Virtual test method for steam turbine unit based on mechanism data cooperation

Abstract

The virtual test method of steam turbine unit based on mechanism data cooperation relates to the technical field of digitalization of ship power system, and the traditional way of obtaining stable operation data of steam power turbine unit has high cost, long cycle and high risk. A simulation model of the steam turbine unit system is constructed; initial operation parameters of different working conditions are input into the simulation model of the steam turbine unit system to make the simulation model run; the rotation speed, thermal power, motor power and steam flow data output by the simulation model at time t are collected, the valve opening at time t+1 is obtained according to the data, and the valve opening at time t+1 is input into the simulation model to control the simulation model to work according to the valve opening at time t+1, and the rotation speed, thermal power, motor power and steam flow data output by the simulation model at time t+1 are output, and the initial value of t is 1; until the multiple valve openings and the simulation model output data within the preset operation time are obtained. The application is used for obtaining the output data.

Description

Technical Field

[0001] The present invention relates to the technical field of digitalization of ship power systems, and pertains to thermal performance analysis and virtual testing of steam-powered steam turbine units. Background Art

[0002] In modern marine propulsion systems, the efficient and reliable operation of steam turbines is crucial for improving ship performance and reducing operating costs. Traditionally, experiments using actual steam turbines have been conducted to obtain data that supports stable operation. However, this existing approach is costly, time-consuming, and can damage the steam turbines, making it a high-risk method. With the advancement of computer simulation technology, virtual testing combined with actual equipment operating data has provided a new solution for optimizing steam turbine performance. Summary of the Invention

[0003] The purpose of the present invention is to solve the problems of high cost, long cycle and high risk in the traditional method of using actual steam-powered steam turbine units for experiments to obtain data that can enable the steam-powered steam turbine units to operate stably. A virtual test method for steam turbine units coordinated with mechanism data is proposed.

[0004] A steam turbine unit virtual test method based on mechanism data collaboration includes the following contents:

[0005] Step 1: Construct a steam turbine model, a condenser model, a vacuum pump model, and a regulating valve model, and integrate all the constructed models into a steam turbine unit system simulation model;

[0006] Step 2: inputting initial operating parameters of different operating conditions into the steam turbine system simulation model to enable the steam turbine system simulation model to operate;

[0007] Step 3: Collect the speed, thermal power, motor power, and steam flow data output by the steam turbine system simulation model at time t, obtain the valve opening at time t+1 based on the data, input the data into the steam turbine system simulation model, control the steam turbine system simulation model to operate according to the valve opening at time t+1, and output the speed, thermal power, motor power, and steam flow data at time t+1, where the initial value of t is 1;

[0008] Step 4: Determine whether the running time between the 1st moment and the tth moment is equal to the preset running time. If so, the steam turbine unit system simulation model stops working, and obtains the corresponding valve opening at each moment during the running time and the corresponding speed, thermal power, motor power and steam flow data output by the steam turbine unit system simulation model. If not, set t=t+1 and execute step 3.

[0009] Preferably, the steam turbine model is constructed in the following manner:

[0010] A steam turbine thermodynamic model is established, and the steam turbine thermodynamic model is constrained using steam flow data, expansion data, and operating parameters to obtain a steam turbine model.

[0011] Preferably, the condenser model is constructed in the following manner:

[0012] A heat exchange model of the condenser is established, and the condenser model is obtained by constraining the heat exchange model of the condenser using the condensation process of water vapor, heat transfer efficiency, cooling water flow and pressure characteristics in the condenser cavity.

[0013] Preferably, the vacuum pump model is constructed in the following manner:

[0014] The ejector model is constructed using the ejector ejection coefficient.

[0015] Preferably, the regulating valve model is constructed in the following manner:

[0016] A flow characteristic model of the control valve is established to simulate the flow characteristics of the control valve at different openings. Combined with the valve resistance characteristic test data, a flow resistance characteristic model of the control valve is established.

[0017] Preferably, in step 3, the electro-hydraulic actuator obtains the valve opening according to the rotational speed, thermal power, motor power and steam flow data.

[0018] Preferably, in step 2, the different operating conditions include dynamic operating conditions and steady-state operating conditions.

[0019] The beneficial effects of the present invention are:

[0020] The present invention constructs a steam turbine unit system simulation model, simulates the operation of the steam turbine unit in a model manner, and obtains the valve opening at the next moment based on the output at the previous moment, thereby controlling the stable operation of the steam turbine unit model and obtaining stable operating data, which is used in a real steam turbine unit to enable the real steam turbine unit to operate stably according to these parameters. Therefore, the simulation model and data-driven model based on physical principles of this application improve the ability to capture the complex dynamic characteristics of the steam turbine unit and enhance the accuracy and timeliness of the simulation results.

[0021] The present invention utilizes a virtual experiment platform to replace physical experiments, significantly reducing equipment wear and failure risks, and lowering material consumption and maintenance costs.

[0022] The present invention adopts a modular design, and the components and functional modules are easy to integrate and expand, adapting to the changing needs of different types of steam turbine units and complex working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is the schematic diagram of the steam turbine unit virtual test system;

[0024] Figure 2Flowchart of the steam turbine unit virtual test method for mechanism data collaboration;

[0025] Figure 3 is a schematic diagram of the steam turbine model;

[0026] Figure 4 This is a schematic diagram of the condenser model;

[0027] Figure 5 This is a schematic diagram of the steam turbine system;

[0028] Figure 6 This is a schematic diagram of data communication between the simulation model and the physical equipment;

[0029] Figure 7 Schematic diagram of the virtual test results of the steam turbine unit. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0031] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0033] Example:

[0034] A steam turbine unit virtual test method based on mechanism data collaboration includes the following contents:

[0035] Step 1: Construct a steam turbine model, a condenser model, a vacuum pump model, and a regulating valve model, and integrate all the constructed models into a steam turbine unit system simulation model;

[0036] Step 2: inputting initial operating parameters of different operating conditions into the steam turbine system simulation model to enable the steam turbine system simulation model to operate;

[0037] Step 3: Collect the speed, thermal power, motor power, and steam flow data output by the steam turbine system simulation model at time t, obtain the valve opening at time t+1 based on the data, input the data into the steam turbine system simulation model, control the steam turbine system simulation model to operate according to the valve opening at time t+1, and output the speed, thermal power, motor power, and steam flow data at time t+1, where the initial value of t is 1;

[0038] Step 4: Determine whether the running time between the 1st moment and the tth moment is equal to the preset running time. If so, the steam turbine unit system simulation model stops working, and obtains the corresponding valve opening at each moment during the running time and the corresponding speed, thermal power, motor power and steam flow data output by the steam turbine unit system simulation model. If not, set t=t+1 and execute step 3.

[0039] Specifically, the steam turbine system simulation model is a fusion model built on the Modelica multi-domain unified modeling and simulation platform. It combines physical simulation with data-driven technologies to ensure the model's accuracy and adaptability, accurately reflecting the actual operating status of the steam turbine unit. Furthermore, the electro-hydraulic actuator controller, as a physical device, ensures the accuracy and reliability of actual device operation. The data acquisition system uses Modbus communication to synchronize data between the simulation model and the physical electro-hydraulic actuator controller, enabling virtual testing of the steam turbine unit's thermal performance, promoting comprehensive improvement and dynamic optimization of the unit's thermal performance.

[0040] Based on the constructed models of key equipment such as steam turbine, condenser, vacuum pump, regulating valve, etc., analyze the system principle topology diagram, clarify the connection relationship, interface type and signal transmission path between each device, and then integrate and debug the simulation model to ensure that the logical connection is carried out according to the topology diagram, and finally obtain the steam turbine unit system simulation model, such as Figure 5 shown.

[0041] Further defining, how the turbine model is constructed:

[0042] A steam turbine thermodynamic model is established, and the steam turbine thermodynamic model is constrained using steam flow data, expansion data, and operating parameters to obtain a steam turbine model.

[0043] Specifically, a thermodynamic model of a multi-stage steam turbine was constructed, using the turbine velocity triangle theory to develop a mechanistic model of steam flow, expansion, and operating parameters (such as flow rate, pressure, and temperature). Leveraging historical operating data, a data proxy model was constructed using a long- and short-term neural network algorithm to supplement aspects that are difficult to model directly physically, such as stage enthalpy drop losses and steam leakage within a multi-stage steam turbine.

[0044] Further definition, the construction method of the condenser model is:

[0045] A heat exchange model of the condenser is established, and the condenser model is obtained by constraining the heat exchange model of the condenser using the condensation process of water vapor, heat transfer efficiency, cooling water flow and pressure characteristics in the condenser cavity.

[0046] Specifically, a condenser heat exchange model was established, combining fluid dynamics and heat conduction equations to simulate the condensation process, heat transfer efficiency, cooling water flow, and pressure characteristics within the condenser cavity. Using experimental data, the condenser's performance was modified and optimized. For example, the simulation model was modified using measured cavity pressure data to improve its accuracy.

[0047] Further defining, how the vacuum pump model is constructed:

[0048] The ejector model is constructed using the ejector ejection coefficient.

[0049] Specifically, the vacuum extractor model mainly uses high-temperature and high-pressure steam to eject steam to achieve the purpose of extracting vacuum. Therefore, the vacuum extractor ejection coefficient proxy model is constructed in combination with the equipment test data.

[0050] Further definition, the construction method of the control valve model is:

[0051] A flow characteristic model of the control valve is established to simulate the flow characteristics of the control valve at different openings. Combined with the valve resistance characteristic test data, a flow resistance characteristic model of the control valve is established.

[0052] Specifically, combined with the valve resistance characteristic test data, the flow rate and pressure drop values ​​at different openings obtained in the experiment are analyzed to establish the valve flow resistance characteristic model. Select an appropriate interpolation or fitting method, such as polynomial fitting, spline interpolation or nonlinear regression, to create a smooth flow resistance curve that captures the relationship between flow rate and pressure drop. In this process, the coefficient of determination (R 2 The goodness of fit of the model is evaluated by statistical indicators such as error (value) and residual analysis to ensure that the established model not only accurately reflects the flow characteristics of the valve under typical operating conditions, but is also suitable for calculation and simulation under different working conditions.

[0053] It is further defined that in step 3, the electro-hydraulic actuator obtains the valve opening according to the speed, thermal power, motor power and steam flow data.

[0054] Specifically, the response speed of the electro-hydraulic actuator is adjusted according to the requirements of different working conditions to ensure its rapid response and stability under full load, partial load and start-stop conditions.

[0055] High-precision sensors are configured at key positions of the electro-hydraulic actuator controller, and different data collection frequencies are set according to the requirements of different working conditions to ensure the authenticity and accuracy of the data.

[0056] Based on the specific requirements of full-load, partial-load, and start-stop operating conditions, select an electro-hydraulic actuator controller with high response speed and high stability to ensure it can adapt to different operating conditions. After the physical equipment is installed, conduct multi-condition testing to verify the actuator's performance in terms of fast response and stability. Record and analyze relevant data to ensure compliance with design requirements.

[0057] High-precision sensors, including pressure, temperature, displacement, and flow, are installed at key locations on the electro-hydraulic actuator controller. When selecting sensors, ensure they meet required accuracy. Suitable data acquisition cards are used to transmit sensor data in real time to a data storage server via high-speed data transmission channels. After system integration, comprehensive testing verifies the interoperability of the sensors and data acquisition card to ensure data authenticity and reliability, providing a foundation for subsequent system optimization.

[0058] According to the on-site network environment and the support of data acquisition equipment, the domestic data acquisition equipment uses the ModbusRTU protocol. However, considering that Modbus TCP is given priority in the wired network environment to improve the data transmission speed and stability, the intermediate gateway is used to convert the Modbus RTU protocol to the Modbus TCP protocol, and the simulation data is transmitted in the form of IEEE754, such as Figure 6 Detailed data mapping relationships between the simulation model and the real-time data acquisition system were defined to ensure accurate mapping of key parameters (such as turbine speed, flow rate, and pressure) between the simulation model and the data acquisition system. Based on the turbine unit's operating characteristics and simulation requirements, the real-time data synchronization update frequency was set to ensure the simulation model could promptly reflect the equipment's real-time status.

[0059] It is further defined that in step 2, different operating conditions include dynamic operating conditions and steady-state operating conditions.

[0060] Specifically, virtual testing of steam turbine units focuses on steady-state and dynamic operating conditions. Steady-state testing simulates the unit's stable operation at rated or partial load, focusing on analyzing key system parameters such as pressure, flow, power, and efficiency during stable operation. Dynamic testing simulates the unit's dynamic regulation under varying load demands, including load ramp-up and load ramp-down scenarios, focusing on analyzing the system's stability and response speed during dynamic regulation.

[0061] Given the upstream and downstream parameter boundaries of the steam turbine unit model, virtual tests are carried out during the unit startup and power increase process, the stable process under rated load and partial load, and the rapid load increase / decrease process. Finally, the unit speed, thermal power, motor power and steam flow results are obtained as follows: Figure 7 shown.

[0062] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the invention. It should be understood that many modifications may be made to the illustrative embodiments, and that other arrangements may be devised, without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in ways other than those described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be employed in conjunction with other described embodiments.

Claims

1. A steam turbine unit virtual test method based on mechanism data collaboration is characterized by: The method includes the following: Step 1: Construct a steam turbine model, a condenser model, a vacuum pump model, and a regulating valve model, and integrate all the constructed models into a steam turbine unit system simulation model; Step 2: inputting initial operating parameters of different operating conditions into the steam turbine system simulation model to enable the steam turbine system simulation model to operate; Step 3: Collect the speed, thermal power, motor power, and steam flow data output by the steam turbine system simulation model at time t, obtain the valve opening at time t+1 based on the data, input the data into the steam turbine system simulation model, control the steam turbine system simulation model to operate according to the valve opening at time t+1, and output the speed, thermal power, motor power, and steam flow data at time t+1, where the initial value of t is 1; Step 4: Determine whether the running time between the 1st moment and the tth moment is equal to the preset running time. If so, the steam turbine unit system simulation model stops working, and obtains the corresponding valve opening at each moment during the running time and the corresponding speed, thermal power, motor power and steam flow data output by the steam turbine unit system simulation model. If not, set t=t+1 and execute step 3.

2. The steam turbine unit virtual test method with mechanism data collaboration according to claim 1 is characterized in that: How to build the steam turbine model: A steam turbine thermodynamic model is established, and the steam turbine thermodynamic model is constrained using steam flow data, expansion data, and operating parameters to obtain a steam turbine model.

3. The steam turbine unit virtual test method with mechanism data collaboration according to claim 1 is characterized in that: Condenser model construction method: A heat exchange model of the condenser is established, and the condenser model is obtained by constraining the heat exchange model of the condenser using the condensation process of water vapor, heat transfer efficiency, cooling water flow and pressure characteristics in the condenser cavity.

4. The steam turbine unit virtual test method with mechanism data collaboration according to claim 1 is characterized in that: The vacuum pump model is constructed as follows: The ejector model is constructed using the ejector ejection coefficient.

5. The steam turbine unit virtual test method with mechanism data collaboration according to claim 1 is characterized in that: The construction method of the control valve model is as follows: A flow characteristic model of the control valve is established to simulate the flow characteristics of the control valve at different openings. Combined with the valve resistance characteristic test data, a flow resistance characteristic model of the control valve is established.

6. The steam turbine unit virtual test method with mechanism data collaboration according to claim 1 is characterized in that: In step 3, the electro-hydraulic actuator obtains the valve opening according to the speed, thermal power, motor power and steam flow data.

7. The steam turbine unit virtual test method with mechanism data collaboration according to claim 1 is characterized in that: In step 2, different working conditions include dynamic working conditions and steady-state working conditions.

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