Vacuum synchronism measurement system, method and control method for sperf devices

Abstract

The vacuum synchronism measurement system, method and control method of the SPERF device relate to the technical field of space plasma environment simulation.The present application is to solve the problem that the time delay from the inflation start to the vacuum meeting the condition cannot be accurately measured when the existing SPERF device is experimented, and the experimental requirements are not met.The present application provides a vacuum synchronism measurement system, method and control method suitable for the SPERF device, which can measure the high synchronism of the inflation system and the vacuum gauge measurement value, according to the inflation system and the vacuum gauge characteristics, the vacuum curve requirements meeting the experimental requirements are given, and the control method of the vacuum pressure and the vacuum curve meeting the experimental requirements is provided.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of space plasma environment simulation. BACKGROUND

[0002] The working mode of the near-earth space plasma environment simulation cabin in the SPERF device (space plasma environment simulation and research device) is a prepared and triggered burst mode, which requires an effective experiment time less than or equal to 100 ms, and the synchronization of each sub-device is also very high. The vacuum pressure of the working medium gas in the vacuum tank is an important parameter of the plasma experiment, which is related to the success or failure of the experiment, so a special device is needed to adjust the vacuum pressure of the working medium gas in the vacuum tank. The vacuum control system is an important part of the near-earth space plasma environment simulation cabin, which can provide the required vacuum working environment for the near-earth space plasma environment simulation cabin.

[0003] As shown in Figure 1 The vacuum control system reads the vacuum value from the three cold rules through the RS485 communication mode, and the scanning period is 500 ms. At the same time, the vacuum control system also controls the vacuum acquisition device to extract the gas in the vacuum tank through the DP communication mode to maintain the vacuum state of the vacuum tank. The inflation system is composed of a driver and eight piezoelectric ceramic valves, and the inflation system is used to inflate the working medium gas (hydrogen H2) into the vacuum tank. The driver supplies power to the piezoelectric ceramic valve through the coaxial line to control the opening and closing of the piezoelectric ceramic valve. The timing synchronization system triggers the driver through the trigger optical fiber, thereby controlling the opening time and closing time of the piezoelectric ceramic valve. The timing synchronization system, the vacuum control system and the inflation system driver respectively perform data interaction with the central control system in the form of TCP / IP communication, OPC communication and RS422 communication, receive the centralized control of the central control system, and the data interaction period is 1s.

[0004] In the process of the experiment of the SPERF device, in order to ensure the concentration and pressure of the working medium gas, the vacuum tank pressure control adopts the mode of extracting and inflating at the same time, that is, the vacuum control system controls the vacuum acquisition device to extract the gas in the vacuum tank, and continuously extracts the leaked air, when the pressure in the vacuum tank is reduced to 1e-4Pa, the inflation system inflates the working medium gas into the vacuum tank to maintain the concentration and pressure of the working medium gas in a short time. And it is required that during the experiment, when the vacuum pressure is in the range of 9.9e-2Pa to 1e-2Pa, the experiment is started after the vacuum environment meets the requirements, and the experiment duration is not greater than 100 ms.

[0005] The inflation system is triggered by a timing synchronization system, and works in high synchronization (with a time deviation of less than 1 us) with other devices of the near-earth space plasma environment simulation cabin. However, the inflation system data and the vacuum gauge measurement data are collected in the central control system, and the data collection period is 1 s, so the synchronization of the inflation system data and the vacuum gauge measurement data is greater than 1 s, and the time delay from the start of inflation to the time when the vacuum meets the condition cannot be accurately measured, which cannot meet the experimental requirements. SUMMARY

[0006] The present application is to solve the problem that the time delay from the start of inflation to the time when the vacuum meets the condition cannot be accurately measured in the existing SPERF device experiment, which cannot meet the experimental requirements. The present application provides a vacuum synchronization measurement system, method and control method of a SPERF device.

[0007] The vacuum synchronization measurement method of the SPERF device specifically comprises:

[0008] A reference optical fiber with the same trigger time and pulse width as a trigger optical fiber is connected to a timing synchronization system of the SPERF device, and the trigger optical fiber is an optical fiber through which the timing synchronization system outputs a trigger signal to an inflation system of the SPERF device;

[0009] The time T0 of the rising edge of the trigger signal is collected through the reference optical fiber;

[0010] An analog voltage signal collected by an i-th vacuum gauge of the SPERF device during j-th experiment is collected, and the time T ij when the analog voltage signal reaches an experimental pressure P0 is recorded, i = 1, 2,..., I, I is the number of vacuum gauges in the SPERF device, and j ≥ 5;

[0011] The time interval ΔT ij between T0 and T ij is calculated, and the absolute value of the difference between the two time intervals is calculated.

[0012] The maximum absolute value is selected as the time jitter T from the rising edge of the trigger signal to the time when the vacuum gauge measurement value reaches the experimental pressure P0.

[0013] The vacuum synchronization measurement system of the SPERF device comprises a collection unit, a timing unit, a calculation unit and a measurement unit,

[0014] The timing synchronization system of the SPERF device is connected to a reference optical fiber with the same trigger time and pulse width as a trigger optical fiber, the reference optical fiber is connected to a trigger signal input end of the collection unit, so that the collection unit can receive the trigger signal at the same time as the inflation system of the SPERF device, and the trigger optical fiber is an optical fiber through which the timing synchronization system outputs a trigger signal to an inflation system of the SPERF device.

[0015] The analog voltage signal output end of the vacuum gauge in the SPERF device is connected to the analog voltage signal input end of the acquisition unit;

[0016] The timing unit is used to record the time T0 when the rising edge of the trigger signal is received by the acquisition unit, and the time T ij , i = 1, 2,..., I, I is the number of vacuum gauges in the SPERF device, and j ≥ 5;

[0017] The calculation unit is used to calculate the time interval ΔT ij between T0 and T ij , and the absolute value of the difference between the two time intervals,

[0018] The measurement unit is used to select the maximum absolute value as the time jitter T from the rising edge of the trigger signal to the measurement value of the vacuum gauge reaching the experimental pressure P0.

[0019] The control method of the SPERF device, specifically:

[0020] The time jitter T is measured by using the above-mentioned vacuum synchronization measurement method of the SPERF device;

[0021] By adjusting the threshold voltage of the driver in the SPERF device to control the opening valve position of the piezoelectric ceramic valve, until Δt BA > T + t, wherein Δt BA is the time interval from the vacuum pressure measurement value of the vacuum tank of the SPERF device rising from 80% P0 to P0 during the inflation process, t is the measurement reaction time of the vacuum gauge in the SPERF device, and P0 is the experimental pressure;

[0022] By adjusting the pulse width of the trigger signal to adjust the pulse width of the piezoelectric ceramic valve, until the vacuum pressure measurement peak value reaches P0,

[0023] By adjusting the vacuum control system of the SPERF device to adjust the pumping rate of the vacuum acquisition equipment, until Δt AC > T + t, wherein Δt AC is the time interval from the vacuum pressure measurement value of the vacuum tank of the SPERF device falling from P0 to 80% P0 after the inflation is completed.

[0024] Further, the above-mentioned experimental pressure P0 is between 9.9e-7 Pa and 1e-2 Pa.

[0025] Further, the voltage range of the analog voltage signal of the vacuum gauge in the above-mentioned SPERF device is 0V-10V.

[0026] Further, the reference optical fiber is connected to the acquisition unit through an optical-electricity converter.

[0027] Further, t=50 ms. The present application has the following effects: the present application can measure the high synchronization of the inflation system and the vacuum gauge measurement value, and provide a vacuum working environment meeting the experimental requirements.

[0028] The present application provides a vacuum synchronization measurement system, method and control method suitable for SPERF devices, which can measure the high synchronization of the inflation system and the vacuum gauge measurement value, and provide a vacuum curve requirement meeting the experimental requirements according to the characteristics of the inflation system and the vacuum gauge, and a control method meeting the experimental requirements of the vacuum pressure and the vacuum curve. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 It is a working schematic diagram of the inflation system and the vacuum control system in the existing SPERF device.

[0030] Figure 2 It is a structural schematic diagram of the vacuum synchronization measurement system of the SPERF device.

[0031] Figure 3 It is an experimental pressure requirement schematic diagram. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application. It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0033] Specific implementation method one: reference Figure 2 Specifically, the vacuum synchronization measurement method of the SPERF device in the present embodiment is as follows:

[0034] A reference optical fiber with the same trigger time and pulse width as the trigger optical fiber is connected to the timing synchronization system of the SPERF device, and the trigger optical fiber is an optical fiber through which the timing synchronization system outputs a trigger signal to the inflation system of the SPERF device.

[0035] The time T0 of the rising edge of the trigger signal is acquired through the reference optical fiber.

[0036] The analog voltage signal collected by the i-th vacuum gauge of the SPERF device during the j-th experiment is collected, and the time T at which the analog voltage signal reaches the experimental pressure P0 is recorded ij , i = 1, 2, 3, j ≥ 5.

[0037] The time interval ΔT between T0 and T ij is calculated ij , and the absolute value of the difference between ΔT ij and the remaining (3j-1) time intervals is calculated.

[0038] The maximum absolute value is selected as the trigger signal rising edge to the time jitter T of the vacuum gauge measurement value reaching the experimental pressure P0.

[0039] Wherein, the experimental pressure P0 is between 9.9e-7Pa and 1e-2Pa, and the voltage range of the analog voltage signal of the vacuum gauge in the SPERF device is 0V-10V.

[0040] Specific implementation method two: refer to Figure 2 The SPERF device of the present embodiment has a vacuum synchronous measurement system, which comprises a collection unit, a timing unit, a calculation unit and a measurement unit. The sampling rate of the collection unit is 1M / s, the sampling channel is 12, and the input voltage range is 0V-100V.

[0041] In this embodiment, the three vacuum gauges of the SPERF device have analog output ports, which can connect the analog voltage signal to the analog voltage signal input end of the collection unit. The vacuum gauge can realize the non-delay of the vacuum gauge measurement value to the collection system through the analog output mode.

[0042] The timing synchronization system of the SPERF device is connected to a reference optical fiber with the same trigger time and pulse width as the trigger optical fiber, and the reference optical fiber is connected to the trigger signal input end of the collection unit through an optical-electric converter, so that the collection unit can receive the trigger signal at the same time as the charging system of the SPERF device. The output voltage of the driver controls the piezoelectric ceramic valve switch to charge the working gas into the vacuum tank, and the trigger optical fiber is the optical fiber that outputs the trigger signal from the timing synchronization system to the charging system of the SPERF device.

[0043] The timing unit is used to record the time T0 at which the collection unit receives the rising edge of the trigger signal, and the time T ij at which the analog voltage signal collected by the i-th vacuum gauge of the SPERF device during the j-th experiment reaches the experimental pressure P0, i = 1, 2, 3, j ≥ 5.

[0044] The calculation unit is used to calculate the time interval ΔT between T0 and T ij ​ij and calculate AT ij the absolute value of the difference from the rest (3j-1) time intervals.

[0045] The measurement unit is used to select the maximum absolute value as the rising edge of the trigger signal to the time jitter T of the time when the vacuum gauge measurement value reaches the experimental pressure P0.

[0046] Wherein, the experimental pressure P0 is between 9.9e-7Pa and 1e-2Pa, and the voltage range of the analog voltage signal of the vacuum gauge in the SPERF device is 0V-10V.

[0047] Specific implementation three: reference Figure 3 Specifically, the control method of the SPERF device described in this embodiment, considering the measurement reaction time t=50ms of the vacuum gauge, the precision range is 20%, so as to meet the experimental demand of the vacuum curve of the vacuum pressure, as shown in Figure 3 The timing synchronization system starts to inflate at point D, and ends to inflate at point E; point A is the peak value P0 of the vacuum pressure measurement (experimental pressure); during the inflation process, the vacuum pressure measurement value reaches 80% P0 at point B; After the inflation is over, the vacuum pressure measurement value reaches 80% P0 at point C.

[0048] The time jitter T is measured by using the vacuum synchronization measurement method of the SPERF device described in the above embodiment one.

[0049] By adjusting the threshold voltage of the driver in the SPERF device to control the opening valve position of the piezoelectric ceramic valve, until Δt BA >T+t, wherein Δt BA is the time interval of the vacuum pressure measurement value of the vacuum tank of the SPERF device from 80% P0 to P0 during the inflation process, and t is the measurement reaction time of the vacuum gauge in the SPERF device.

[0050] By adjusting the pulse width of the trigger signal to adjust the pulse width of the piezoelectric ceramic valve, until the peak value of the vacuum pressure measurement reaches P0.

[0051] By adjusting the vacuum control system of the SPERF device to adjust the pumping rate of the vacuum acquisition equipment, until Δt AC >T+t, wherein Δt AC is the time interval of the vacuum pressure measurement value of the vacuum tank of the SPERF device from P0 to 80% P0 after the inflation is over.

[0052] While the application has been described with reference to particular embodiments thereof, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present application. It will be apparent to those skilled in the art that numerous modifications can be made within the scope of the present application as defined by the appended claims. It is intended that all such modification fall within the spirit and scope of the present application. It will be understood that the features described in connection with one embodiment can be used in connection with another embodiment.

Claims

1. A method for measuring the vacuum synchronicity of a SPERF device, characterized in that, a reference optical fiber with the same trigger time and pulse width as a trigger optical fiber is connected to a timing synchronization system of the SPERF device, the trigger optical fiber being an optical fiber through which the timing synchronization system outputs a trigger signal to a gas filling system of the SPERF device; the time T0 of the rising edge of the trigger signal is collected through the reference optical fiber; Collecting the analog voltage signal collected by the i th vacuum gauge in the j th experiment of the SPERF device, and recording the time T when the analog voltage signal reaches the experimental pressure P0 ij , i = 1, 2,..., I, I is the number of vacuum gauges in the SPERF device, j ≥ 5; The time intervals ΔT between T0 and T ij are calculated ij and the absolute values of the differences between the time intervals two by two. the maximum absolute value is selected as the time jitter T of the rising edge of the trigger signal to the time when the vacuum gauge measurement value reaches the experimental pressure P0. 2.The method for measuring the vacuum synchronicity of the SPERF device according to claim 1, characterized in that, the experimental pressure P0 is between 9.9e-7 Pa and 1e-2 Pa.

3. The method of claim 1 or 2, wherein the method is performed by the SPERF device. The voltage range of the analog voltage signal of the vacuum gauge in the SPERF device is 0V-10V.

4. A vacuum synchronism measurement system of a SPERF device, characterized by The vacuum synchronicity measurement system comprises a collection unit, a timing unit, a calculation unit, and a measurement unit, the timing synchronization system of the SPERF device is connected to a reference optical fiber with the same trigger time and pulse width as a trigger optical fiber, the reference optical fiber is connected to the trigger signal input end of the collection unit, so that the collection unit can simultaneously receive the trigger signal from the gas filling system of the SPERF device, and the trigger optical fiber is an optical fiber through which the timing synchronization system outputs a trigger signal to the gas filling system of the SPERF device; the analog voltage signal output end of the vacuum gauge in the SPERF device is connected to the analog voltage signal input end of the collection unit; The timing unit is used for recording the time T0 when the rising edge of the trigger signal received by the acquisition unit and the time T when the analog voltage signal collected by the i-th vacuum gauge of the SPERF device reaches the experimental pressure P0 during the j-th experiment ij , i = 1, 2,..., I, I is the number of vacuum gauges in the SPERF device, and j ≥ 5; The computing unit is configured to calculate the time interval ΔT ij between T0 and T ij and the absolute value of the difference between the two time intervals, respectively. the measurement unit is used to select the maximum absolute value as the time jitter T of the rising edge of the trigger signal to the time when the vacuum gauge measurement value reaches the experimental pressure P0. 5.The vacuum synchronicity measurement system of the SPERF device according to claim 4, characterized in that, the experimental pressure P0 is between 9.9e-7 Pa and 1e-2 Pa.

6. The vacuum synchronicity measurement system of the SPERF device of claim 4, wherein, The voltage range of the analog voltage signal of the vacuum gauge in the SPERF device is 0V-10V.

7. The vacuum synchronicity measurement system of a SPERF device of claim 4, 5 or 6, characterized in that, The reference optical fiber is connected to the collection unit through an optical-electric converter. 8.A control method for a SPERF device, characterized in that, the time jitter T is measured by using the method for measuring the vacuum synchronicity of the SPERF device according to any one of claims 1 to 3; The opening valve position of the piezoelectric ceramic valve is controlled by adjusting the threshold voltage of the driver in the SPERF device until Δt BA > T + t, where Δt BA is the time interval of the vacuum pressure measurement of the vacuum tank of the SPERF device from 80% P0 to P0 during the inflation process, t is the measurement reaction time of the vacuum gauge in the SPERF device, and P0 is the experimental pressure; the pulse width of the piezoelectric ceramic valve is adjusted by adjusting the pulse width of the trigger signal until the vacuum pressure measurement peak value reaches P0, The evacuation rate of the vacuum acquisition device is adjusted by the vacuum control system of the SPERF device until Δt AC > T + t, where Δt AC is the time interval in which the vacuum tank of the SPERF device goes from the pressure measurement P0 to 80% P0 after the end of the inflation.

9. The control method of the SPERF device according to claim 8, wherein, t=50ms. 10.The control method for the SPERF device according to claim 8 or 9, characterized in that, the experimental pressure P0 is between 9.9e-7 Pa and 1e-2 Pa.

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