Experimental control platform for thermal insulation performance of heat-resistant structures based on PLC technology

Abstract

A PLC-based experimental control platform for the thermal insulation performance of heat-resistant structures includes: a remote computer, a local control console, a switch, a CPU module, a temperature acquisition module, a DC power controller, a temperature isolator, and thermocouples. The remote computer and local control console are connected to the switch, which in turn is connected to the CPU module and the temperature acquisition module. The CPU module is connected to the DC power controller, the temperature acquisition module is connected to the temperature isolator, and the temperature isolator is connected to the thermocouples. This invention can be applied to temperature tracking control of radiative heating under quartz lamp aerodynamic environments, and is of great significance for aerospace aerodynamic thermal environment simulation experimental technology.

Description

Technical Field

[0001] This invention relates to an ultra-high temperature quartz lamp infrared radiation aerodynamic thermal environment experimental control platform, belonging to the field of aerospace aerodynamic thermal experiments. Background Technology

[0002] As the design speed of aircraft increases dramatically, the high-temperature thermal environment generated by aerodynamic heating becomes increasingly severe. The high temperatures generated by aerodynamic heating reduce the strength limits of materials and the load-bearing capacity of aircraft structures, causing thermal deformation of materials, damaging the aerodynamic shape of components, and affecting safe flight. To ensure the safety of high-speed aircraft and confirm whether aircraft materials can withstand the thermal shock and high-temperature thermal stress damage generated during high-speed flight, static and dynamic aerodynamic thermal simulation experiments must be conducted on the materials and structures used in high-speed aircraft.

[0003] Meanwhile, with the continuous development of space technology, spacecraft materials research has become one of the key technologies. When a spacecraft flies at high speed through the atmosphere, its surface temperature can change by tens or even hundreds of degrees per second. The changes in the surface temperature and heat flux fields are extremely drastic throughout the flight. Spacecraft in a heated flight state may also perform highly maneuvering operations such as sudden acceleration, climb, turning, and orbit changes, making the relationship between material and structural strength and temperature, heat flux, load, and time very complex. To accurately simulate the aerodynamic and thermal processes of spacecraft structures during high-speed flight, ground-based static and dynamic aerodynamic and thermal simulation experiments must be conducted on the materials and structures used in the spacecraft.

[0004] Quartz lamp radiant heaters have low thermal inertia and excellent electrical control performance, making them ideal for simulating rapid, transient aerodynamic heating. Furthermore, quartz lamp radiant heaters offer advantages such as high heating power, small size, and the ability to be assembled into heating devices of different sizes and shapes. They are also highly adaptable to experimental specimens with complex shapes, making them an ideal radiant heating source for aerodynamic heating simulation experiments.

[0005] Quartz lamp infrared radiation heating is an important method for thermal protection testing in the aerospace field. This test requires rapid and accurate tracking of heat flow and temperature within a given flow field to ensure the test's reliability. Traditional methods struggle to construct an intelligent and rapid testing platform to meet these data requirements, exhibiting the following limitations.

[0006] 1. It cannot achieve rapid tracking of temperature and heat flow, has time lag, and cannot reach the temperature rise slope within a certain time, thus failing to meet the thermal structure assessment requirements of specific thermal protection tests.

[0007] 2. The tracking accuracy is inaccurate, the overshoot is large, and the consistency is poor, resulting in the experimental data having little reference value. Summary of the Invention

[0008] The technical problem solved by this invention is to overcome the shortcomings of the prior art and provide an experimental control platform for the thermal insulation performance of heat-resistant structures based on PLC technology. The surface temperature of the test piece is collected by thermocouples as the controlled variable of the experimental platform. The feedforward + feedback composite control strategy is used to accurately track the nonlinear thermal environment of the heating rate. This invention can provide research and development and operation experience for building a quartz lamp radiation heating test platform with higher power and larger size, and has important significance for aerodynamic thermal protection testing in the aerospace field.

[0009] The technical solution of this invention is:

[0010] The experimental control platform for the thermal insulation performance of heat-resistant structures based on PLC technology includes: a remote computer, a local control console, a switch, a CPU module, a temperature acquisition module, a DC power controller, a temperature isolator, and thermocouples.

[0011] The remote computer and local console are connected to a switch, the switch is connected to a CPU module and a temperature acquisition module, the CPU module is connected to a DC power controller, and the temperature acquisition module is connected to a temperature isolator, which is connected to a thermocouple.

[0012] Thermocouples are used to collect the surface temperature of heat-resistant material test specimens and convert it into an electrical signal that is transmitted to a temperature isolator.

[0013] The temperature isolator is used to convert the electrical signal sent by the thermocouple into a digital quantity, and then transmit the digital quantity as a feedback controlled quantity to the CPU module through the temperature acquisition module.

[0014] The CPU module receives the feedback controlled quantity forwarded by the temperature acquisition module, and receives the set temperature data from the remote computer or local console as the given value through the switch. Based on the given value and the feedback controlled quantity, the CPU module calculates the power value that the DC power supply needs to output and outputs it to the DC power supply power controller.

[0015] The DC power controller converts the DC power required by the CPU module into a thyristor trigger pulse signal, which is then sent to the external thyristor DC power supply. By adjusting the output power of the external thyristor DC power supply, the temperature of the experimental environment in which the heat-resistant material test specimen is located can be changed.

[0016] Preferably, both the remote computer and the local console are industrial computers with WINCC monitoring and data acquisition software installed inside; the remote computer and the local console generate curves and record tables of the set temperature data through the visual window of the WINCC monitoring and data acquisition software.

[0017] Preferably, the temperature isolator is a thermocouple signal isolator.

[0018] Preferably, the temperature isolator is the TS5751 from Tiantuo Sifang Company.

[0019] Preferably, the CPU module sends the power value that the DC power supply needs to output to the DC power controller via the RS485 interface and the Modbus communication protocol.

[0020] Preferably, the CPU module is a CPU module from the Siemens S7-1500 series PLC.

[0021] Preferably, the switch is connected to the CPU module using industrial Ethernet.

[0022] The advantages of this invention compared to the prior art are:

[0023] 1) The CPU module of this invention calculates the power value that the DC power supply needs to output based on the given value and the feedback controlled variable, which can accurately track the nonlinear thermal environment of the heating rate, and provide the necessary experimental conditions for thermal intensity experiments with high temperature, high heat flux and high impact rate.

[0024] 2) The CPU module of this invention is connected to the temperature acquisition module through the backup board bus. It adopts industrial communication bus technology, which reduces the number of signal-to-electrical conversions, greatly reduces signal distortion and line interference, and improves the accuracy of experimental data. Attached Figure Description

[0025] Figure 1 This is a block diagram of a heat insulation performance test control platform system based on PLC technology in one embodiment of the present invention.

[0026] Figure 2 This is a block diagram of the composite control strategy for the experimental control platform.

[0027] The components in the diagram are labeled as follows: 1. Remote computer, 2. Local control console, 3. Switch, 4. CPU module, 5. Temperature acquisition module, 6. DC power controller, 7. Temperature isolator, 8. Thermocouple. Detailed Implementation

[0028] like Figure 1 As shown in the figure, this invention illustrates the basic structure and control relationships of the experimental control platform. The experimental control platform for the thermal insulation performance of heat-resistant structures based on PLC technology includes: a remote computer 1, a local control console 2, a switch 3, a CPU module 4, a temperature acquisition module 5, a DC power controller 6, a temperature isolator 7, and a thermocouple 8. It is primarily used for constructing experimental control platforms for the thermal insulation performance of heat-resistant structures in the aerospace field.

[0029] Both remote computer 1 and local control console 2 are industrial computers, with WINCC monitoring and data acquisition software installed inside. Remote computer 1 and local control console 2 are connected to switch 3, switch 3 is connected to CPU module 4 and temperature acquisition module 5, CPU module 4 is connected to DC power controller 6, and temperature acquisition module 5 is connected to temperature isolator 7, which is connected to thermocouple 8.

[0030] Thermocouple 8 is used to collect the surface temperature of the heat-resistant material test specimen and convert it into an electrical signal to be transmitted to temperature isolator 7; thermocouple 8 is connected to temperature isolator 7 as a device for collecting the temperature of the test specimen.

[0031] Temperature isolator 7 is a thermocouple signal isolator. It connects thermocouple 8 and temperature acquisition module 5, and is used for signal isolation and conversion. The temperature isolator 7 is the TS5751 from TianTuo Sifang Company.

[0032] Temperature isolator 7 is used to convert the electrical signal sent by thermocouple 8 into a digital quantity, and transmit the digital quantity as a feedback controlled quantity to CPU module 4 through temperature acquisition module 5;

[0033] CPU module 4 receives the set temperature data from remote computer 1 or local control console 2 as a given value. Based on the given value and the feedback controlled variable, CPU module 4 calculates the power value that the DC power supply needs to output and outputs it to DC power supply power controller 6.

[0034] CPU module 4 sends the required output power value of the DC power supply to DC power controller 6 via RS485 interface and Modbus communication protocol.

[0035] The DC power controller 6, as the core of the thyristor DC power control, receives the power value signal from the CPU module 4. The DC power controller 6 converts the power value that the DC power supply needs to output sent by the CPU module 4 into a thyristor trigger pulse signal through PID calculation and sends it to the external thyristor DC power supply. By adjusting the output power of the external thyristor DC power supply, the temperature of the experimental environment in which the heat-resistant material test specimen is located is changed.

[0036] CPU module 4 is a CPU module from Siemens S7-1500 series PLC.

[0037] Switch 3 is connected to CPU module 4 via industrial Ethernet, enabling CPU module 4 to communicate with remote computer 1 and local control console 2.

[0038] Remote computer 1 and local console 2 are used to generate curves and record tables from the set temperature data through the visual window of WINCC software, and at the same time monitor the operation of the experimental platform in real time.

[0039] Temperature acquisition module 5 is an analog input acquisition module for the S7-1500 series PLC.

[0040] CPU module 4 is connected to temperature acquisition module 5 via the backup board bus, and receives the temperature signal converted from analog to digital by temperature acquisition module 5 as feedback controlled variable.

[0041] CPU module 4 receives the set temperature data sent by remote computer 1 or local console 2 as a given value, and uses the temperature signal collected by temperature acquisition module 5 as a feedback controlled variable. Through a control algorithm combining feedforward and feedback, it calculates the power value that the DC power supply needs to output, and sends this value to DC power controller 6 through RS485 interface using Modbus communication protocol, thereby realizing accurate tracking of the nonlinear thermal environment of the heating rate.

[0042] like Figure 2 As shown, Figure 1 In this invention, the remote computer 1, local console 2, and switch 3 act as feedforward controllers, while the CPU module 4 and temperature acquisition module 5 act as feedback controllers. This invention achieves accurate tracking of the quartz lamp infrared radiation aerodynamic nonlinear thermal environment. The set temperature is acquired and input into the PLC, employing a feedforward + feedback composite control method (e.g., ...). Figure 2 (As shown) The power output is calculated and sent to the DC power controller to adjust the output power of the DC power supply, thereby achieving accurate tracking of the nonlinear thermal environment of the heating rate.

[0043] This invention is intelligent. Simply input the set temperature curve into WINCC and set the experimental time. After the experiment starts, the control platform will automatically run with the set parameters and collect and archive key parameters such as temperature, heat flow, current, and voltage in real time. When the set experimental time is reached, it will automatically stop running.

[0044] This invention features visualization, enabling the use of the WINCC screen configuration software to generate curves showing how parameters such as set temperature change over time. The horizontal axis of the curve represents time, and the vertical axis represents the values ​​of each parameter, making the data consistency and comparison of key parameters more intuitive.

[0045] This invention can be applied to temperature tracking control of radiant heating in a quartz lamp pneumatic environment, and includes the following steps:

[0046] Step 1: Install WINCC monitoring and data acquisition software on remote computer 1 and local control console 2. Use the visual window of WINCC software to generate curves and record tables of the set temperature data, and monitor the operation of the experimental platform in real time. The experimental platform uses quartz lamp infrared radiation heating.

[0047] Step 2: Switch 3 is connected to CPU module 4 via industrial Ethernet, receives the temperature control curve set by remote computer 1 or local control console 2, and transmits it to CPU module 4.

[0048] Step 3: The CPU module 4 selects to receive the set temperature data sent by the remote computer 1 or the local console 2 as the given value through the program, and sends it to the CPU module 4 through the switch 3.

[0049] Step 4: Thermocouple 8 collects the surface temperature of the heat-resistant material test specimen and converts it into an electrical signal, which is then transmitted to temperature isolator 7. Temperature isolator 7 converts the converted 4-20mA thermocouple signal into a digital quantity, which is then transmitted as a feedback controlled quantity to CPU module 4 through temperature acquisition module 5.

[0050] Step 5: CPU module 4 uses the temperature signal of the heat-resistant material test specimen acquired by temperature acquisition module 5 as the feedback controlled variable, and then uses a control algorithm combining feedforward and feedback (see...). Figure 2 The CPU module 4, using a composite control strategy, calculates the required output power of the DC power supply and sends this value to the DC power controller 6 via an RS485 interface and Modbus communication protocol, thereby achieving accurate tracking of the nonlinear thermal environment of the heating rate. Specifically, the CPU module 4 is used to calculate the required output power of the DC power supply using the composite control strategy, enabling the DC power controller 6 to quickly track and adjust the power.

[0051] Switch 3 serves as a network expansion device, providing more terminal device interfaces for this local area network.

[0052] Temperature acquisition module 5 is an analog input acquisition module for Siemens S7-1500 series PLCs. It has 8 channels, 16-bit analog-to-digital conversion resolution, and a conversion time in the millisecond range.

[0053] The temperature isolator 7 is a thermocouple signal isolator, specifically the TS5751 purchased from TianTuo Sifang Co., Ltd. The temperature isolator 7 connects the thermocouple 8 and the temperature acquisition module 5, serving as signal isolation and conversion. Through reliable isolation between power supply, input, and output, it effectively solves the field interference problem of the industrial automation control system, ensuring the stable and reliable operation of the system.

[0054] The thermocouple 8, which is used as a device for acquiring the temperature of the test piece, is connected to the temperature isolator 7 and converts the surface temperature of the test piece into an electrical signal.

[0055] This invention enables accurate tracking of nonlinear thermal environments: the set temperature is integrated into the PLC, and a feedforward + feedback composite control method is employed (e.g., ...). Figure 2 The power output is calculated and sent to the DC power controller via RS485 interface to adjust the output power of the DC power supply. This enables accurate tracking of the nonlinear thermal environment of the heating rate, providing the necessary experimental conditions for thermal intensity experiments with high temperature, high heat flux, and high impact rate.

[0056] This invention only requires inputting the set temperature curve into WINCC and setting the experimental time. After the experiment starts, the control platform automatically runs according to the set parameters and collects and archives key parameters such as temperature, heat flow, current, and voltage in real time. When the set experimental time is reached, it automatically stops running.

[0057] This invention uses the WINCC screen configuration software to generate curves that change over time for parameters such as set temperature. The horizontal axis of the curve represents time, and the vertical axis represents the values ​​of each parameter, making the data consistency and comparison of key parameters more intuitive.

[0058] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Any person skilled in the art can make possible variations and modifications to the technical solutions of the present invention using the disclosed methods and techniques without departing from the spirit and scope of the invention. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention, without departing from the content of the technical solutions of the present invention, shall fall within the protection scope of the present invention. Where there is no conflict, the embodiments of this application and the technical features thereof can be combined with each other.

[0059] The contents not described in detail in this specification are common knowledge to those skilled in the art.

Claims

1. A PLC-based experimental control platform for the thermal insulation performance of heat-resistant structures, characterized in that, include: Remote computer (1), local console (2), switch (3), CPU module (4), temperature acquisition module (5), DC power controller (6), temperature isolator (7) and thermocouple (8); The remote computer (1) and the local console (2) are connected to the switch (3), the switch (3) is connected to the CPU module (4) and the temperature acquisition module (5), the CPU module (4) is connected to the DC power controller (6), the temperature acquisition module (5) is connected to the temperature isolator (7), and the temperature isolator (7) is connected to the thermocouple (8). Thermocouple (8) is used to collect the surface temperature of the heat-resistant material test piece and convert it into an electrical signal to be transmitted to the temperature isolator (7); The temperature isolator (7) is used to convert the electrical signal sent by the thermocouple (8) into a digital quantity, and transmit the digital quantity as a feedback controlled quantity to the CPU module (4) through the temperature acquisition module (5); The CPU module (4) receives the feedback controlled quantity forwarded by the temperature acquisition module (5), and receives the set temperature data from the remote computer (1) or local console (2) as the given value through the switch (3). The CPU module (4) calculates the power value that the DC power supply needs to output based on the given value and the feedback controlled quantity, and outputs it to the DC power supply power controller (6). The DC power controller (6) converts the DC power required to be output by the CPU module (4) into a thyristor trigger pulse signal and sends it to the external thyristor DC power supply. By adjusting the output power of the external thyristor DC power supply, the temperature of the experimental environment of the heat-resistant material test specimen is changed.

2. The experimental control platform for the thermal insulation performance of the heat-resistant structure based on PLC technology according to claim 1, characterized in that, Both the remote computer (1) and the local console (2) are industrial computers with WINCC monitoring and data acquisition software installed inside. The remote computer (1) and the local console (2) generate curves and record tables of the set temperature data through the visualization window of the WINCC monitoring and data acquisition software.

3. The experimental control platform for the thermal insulation performance of the heat-resistant structure based on PLC technology according to claim 1, characterized in that, Temperature isolator (7) is a thermocouple signal isolator.

4. The experimental control platform for the thermal insulation performance of the heat-resistant structure based on PLC technology according to claim 3, characterized in that, The temperature isolator (7) selected is the TS5751 from Tiantuo Sifang Company.

5. The experimental control platform for the thermal insulation performance of heat-resistant structures based on PLC technology according to any one of claims 1 to 4, characterized in that, The CPU module (4) sends the power value that the DC power supply needs to output to the DC power controller (6) through the RS485 interface and the Modbus communication protocol.

6. The experimental control platform for the thermal insulation performance of the heat-resistant structure based on PLC technology according to claim 5, characterized in that, The CPU module (4) is selected from the CPU module of Siemens S7-1500 series PLC.

7. The experimental control platform for the thermal insulation performance of the heat-resistant structure based on PLC technology according to claim 6, characterized in that, The switch (3) is connected to the CPU module (4) via industrial Ethernet.

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