Pressure reduction control method and system of rocket tank pressure safety system

Abstract

The invention provides a pressure reduction control method and system for a rocket tank pressure safety system. The rocket tank pressure safety system comprises a first pressure relief branch and a second pressure relief branch. The method comprises the steps of obtaining a first pressure value of the storage tank; determining an overpressure state of the storage tank according to the first pressure value; according to the overpressure state of the storage tank, switching to a first pressure relief branch for pressure relief; acquiring a second pressure value after the first pressure relief branch performs pressure relief for a first preset time period; according to a second pressure value and the first pressure value, a second three-way switching valve is controlled to be switched to a second pressure relief branch for pressure relief; acquiring a third pressure value of the second pressure relief branch after pressure relief for a second preset time period; and according to the third pressure value, the first pressure value and a blasting triggering threshold value of the blasting piece, the second three-way switching valve is controlled to be switched to the blasting piece, and the blasting piece is fractured to release pressure. Through flexible regulation and control of the redundant safety valve, the pressure control stability and universality are improved.

Description

Technical Field

[0001] This invention relates to the field of rocket propellant tank pressure control technology, and in particular to a pressure reduction control method and system for a rocket propellant tank pressure safety system. Background Technology

[0002] Currently, in the field of rocket pressurization and delivery, the main protection measures for system overpressure are a single safety valve or a rupture disc. The single safety valve solution involves directly connecting a single safety valve between the tank's vent and the relief pipe. When the tank pressure reaches the safety valve's set opening pressure, the valve automatically opens to release pressure and closes again once the pressure returns to normal. The rupture disc solution uses a thin metal disc with a specific rated burst pressure, connected in series or parallel in the pressure relief channel. When the system pressure exceeds the rupture disc's rated pressure, the disc ruptures to achieve emergency pressure relief.

[0003] The core principle of these solutions is to achieve pressure relief protection during overpressure through passive response of mechanical structures or simple parallel settings. The structures are relatively simple, mainly relying on the mechanical properties of the valves or rupture discs to complete the protective function. However, this single safety valve solution carries the risk of a single point of failure. Once the valve jams, fails to open or close, or leaks, the system will completely lose its overpressure protection capability, directly causing safety accidents such as tank overpressure and propellant leakage. Furthermore, safety valve failure is difficult to quickly locate and isolate, hindering effective fault diagnosis and risk identification, and making fault reproduction and problem investigation difficult. The valve body, pipelines, and fluids are prone to fluid-structure interaction vibrations, and factors such as flight vibrations can further affect pressure control accuracy. The adjustable range is narrow, valve coordination is inflexible, and fault isolation is insufficient, posing safety hazards. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a pressure reduction control method and system for a rocket propellant tank pressure safety system, eliminate the hidden danger of single-point failure, ensure that the system can still maintain the pressure relief function when a single valve fails, and improve the safety under extreme conditions and the success rate of launch missions.

[0005] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: A pressure reduction control method for a rocket propellant tank pressure safety system, wherein the rocket propellant tank pressure safety system includes: a propellant tank; a pressure sensor connected to a first vent port of the propellant tank; a first three-way switching valve connected to a second vent port of the propellant tank, wherein the first vent port and the second vent port are at the same vertical height relative to the horizontal line; a second three-way switching valve connected to the first three-way switching valve; a rupture disc connected to the first three-way switching valve; a first pressure relief branch connected to the first three-way switching valve; and a second pressure relief branch connected to the first three-way switching valve. The method includes: acquiring a first pressure value at the first vent of the storage tank using the pressure sensor; The overpressure state of the tank is determined based on the first pressure value; Based on the overpressure state of the storage tank, the pressure is released by switching to the first pressure relief branch through the first three-way switching valve; The pressure sensor is used to obtain the second pressure value after the first pressure relief branch has been depressurized for a first preset time period. Based on the second pressure value and the first pressure value, control the first three-way switching valve to switch to the second three-way switching valve, and control the second three-way switching valve to switch to the second pressure relief branch for pressure relief; The pressure sensor is used to obtain the third pressure value after the second pressure relief branch has been depressurized for a second preset time period. Based on the third pressure value, the first pressure value, and the bursting trigger threshold of the rupture disc, the second three-way switching valve is controlled to switch to the rupture disc, and the rupture disc automatically breaks to release pressure.

[0006] Optionally, determining the overpressure state of the tank based on the first pressure value includes: Based on the first pressure value, the preset overpressure trigger threshold, and the pressure hysteresis, it is determined that the tank is in a state without overpressure. When the tank is determined to be in an overpressure state based on multiple continuously collected first pressure values ​​and a preset overpressure trigger threshold, the tank is further determined to be in a first overpressure state based on the currently collected first pressure value, the preset overpressure trigger threshold, and the first overpressure trigger threshold; the first overpressure trigger threshold is greater than the preset overpressure threshold. The tank is then determined to be in a second overpressure state based on the first pressure value, the first overpressure trigger threshold, and the second overpressure trigger threshold; the second overpressure trigger threshold is greater than the first overpressure trigger threshold. Finally, the tank is determined to be in a third overpressure state based on the first pressure value and the second overpressure trigger threshold; the second overpressure trigger threshold is greater than the first overpressure trigger threshold.

[0007] Optionally, based on multiple continuously collected first pressure values ​​and a preset overpressure trigger threshold, the tank is determined to be in an overpressure state, including: according to The tank was determined to be under overpressure. Where k is the number of consecutively collected first pressure values. Indicates an indicator function, This indicates the preset overpressure trigger threshold. This represents the i-th first pressure value, and N is the number of first pressure values ​​that are greater than the preset overpressure trigger threshold.

[0008] Optionally, pressure relief is achieved by switching to the first pressure relief branch via the first three-way switching valve, including: If the overpressure state is the first overpressure state, the first three-way switching valve is used to switch to the first pressure relief branch for pressure relief, and the first electromagnetic isolation valve and the first safety valve of the first pressure relief branch are opened to release pressure at the first preset flow rate. If the overpressure state is the second overpressure state, the pressure is released by switching to the first pressure relief branch through the first three-way switching valve, and the first electromagnetic isolation valve and the first safety valve of the first pressure relief branch are opened to release pressure at the second preset flow rate.

[0009] Optionally, the first preset flow rate pressure relief is based on Sure; in, , ;in, This indicates the first preset flow rate for pressure relief. The minimum required pressure relief mass flow rate, To control the required pressure relief flow, For maximum heat load, The specific heat at constant pressure of the gas in the storage tank. This is an approximate temperature drop during the pressure relief process. The gas phase volume of the storage tank. The molecular weight of the gas is... This is the universal gas constant. The compressibility factor of a gas. The design temperature of the gas inside the storage tank. For pressure grading intervals, To the maximum allowable settling time, For safety factor; The second preset flow rate pressure relief is based on: Sure; in, This is the flow amplification factor. This indicates the second preset flow rate for pressure relief.

[0010] Optionally, the pressure reduction control method of the rocket propellant tank pressure safety system also includes: according to and Determine whether the first solenoid isolation valve in the first pressure relief branch or the second solenoid isolation valve in the second pressure relief branch is faulty; in, For the current moment, The moment when a closing or opening command is issued to the electromagnetic isolation valve. =2s, The position signal of the electromagnetic isolation valve is fed back by the position sensor built into the valve. The position signal indicates the degree of opening and closing of the electromagnetic isolation valve.

[0011] Optionally, the pressure reduction control method of the rocket propellant tank pressure safety system also includes: If the first solenoid isolation valve fails to isolate, the second three-way switching valve is controlled to open the second solenoid isolation valve and the second safety valve on the second pressure relief branch to relieve pressure, while the first solenoid isolation valve and the first safety valve on the first pressure relief branch are closed, and the valve opening of the second safety valve is adjusted. If both the first and second electromagnetic isolation valves fail to isolate, the rupture disc will be triggered to release pressure.

[0012] Optionally, the pressure reduction control method of the rocket propellant tank pressure safety system also includes: according to Early warning valve failure probability; among which, This represents the probability of valve failure. The number of times the valve operates. This represents the limit number of valve actuations. The average response time of the valve action. The standard response time for valve action. The maximum permissible response time for valve actuation; the valve includes any one of the following: a first solenoid isolation valve (3a) and a first safety valve (4a), a second solenoid isolation valve (3b), and a second safety valve (4b).

[0013] Embodiments of the present invention also provide a rocket propellant tank pressure safety control system, comprising: Storage tank; pressure sensor connected to the storage tank; The first pressure relief branch connected to the storage tank; The second pressure relief branch is connected to the storage tank; The rupture disc connected to the storage tank; The first pressure relief branch is provided with a first three-way switching valve, a first electromagnetic isolation valve and a first safety valve in sequence; the second pressure relief branch is provided with a second three-way switching valve, a second electromagnetic isolation valve and a second safety valve in sequence. A controller connected to the pressure sensor, the first pressure relief branch, and the second pressure relief branch acquires a first pressure value at the first vent of the storage tank via the pressure sensor; determines the overpressure state of the storage tank based on the first pressure value; switches to the first pressure relief branch via the first three-way switching valve to relieve pressure based on the overpressure state of the storage tank; acquires a second pressure value after a first preset time period of pressure relief via the first pressure relief branch via the pressure sensor; controls the first three-way switching valve to switch to the second three-way switching valve and controls the second three-way switching valve to switch to the second pressure relief branch to relieve pressure based on the second pressure value and the first pressure value; acquires a third pressure value after a second preset time period of pressure relief via the second pressure relief branch via the pressure sensor; and controls the second three-way switching valve to switch to the rupture disc based on the third pressure value, the first pressure value, and the bursting trigger threshold of the rupture disc, allowing the rupture disc to automatically rupture and relieve pressure.

[0014] Optionally, either the first three-way switching valve or the second three-way switching valve includes: Movable valve core; A first and second plug, nested on a movable valve core, are axially opposed. A sealing ring positioned at the midpoint between the movable valve core and the valve body, along the direction of the first plug and the second plug; The gas inlet in the storage tank is located on one side of the movable valve core; The first and second outlets are located on the other side of the movable valve core; An inlet for control air is located in the direction of movement of the movable valve core; When the control gas is not activated, the movable valve core is in its initial position, the second plug closes the gas path of the second outlet, and the inlet is connected to the first outlet, so the gas in the tank flows from the inlet to the first outlet; when the control gas is introduced, the control gas pushes the valve core to move, the first plug closes the gas path of the first outlet, the inlet is connected to the second outlet, and the gas in the tank flows from the inlet to the second outlet, thus realizing branch switching and pressure relief.

[0015] The above-described solution of the present invention has at least the following beneficial effects: The above-mentioned solution of the present invention monitors the pressure of the rocket propellant tank by using a pressure sensor installed on the tank to determine the overpressure state. Then, based on the overpressure state, it controls two parallel pressure relief branches and a triple redundant pressure relief path of the rupture disc to relieve pressure. This eliminates the risk of single-point failure, ensures that the system can still maintain the pressure relief function when a single valve fails, improves the safety under extreme conditions and the success rate of launch missions, thereby achieving pressure safety control and improving the stability and versatility of pressure control for the propellant tank. Attached Figure Description

[0016] Figure 1This is a schematic flowchart of an embodiment of the pressure reduction control method of the rocket propellant tank pressure safety system of the present invention; Figure 2 This is a schematic diagram of the rocket tank pressure safety control system of the present invention; Figure 3 This is a schematic diagram of an application scenario of the rocket tank pressure safety control system of the present invention; Figure 4 This is a schematic diagram of the first three-way switching valve and the second three-way switching valve.

[0017] Explanation of reference numerals in the attached figures: 1: Rupture disc; 10: Storage tank; 2a: First three-way switching valve; 2b: Second three-way switching valve; 3a: First electromagnetic isolation valve; 3b: Second electromagnetic isolation valve; 4a: First safety valve; 4b: Second safety valve; 5a: First venting pipe; 5b: Second venting pipe; 6: Sealing ring; 7a: First plug; 7b: Second plug; 8: Inlet; 9a: First outlet; 9b: Second outlet; 11: Control gas inlet. Detailed Implementation

[0018] Exemplary embodiments of the invention will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0019] like Figure 1 As shown, an embodiment of the present invention proposes a decompression control method for a rocket propellant tank pressure safety system. The rocket propellant tank pressure safety system includes: a propellant tank 10; a pressure sensor connected to a first vent port of the propellant tank 10; a first three-way switching valve 2a connected to a second vent port of the propellant tank 10, wherein the first vent port and the second vent port are at the same vertical height relative to the horizontal line; a second three-way switching valve 2b connected to the first three-way switching valve 2a; a rupture disc 1 connected to the second three-way switching valve 2b; a first pressure relief branch connected to the first three-way switching valve 2a; and a second pressure relief branch connected to the second three-way switching valve 2b. The method includes: Step 11: Obtain the first pressure value of the first vent of the storage tank 10 through the pressure sensor; Step 12: Determine the overpressure state of the storage tank 10 based on the first pressure value; Step 13: Based on the overpressure state of the storage tank 10, switch to the first pressure relief branch through the first three-way switching valve 2a to relieve pressure; Step 14: Obtain the second pressure value after the first pressure relief branch has been depressurized for a first preset time period through the pressure sensor; Step 15: Based on the second pressure value and the first pressure value, control the first three-way switching valve 2a to switch to the second three-way switching valve 2b, and control the second three-way switching valve 2b to switch to the second pressure relief branch for pressure relief; Step 16: Obtain the third pressure value after the second pressure relief branch has been depressurized for a second preset time period using the pressure sensor; Step 17: Based on the third pressure value, the first pressure value, and the bursting trigger threshold of the rupture disc 1, control the second three-way switching valve 2b to switch to the rupture disc 1, so that the rupture disc 1 automatically breaks to release pressure.

[0020] In this embodiment of the invention, the pressure of the storage tank 10 is monitored by a pressure sensor to determine the overpressure state, and the two parallel pressure relief branches and the triple redundant pressure relief path of the rupture disc are controlled to relieve pressure according to the overpressure state; this eliminates the risk of single-point failure, ensures that the system can still maintain the pressure relief function when a single valve fails, improves the safety under extreme conditions and the success rate of launch missions, thereby achieving pressure safety control, and also improves the stability and versatility of pressure control, reduces the impact of factors such as vibration on control accuracy, and broadens the range of working conditions adaptable.

[0021] In the above embodiments of the present invention, the first pressure relief branch includes: a first electromagnetic isolation valve 3a connected to the first three-way switching valve 2a, and a first safety valve 4a connected to the first electromagnetic isolation valve 3a, wherein the first safety valve 4a is connected to the first discharge pipe 5a. The second pressure relief branch includes: a second electromagnetic isolation valve 3b connected to the second three-way switching valve 2b, and a second safety valve 4b connected to the second electromagnetic isolation valve 3b, wherein the second safety valve 4b is connected to the second relief pipe 5b; In this embodiment, when controlling the first pressure relief branch to relieve pressure, the first electromagnetic isolation valve 3a and the first safety valve 4a are opened to achieve pressure relief.

[0022] When controlling the pressure relief of the second pressure relief branch, the second electromagnetic isolation valve 3b and the second safety valve 4b are opened, while the first electromagnetic isolation valve 3a and the first safety valve 4a are closed, thereby realizing pressure relief through the second pressure relief branch.

[0023] In some alternative implementations, step 12, determining the overpressure state of the tank 10 based on the first pressure value, includes: Step 121: Based on the first pressure value, the preset overpressure trigger threshold, and the pressure hysteresis, determine that the storage tank 10 is in a state without overpressure. Step 122: When it is determined that the storage tank 10 is in an overpressure state based on multiple continuously collected first pressure values ​​and a preset overpressure trigger threshold, the storage tank 10 is determined to be in a first overpressure state based on the currently collected first pressure value, the preset overpressure trigger threshold, and the first overpressure trigger threshold; the first overpressure trigger threshold is greater than the preset overpressure threshold. Based on the first pressure value, the first overpressure trigger threshold, and the second overpressure trigger threshold, the storage tank 10 is determined to be in a second overpressure state; the second overpressure trigger threshold is greater than the first overpressure trigger threshold. Based on the first pressure value and the second overpressure trigger threshold, the storage tank 10 is determined to be in a third overpressure state; the second overpressure trigger threshold is greater than the first overpressure trigger threshold.

[0024] In step 121: when At that time, the overpressure state is defined as no overpressure, where, To preset the overpressure trigger threshold, For pressure hysteresis, This is the first pressure value; In step 122, determining that the storage tank 10 is in an overpressure state based on multiple continuously collected first pressure values ​​and a preset overpressure trigger threshold may include: Step 1221: Obtain multiple first pressure values ​​continuously collected from the target historical time period starting from the current moment. The pressure sensor collects the original pressure signal Praw(t) at a sampling frequency of 100H, Ts=0.01s, and the collected data includes the pressure value and the corresponding time t. Step 1222: Remove outliers from the multiple continuously collected first pressure values. Assume that m=5 data points are collected consecutively as a group, and calculate the mean value within the group. and standard deviation : ; ; in, This indicates the number of first pressure values ​​in the target's historical time period. This indicates the first pressure value.

[0025] The i-th first pressure value satisfy - Take the pressure value. Let be the Grubbs critical value, when a = 0.05 and m = 5. =1.672.

[0026] If the extracted pressure value is continuous Each satisfies This confirms that the system is in an overpressure state. Where k is the number of consecutively collected first pressure values. Indicates an indicator function, This indicates the preset overpressure trigger threshold. This represents the i-th first pressure value, and N is the number of first pressure values ​​greater than the preset overpressure trigger threshold. If... If the number exceeds the preset number, the current overpressure state of storage tank 10 can be determined as an overpressure state.

[0027] In some embodiments, it can also be achieved through Determine the first overpressure state and the second overpressure state, for example, if If the number of overpressure states is greater than the preset number, it can be determined that the current overpressure state of tank 10 is the first overpressure state, i.e., a slight overpressure. The number of second overpressure states is greater than the preset number, which can be used to determine that the current overpressure state of tank 10 is the second overpressure state, that is, severe overpressure.

[0028] In step 122, determining that the storage tank 10 is in a first overpressure state based on the currently collected first pressure value, the preset overpressure trigger threshold, and the first overpressure trigger threshold may include: when At that time, the overpressure state is the first overpressure state, where, This is the first overpressure trigger threshold; In step 122, determining that the storage tank 10 is in a second overpressure state based on the first pressure value, the first overpressure trigger threshold, and the second overpressure trigger threshold may include: when At that time, the overpressure state is the second overpressure state, in which, This is the second overpressure trigger threshold; where, This is the first overpressure trigger threshold; In step 122, determining that the storage tank 10 is in a third overpressure state based on the first pressure value and the second overpressure trigger threshold may include: when At that time, the overpressure state is the third overpressure state; This is the second overpressure trigger threshold.

[0029] In the above embodiments of the present invention, , The safety performance indicators are determined based on the simulation results of the pressure safety system of the rocket propellant tank 10; the safety performance indicators are then used to determine the following: Second overpressure trigger threshold The hardware performance indicators of the rupture disc 1 are determined.

[0030] Among them, the safety performance indicators include: the peak pressure of tank 10 Worst-case rate of pressure rise System average response delay .

[0031] according to Determine each failure mode The highest pressure of tank 10 obtained from the simulation is as follows: Indicate each fault mode The tank pressure at each time t is 10. This indicates the peak pressure of tank 10; according to Determine the instantaneous rate of pressure change, where, This represents the worst-case rate of pressure increase. Indicates all failure modes The rate of pressure rise at each time t; The average system response delay is determined by statistically analyzing the average time it takes for all control valves to reach the specified opening degree after receiving a command. .

[0032] according to Determine the preset overpressure trigger threshold; in, This indicates the maximum pressure that the storage tank 10 and piping materials can withstand, and is usually determined by a design safety factor (such as 1.5 times the maximum working pressure). Represented as The preset safety margin (must be greater than the peak pressure of tank 10 in the simulation) and (maximum difference) Indicates the maximum permissible work pressure. , Indicates based on and Calculated operational margin This indicates the maximum allowable pressure change per unit time to ensure flight stability.

[0033] according to Determine the first overpressure trigger threshold; in, , in, This indicates the rated operating time of a redundant branch (such as a second pressure relief branch) from startup to fully establishing its pressure relief capacity. This is represented as a graded pressure interval, the value of which is calculated using the following formula to ensure that the redundant system has sufficient time to respond. The average system response delay is determined by the average time it takes for all control valves to reach the specified opening degree after receiving a command. This indicates the preset overpressure trigger threshold. This is the first overpressure trigger threshold.

[0034] according to Determine the upper limit of the rated pressure of rupture disc 1, whereby, This indicates the maximum pressure that the tank 10 and piping materials can withstand. This is a physical upper limit verified through material strength, structural simulation, and destructive testing. The safety margin (Pa) is set to protect the structure of the storage tank 10. This margin is used to cover unknown factors such as calculation errors and material property dispersion, and to ensure that the rupture disc 1 will inevitably activate before any permanent deformation or damage occurs to the storage tank 10.

[0035] according to Determine the lower limit of the rated pressure of rupture disc 1; in, This indicates the threshold for moderate overpressure. Indicates the pressure interval margin (Pa). , This indicates the estimated maximum rate of pressure increase (Pa / s). This represents the response time (in seconds) from when the system is fully open until the pressure begins to decrease.

[0036] Second overpressure trigger threshold Must meet: , and .

[0037] in, This indicates the tolerance factor (usually ±3%, ±5%, or ±10%). This is the system's maximum normal operating pressure (Pa). This is the maximum allowable duty cycle for Rupture Disc 1 (e.g., 0.7). This ensures that Rupture Disc 1 will not experience performance degradation due to prolonged exposure to high stress throughout the system's entire lifespan.

[0038] In some embodiments, pressure hysteresis , Due to current work pressure.

[0039] In some optional implementations, in step 13, based on the overpressure state of the storage tank 10, the pressure is released by switching to the first pressure relief branch via the first three-way switching valve 2a, including: If the overpressure state is the first overpressure state, the first three-way switching valve 2a is used to switch to the first pressure relief branch for pressure relief, and the first electromagnetic isolation valve 3a and the first safety valve 4a of the first pressure relief branch are opened to release pressure at the first preset flow rate. If the overpressure state is the second overpressure state, the first three-way switching valve 2a is used to switch to the first pressure relief branch for pressure relief, and the first electromagnetic isolation valve 3a and the first safety valve 4a of the first pressure relief branch are opened to release pressure at the second preset flow rate.

[0040] The formula for determining the first preset flow rate is as follows: ; in, , , in, This is the minimum pressure relief mass flow rate required based on energy balance calculation theory. To calculate the required pressure relief flow rate for control based on the pressure recovery rate, The maximum heat load (W) is the primary heat source causing the pressure rise in tank 10. The isobaric specific heat (J / (kg·K)) of the gas (such as nitrogen, helium, or vaporized propellant vapor) inside tank 10. This is the approximate temperature drop (K) during the pressure relief process. Let the gas phase volume of the storage tank be 10 m³, and take the minimum value under the most dangerous operating condition. The molecular weight of the gas (kg / mol) This is the universal gas constant. The compressibility factor for gases is used to correct for real gas effects. The design temperature (K) of the gas inside storage tank 10. The pressure grading interval, i.e. The flow rate design must ensure effective control within this pressure range. The maximum permissible settling time (s) is the time from the start of depressurization until the pressure stabilizes at the safe threshold (e.g., ...). The longest time allowed within ) This is a safety factor (>1, such as 1.2~1.5). It is used to cover calculation errors, model uncertainties, and component performance degradation.

[0041] The formula for determining the second preset flow rate is as follows: , The flow amplification factor (typically 1.5~2.5) is preferred. =2. When choosing a value for k, it is necessary to ensure... It has the ability to handle a faster pressure rise before the rupture fragmentation action.

[0042] In some alternative implementations, in step 14, the pressure sensor is used to obtain a second pressure value after the first pressure relief branch has been depressurized for a first preset time period.

[0043] In this embodiment, after the first pressure relief branch performs pressure relief for a first preset time period, the pressure in the storage tank 10 is continuously monitored to obtain a second pressure value, so as to know whether the first pressure relief branch has successfully relieved pressure. As an example, the first preset time period is a period of time after the first pressure relief branch is opened to relieve pressure, such as 3 seconds. The pressure change is continuously monitored by the pressure sensor. If the pressure drops to the normal range within t1=3 seconds after the first safety valve 4a is opened, the first safety valve 4a is kept open until the pressure stabilizes. Then, the first safety valve 4a and the first electromagnetic isolation valve 3a are gradually closed, and the system returns to normal. If the pressure does not drop within t1 time (the first safety valve 4a is determined to have failed), the control unit immediately sends a command: close the first electromagnetic isolation valve 3a, cut off the passage of the first safety valve 4a, and at the same time open the second electromagnetic isolation valve 3b and the second safety valve 4b, with the second safety valve 4b performing pressure relief.

[0044] In some alternative implementations, in step 15, based on the second pressure value and the first pressure value, the first three-way valve is controlled to switch to the second three-way switching valve 2b, and the second three-way switching valve 2b is controlled to switch to the second pressure relief branch for pressure relief.

[0045] In this embodiment, if the pressure drop rate of the second pressure value and the first pressure value is less than a preset value, it indicates that the pressure relief effect of the first pressure relief branch is not good and a malfunction may occur. Therefore, the first three-way valve is controlled to switch to the second three-way switching valve 2b, and the second three-way switching valve 2b is controlled to switch to the second pressure relief branch for pressure relief. Specifically, the second electromagnetic isolation valve 3b and the second safety valve 4b on the second pressure relief branch are controlled to open to relieve pressure at a preset flow rate. This embodiment further ensures the pressure relief effect.

[0046] For example, if the pressure drops to the normal range within t2=3 seconds after the second safety valve 4b is opened, keep the second safety valve 4b open until the pressure stabilizes, and then close the second safety valve 4b and the second solenoid isolation valve 3b. The system records the fault information of the first safety valve 4a and sends an alarm.

[0047] As an example, after the first pressure relief branch is activated, if the first preset time period... Internal pressure decline rate If the pressure relief fails, then the pressure relief is deemed unsuccessful. ,in, This indicates a change in valve status. The moment when the valve state is changed. This is the preset cycle.

[0048] In some alternative implementations, in step 16, the pressure sensor is used to obtain a third pressure value after the second pressure relief branch has been depressurized for a second preset time period.

[0049] In this embodiment, after the second pressure relief branch has released pressure for a second preset time period, the third pressure value of the storage tank 10 continues to be monitored to detect the pressure relief effect of the second pressure relief branch. As an example, the second preset time period is a period of time after the second pressure relief branch is opened for pressure relief.

[0050] In some alternative implementations, in step 17, the second three-way switching valve 2b is controlled to switch to the rupture disc based on the third pressure value, the first pressure value, and the rupture trigger threshold of the rupture disc, so that the rupture disc automatically ruptures to release pressure.

[0051] In this embodiment, the pressure drop rate of the third pressure value and the first pressure value is determined. If the pressure drop rate of the third pressure value and the first pressure value is less than the preset value, it indicates that the pressure relief effect of the second pressure relief branch is also poor and a malfunction may have occurred. In this case, the final pressure relief method is activated: the second three-way switching valve 2b is switched to the rupture disc, and the rupture disc automatically ruptures to relieve pressure. If the pressure still does not drop within t2 time (the dual valves are determined to have failed), the pressure continues to rise to the rated pressure of the rupture disc (1.5 times the working pressure), the rupture disc automatically ruptures, and emergency pressure is relieved through the relief pipeline. The control unit sends an extreme fault alarm and a shutdown signal. This embodiment further ensures the pressure relief effect.

[0052] In the above embodiments, after activating the first pressure relief branch, the system calculates the pressure drop rate within the target time period to assess the effectiveness of the pressure relief. If only the first pressure relief branch is activated but the pressure drop rate does not meet the preset requirement, the system will delay activating the second pressure relief branch as a supplement; if the second pressure relief branch is activated but the pressure drop rate still does not meet the standard, it indicates that both stages of active pressure relief may have failed, and the system will directly trigger the rupture disc 1 for final pressure relief. This forms a closed-loop safety control logic from monitoring and evaluation to dynamic switching of redundancy backup and finally to the activation of ultimate protection.

[0053] In some alternative implementations, regarding the pressure reduction control method of the rocket propellant tank 10 pressure safety system, if the pressure does not drop to the normal range within time t1 or t2 when pressure is released via the first or second pressure relief branch, the following methods can be used to determine whether the electromagnetic isolation valve has malfunctioned: Step 18, according to and Determine whether the first electromagnetic isolation valve 3a and the second electromagnetic isolation valve 3b on the first or second pressure relief branch are faulty. in, For the current moment, The moment when a closing or opening command is issued to the electromagnetic isolation valve. =2s, The position signal of the electromagnetic isolation valve is fed back by the position sensor built into the valve. The position signal indicates the degree of opening and closing of the electromagnetic isolation valve.

[0054] In this embodiment, the opening and closing states of the first electromagnetic isolation valve 3a and the second electromagnetic isolation valve 3b are generated by the control unit based on the state of the main safety valve. The valve drive module is controlled by a PWM signal, and the duty cycle D determines the valve action speed. Opening command: Duty cycle Dom=80%, drive voltage U=28V, to ensure rapid valve opening; Shutdown command: duty cycle Doff=20%, drive voltage U=28V, to avoid shock caused by shutting down too quickly.

[0055] The action is verified by the feedback signal F (F=1 indicates the valve is in position, F=0 indicates it is not in position) from the valve's built-in position sensor. If the command is sent... If no feedback is received within 2 seconds, the action is considered faulty. according to and Determine whether the first electromagnetic isolation valve 3a and the second electromagnetic isolation valve 3b on the first and second pressure relief branches are faulty.

[0056] In some alternative implementations, the pressure reduction control method of the rocket propellant tank 10 pressure safety system may also include: Step 20: If the first electromagnetic isolation valve 3a malfunctions, control the second three-way switching valve 2b to open the second electromagnetic isolation valve 3b and the second safety valve 4b on the second pressure relief branch to relieve pressure, and close the first electromagnetic isolation valve 3a and the first safety valve 4a on the first pressure relief branch, and according to... Adjust the valve opening of the second safety valve 4b, wherein, This refers to the valve opening degree of the second safety valve 4b. This is the current pressure value of tank 10. This is the threshold for moderate overpressure.

[0057] Step 21: If both the first electromagnetic isolation valve 3a and the second electromagnetic isolation valve 3b fail to isolate, the rupture disc 1 is triggered to release pressure.

[0058] In this embodiment, the rupture disc 1 is a passive protective component, whose triggering depends solely on system pressure. It automatically ruptures when the following condition is met: current pressure Furthermore, both main safety valves are in a malfunctioning state. This malfunction is confirmed by the control unit through switching logic, meaning that both first safety valve 4a and first safety valve B are open and the pressure has not decreased.

[0059] After rupture disc 1 ruptures, a sudden pressure drop is detected by the downstream pressure sensor. The control unit determines that rupture disc 1 has been triggered and records the trigger time and pressure peak value. The rupture fragment 1 was determined to be fractured. This represents the pressure value of tank 10 at time k. This represents the pressure value of tank 10 at time k-1. Indicates the preset period.

[0060] In some alternative implementations, the pressure reduction control method of the rocket propellant tank 10 pressure safety system may also include: Step 22, according to The probability of valve failure under early warning, among which, This represents the probability of valve failure. The number of times the valve operates. This represents the limit number of valve actuations. The average response time of the valve action. The standard response time for valve action. This refers to the maximum permissible response time for valve actuation. The valves mentioned here include any one of the following: first solenoid isolation valve 3a, second solenoid isolation valve 3b, first safety valve 4a, and second safety valve 4b. In this embodiment, the probability of valve failure is predicted by the number of times each valve is opened and closed (applicable to each valve in the pressure safety system of rocket tank 10). Specifically, this embodiment assigns a unique code to each type of fault (e.g., failure of first safety valve 4a = 0x01, VA action failure = 0x02, etc.), and the control unit determines the fault type through the fault identification matrix: Fault_Code= ,in, This is a fault condition. This indicates that the fault exists. This indicates no faults, and n is the total number of fault types.

[0061] In this embodiment, based on the number of valve actions Compared with average response time Establish a failure probability model to provide early warning of potential failures: ; in, , , This is the maximum allowable response time. When... At that time, a fault warning signal is sent.

[0062] In this embodiment, a circular storage mechanism is adopted. The stored data includes pressure curves, valve action sequences, fault codes, etc., and the storage address Addr is allocated according to the timestamp. [ modMar_Num; in, For the base address of the memory, The storage period is set to Mar_Num=10000, which is the maximum number of records to store, ensuring data traceability. For the current moment, This is the start time.

[0063] In some optional implementations, the scheduled switching period T = 72h, and the system continuous running time is set. And when there is no overpressure, automatically perform the switching test: Initiate a periodic switch, where, For the current time, This is the system initialization time.

[0064] The switching procedure is as follows: close the first electromagnetic isolation valve 3a and the first safety valve 4a, and open the first electromagnetic isolation valve VB and the second safety valve 4b.

[0065] like Figure 3 As shown, the specific implementation process of the above-mentioned method of the present invention includes: 1. System initialization phase: After the controller starts, it first sends a calibration command to the pressure sensor to complete the zero point and range calibration; Synchronously read the valve opening and closing status of the first safety valve 4a and the second safety valve 4b, as well as the position feedback signals of the first electromagnetic isolation valve 3a and the second electromagnetic isolation valve 3b, to confirm that the initial state of all valves is normal. Verify the integrity of the rupture disc assembly 1 (confirm no leakage through built-in monitoring points); Real-time monitoring: After initialization, the controller sends a "ready" signal to the control system, and the system enters normal monitoring mode. The first electromagnetic isolation valve 3a and the second electromagnetic isolation valve are closed, and the first safety valve 4a and the second safety valve 4b are on standby.

[0066] 2. Logical judgment and valve action adjustment for different operating conditions of the non-system: (1) Normal working conditions: The pressure sensor continuously monitors the pressure of tank 10, and the control unit receives the pressure data sent by the pressure sensor in real time. If the pressure is maintained within the normal operating pressure range, all components remain in their initial state, and the system continues to monitor.

[0067] (2) Overpressure relief condition: When the real-time pressure exceeds the overpressure trigger threshold (e.g., 1.2 times the working pressure), the controller immediately sends a command: to open the first solenoid isolation valve 3a and simultaneously drive the first safety valve 4a to open and release pressure. The controller continuously monitors the pressure change of the storage tank 10. If the pressure drops to the normal range within t1=3 seconds after the first safety valve 4a is opened, the first safety valve 4a is kept open until the pressure stabilizes. Then, the first safety valve 4a and the first solenoid isolation valve 3a are gradually closed, and the system returns to normal. If the pressure does not drop within time t1 (the first safety valve 4a is determined to be faulty), the controller immediately sends a command: close the first safety valve 4a, cut off the passage of the first safety valve 4a, and at the same time open the second safety valve 4b and the second electromagnetic isolation valve 3b, and the second safety valve 4b performs pressure relief. If the pressure drops to the normal range within t2=3 seconds after the second safety valve 4b is opened, keep the second safety valve 4b open until the pressure stabilizes, and then close the second safety valve 4b and the second solenoid isolation valve 3b. The system records the fault information of the first safety valve 4a and sends an alarm to the designated system. If the pressure does not decrease within time t2 (indicating dual valve failure), and the pressure continues to rise to the rated pressure of the rupture disc (e.g., 1.5 times the working pressure), the rupture disc 1 will automatically rupture, releasing pressure urgently through the relief pipe, and the control unit will send an extreme fault alarm and shutdown signal.

[0068] 3. Regularly switch to testing: When the system runs continuously for a preset period (the preset period can be modified via ground commands) and there is no overpressure condition, the controller initiates a periodic switching test. If the current main valve is the first safety valve 4a, the control unit sends a command: close the first electromagnetic isolation valve 3a, open the second electromagnetic isolation valve 3b and the second safety valve 4b, keep the second safety valve 4b open for 5 seconds and then close it to verify the effectiveness of the second safety valve 4b's action. After the test is completed, switch back to the first safety valve 4a as the main valve, and the controller records the test data; If the second safety valve 4b is found to be malfunctioning during the test, the fault should be marked immediately and an alarm should be sent. Subsequent switching tests should only activate the first safety valve 4a until the fault is resolved.

[0069] 4. Troubleshooting status: When any component (pressure sensor, solenoid isolation valve, main safety valve) fails, the controller records the fault information (faulty component, time of occurrence, pressure data) immediately. In the event of a minor fault (such as fluctuations in sensor data), the system will continue to operate normally and send an alert. If it is a moderate fault (such as the failure of a single main safety valve), the system activates the backup channel to ensure that the pressure relief function is normal, and sends fault location information at the same time. In the event of a fatal malfunction (such as failure of the dual valves or rupture disc breakage), the system sends an emergency stop signal, and the onboard control system activates the emergency procedure to prevent the accident from escalating.

[0070] Meanwhile, the structural design of each valve can be optimized to adapt to low-temperature environments, solving problems such as brittleness of conventional materials, sealing failure, and valve freezing; while ensuring reliability, the overall structural complexity can be simplified, the weight of each device can be controlled, and the requirements for reusable rockets and low-cost operation can be met.

[0071] The above-mentioned method of the present invention achieves reliable pressure relief when the liquid oxygen methane rocket pressurization and delivery system is overpressurized through multiple physical and intelligent isolation control strategies, and automatically switches to the backup channel when the first safety valve 4a or the second safety valve 4b fails. It also has fault diagnosis and status feedback functions.

[0072] By designing a reasonable redundant architecture (i.e., the first pressure relief branch and the second pressure relief branch), the potential for single-point failure is eliminated, ensuring that the system can still maintain the pressure relief function when a single valve body fails, thereby improving safety under extreme conditions and the success rate of launch missions. By using electromagnetic isolation valves, main safety valves, and three-way switching valves, the system achieves coordinated control and rapid fault isolation of safety valves, avoiding secondary risks after excessive pressure relief or failure. It also provides accurate status feedback and fault diagnosis, supports telemetry and fault reproduction, improves the stability and versatility of pressure control, reduces the impact of factors such as vibration on control accuracy, and broadens the range of operating conditions it can adapt to.

[0073] like Figure 2 As shown, an embodiment of the present invention proposes a rocket propellant tank pressure safety control system, comprising: storage tank 1010; The pressure sensor is connected to the storage tank 10; The first pressure relief branch is connected to the storage tank 10; The second pressure relief branch is connected to the storage tank 10; The rupture disc 1 is connected to the storage tank 10; The first pressure relief branch is provided with a first three-way switching valve 2a, a first electromagnetic isolation valve 3a and a first safety valve 4a in sequence; the second pressure relief branch is provided with a second three-way switching valve 2b, a second electromagnetic isolation valve 3b and a second safety valve 4b in sequence. A controller connected to the pressure sensor, the first pressure relief branch, and the second pressure relief branch; the controller obtains a first pressure value at the first vent of the storage tank 10 through the pressure sensor; determines the overpressure state of the storage tank 10 based on the first pressure value; based on the overpressure state of the storage tank 10, switches to the first pressure relief branch through the first three-way switching valve 2a to relieve pressure; obtains a second pressure value after a first preset time period of pressure relief through the first pressure relief branch through the pressure sensor; controls the first three-way switching valve 2a to switch to the second three-way switching valve 2b based on the second pressure value and the first pressure value, and controls the second three-way switching valve 2b to switch to the second pressure relief branch to relieve pressure; obtains a third pressure value after a second preset time period of pressure relief through the second pressure relief branch through the pressure sensor; and controls the second three-way switching valve 2b to switch to the rupture disc 1 based on the third pressure value, the first pressure value, and the bursting trigger threshold of the rupture disc 1, so that the rupture disc 1 automatically breaks to relieve pressure.

[0074] In this embodiment, each of the two pressure relief branches of the system is sequentially equipped with a switching valve, an electromagnetic isolation valve (first electromagnetic isolation valve 3a and second electromagnetic isolation valve 3b), and a safety valve (first safety valve 4a and second safety valve 4b). The controller receives signals from the pressure sensor and automatically controls the opening and closing status of each valve on the two branches according to the real-time pressure value. A first relief pipe 5a is connected after the first safety valve 4a, and a first relief pipe 5b is connected after the second safety valve 4b for pressure relief. Combined with the rupture disc 1 as final protection, this constitutes a graded and redundant automatic pressure relief control system.

[0075] In this embodiment, the control logic of the controller can refer to the execution steps and embodiments of the pressure reduction control method of the rocket tank 10 pressure safety system.

[0076] This embodiment eliminates the risk of single-point failure through a reasonable redundant architecture design, ensuring that the system can still maintain the pressure relief function when a single valve fails, thereby improving safety under extreme conditions and the success rate of launch missions.

[0077] like Figure 4 As shown, in some optional implementations, both the first three-way switching valve 2a and the second three-way switching valve 2b include: Movable valve core; A first plug 7a and a second plug 7b, nested on a movable valve core, are axially opposite. A sealing ring 6 is located at the middle position between the movable valve core and the valve body, along the direction of the first plug 7a and the second plug 7b; The gas inlet 8 is located in the storage tank 10 on one side of the movable valve core; A first outlet 9a and a second outlet 9b are provided on the other side of the movable valve core; The control air inlet 10 is located in the direction of movement of the movable valve core; When the control gas is not activated, the movable valve core is in its initial position, the second plug 7b closes the gas path of the second outlet 9b, the inlet 8 is connected to the first outlet 9a, and the gas in the storage tank 10 flows from the inlet 8 to the first outlet 9a; when the control gas is introduced, the control gas pushes the valve core to move, the first plug 7a closes the gas path of the first outlet 9a, the inlet 8 is connected to the second outlet 9b, and the gas in the storage tank 10 flows from the inlet 8 to the second outlet 9b, realizing branch switching and pressure relief.

[0078] In this embodiment, both the first three-way switching valve 2a and the second three-way switching valve 2b are three-way switching valves, and their structures can be referred to as follows. Figure 4 The three-way switching valve includes a sealing ring 6, two axially opposed plugs (first plug 7a and second plug 7b), an inlet 8, two outlets (first outlet 9a and second outlet 9b), and a control air inlet 11. A movable component, the valve core, is located in the middle of the valve, and the valve core has a plug structure (first plug 7a and second plug 7b nested on the valve core). The sealing ring 6 is located in the middle of the valve core and valve body to achieve air circuit sealing and prevent gas leakage. The inlet 8 is located between the two plugs and serves as the air source input channel. The two outlets (first outlet 9a and second outlet 9b) serve as gas output channels. The control air inlet 11 is used to connect control air pressure to drive the valve core movement.

[0079] When the initial / control gas is not activated, the movable valve core is in the initial position, the second plug 7b closes the gas path of the second outlet 9b, and the inlet 8 and the first outlet 9a are connected, allowing gas in the storage tank 10 to flow from the inlet 8 to the first outlet 9a. When the control gas is introduced, it pushes the valve core to move, the first plug 7a closes the gas path of the first outlet 9a, and the inlet 8 and the second outlet 9b are connected, allowing gas in the storage tank 10 to flow from the inlet 8 to the second outlet 9b. By changing the valve core position through the on / off state of the control gas, and utilizing the cooperation of the plug and the sealing ring, the gas path switching between the inlet and outlet 1 and outlet 2 is achieved, ensuring that only one outlet is connected to the inlet at any given time, while the other outlet is closed, thereby realizing branch switching and pressure relief.

[0080] In one application scenario, refer to Figure 3 The full-condition operation flow of the pressure safety system of the aforementioned rocket propellant tank 10 is as follows: 1. System initialization phase: (1) After the control unit is started, it first sends a calibration command to the pressure sensor to complete the zero point and range calibration; (2) Synchronously read the valve opening and closing status of the first safety valve 4a and the second safety valve 4b, as well as the position feedback signals of the first electromagnetic isolation valve 3a and the second electromagnetic isolation valve 3b, to confirm that the initial state of all valves is normal. (3) Verify the integrity of the rupture disc assembly 1 (confirm no leakage through the monitoring point built into the valve); (4) The controller sends a "ready" signal to the control system, the system enters normal monitoring mode, the first electromagnetic isolation valve 3a and the second electromagnetic isolation valve are closed, and the first safety valve 4a and the second safety valve 4b are on standby.

[0081] The valve control is as follows, depending on the operating conditions: 2. Normal working conditions: The pressure sensor continuously monitors the pressure of tank 10, and the controller receives the pressure data sent by the pressure sensor in real time. If the pressure is maintained within the normal operating pressure range, all components remain in their initial state, and the system continues to monitor.

[0082] 3. Overpressure relief condition: (1) When the real-time pressure exceeds the overpressure trigger threshold (e.g., 1.2 times the working pressure), the controller immediately sends a command: to open the first electromagnetic isolation valve 3a and at the same time drive the first safety valve 4a to open and release pressure; (2) The controller continuously monitors the pressure change. If the pressure drops to the normal range within t1=3 seconds after the first safety valve 4a is opened, the first safety valve 4a is kept open until the pressure stabilizes. Then the first safety valve 4a and the first electromagnetic isolation valve 3a are gradually closed and the system returns to normal. (3) If the pressure does not drop within time t1 (the first safety valve 4a is determined to be faulty), the controller immediately sends an instruction: close the first safety valve 4a, cut off the passage of the first safety valve 4a, and at the same time open the second safety valve 4b and the second electromagnetic isolation valve 3b, and the second safety valve 4b performs pressure relief. (4) If the pressure drops to the normal range within t2=3 seconds after the second safety valve 4b is opened, keep the second safety valve 4b open until the pressure stabilizes, and then close the second safety valve 4b and the second electromagnetic isolation valve 3b. The system records the fault information of the first safety valve 4a and sends an alarm to the designated system. (5) If the pressure does not decrease within time t2 (indicating dual valve failure), and the pressure continues to rise to the rated pressure of rupture disc 1 (1.5 times the working pressure), rupture disc 1 will automatically rupture, releasing pressure urgently through the relief pipe. The control unit will send an extreme fault alarm and shutdown signal. At this time, the dual main safety valves are the priority pressure relief components, and the rupture disc 1 assembly is the ultimate pressure relief component. Only when both main safety valves fail and the pressure rises to the rated pressure of rupture disc 1 will rupture and release pressure automatically. The two form a hierarchical collaborative relationship of "priority execution - ultimate fallback," ensuring safety protection under extreme overpressure scenarios. The controller can send a switching command to the three-way switching valve according to a preset cycle (e.g., 72 hours) or fault status. After receiving the command, the three-way switching valve adjusts the passage to realize the switching of the main and backup safety valve channels. The two form a test and redundancy collaborative relationship of "command triggering - passage switching," ensuring the effectiveness of the backup safety valve function.

[0083] For different operating conditions, the controller sends opening and closing commands to the solenoid isolation valves and the main safety valve based on the pressure judgment result and valve status feedback. Under normal operating conditions, the control unit outputs a closing signal, and both solenoid isolation valves (first solenoid isolation valve 3a and second solenoid isolation valve 3b) are closed, while the main safety valves (first safety valve 4a and second safety valve 4b) are in standby mode. Under overpressure conditions, the controller first sends an opening signal to the first solenoid isolation valve 3a and the first safety valve 4a. If the first safety valve 4a is determined to be faulty, it immediately sends a closing signal to the first solenoid isolation valve 3a and simultaneously sends an opening signal to the second solenoid isolation valve 3b and the second safety valve 4b. The three form an execution coordination relationship of "command-driven - action execution - status feedback".

[0084] 4. Regularly switch test conditions: (1) When the system runs continuously for a period of time (the preset period can be modified by ground command) and there is no overpressure condition, the controller starts the periodic switching test; (2) If the current main valve is the first safety valve 4a, the control unit sends the command: close the first electromagnetic isolation valve 3a, open the second electromagnetic isolation valve 3b and the second safety valve 4b, keep the second safety valve 4b open for 5 seconds and then close it to verify the effectiveness of the action of the second safety valve 4b; (3) After the test is completed, switch back to the first safety valve 4a as the main valve, and the controller records the test data; (4) If the second safety valve 4b is found to be malfunctioning during the test, immediately mark the fault and send an alarm. Subsequent switching tests should only activate the first safety valve 4a until the fault is resolved. 5. Fault handling conditions: When any component (pressure sensor, solenoid isolation valve, main safety valve) fails, the controller records the fault information (faulty component, time of occurrence, pressure data) immediately. (2) If it is a minor fault (such as fluctuations in sensor data), the system will continue to operate normally and send an early warning; (3) If it is a moderate fault (such as the failure of a single main safety valve), the system starts the backup channel to ensure that the pressure relief function is normal, and sends fault location information at the same time; (4) If it is a fatal malfunction (such as failure of the double valve or rupture disc 1), the system sends an emergency stop signal and the on-board control system starts the emergency procedure to prevent the accident from escalating.

[0085] Each time a valve is activated (opening, closing, switching) or a fault occurs, the controller sends a status report (including pressure data, valve status, and fault information) to the onboard control system in real time. The control system can receive the information and issue emergency commands (such as triggering a shutdown in case of an extreme fault). The two form a communication and coordination relationship of "status reporting - command issuance".

[0086] In the above embodiments, the pressure sensors collect pressure data in the storage tank 10 at a fixed frequency (fixed frequency ≥ 100Hz), convert the analog signal into a digital signal and transmit it to the controller in real time. The controller compares the pressure data with a preset threshold to provide a decision basis for subsequent action commands. The two form a pre-coordinated relationship of "data acquisition - signal transmission - logical judgment".

[0087] The system of this invention provides a redundant safety valve group architecture. Through multiple physical and intelligent isolation control strategies, it achieves reliable pressure relief in the liquid oxygen-methane rocket pressurization and delivery system during overpressure. In the event of a single safety valve failure, it automatically switches to a backup channel and also possesses fault diagnosis and status feedback functions. It should be noted that the pressure reduction control method of the rocket tank 10 pressure safety system described above corresponds to the method of the rocket tank 10 pressure safety control system described above. All implementation methods in the above method embodiments are applicable to the embodiments of this system. Similarly, all implementation methods in the above system embodiments are applicable to the embodiments of the above method, and can achieve the same technical effects.

[0088] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A pressure reduction control method for a rocket propellant tank pressure safety system, characterized in that, The rocket propellant tank pressure safety system includes: a propellant tank (10); a pressure sensor connected to a first vent of the propellant tank (10); a first three-way switching valve (2a) connected to a second vent of the propellant tank (10), wherein the first vent and the second vent are at the same vertical height relative to the horizontal line; a second three-way switching valve (2b) connected to the first three-way switching valve (2a); a rupture disc (1) connected to the first three-way switching valve (2a); a first pressure relief branch connected to the first three-way switching valve (2a); and a second pressure relief branch connected to the first three-way switching valve (2a); the method includes: The first pressure value of the first vent of the storage tank (10) is obtained by the pressure sensor; The overpressure state of the storage tank (10) is determined based on the first pressure value; According to the overpressure state of the storage tank (10), the pressure is released by switching to the first pressure relief branch through the first three-way switching valve (2a); The pressure sensor is used to obtain the second pressure value after the first pressure relief branch has been depressurized for a first preset time period. Based on the second pressure value and the first pressure value, control the first three-way switching valve (2a) to switch to the second three-way switching valve (2b), and control the second three-way switching valve (2b) to switch to the second pressure relief branch for pressure relief; The pressure sensor is used to obtain the third pressure value after the second pressure relief branch has been depressurized for a second preset time period. Based on the third pressure value, the first pressure value, and the burst trigger threshold of the rupture disc (1), the second three-way switching valve (2b) is controlled to switch to the rupture disc (1), and the rupture disc (1) automatically breaks to release pressure.

2. The pressure reduction control method for the rocket propellant tank pressure safety system according to claim 1, characterized in that, Determining the overpressure state of the storage tank (10) based on the first pressure value includes: Based on the first pressure value, the preset overpressure trigger threshold and the pressure hysteresis, the storage tank (10) is determined to be in a state without overpressure; When the tank (10) is determined to be in an overpressure state based on multiple continuously collected first pressure values ​​and a preset overpressure trigger threshold, the tank (10) is determined to be in a first overpressure state based on the currently collected first pressure value, the preset overpressure trigger threshold, and the first overpressure trigger threshold; the first overpressure trigger threshold is greater than the preset overpressure threshold; the tank (10) is determined to be in a second overpressure state based on the first pressure value, the first overpressure trigger threshold, and the second overpressure trigger threshold; the second overpressure trigger threshold is greater than the first overpressure trigger threshold; the tank (10) is determined to be in a third overpressure state based on the first pressure value and the second overpressure trigger threshold; the second overpressure trigger threshold is greater than the first overpressure trigger threshold.

3. The pressure reduction control method for the rocket propellant tank pressure safety system according to claim 2, characterized in that, Based on the continuously collected first pressure values ​​and the preset overpressure trigger threshold, the storage tank (10) is determined to be in an overpressure state, including: according to The storage tank (10) was determined to be under overpressure. Where k is the number of consecutively collected first pressure values. Indicates an indicator function, This indicates the preset overpressure trigger threshold. This represents the i-th first pressure value, and N is the number of first pressure values ​​that are greater than the preset overpressure trigger threshold.

4. The pressure reduction control method for the rocket propellant tank pressure safety system according to claim 2 or 3, characterized in that, Pressure relief is achieved by switching to the first pressure relief branch via the first three-way switching valve (2a), including: If the overpressure state is the first overpressure state, the first three-way switching valve (2a) is used to switch to the first pressure relief branch for pressure relief, and the first electromagnetic isolation valve (3a) and the first safety valve (4a) of the first pressure relief branch are opened to release pressure at the first preset flow rate; If the overpressure state is the second overpressure state, the first three-way switching valve (2a) is used to switch to the first pressure relief branch for pressure relief, and the first electromagnetic isolation valve (3a) and the first safety valve (4a) of the first pressure relief branch are opened to release pressure at the second preset flow rate.

5. The pressure reduction control method for the rocket propellant tank pressure safety system according to claim 4, characterized in that, The first preset flow rate pressure relief is based on Sure; in, , ; in, This indicates the first preset flow rate for pressure relief. The minimum required pressure relief mass flow rate, To control the required pressure relief flow, For maximum heat load, The specific heat at constant pressure of the gas in the storage tank (10), This is an approximate temperature drop during the pressure relief process. For the gas phase volume of storage tank (10), The molecular weight of the gas is... This is the universal gas constant. The compressibility factor of a gas. The design temperature of the gas inside the storage tank (10) For pressure grading intervals, To the maximum allowable settling time, For safety factor; The second preset flow pressure relief is based on Sure; in, This is the flow amplification factor. This indicates the second preset flow rate for pressure relief.

6. The pressure reduction control method for the rocket propellant tank pressure safety system according to claim 1, characterized in that, Also includes: according to and Determine whether the first solenoid isolation valve (3a) of the first pressure relief branch or the second solenoid isolation valve (3b) of the second pressure relief branch is faulty; in, For the current moment, The moment when a closing or opening command is issued to the electromagnetic isolation valve. =2s, The position signal of the electromagnetic isolation valve is fed back by the position sensor built into the valve. The position signal indicates the degree of opening and closing of the electromagnetic isolation valve.

7. The pressure reduction control method for the rocket propellant tank pressure safety system according to claim 6, characterized in that, Also includes: If the first electromagnetic isolation valve (3a) fails to isolate, the second three-way switching valve (2b) is controlled to open the second electromagnetic isolation valve (3b) and the second safety valve (4b) on the second pressure relief branch to relieve pressure, and the first electromagnetic isolation valve (3a) and the first safety valve (4a) on the first pressure relief branch are closed, and the valve opening of the second safety valve (4b) is adjusted. If both the first electromagnetic isolation valve (3a) and the second electromagnetic isolation valve (3b) fail to isolate, the rupture disc (1) will be triggered to release pressure.

8. The pressure reduction control method for the rocket propellant tank pressure safety system according to claim 6, characterized in that, Also includes: according to Early warning valve failure probability; in, This represents the probability of valve failure. The number of times the valve operates. This represents the valve's maximum number of actuations. The average response time of the valve action. The standard response time for valve action. The maximum permissible response time for valve actuation; the valve includes any one of the following: a first solenoid isolation valve (3a) and a first safety valve (4a), a second solenoid isolation valve (3b), and a second safety valve (4b).

9. A rocket propellant tank pressure safety control system, characterized in that, include: Storage tank (10); pressure sensor connected to the storage tank (10); The first pressure relief branch connected to the storage tank (10); A second pressure relief branch connected to the storage tank (10); A rupture disc (1) connected to the storage tank (10); The first pressure relief branch is provided with a first three-way switching valve (2a), a first electromagnetic isolation valve (3a) and a first safety valve (4a) in sequence. The second pressure relief branch is equipped with a second three-way switching valve (2b), a second electromagnetic isolation valve (3b), and a second safety valve (4b) in sequence. The controller, connected to the pressure sensor, the first pressure relief branch, and the second pressure relief branch, obtains the first pressure value of the first exhaust port of the storage tank (10) through the pressure sensor; determines the overpressure state of the storage tank (10) based on the first pressure value; switches to the first pressure relief branch through the first three-way switching valve (2a) to relieve pressure based on the overpressure state of the storage tank (10); obtains the second pressure value after a first preset time period of pressure relief through the first pressure relief branch through the pressure sensor; controls the first three-way switching valve (2a) to switch to the second three-way switching valve (2b) based on the second pressure value and the first pressure value, and controls the second three-way switching valve (2b) to switch to the second pressure relief branch to relieve pressure based on the second pressure value and the first pressure value; obtains the third pressure value after a second preset time period of pressure relief through the second pressure relief branch through the pressure sensor; controls the second three-way switching valve (2b) to switch to the rupture disc (1) based on the third pressure value, the first pressure value, and the burst trigger threshold of the rupture disc (1), and the rupture disc (1) automatically ruptures to relieve pressure.

10. The rocket propellant tank pressure safety control system according to claim 9, characterized in that, Both the first three-way switching valve and the second three-way switching valve include: Movable valve core; A first plug (7a) and a second plug (7b) nested on a movable valve core, axially opposite each other; A sealing ring (6) is provided at the middle position between the movable valve core and the valve body, along the direction of the first plug (7a) and the second plug (7b); The gas inlet (8) is located in the storage tank (10) on one side of the movable valve core. A first outlet (9a) and a second outlet (9b) are provided on the other side of the movable valve core; The control gas inlet (10) is located in the direction of movement of the movable valve core. When the control gas is not activated, the movable valve core is in the initial position, the second plug (7b) closes the gas path of the second outlet (9b), the inlet (8) is connected to the first outlet (9a), and the gas in the tank (10) flows from the inlet (8) to the first outlet (9a). When the control gas is introduced, the control gas pushes the valve core to move, the first plug (7a) closes the gas path of the first outlet (9a), the inlet (8) is connected to the second outlet (9b), and the gas in the tank (10) flows from the inlet (8) to the second outlet (9b), realizing branch switching and pressure relief.

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