Aerospace sensor signal electrical isolation method and system
The proposed system addresses the issues of increased complexity and cost in aerospace sensor isolation by converting physical quantities into digital signals for isolation, ensuring accurate and efficient signal transmission without volume or cost penalties, while maintaining compatibility with traditional systems.
Patent Information
- Application Number
- CN202411311033.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-19
- Publication Date
- 2024-12-20
AI Technical Summary
Existing sensor isolation methods in aerospace increase product complexity, cost, and volume while compromising measurement accuracy due to the use of linear optocouplers and separate power supply isolation, which are not suitable for high-precision measurements.
A system comprising a sensor sensitive signal module, signal conditioning and AD acquisition module, isolation communication module, MCU module, and power circuit module, which converts physical quantities into digital signals for isolation and transmission, eliminating the need for separate DC/DC isolated power supplies and filter circuits.
This system ensures accurate and efficient isolation of sensor signals without increasing volume or cost, maintaining measurement precision and compatibility with traditional systems.
Smart Images
Figure CN119164429A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of rockets, and in particular, to a method and system for electrical isolation of aerospace sensor signals. Background Art
[0002] As the integration of rocket system equipment becomes higher and higher, wireless devices become more and more diversified, and the electromagnetic compatibility environment on rockets becomes more and more complex, the electromagnetic compatibility requirements for sensors, which are small signal products, are also getting higher and higher, especially for liquid propellants such as liquid oxygen, liquid hydrogen, and methane. In addition to the electromagnetic compatibility environment, the problem of sensor insulation resistance reduction caused by low-temperature condensation and other environments must also be considered. Therefore, it is necessary to adopt electrical isolation between the system and the sensor. At present, most sensors isolate the sensor power supply and system power supply through isolation DC / DC chips, and then isolate the sensor output signal through isolation devices such as HCNR200, LOC111, LOC211, IL300, AMC1100, AMC1200, AMC1300 and other linear optocouplers, so that the input and output ends are electrically isolated. In order to isolate the power supply between the on-arrow measurement system and the sensor, an isolated DC / DC is required. The isolated DC / DC generally has a large ripple voltage, and the corresponding power supply filter circuit must be added, which is bound to increase the volume of the product. The input end of the photocoupler is a light-emitting diode, that is, the input characteristic can be represented by the volt-ampere characteristic of the light-emitting diode; the output end is a phototransistor, so the volt-ampere characteristic of the phototransistor is its output characteristic. Therefore, the photocoupler has a nonlinear working area, and the accuracy is poor when it is directly used to isolate and transmit analog quantities. At present, the linear index of the optocoupler can reach 0.075%, but for some high-precision measurement sensors, it has affected the measurement accuracy. In summary, the above scheme not only increases the complexity of the product, resulting in increased costs and volume, but also reduces the measurement accuracy of the sensor; at the same time, the system needs to collect each sensor signal separately, and multiple sensors cannot be collected on the same ground, which increases the engineering measurement of the on-arrow acquisition system.
[0003] Therefore, how to provide a flexible and universal aerospace sensor signal electrical isolation method to solve the problems of increased cost, increased volume and impaired accuracy caused by complete isolation of sensor power supply and signal has become an urgent problem to be solved in this field. Summary of the invention
[0004] The present application proposes an aerospace sensor signal electrical isolation system, which is characterized in that it includes a sensor sensitive signal module, a signal conditioning and AD acquisition module, an isolation communication module, an MCU module and a power circuit module; the sensor sensitive signal module is used to convert the physical quantity on the arrow into a changing electrical quantity; the signal conditioning and AD acquisition module is connected to the sensor sensitive signal module, and is used to convert the changing electrical quantity into a digital signal; the isolation communication module is connected to the signal conditioning and AD acquisition module, and is used to power the signal conditioning and AD modules, and transmit the converted digital signal to the MCU module; the MCU module is connected to the isolation communication module, and is used to perform data processing on the transmitted digital signal and then send it to the on-arrow measurement system; the power circuit module is respectively connected to the isolation communication module, the MCU module and the DA conversion impedance matching module, and is used for the on-arrow measurement system to power the isolation communication module, the MCU module and the DA conversion impedance matching module.
[0005] As mentioned above, the sensor sensitive signal module converts the physical quantity on the arrow into a change in electrical quantity, including converting the change in the physical quantity of heat flow, temperature, pressure, and vibration on the arrow into a change in resistance, voltage, and electrical quantity.
[0006] As above, it also includes a DA conversion impedance matching module; the DA conversion impedance matching module is connected to the MCU module, and is used to match the digital signal transmitted from the MCU and then output an analog signal to send to the on-arrow measurement system.
[0007] As above, there are one or more sensor sensitive signal modules.
[0008] As above, wherein the isolated communication module includes a power supply for providing isolation.
[0009] An aerospace sensor signal electrical isolation system includes the following steps: converting a physical quantity on an arrow into a changing electrical quantity; converting the electrical quantity signal into a digital signal; and transmitting the digital signal to a measurement system on the arrow.
[0010] As above, converting the physical quantity on the arrow into a changing electrical quantity includes converting the changes in the physical quantities of heat flow, temperature, pressure, and vibration on the arrow into changes in resistance and voltage electrical quantity.
[0011] As mentioned above, converting the electric quantity signal into a digital signal includes transforming and filtering the resistance and voltage signals converted from the physical quantity, and converting the signals into digital signals.
[0012] As above, wherein transmitting the digital signal to the on-arrow measurement system includes performing DA conversion on the digital signal and then sending it to the on-arrow measurement system.
[0013] As above, wherein transmitting the digital signal to the on-arrow measurement system includes processing the digital signal and then sending it to the on-arrow measurement system.
[0014] This application has the following beneficial effects:
[0015] This application can simply and conveniently isolate the weak signals of the aerospace sensor from the back-end power supply and signal transmission, effectively reducing the interference of the long-line transmission of the circuit signal. The digital isolation method will not increase the volume of the sensor itself, and can effectively ensure the original measurement accuracy of the sensor. At the same time, it is also compatible with the traditional measurement system solution on the rocket, and will not cause any design changes to the system. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.
[0017] Figure 1 It is a schematic diagram of the internal structure of the aerospace sensor signal electrical isolation system provided according to an embodiment of the present application;
[0018] Figure 2 It is a flow chart of a method for electrical isolation of aerospace sensor signals provided according to an embodiment of the present application. DETAILED DESCRIPTION
[0019] The following is a clear and complete description of the technical solutions in the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.
[0020] The present application provides a method and system for electrical isolation of aerospace sensor signals, which mainly focuses on isolating the power supply to the sensor on the arrow from the power supply of the sensor processing tiny sensitive signals, thereby ensuring that the tiny signal is not affected by the onboard system. There is no need to worry about the same nonlinear problems as linear optocoupler isolation when isolating signals using digital isolation communication. As long as the bandwidth and accuracy of communication are guaranteed, digital isolation can ensure that the sensor measurement accuracy is not lost due to isolation. Generally, the frequency response of vibration and impact sensors is relatively high, up to 10KHz, but the bandwidth of digital isolation communication can reach 1MHz, which is fully capable of meeting the requirements of sensor signal sampling and communication frequency response.
[0021] Embodiment 1
[0022] like Figure 1 As shown, this embodiment provides an aerospace sensor signal electrical isolation system, which specifically includes a sensor sensitive signal module 101, a signal conditioning and AD acquisition module 102, an isolation communication module 103, an MCU module 104, a DA conversion impedance matching module 105, and a power circuit module 106.
[0023] The sensor sensitive signal module 101 is used to convert the physical quantity on the arrow into a changing electrical quantity.
[0024] Specifically, the changes in physical quantities such as heat flow, temperature, pressure, and vibration on the arrow are converted into changes in electrical quantities such as resistance and voltage.
[0025] There can be one or more sensor sensitive signal modules 101. When there is one sensor sensitive signal module 101, it can be used for electrical isolation of a single-channel sensor. When there are multiple sensor sensitive signal modules 101, it can be used for electrical isolation of multiple-channel sensors.
[0026] It is worth noting that the converted resistance, voltage, etc. are tiny sensitive signals that are only easily affected by the sensor.
[0027] The signal conditioning and AD acquisition module 102 is connected to the sensor sensitive signal module 101 and is used to transform and filter tiny sensitive signals such as resistance and voltage converted from physical quantities and convert the signals into digital signals.
[0028] The isolation communication module 103 is connected to the signal conditioning and AD acquisition module 102 and is used to supply power to the signal conditioning and AD acquisition module 102 and transmit the digital signal converted by the signal conditioning and AD acquisition module 102 to the MCU module 104 .
[0029] The isolated communication module 103 mainly realizes two functions: one is to isolate and output its own power supply to the front-end signal conditioning and AD module power supply, and the other is to isolate and transmit the digital signal converted by AD to the back-end MCU processing circuit, realizing the isolation of the tiny signal at the front end of the sensor and the back-end circuit.
[0030] The isolated communication module 103 in this embodiment is specifically a digital isolated communication module, which can provide an isolated power supply in a single module, eliminating the need for a separate DC / DC isolated power supply and filter circuit, and will not affect the product volume and cost. As well as the isolated signal channel, there is no loss in sensor signal accuracy, and the isolated transmission bandwidth is as high as 1MHz, which fully meets the sensor signal response speed and frequency response index requirements.
[0031] The MCU module 104 is connected to the isolation communication module 103, and is used to process the transmitted digital signal and send it to the on-arrow measurement system, or to match the transmitted digital signal through the DA conversion impedance matching module 105 and then output an analog signal to send it to the on-arrow measurement system.
[0032] The data processing specifically includes that the MCU module 104 amplifies, samples, and performs least square filtering on the isolated digital signal and converts it into a directly readable sensor digital signal according to the proportional relationship between electrical quantity and physical quantity, so as to facilitate the on-arrow measurement system to detect physical parameters.
[0033] If the arrow needs to collect data uniformly according to analog quantities, a low impedance output is required for the collected signal, so a DA conversion impedance matching module 105 is required to perform impedance matching after DA conversion, and then provide it to the arrow measurement system for signal collection.
[0034] The power circuit module 106 is respectively connected to the isolated communication module 103 , the MCU module 104 and the DA conversion impedance matching module 105 , and is used for the on-arrow measurement system to supply power to the isolated communication module 103 , the MCU module 104 and the DA conversion impedance matching module 105 .
[0035] The on-arrow measurement system can share the same power ground for power supply and output collection, which will not increase the engineering workload of the on-arrow collection system.
[0036] Embodiment 2
[0037] This embodiment provides an aerospace sensor signal electrical isolation method based on an aerospace sensor signal electrical isolation system, which specifically includes the following steps:
[0038] Step S210: Convert the physical quantity on the arrow into a changing electrical quantity.
[0039] Specifically, the changes in physical quantities such as heat flow, temperature, pressure, and vibration on the arrow are converted into changes in electrical quantities such as resistance and voltage.
[0040] Step S220: Convert the electric quantity signal into a digital signal.
[0041] The tiny signals such as resistance and voltage converted from physical quantities are transformed and filtered, and then converted into digital signals.
[0042] Step S230: isolating the digital signal and transmitting it to the on-arrow measurement system.
[0043] Specifically, isolating the digital signal and transmitting it to the onboard measurement system includes:
[0044] Isolate digital signals.
[0045] The isolated digital signal is transmitted to the on-arrow measurement system through the MCU circuit.
[0046] There are two ways to transmit digital signals to the on-arrow measurement system. One is that the MCU circuit processes the digital signals and sends them to the on-arrow measurement system. The other is that the MCU circuit performs DA conversion impedance matching on the transmitted digital signals and then outputs analog signals to the on-arrow measurement system.
[0047] The MCU circuit is a circuit structure in the prior art and will not be described in detail.
[0048] This application has the following beneficial effects:
[0049] This application can simply and conveniently isolate the weak signals of the aerospace sensor from the back-end power supply and signal transmission, effectively reducing the interference of the long-line transmission of the circuit signal. The digital isolation method will not increase the volume of the sensor itself, and can effectively ensure the original measurement accuracy of the sensor. At the same time, it is also compatible with the traditional measurement system solution on the rocket, and will not cause any design changes to the system.
[0050] Although the present application is described with reference to examples, this is for illustrative purposes only and is not intended to limit the present application, and changes, additions and / or deletions to the embodiments may be made without departing from the scope of the present application.
[0051] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.
Claims
1. An aerospace sensor signal electrical isolation system, characterized in that: It includes sensor sensitive signal module, signal conditioning and AD acquisition module, isolation communication module, MCU module and power circuit module; The sensor sensitive signal module is used to convert the physical quantity on the arrow into the changing electrical quantity; The signal conditioning and AD acquisition module is connected to the sensor sensitive signal module to convert the changing electrical quantity into a digital signal; The isolation communication module is connected to the signal conditioning and AD acquisition module to supply power to the signal conditioning and AD modules and transmit the converted digital signals to the MCU module; The MCU module is connected to the isolated communication module and is used to process the transmitted digital signal and send it to the on-arrow measurement system; The power circuit module is respectively connected to the isolation communication module, the MCU module and the DA conversion impedance matching module, and is used for the on-arrow measurement system to power the isolation communication module, the MCU module and the DA conversion impedance matching module.
2. The aerospace sensor signal electrical isolation system according to claim 1, characterized in that: The sensor sensitive signal module converts the physical quantity on the arrow into the changing electrical quantity, including converting the changes of the physical quantity of heat flow, temperature, pressure and vibration on the arrow into the changes of resistance and voltage.
3. The aerospace sensor signal electrical isolation system according to claim 1, characterized in that: Also includes, DA conversion impedance matching module; The DA conversion impedance matching module is connected to the MCU module and is used to match the digital signal transmitted from the MCU and then output the analog signal to send to the on-arrow measurement system.
4. The aerospace sensor signal electrical isolation system according to claim 1, characterized in that: The sensor sensitive signal module is one or more.
5. The aerospace sensor signal electrical isolation system according to claim 1, characterized in that: The isolated communication module includes a power supply to provide isolation.
6. An aerospace sensor signal electrical isolation system, characterized in that: The following steps are involved: Convert the physical quantity on the arrow into a changing electrical quantity; Convert the electric quantity signal into a digital signal; Transmit digital signal to the on-arrow measurement system.
7. The aerospace sensor signal electrical isolation system according to claim 6, characterized in that: Converting the physical quantity on the arrow into changing electrical quantity includes converting the changes in the physical quantities of heat flow, temperature, pressure, and vibration on the arrow into changes in resistance, voltage, and electrical quantity.
8. The aerospace sensor signal electrical isolation system according to claim 6, characterized in that: Converting the electric quantity signal into a digital signal includes transforming and filtering the resistance and voltage signals converted from the physical quantity, and converting the signals into digital signals.
9. The aerospace sensor signal electrical isolation system according to claim 6, characterized in that: Transmitting digital signals to the onboard measurement system includes, The digital signal is converted into impedance through DA and then sent to the on-arrow measurement system.
10. The aerospace sensor signal electrical isolation system according to claim 6, characterized in that: Transmitting digital signals to the onboard measurement system includes, After the digital signal is processed, it is sent to the on-arrow measurement system.