performance testing method and system for multi-stage series Roots steam compressors. The method includes the following steps: introducing steam as the test medium into the equipment under test; the equipment under test includes a control unit, series-connected Roots steam compressors, interstage spraying devices, and a parameter detection unit; coordinating the control unit to control the opening degree of each valve in the pipeline valve assembly and the spray water flow rate of the interstage spraying device, stabilizing each stage of the compressor in the equipment under test at a preset test operating point; after the equipment under test has stabilized, collecting steady-state operating data within a preset time period through the parameter detection unit, the steady-state operating data including at least the inlet and outlet pressures, inlet and outlet temperatures, and input power of each stage of the compressor; calculating the performance evaluation indicators of the equipment under test using the steady-state operating data; the performance evaluation indicators include the isentropic efficiency and / or volumetric efficiency of the compressor. This invention also proposes a testing system for implementing this method. This invention achieves fully automatic, high-precision performance testing of the compressor under a real steam medium, establishing stable operating conditions through intelligent control, automatically collecting data and calculating key performance indicators, while ensuring the safety of the testing process, ultimately providing accurate and reliable data support for equipment design verification, performance evaluation, and optimization.

[0009] This invention uses real steam for testing and combines it with dynamic operating condition simulation technology to ensure that the test conditions are highly consistent with actual applications. The performance data obtained can be directly used for equipment selection and operating condition matching, making it highly authoritative.

[0010] This invention integrates multi-dimensional sensing and intelligent fault diagnosis models, enabling early warning and accurate identification of overpressure, overtemperature, and mechanical faults. Attached Figure Description

[0011] Figure 1 This is a flowchart of the intelligent performance testing method for a multi-stage series Roots steam compressor proposed in Embodiment 1 of the present invention; Figure 2 This is a detailed flowchart of the intelligent performance test of the first-stage Roots steam compressor proposed in Embodiment 1 of the present invention; Figure 3 This is a detailed flowchart of the intelligent performance testing of the two-stage Roots steam compressor proposed in Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the intelligent performance testing system for the multi-stage series Roots steam compressor proposed in Embodiment 2 of the present invention; Legend: 1-Inlet electric butterfly valve, 2-First pressure transmitter, 3-First temperature transmitter, 4-First spray ball valve, 5-Second pressure transmitter, 6-Second temperature transmitter, 7-First reflux butterfly valve, 8-Second spray ball valve, 9-Third temperature transmitter, 10-Third pressure transmitter, 11-Fourth temperature transmitter, 12-Second reflux butterfly valve, 13-Outlet butterfly valve. Detailed Implementation

[0012] To clearly illustrate the technical features of this solution, the invention will be described in detail below through specific embodiments and in conjunction with the accompanying drawings. The following disclosure provides many different embodiments or examples for implementing different structures of the invention. To simplify the disclosure of the invention, components and arrangements of specific examples are described below. Furthermore, reference numerals and / or letters may be repeated in different examples. This repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. It should be noted that the components illustrated in the drawings are not necessarily drawn to scale. Descriptions of well-known components, processing techniques, and processes are omitted in this invention to avoid unnecessarily limiting the invention.

[0013] Example 1 Embodiment 1 of this invention proposes an intelligent performance testing method for multi-stage series Roots steam compressors, which is used to solve the technical problems existing in the performance testing of Roots steam compressors in the prior art.

[0014] Figure 1 This is a flowchart of the intelligent performance testing method for a multi-stage series Roots steam compressor proposed in Embodiment 1 of the present invention; In step S1, steam is introduced into the device under test as the test medium; the device under test includes a control unit, a Roots steam compressor connected in series, an interstage spray device, and a parameter detection unit; Figure 4 This is a schematic diagram of the intelligent performance testing system for the multi-stage series Roots steam compressor proposed in Embodiment 2 of the present invention; In the equipment under test, the control unit adopts a PLC control system and a two-stage Roots steam compressor connected in series; the interstage spray device is set between the connecting pipelines of the two adjacent compressor stages; in this invention, the first spray water ball valve 4 is used to control the spray device in the first-stage Roots steam compressor; the second spray water ball valve 8 is used to control the spray device in the second-stage Roots steam compressor.

[0015] In this invention, a steam generator is provided, and a control unit is connected to the steam generator in communication. The control unit controls the steam generator located at the inlet electric butterfly valve 1 to work and generate steam.

[0016] The parameter detection unit is used to collect operating condition data in real time during the test process. In this invention, the parameter detection unit includes a first pressure transmitter 2, a first temperature transmitter 3, a second pressure transmitter 5, a second temperature transmitter 6, a third temperature transmitter 9, a third pressure transmitter 10, and a fourth temperature transmitter 11. It also includes a mass flow meter installed on the main steam pipeline and a vibration sensor installed on the compressor body.

[0017] The pipeline valve assembly includes inlet electric butterfly valves connected to the inlets of each stage of the compressor, bypass valves bridging the inlets and outlets of each stage of the compressor, and the system main return valve. For example... Figure 4 The valve consists of an inlet electric butterfly valve 1, a first reflux butterfly valve 7, a second reflux butterfly valve 12, and an outlet butterfly valve 13.

[0018] The scope of protection of this invention is not limited to the two-stage Roots steam compressor in series proposed in Example 1. Those skilled in the art can choose more stages of Roots steam compressor in series according to the actual situation.

[0019] In step S2, the control unit coordinates the opening degree of each valve in the pipeline valve assembly and the spray water flow rate of the interstage spray device to stabilize the compressors at each stage in the equipment under test at the preset test operating point. This invention is illustrated using the parameters of increasing the design temperature from 70°C to 120°C and increasing the pressure from -70 kPa to 200 kPa (A) as an example. The scope of protection of this invention is not limited to the temperatures listed in Example 1.

[0020] The control unit controls the opening degree of each valve in the pipeline valve assembly. Specifically, it first controls the first return butterfly valve 7 of the first-stage compressor to gradually close, while simultaneously adjusting the opening degree of its inlet electric butterfly valve 1, until the inlet pressure of the first-stage compressor reaches the first-stage design value and stabilizes. Then, it controls the second return butterfly valve 12 of the second-stage compressor to gradually close, while simultaneously adjusting the opening degree of its inlet electric butterfly valve, until the outlet pressure of the second-stage compressor reaches the second-stage design value and stabilizes. For example, the first-stage design value is -30 kPa, and the second-stage design value is 200 kPa.

[0021] The control unit performs the first-stage loading: gradually closing the first return butterfly valve 7 while fine-tuning the inlet electric butterfly valve 1. Through feedback from the first pressure transmitter 2, the first-stage inlet pressure is stabilized at the design value of -30 kPa (gauge pressure). After the first-stage pressure stabilizes, the control unit performs the second-stage loading: gradually closing the second return butterfly valve 12 while adjusting the relevant second-stage valves. Through feedback from the third pressure transmitter 10, the second-stage outlet pressure steadily rises to 200 kPa and stabilizes.

[0022] The control unit controls the spray water flow rate of the interstage spray device to stabilize each stage of the compressor in the test equipment at the preset test operating point. Specifically, the control unit dynamically adjusts the spray water flow rate of the corresponding interstage spray device according to the deviation between the outlet temperature of each stage compressor and the target temperature collected in real time, so as to control the outlet temperature of each stage compressor within the preset temperature range.

[0023] The process of dynamically adjusting the spray water flow rate of the corresponding interstage spray device specifically includes: inputting the deviation value between the outlet temperature of each stage compressor and the target temperature into a preset control model, which is based on a PID neural network algorithm and trained using historical experimental data; the control model performs autonomous calculation and learning based on the input deviation value and outputs the optimal control command, which includes the target spray water flow rate adjustment amount and the corresponding valve opening adjustment amount; the control unit drives the corresponding spray water regulating valve to perform opening adjustment according to the optimal control command.

[0024] The PID neural network algorithm in this invention is an algorithm that combines a traditional PID controller with a neural network, consisting of three parts: an input layer, a hidden layer (PID layer), and an output layer. The input layer consists of 2 neurons, the hidden layer consists of 3 neurons: P / I / D, and the output layer consists of 1 neuron.

[0025] In the implementation of this invention, the first neuron of the input layer receives the temperature deviation value at the current moment; the second neuron of the input layer receives the temperature deviation value at the previous moment; the hidden layer contains three neurons with specific functions, corresponding to the three components of PID control respectively; and one neuron of the output layer corresponds to the output of the optimal control command.

[0026] The second temperature transmitter 6 monitors the outlet temperature of the primary compressor in real time, and the fourth temperature transmitter 11 monitors the outlet temperature of the secondary compressor in real time. If the primary outlet temperature is higher than the set value, the control unit calls the built-in PID neural network model to calculate and execute the optimal adjustment of the opening of the first spray water ball valve 4, increasing the spray to lower the temperature. The secondary temperature control works similarly, adjusted through the second spray water ball valve 8. This process continues until all pressure and temperature parameters stabilize within the tolerance range of the set values ​​for at least 120 seconds, at which point the system is declared to have reached stability. The scope of protection of this invention is not limited to the specific stabilization time listed in Example 1; those skilled in the art can make reasonable adjustments according to the actual situation.

[0027] In step S3, after the equipment under test has been running stably, steady-state operating data within a preset time period is collected through the parameter detection unit. The steady-state operating data includes at least the inlet and outlet pressures, inlet and outlet temperatures, and input power of each stage of the compressor. The steady-state operating data in this invention also includes the steam mass flow rate through the equipment under test, as well as the vibration amplitude of each stage of the compressor collected by vibration sensors. The sampling frequency can reach 100Hz, achieving full-dimensional, high-fidelity acquisition of operating data.

[0028] The Kalman filter algorithm is used to denoise the collected raw data, eliminating abnormal data caused by electromagnetic interference, sensor drift, etc. The data normalization process maps parameters of different dimensions to the [0,1] interval, providing high-quality data input for subsequent fault diagnosis models.

[0029] In step S4, the performance evaluation index of the device under test is calculated using steady-state operating data; the performance evaluation index includes the isentropic efficiency and / or volumetric efficiency of the compressor.

[0030] The performance evaluation indicators of the device under test are calculated using steady-state operating data, specifically including: isentropic efficiency The calculation process is as follows: Based on the aforementioned inlet pressure Export pressure Inlet temperature Based on the steam properties, the isentropic compression work was calculated; the isentropic compression work was then compared with the input power. Perform ratio calculations to obtain isentropic efficiency; ; in, It is isentropic efficiency; In order to meet import pressure and inlet temperature The specific enthalpy of the vapor was found; In order to meet import pressure and inlet temperature The specific entropy of the steam was obtained; In order to alleviate export pressure The entropy value is maintained below Theoretical vapor enthalpy at that time; This is the steam mass flow rate, expressed in kg / s.

[0031] Volumetric efficiency The calculation process is as follows: The volumetric efficiency is obtained by calculating the ratio of the compressor's theoretical discharge capacity to the actual intake steam volume flow rate. ; ; in, This represents the actual volumetric flow rate of the steam being drawn in. This represents the theoretical displacement of the compressor. In order to meet import pressure and inlet temperature The obtained steam density, This refers to the theoretical displacement of the compressor; This refers to the operating speed of the compressor.

[0032] In step S5, the steady-state operation data of the device under test is monitored in real time, and the vibration, temperature change curves and parameter change rates are analyzed through a preset fault diagnosis model. If a fault feature or parameter exceeds the safety threshold, an automatic protection action is triggered.

[0033] The vibration, temperature change curves, and parameter change rates are analyzed using a pre-set fault diagnosis model, specifically including: Time-frequency analysis is performed on the vibration signal to extract vibration characteristics; instantaneous values ​​of temperature, pressure, and flow are obtained, and the rates of change of temperature, pressure, and flow are calculated. The instantaneous temperature and pressure values ​​are compared with preset safety thresholds in real time. If either parameter exceeds its corresponding safety threshold range, a primary anomaly flag is generated. The vibration characteristics, temperature change rate, pressure change rate, and flow change rate are input into a preset fault diagnosis model. The fault diagnosis model is a classifier trained based on a machine learning algorithm, which is used to perform pattern recognition on the input features and output the confidence level corresponding to different fault modes. If the confidence level of any fault mode exceeds a preset judgment threshold, a secondary abnormality flag is generated and a specific fault type identifier is output.

[0034] The fault diagnosis model in this invention uses a Support Vector Machine (SVM) classifier. The specific process is as follows: During each diagnostic cycle, real-time signals from vibration, temperature, pressure, and flow sensors are simultaneously acquired and processed as follows: time-domain and frequency-domain analysis is performed on the vibration signals to extract at least 10-dimensional vibration features, including peak value, root mean square value, kurtosis, and bearing fault characteristic frequency amplitude; the first-order rate of change and the slope of the linear trend over a preset time period are calculated for the temperature and pressure signals; all extracted features are standardized to form a standardized multi-dimensional feature vector. Standardized feature vectors are input into a pre-trained SVM model. The SVM model employs a radial basis function kernel, implements multi-class classification through a one-to-one strategy, and uses Platt scaling to output probability values ​​corresponding to different fault modes. The probability values ​​output by the model constitute a confidence vector, where the first 8 bits correspond to 8 predefined fault modes, and the 9th bit corresponds to the normal state. The 8 fault modes include overpressure fault, overtemperature fault, abnormal friction fault, bearing damage fault, surge fault, stall fault, seal failure fault, and sprinkler system fault.

[0035] The scope of protection of this invention is not limited to the listed fault types, and those skilled in the art can make reasonable definitions based on the actual situation.

[0036] If the 9th digit is greater than 0.85 and is the maximum value, then the system is considered to be in a normal state. Otherwise, find the maximum probability value and its corresponding fault category index; If the maximum probability value is greater than the preset judgment threshold, the corresponding fault mode is determined to have occurred, and a secondary anomaly flag is generated. The secondary anomaly flag is a structured data object, which at least includes a fault type identifier, confidence level, timestamp, and key feature evidence that led to the judgment.

[0037] The generated secondary anomaly flag is transmitted to the control unit in real time.

[0038] The scope of protection of this invention is not limited to the models listed in Example 1, and those skilled in the art can make reasonable selections based on the actual situation.

[0039] If a fault characteristic or parameter is detected that exceeds a safety threshold, an automatic protection action is triggered; specifically including: If an overpressure anomaly is detected, the bypass valve of the corresponding compressor is opened to a preset opening degree. If the pressure does not drop within a preset time, the opening degree is further increased. For example, the bypass valve of the corresponding compressor is first opened to 50%. If the pressure does not drop within 200 seconds, the bypass valve is fully opened and frequency reduction is started.

[0040] If an overheating anomaly is detected, enhanced spraying and reflux will be implemented; for example, the opening of the spray water valves of this stage and the upstream stage will be increased to the maximum, and the opening of the reflux valve will be increased to 70% simultaneously.

[0041] If abnormal friction is detected, a load reduction shutdown is performed; for example, the system load is immediately reduced to 10% in sequence, and a soft shutdown is performed within 30 seconds.

[0042] If surge or shutdown is detected, an emergency shutdown should be performed. For example, immediately disconnect the compressor's main power supply and fully open all bypass and return valves.

[0043] The scope of protection of this invention is not limited to the values ​​listed in Example 1, and those skilled in the art can make reasonable adjustments based on the actual situation.

[0044] Combination Figure 4 The given test system, Figure 2 This is a detailed flowchart of the intelligent performance test of the first-stage Roots steam compressor proposed in Embodiment 1 of the present invention; Figure 3 This is a detailed flowchart of the intelligent performance test of the two-stage Roots steam compressor proposed in Embodiment 1 of the present invention.

[0045] The process begins, and the compressor mechanical seal water, compressor inlet spray water, and compressor oil tank cooling water are automatically turned on in sequence.

[0046] Adjust the inlet electric butterfly valve 1, the first return butterfly valve 7, and the second return butterfly valve 12 to the fully open position. Simultaneously, start the steam generator. This step clears the system piping, establishes a steam circulation path, and begins generating test steam. At this time, the compressor is under no-load or low back pressure.

[0047] The primary and secondary compressors are automatically started via frequency converter control. The first spray water ball valve 4 is fully open, the inlet electric butterfly valve 1 and the first return butterfly valve 7 are fully open, the second spray water ball valve 8 is fully open, the second return butterfly valve 12 and the outlet butterfly valve 13 are fully open, and the primary and secondary compressors start up and run synchronously. After the compressor starts, the system continuously monitors its operating status and checks for any abnormalities, such as abnormal vibrations, unusual noises, or abnormal friction sounds. If the status is normal, the control unit gradually closes the outlet butterfly valve 13. If the status remains normal after adjusting the outlet valve, the first return butterfly valve 7 and the second return butterfly valve 12 are gradually closed.

[0048] Steady-state operating data is collected within a preset time period through the parameter detection unit. If the pressure or temperature reaches the design value, the reflux valve is stopped and closed, indicating that the system has stabilized at the target operating condition. If the compressor outlet temperature exceeds the limit, the opening degree of the first spray water ball valve 4 and the second spray water ball valve 8 is dynamically adjusted to increase the spray water volume for precise cooling.

[0049] Once an anomaly or overpressure is detected, the process immediately jumps to the protection branch.

[0050] It will immediately issue an audible and visual alarm and will likely execute preset protection procedures, such as stopping the current valve operation, maintaining or opening the valve, or even performing a tiered shutdown.

[0051] The scope of protection of this invention is not limited to the two-stage Roots steam compressor listed in Example 1.

[0052] The intelligent performance testing method for a multi-stage series Roots steam compressor proposed in Embodiment 1 of this invention enables fully automatic and high-precision performance testing of the compressor under real steam medium. It establishes stable operating conditions through intelligent control, automatically collects data and calculates key performance indicators, and ensures the safety of the testing process. Ultimately, it provides accurate and reliable data support for the design verification, performance evaluation and optimization of the equipment.

[0053] Example 2 Embodiment 2 of the present invention also proposes a test system for implementing the method described in Embodiment 1. The system includes: a control unit, a multi-stage Roots steam compressor connected in series, an interstage spray device, and a parameter detection unit; the control unit is communicatively connected to the multi-stage Roots steam compressor, the interstage spray device, and the parameter detection unit respectively. A multi-stage Roots steam compressor in series includes at least a first-stage compressor and a second-stage compressor connected in series; Interstage spraying devices are installed between the connecting pipelines of two adjacent compressor stages to spray atomized water into the compressed steam in order to control the compressor outlet temperature. The parameter detection unit is used to collect operating condition data in real time during the test process; it includes at least: pressure transmitters installed at the inlet and outlet of each stage of the compressor; temperature sensors installed at the inlet and outlet of each stage of the compressor; mass flow meters installed on the main steam pipeline; and vibration sensors installed on the compressor body. The control unit is used to coordinate the opening degree of each valve in the pipeline valve assembly and the spray water flow rate of the interstage spray device, so that the compressors of each stage in the equipment under test are stabilized at the preset test operating point; the performance evaluation index of the equipment under test is calculated using steady-state operating data; the performance evaluation index includes the isentropic efficiency and / or volumetric efficiency of the compressor.

[0054] Figure 4 This is a schematic diagram of the intelligent performance testing system for the multi-stage series Roots steam compressor proposed in Embodiment 2 of the present invention; The first spray water ball valve 4 is used to control the spray device in the first-stage Roots steam compressor; the second spray water ball valve 8 is used to control the spray device in the second-stage Roots steam compressor.

[0055] The parameter detection unit includes a first pressure transmitter 2, a first temperature transmitter 3, a second pressure transmitter 5, a second temperature transmitter 6, a third temperature transmitter 9, a third pressure transmitter 10, and a fourth temperature transmitter 11.

[0056] The pipeline valve assembly includes an inlet electric butterfly valve connected to the inlet of each stage of the compressor, a bypass valve bridging the inlet and outlet of each stage of the compressor, and a system main return valve. Figure 4 The valve consists of an inlet electric butterfly valve 1, a first reflux butterfly valve 7, a second reflux butterfly valve 12, and an outlet butterfly valve 13.

[0057] The specific working process of this system includes: the control unit adopts a PLC control system, which controls the steam generator located at the inlet electric butterfly valve 1 to generate steam. The first spray water ball valve 4 is fully open, the inlet electric butterfly valve 1 and the first return butterfly valve 7 are fully open, the second spray water ball valve 8 is fully open, the second return butterfly valve 12 and the outlet butterfly valve 13 are opened, and the primary and secondary compressors start up and run synchronously.

[0058] The first return butterfly valve 7 is gradually closed under the control of the control unit until it is completely closed. The inlet electric butterfly valve 1 begins to close, and the first pressure transmitter 2 detects that the inlet negative pressure reaches -30 kPa, at which point the inlet electric butterfly valve 1 stops. The first-stage compressor enters normal operating condition. The control unit then controls the second return butterfly valve 12 to gradually close until it is completely closed. The outlet butterfly valve 13 of the second-stage compressor begins to close until the third pressure transmitter 10 detects that the pressure reaches 200 kPa, which is fed back to the control unit. The outlet butterfly valve 13 then stops closing, and the second-stage compressor also enters normal operating condition. After 10 minutes of operation, based on feedback from the second temperature transmitter 6 and the fourth temperature transmitter 11, the control unit controls the first spray water ball valve 4 and the second spray water ball valve 8 to adjust their openings, maintaining the compressor temperature at 70°C at the inlet of the first-stage compressor and 120°C at the outlet of the second-stage compressor.

[0059] The intelligent performance testing system for the multi-stage series Roots steam compressor provided in Embodiment 2 of the present invention is used to execute the testing method of Embodiment 1. Therefore, Embodiment 2 of the present invention can achieve the same technical effect as Embodiment 1.

[0060] The description of the relevant parts of the intelligent performance testing system for the multi-stage series Roots steam compressor provided in Embodiment 2 of the present invention can be found in the detailed description of the corresponding parts in the intelligent performance testing method for the multi-stage series Roots steam compressor provided in Embodiment 1 of the present invention, and will not be repeated here.

[0061] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that the elements inherent in a process, method, article, or apparatus that includes a list of elements are included. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. Additionally, portions of the technical solutions provided in the embodiments of the present invention that are consistent with the implementation principles of corresponding technical solutions in the prior art have not been described in detail to avoid excessive elaboration.

[0062] While specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art can make other modifications or variations based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for intelligent performance testing of a multi-stage Roots vapor compressor, characterized in that, The method comprises the following steps: supplying steam as a test medium to a device to be tested; the device to be tested comprises a control unit, a plurality of stages of Roots steam compressors connected in series, an inter-stage spraying device, and a parameter detection unit; controlling, by the control unit, the opening degrees of the valves in the pipeline valve assembly and the spraying water flow rate of the inter-stage spraying device to stabilize the compressors in the device to be tested at preset test working condition points; after the device to be tested is stabilized, collecting, by the parameter detection unit, steady-state operation data within a preset time period, the steady-state operation data at least comprising the inlet and outlet pressures, the inlet and outlet temperatures, and the input power of the compressors; calculating, by using the steady-state operation data, performance evaluation indexes of the device to be tested; the performance evaluation indexes comprising the isentropic efficiency and / or the volumetric efficiency of the compressors.

2. The method of claim 1, wherein, The method further comprises: monitoring the steady-state operation data of the device to be tested in real time, and analyzing, by using a preset fault diagnosis model, the vibration, the temperature change curve, and the parameter change rate; if a fault feature is identified or a parameter exceeds a safety threshold, an automatic protection action is triggered.

3. The method of claim 1, wherein, The control of the opening degrees of the valves in the pipeline valve assembly by the control unit specifically comprises: firstly, gradually closing a first backflow butterfly valve (7) of a first-stage compressor, while adjusting the opening degree of an inlet electric butterfly valve (1) corresponding to the first backflow butterfly valve (7), until the inlet pressure of the first-stage compressor reaches a first-stage design value and is stabilized; then, gradually closing a second backflow butterfly valve (12) of a second-stage compressor, while adjusting the opening degree of the inlet electric butterfly valve (1) corresponding to the second backflow butterfly valve (12), until the outlet pressure of the second-stage compressor reaches a second-stage design value and is stabilized.

4. The method of claim 3, wherein, The control of the spraying water flow rate of the inter-stage spraying device by the control unit to stabilize the compressors in the device to be tested at preset test working condition points specifically comprises: the control unit dynamically adjusts the spraying water flow rate of the corresponding inter-stage spraying device according to the deviation of the outlet temperature of each stage of compressors from a target temperature, to control the outlet temperature of each stage of compressors within a preset temperature range.

5. The method of claim 4, wherein, The dynamic adjustment of the spraying water flow rate of the corresponding inter-stage spraying device specifically comprises: inputting the deviation of the outlet temperature of each stage of compressors from the target temperature into a preset control model, the control model being based on a PID neural network algorithm and obtained by training historical test data; the control model autonomously calculates and learns according to the input deviation, and outputs an optimal control instruction, the optimal control instruction comprising a target spraying water flow rate adjustment amount and a corresponding valve opening degree adjustment amount; the control unit drives the corresponding spraying water regulating valve to perform opening degree adjustment according to the optimal control instruction.

6. The method of claim 1, wherein, The calculation of the performance evaluation indexes of the device to be tested by using the steady-state operation data specifically comprises: isentropic efficiency The calculation process is as follows: Based on the import pressure , export pressure , import temperature and steam property parameters, the isentropic compression work is calculated; the isentropic compression work is subjected to ratio operation with the input power to obtain the isentropic efficiency; ； wherein, is the steam mass flow rate; is the isentropic efficiency; is the steam specific enthalpy found from the inlet pressure and the inlet temperature ; is the steam specific entropy found from the inlet pressure and the inlet temperature ; is the theoretical steam specific enthalpy at an outlet pressure and an entropy value of ; Volume efficiency The calculation process is as follows: The volumetric efficiency is obtained by a ratio operation based on the theoretical discharge volume of the compressor and the actually inhaled steam volume flow rate ; ； wherein is the actual vapor volume flow rate; is the theoretical displacement of the compressor; is the actual vapor volume flow rate; and the inlet temperature the vapor density, is the theoretical displacement of the compressor; is the operating rotational speed of the compressor.

7. The method of claim 1, wherein, the steady-state operation data further comprises the steam mass flow rate flowing through the device to be tested, and the vibration amplitude of each stage of compressors collected by a vibration sensor.

8. The method of claim 2, wherein, The analysis of the vibration, the temperature change curve, and the parameter change rate by using the preset fault diagnosis model specifically comprises: performing time-frequency analysis on the vibration signal to extract vibration features; obtaining temperature instantaneous values, pressure instantaneous values, and flow instantaneous values, and calculating temperature change rates, pressure change rates, and flow change rates; The temperature instantaneous value, pressure instantaneous value and flow instantaneous value are compared with preset safety thresholds in real time, and if any parameter exceeds the corresponding safety threshold range, a primary abnormality flag is generated; The vibration feature, temperature change rate, pressure change rate and flow change rate are collectively input into a preset fault diagnosis model; the fault diagnosis model is a classifier trained based on a machine learning algorithm, used for pattern recognition of the input features and output of confidence corresponding to different fault modes; if the confidence of any fault mode exceeds a preset determination threshold, a secondary abnormality flag is generated and a specific fault type identifier is output.

9. The method of claim 8, wherein, If the fault feature or parameter is identified to exceed the safety threshold, an automatic protection action is triggered; specifically including: If an overpressure anomaly is detected, the bypass valve of the corresponding compressor is controlled to open to a preset opening degree, and if the pressure does not fall within a preset time, the opening degree is further increased; If an overheating anomaly is detected, intensified spraying and backflow are performed; If an abnormal friction is detected, load reduction shutdown is performed; If a surge or stall is detected, emergency shutdown is performed.

10. A test system for carrying out the method of any one of claims 1 to 9, characterized in that Including: a control unit, a multi-stage series Roots vapor compressor, an inter-stage spraying device and a parameter detection unit; the control unit is in communication connection with the multi-stage series Roots vapor compressor, the inter-stage spraying device and the parameter detection unit respectively; The multi-stage series Roots vapor compressor at least includes a series connection of a primary compressor and a secondary compressor; The inter-stage spraying device is arranged between the connecting pipeline of the adjacent two stages of compressors, for spraying atomized water into the compressed steam to control the outlet temperature of the compressor; The parameter detection unit is used for real-time acquisition of working condition data in the test process; at least including: pressure transmitters arranged at the inlets and outlets of the compressors; temperature sensors arranged at the inlets and outlets of the compressors; a mass flow meter arranged on the main steam pipeline; a vibration sensor arranged on the compressor body; The control unit is used for cooperative control of the opening degrees of the valves in the pipeline valve assembly and the spraying water flow of the inter-stage spraying device, so as to stabilize the compressors in the test equipment at preset test working condition points; using the steady-state operation data to calculate performance evaluation indexes of the test equipment; the performance evaluation indexes include isentropic efficiency and / or volumetric efficiency of the compressor.

Images