Modelica-based ship power system virtual-real interaction method

Abstract

The invention provides a ship power system virtual-real interaction method based on Modelica, and relates to the field of ship power systems. The ship power system virtual-real interaction method based on Modelica comprises the following steps: S1, data acquisition: acquiring operation data of a physical entity of a ship power system through a sensor; s2, system model construction: utilizing Modelica language to establish virtual models of the ship power system, wherein the virtual models comprise a generator model, a load model, a grid-connected controller model, a transformer model and the like; and S3, interaction mechanism design: designing a data interaction interface to realize data transmission and synchronization between the physical entity and the virtual model. According to the method, the difficulty and complexity of system model construction are greatly reduced, the modeling workload is reduced, errors caused when a solving sequence is manually specified are also avoided, the reusability, expandability, flexibility and knowledge accumulation capability of the model are remarkably improved, and the test efficiency and reliability of the ship power system can be remarkably improved.

Description

Technical Field

[0001] The present invention relates to the field of ship power systems, and in particular to a virtual-reality interaction method of a ship power system based on Modelica. Background Art

[0002] As an important part of the ship, the stability and reliability of the ship's power system are crucial to the safe navigation of the ship. With the continuous improvement of the degree of ship automation, the performance requirements of the ship's power system are getting higher and higher. The traditional design and testing methods of ship power systems have problems such as low efficiency, high cost, and difficulty in accurately simulating complex working conditions. In the testing stage, the power system usually builds a physical bench for physical testing, but the number of sensors arranged on the physical bench is limited, and it is often impossible to fully monitor the operating status of the system. Therefore, a digital model is used to connect with the physical object in real time, and the virtual and real synchronous simulation is performed by injecting the physical part of the operating data into the model. The model simulation results can fully reflect the operating status of the physical object. At the same time, based on the digital model, virtual working condition simulation can be performed before the experiment begins, and important working conditions can be identified, which greatly reduces the cycle and test cost of the physical test; in the actual ship operation and maintenance stage, due to the strong independence of the power system, any component failure in the system may affect the entire ship power supply network. If a safety hazard occurs during operation, it may even threaten the safety of the entire ship.

[0003] Therefore, in the operation and maintenance process, the use of digital models can fully reflect the operating status of the actual ship through virtual-reality fusion simulation. By comparing the virtual and real operating data, the operating status parameters of the ship can be monitored and interpreted, and potential faults can be eliminated in the early stages of the occurrence of faults. After the fault occurs, the digital twin fault model simulation method can also be used to quickly locate and troubleshoot the fault. Summary of the invention

[0004] 1. Technical issues to be solved

[0005] In view of the deficiencies in the prior art, the present invention provides a virtual-reality interaction method for a ship power system based on Modelica. The non-causal characteristics of the Modelica language make it unnecessary to decouple the thermal control system during the simulation process, and there is no need to specify the input and output variables of the model and the order of solving equations. When solving the equations, the simulation system will determine the order of solving the equations according to the data flow environment of the equation system, which effectively reduces the difficulty and complexity of building the system model and improves the reusability and scalability of the model.

[0006] (II) Technical solution

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: a virtual-real interaction method for a ship power system based on Modelica, the method steps of the virtual-real interaction method for a ship power system based on Modelica are:

[0008] S1: Data collection: collect the operation data of the physical entity of the ship power system through sensors;

[0009] S2: System model construction: Use Modelica language to build a virtual model of the ship power system, including generator model, load model, grid controller model, transformer model, etc.;

[0010] S3: Interaction mechanism design: Design data interaction interface to realize data transmission and synchronization between physical entity and virtual model;

[0011] S4: Data synchronization: Develop a data synchronization mechanism to ensure that the state of the virtual model is consistent with the state of the actual system;

[0012] S5: Auxiliary control instruction generation: Based on the analysis results of the model, control instructions are generated to optimize the performance of the physical system.

[0013] Preferably, in the data collection step of the virtual-reality interaction method for a ship power system based on Modelica, the scope of data collection mainly includes parameters of the voltage, current and rotation speed at the output terminal of the generator.

[0014] Preferably, in the system model building step of the virtual-reality interaction method for the ship power system based on Modelica, the model built includes a generator model, a load model, a grid-connected controller model, and a transformer model.

[0015] Preferably, in the interaction mechanism design step of the Modelica-based ship power system virtual-reality interaction method, the interaction interface adopts the UDP communication protocol, intercepts the network packets of the physical system monitoring system through the network packet analysis software, displays the network packet data as detailed as possible, unpacks, parses and obtains the online measured data according to the specified measured data encapsulation format, receives the online measured data through the developed interface module, and performs data storage and management on the online data.

[0016] Preferably, in the data synchronization step of the virtual-reality interaction method of the ship power system based on Modelica, data synchronization needs to be combined with the test input data of the physical system, and the system simulation model is simulated and calculated and analyzed in a single-step solution mode. The simulation model and the measured data time data are detected in each simulation step, and the simulation rate can be accelerated or slowed down based on the time data to realize the virtual-reality data synchronization function, so as to synchronize the simulation model solution speed with the physical system test time.

[0017] Preferably, in the auxiliary control instruction generation step of the virtual-reality interaction method of the ship power system based on Modelica, the functions of the instructions include but are not limited to adjusting parameters, changing operation modes, etc. The present invention intends to simulate the failure of the main generator on a large ship. The system model detects that the main generator is generating abnormal power. The judgment process is that when the simulation model detects that there is no voltage on the generator bus, it is judged that the generator set fails and trips. The system model automatically generates an instruction to start the standby generator as an auxiliary strategy of the power system, and the output is output with the relationship of or with the actual decision instruction export.

[0018] (III) Beneficial effects

[0019] The present invention provides a virtual-real interaction method for a ship power system based on Modelica, which has the following beneficial effects:

[0020] The invention provides a virtual-reality interaction method for a ship power system based on Modelica. A Modelica language simulation model is solved based on a group of equations. During the solution process, it is not necessary to decouple the system and specify component input and output and the sequence of solving equations. The difficulty and complexity of system model construction are greatly reduced, the modeling workload is reduced, and errors caused by manually specifying the sequence of solving are avoided. The reusability, scalability, flexibility and knowledge accumulation ability of the model are significantly improved, and the test efficiency and reliability of the ship power system can be significantly improved. Real-time data exchange is performed on the basis of an efficient simulation model, and various complex operating conditions can be simulated more realistically, which is helpful to discover potential design defects, reduce debugging costs, and shorten the research and development cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 The power system model library architecture diagram of the virtual-real interaction method of the ship power system based on Modelica of the present invention;

[0022] Figure 2 A virtual-real interaction flow chart of the virtual-real interaction method of a ship power system based on Modelica of the present invention;

[0023] Figure 3 It is a virtual-real interaction interface workflow diagram of the virtual-real interaction method of the ship power system based on Modelica of the present invention;

[0024] Figure 4 This is a code diagram of an interface configuration file of the virtual-real interaction method of a ship power system based on Modelica of the present invention. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. In the description of this application, it should be noted that the terms used here are only for describing specific implementations, and are not intended to limit the exemplary implementations according to the present application. For ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The techniques, methods and devices known to ordinary technicians in the relevant fields may not be discussed in detail, but where appropriate, the techniques, methods and devices should be regarded as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0026] Embodiment 1:

[0027] like Figure 1-4 As shown, an embodiment of the present invention provides a virtual-real interaction method for a ship power system based on Modelica, and the method steps of the virtual-real interaction method for a ship power system based on Modelica are:

[0028] S1: Data collection: collect the operation data of the physical entity of the ship power system through sensors;

[0029] S2: System model construction: Use Modelica language to build a virtual model of the ship power system, including generator model, load model, grid controller model, transformer model, etc.;

[0030] S3: Interaction mechanism design: Design data interaction interface to realize data transmission and synchronization between physical entity and virtual model;

[0031] S4: Data synchronization: Develop a data synchronization mechanism to ensure that the state of the virtual model is consistent with the state of the actual system;

[0032] S5: Auxiliary control instruction generation: Based on the analysis results of the model, control instructions are generated to optimize the performance of the physical system.

[0033] In the data collection step, the scope of data collection mainly includes the parameters of the voltage, current and speed at the output end of the generator;

[0034] In the model building step, the model built includes generator model, load model, grid controller model, and transformer model;

[0035] In the interactive mechanism design step, the interactive interface uses the UDP communication protocol, intercepts the network packets of the physical system monitoring system through the network packet analysis software, displays the network packet data as detailed as possible, unpacks, parses and obtains the online measured data according to the specified measured data encapsulation form, receives the online measured data through the developed interface module, and stores and manages the online data;

[0036] In the data synchronization step, data synchronization needs to be combined with the test input data of the physical system, and the system simulation model is simulated and analyzed in a single-step solution mode. The simulation model and the time data of the measured data are detected in each simulation step. The simulation rate can be accelerated or slowed down based on the time data to realize the virtual and real data synchronization function, and keep the simulation model solution speed synchronized with the physical system test time;

[0037] In the auxiliary control instruction generation step, the functions of the instructions include but are not limited to adjusting parameters, changing operation modes, etc. The present invention intends to simulate the main generator failure on a large ship. The system model detects that the main generator is generating abnormal power. The judgment process is that when the simulation model detects that there is no voltage on the generator bus, it is judged that the generator fault trips. The system model automatically generates an instruction to start the standby generator as an auxiliary strategy of the power system, and the output is output with the relationship of or with the actual decision instruction export.

[0038] Embodiment 2:

[0039] like Figure 1-4 As shown, the embodiment of the present invention provides a virtual-real interaction method of a ship power system based on Modelica. The specific implementation process of the virtual-real interaction of a ship power system based on Modelica mainly includes the following steps:

[0040] Process 1: By installing sensors inside the system, data collection of key electrical parameters, including generator output voltage, output current and speed, is realized and transmitted through the specified data transmission protocol;

[0041] Process 2: Construction of power system model. The power system is modeled according to the standard modeling process of Modelica language. First, the system is divided according to the function of the equipment, including generators, generators, power loads, grid-connected controllers, transformers, etc.; the equipment connector is designed. Through the analysis of the equipment, it can be known that the above power system equipment are all three-phase electrical interfaces. The three-phase electrical interface is created based on the Modelica language. The interface contains two variables, voltage and current. This can ensure that the device interface is freely connected to a non-causal equation and achieve a unified solution; the parameters, variables and equations required for the operation of the equipment are clarified, and the numerical model is implemented using the Modelica language to obtain the equipment model. The equipment model is independently simulated and tested, and the simulation results are compared with the expected theoretical results. If the two are consistent, it means that the component model is verified; if the two are inconsistent, the component model needs to be modified and improved again until the component model meets the requirements; according to the topological structure of the power system, the component models are combined and connected to establish a practical power system model;

[0042] Process 3: Upload measured data: After encapsulating the measured data in the specified format, the UDP protocol (User Datagram Protocol) is used for distribution. The UDP protocol is used to transmit broadcast, multicast and unicast data. In order to overcome the unreliable transmission of the UDP protocol, the important information is confirmed and retransmitted at the application layer after a timeout. Then, the data packet is monitored online through the data receiving model to realize the storage and management of online data, unpack and parse the online measured data, and obtain the measured values. The measured interface information of the power monitoring and the mapping relationship between the measured and simulated parameters are configured through the xml file to realize the comparison and data injection of key parameters of the power system;

[0043] Process 4: Data synchronization implementation: Data synchronization is the key link to ensure accurate interaction and effective collaboration between physical entities and virtual models. Data synchronization is achieved by adding timestamps to simulation results and online measured data packets. In order to ensure the normal operation of virtual-real interaction, the system simulation efficiency must be guaranteed to reach real-time. When the simulation time is ahead of the actual system running time, the solver is paused to wait for the system to run. When the system time is the same as the simulation time, the solver starts real-time simulation. When the simulation time is behind the actual system running time, the solver accelerates the operation to make the simulation rate reach super real-time. When the simulation time catches up with the actual system time, it switches to real-time simulation, thereby achieving the purpose of parallel operation of virtual and real systems.

[0044] Process 5: Downlink of control instructions: For the actual power system, when the main generator set stops or trips for some reason, the standby unit needs to start automatically to carry load. Considering that slow manual operation may lead to long-term shutdown, the stability of the automatic device and the correctness of logic, the power system model can be used for decision verification. By collecting online data, online auxiliary decision-making can be supported. When the power system model detects that the main generator bus is without pressure, it determines that the steam turbine generator set has tripped due to a fault. First, the actual power system is issued an instruction to cut off other loads except the emergency load, and then the standby unit start-up order is issued. After the standby unit starts and builds pressure, it is connected to the grid and loaded. Through this process, the correctness of the logic of the actual power system safety automatic device can be detected. Based on the simulation results of the digital twin model, the control instructions are generated for virtual control, which can greatly improve the adjustment and decision-making efficiency. The actual scene of the control instruction is implemented in the system model. When the system model simulation meets the starting conditions of a certain instruction, the corresponding control instruction signal is issued. The signal is sent through the UDP protocol. After the actual system receives the control signal, it can be used as a reference for system adjustment parameters and operations.

[0045] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A virtual-real interaction method for a ship power system based on Modelica, characterized by: The method steps of the virtual-real interaction method of the ship power system based on Modelica are as follows: S1: Data collection: collect the operation data of the physical entity of the ship power system through sensors; S2: System model construction: Use Modelica language to build a virtual model of the ship power system, including generator model, load model, grid controller model, transformer model, etc.; S3: Interaction mechanism design: Design data interaction interface to realize data transmission and synchronization between physical entity and virtual model; S4: Data synchronization: Develop a data synchronization mechanism to ensure that the state of the virtual model is consistent with the state of the actual system; S5: Auxiliary control instruction generation: Based on the analysis results of the model, control instructions are generated to optimize the performance of the physical system.

2. According to claim 1, a virtual-real interaction method of a ship power system based on Modelica is characterized by: In the data collection step of the virtual-reality interaction method of the ship power system based on Modelica, the scope of data collection mainly includes the parameters of the voltage, current and speed of the generator output terminal.

3. The virtual-real interaction method of a ship power system based on Modelica according to claim 1 is characterized by: In the system model building step of the virtual-reality interaction method of the ship power system based on Modelica, the model built includes a generator model, a load model, a grid-connected controller model, and a transformer model.

4. The virtual-real interaction method of a ship power system based on Modelica according to claim 1, characterized in that: In the interaction mechanism design steps of the virtual-reality interaction method of the ship power system based on Modelica, the interactive interface adopts the UDP communication protocol, and the network packets of the physical system monitoring system are intercepted by the network packet analysis software, and the network packet data is displayed as detailed as possible. According to the specified measured data encapsulation form, the online measured data is unpacked, parsed, and obtained. The online measured data is received through the developed interface module and the online data is stored and managed.

5. The virtual-real interaction method of a ship power system based on Modelica according to claim 1, characterized in that: In the data synchronization step of the virtual-reality interaction method of the ship power system based on Modeli ca, data synchronization needs to be combined with the test input data of the physical system, and the system simulation model is simulated and calculated and analyzed in a single-step solution mode. The time data of the simulation model and the measured data are detected in each simulation step. Based on the time data, the simulation rate can be accelerated or slowed down to realize the virtual-reality data synchronization function, and the simulation model solution speed is synchronized with the physical system test time.

6. The method for virtual-reality interaction of a ship power system based on Modelica according to claim 1, characterized in that: In the auxiliary control instruction generation step of the virtual-reality interaction method of the ship power system based on Modeli ca, the functions of the instructions include but are not limited to adjusting parameters, changing operation modes, etc. The present invention intends to simulate the main generator failure on a large ship. The system model detects that the main generator power generation is abnormal. The judgment process is that when the simulation model detects that the generator set bus has no voltage, it is judged that the generator set fails and trips. The system model automatically generates an instruction to start the backup generator instruction as an auxiliary strategy of the power system, and the output is output in a relationship of or with the actual decision instruction export.

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