Low-temperature upper-stage power system

Abstract

The invention discloses a low-temperature upper-stage power system, and relates to the field of spaceflight. Comprising a gas cylinder, a pressure supplementing electromagnetic valve, a pressure supplementing pore plate, a self-generation pressurizing electromagnetic valve, a self-generation pressurizing pore plate, a storage tank, an overflow valve, a storage tank pressure sensor, a pressure stabilizing valve, a circulating pump, a circulating control valve, a pump front valve, a Joule-Thomson throttling expansion valve, a heat exchanger and a branch supply control valve; the main engine subsystem comprises a pump, a turbine, an auxiliary valve, a fuel gas generator, a main valve, a precooling backflow valve, a main thrust chamber, an evaporator, a starting gas cylinder, a starting gas cylinder control valve, a main thrust chamber igniter and a fuel gas generator igniter. The attitude control engine subsystem comprises a plurality of attitude control engines; each attitude control engine comprises an attitude control thrust chamber, and an oxidant control valve, a fuel control valve and an attitude control thrust chamber igniter are arranged on each attitude control thrust chamber. Propellant supply of the main engine and the attitude control engine is achieved through the unified pressurization conveying system.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of aerospace, in particular to a low-temperature upper stage power system. BACKGROUND

[0002] The low-temperature upper stage power system is a power system using low-temperature propellant in a rocket upper stage. The current low-temperature upper stage power system includes a main propulsion system and an attitude control power system. The main propulsion system usually uses liquid oxygen / kerosene and liquid oxygen / methane dual-component low-temperature propellants, matches a low-pressure tank and a pump pressure type engine. The attitude control power system usually uses nitrogen tetroxide / methyl hydrazine normal temperature propellant, matches a high-pressure tank and an extrusion type engine.

[0003] The current low-temperature upper stage power system has the following problems:

[0004] (1) The complexity caused by the independence of the two sets of power systems is too high: the main propulsion system and the attitude control power system are two independent systems, the pressurization and delivery system cannot be shared, resulting in a large number of propellants and components, complex use and maintenance, and restricting the improvement of launch efficiency.

[0005] (2) Defects of the attitude control power system: the attitude control power system uses a high-pressure tank, which is relatively heavy; at the same time, the engine uses normal temperature oxidant, which has the problem of low specific impulse of the engine.

[0006] (3) Heat management requirement problem: there is heat interaction between the low-temperature main propulsion system and the normal temperature attitude control power system, and heat management design and adaptation need to be carried out. SUMMARY

[0007] The purpose of the present application is to provide a low-temperature upper stage power system, which realizes the supply of propellants for the main engine and the attitude control engine through a unified pressurization and delivery system, improves the utilization rate of propellants by adopting the combination of an electric pump and a pressure stabilizing valve, improves the specific impulse of the main engine and the attitude control engine by using low-temperature propellants, simplifies the components of the upper stage power system, reduces the total weight of the power system, and optimizes the use and maintenance requirements.

[0008] To achieve the above object, the application provides a low-temperature upper stage power system, which comprises the following: the outlet of a gas cylinder of a pressurized delivery subsystem is communicated with one end of a first oxygen path pressure compensation electromagnetic valve, the other end of the first oxygen path pressure compensation electromagnetic valve is communicated with a first oxygen path pressure compensation orifice plate, and the first oxygen path pressure compensation orifice plate is communicated with a pressurized inlet of an oxidant storage tank; the outlet of the gas cylinder is communicated with one end of a second oxygen path pressure compensation electromagnetic valve, one end of the second oxygen path pressure compensation electromagnetic valve is communicated with one end of the first oxygen path pressure compensation electromagnetic valve, the other end of the second oxygen path pressure compensation electromagnetic valve is communicated with a second oxygen path pressure compensation orifice plate, and the second oxygen path pressure compensation orifice plate is communicated with the first oxygen path pressure compensation orifice plate and the pressurized inlet of the oxidant storage tank; the outlet of the gas cylinder is communicated with one end of a first fuel path pressure compensation electromagnetic valve, the other end of the first fuel path pressure compensation electromagnetic valve is communicated with a first fuel path pressure compensation orifice plate, and the first fuel path pressure compensation orifice plate is communicated with a pressurized inlet of a fuel storage tank; the outlet of the gas cylinder is communicated with one end of a second fuel path pressure compensation electromagnetic valve, one end of the second fuel path pressure compensation electromagnetic valve is communicated with one end of the first fuel path pressure compensation electromagnetic valve, the other end of the second fuel path pressure compensation electromagnetic valve is communicated with a second fuel path pressure compensation orifice plate, and the second fuel path pressure compensation orifice plate is communicated with the first fuel path pressure compensation orifice plate and the pressurized inlet of the fuel storage tank; at least three oxidant storage tank pressure sensors, an oxidant relief valve and an oxidant filling port are arranged on the oxidant storage tank; at least three fuel storage tank pressure sensors, a fuel relief valve and a fuel filling port are arranged on the fuel storage tank; a bottom backflow port of the oxidant storage tank is communicated with a first outlet of an oxidant precooling backflow valve, and an inlet of the oxidant precooling backflow valve is communicated with a first outlet of an oxidant main valve; a second outlet of the oxidant main valve is communicated with a main thrust chamber of a main engine subsystem; an inlet of the oxidant main valve is communicated with an oxidant pump, an oxidant auxiliary valve and an oxidant evaporator; the oxidant auxiliary valve is communicated with a gas generator, the oxidant evaporator and the oxidant pump; the oxidant pump is communicated with the oxidant evaporator, an oxidant pump front valve and an oxidant circulation control valve; the main thrust chamber is provided with a main thrust chamber igniter; the main thrust chamber is communicated with a second outlet of a fuel main valve, a first outlet of the fuel main valve is communicated with an inlet of a fuel precooling backflow valve, and a first outlet of the fuel precooling backflow valve is communicated with a bottom backflow port of the fuel storage tank; an inlet of the fuel main valve is communicated with a fuel pump, a fuel auxiliary valve and a fuel evaporator; the fuel auxiliary valve is communicated with the gas generator, the fuel evaporator and the fuel pump; the fuel pump is communicated with the fuel evaporator, a fuel pump front valve and a fuel circulation control valve; the gas generator is communicated with a turbine; the turbine is communicated with a starting gas cylinder control valve, the starting gas cylinder control valve is communicated with a starting gas cylinder; the gas generator is provided with a gas generator igniter; the oxidant evaporator is communicated with one end of a first oxygen path self-generating pressure compensation electromagnetic valve, the other end of the first oxygen path self-generating pressure compensation electromagnetic valve is communicated with a first oxygen path self-generating pressure compensation orifice plate, and the first oxygen path self-generating pressure compensation orifice plate is communicated with the pressurized inlet of the oxidant storage tank, the first oxygen path pressure compensation orifice plate and the second oxygen path pressure compensation orifice plate.The oxidant evaporator is connected to one end of the second oxygen path self-generating pressure solenoid valve. One end of the second oxygen path self-generating pressure solenoid valve is connected to one end of the first oxygen path self-generating pressure solenoid valve. The other end of the second oxygen path self-generating pressure solenoid valve is connected to the second oxygen path self-generating pressure orifice plate. The second oxygen path self-generating pressure orifice plate is connected to the pressure inlet of the oxidant storage tank, the first oxygen path self-generating pressure orifice plate, the first oxygen path pressure replenishment orifice plate, and the second oxygen path pressure replenishment orifice plate. The oxidant evaporator is connected to the third oxygen path self-generating pressure orifice plate. One end of the third oxygen path self-generating pressure orifice plate is connected to one end of the first oxygen path self-generating pressure solenoid valve and one end of the second oxygen path self-generating pressure solenoid valve. The other end of the third oxygen path self-generating pressure orifice plate is connected to the first oxygen path self-generating pressure orifice plate, the second oxygen path self-generating pressure orifice plate, and the pressure inlet of the oxidant storage tank. The pressure port, the first oxygen circuit pressure-replenishing orifice plate, and the second oxygen circuit pressure-replenishing orifice plate are connected; the fuel evaporator is connected to one end of the first fuel circuit self-generated pressure-boosting solenoid valve, and the other end of the first fuel circuit self-generated pressure-boosting solenoid valve is connected to the first fuel circuit self-generated pressure-boosting orifice plate. The first fuel circuit self-generated pressure-boosting orifice plate is connected to the pressure-boosting port of the fuel tank, the first fuel circuit pressure-replenishing orifice plate, and the second fuel circuit pressure-replenishing orifice plate. The fuel evaporator is connected to one end of the second fuel circuit self-generated pressure-boosting solenoid valve, and one end of the second fuel circuit self-generated pressure-boosting solenoid valve is connected to one end of the first fuel circuit self-generated pressure-boosting solenoid valve. The other end of the second fuel circuit self-generated pressure-boosting solenoid valve is connected to the second fuel circuit self-generated pressure-boosting orifice plate. The second fuel circuit self-generated pressure-boosting orifice plate is connected to the pressure-boosting port of the fuel tank, the first fuel circuit self-generated pressure-boosting orifice plate, the first fuel circuit pressure-replenishing orifice plate, and the second fuel circuit pressure-replenishing orifice plate. The system is connected to the fuel evaporator and the third fuel circuit self-generating pressure orifice plate. One end of the third fuel circuit self-generating pressure orifice plate is connected to one end of the first fuel circuit self-generating pressure solenoid valve and one end of the second fuel circuit self-generating pressure solenoid valve. The other end is connected to the first fuel circuit self-generating pressure orifice plate, the second fuel circuit self-generating pressure orifice plate, the pressure inlet of the fuel tank, the first fuel circuit pressure replenishment orifice plate, and the second fuel circuit pressure replenishment orifice plate. One end of the oxidant pump inlet valve is connected to the first outlet of the oxidant tank, and the other end of the oxidant pump inlet valve is connected to the oxidant circulation control valve. The oxidant circulation control valve is connected to the oxidant circulation pump and the oxidant branch supply control valve. The oxidant branch supply control valve is connected to one end of the oxidant circulation pump and the oxidant pressure stabilizing valve. The other end of the oxidant pressure stabilizing valve is connected to the oxidant energy dissipator. The oxidizer energy dissipator is connected to the top return port of the oxidizer tank; the oxidizer circulation pump is connected to the oxidizer heat exchanger; the oxidizer heat exchanger is connected to the oxidizer Joule-Thomson throttling expansion valve and the second outlet of the oxidizer tank; the oxidizer Joule-Thomson throttling expansion valve is connected to the third outlet of the oxidizer tank; one end of the fuel pump inlet valve is connected to the first outlet of the fuel tank, and the other end of the fuel pump inlet valve is connected to the fuel circulation control valve; the fuel circulation control valve is connected to the fuel circulation pump and the fuel branch supply control valve; the fuel branch supply control valve is connected to one end of the fuel circulation pump and the fuel pressure regulating valve; the other end of the fuel pressure regulating valve is connected to the fuel energy dissipator; the fuel energy dissipator is connected to the top return port of the fuel tank; the fuel circulation pump is connected to the fuel heat exchanger.The fuel heat exchanger is communicated with the second liquid outlet of the fuel Joule-Thomson throttling expansion valve and the fuel storage tank; the fuel Joule-Thomson throttling expansion valve is communicated with the third liquid outlet of the fuel storage tank; the attitude control engine subsystem comprises: a plurality of attitude control engines; each attitude control engine comprises: an attitude control thrust chamber, and an oxidizer control valve, a fuel control valve and an attitude control thrust chamber igniter arranged on the attitude control thrust chamber; the oxidizer control valve of each attitude control engine is communicated with the other end of the oxidizer pressure stabilizing valve and the oxidizer energy absorber through a first pipeline, and the oxidizer control valves of each attitude control engine are in mutual communication relationship; the oxidizer control valve of each attitude control engine is communicated with one end of the oxidizer pressure stabilizing valve and the oxidizer branch supply control valve through a second pipeline; the fuel control valve of each attitude control engine is communicated with the other end of the fuel pressure stabilizing valve and the fuel energy absorber through a third pipeline, and the fuel control valves of each attitude control engine are in mutual communication relationship; the fuel control valve of each attitude control engine is communicated with one end of the fuel pressure stabilizing valve and the fuel branch supply control valve through a fourth pipeline.

[0009] As the above, wherein the oxidizer storage tank comprises: an oxidizer storage tank body and an upper convex oxidizer partition plate, the oxidizer partition plate is arranged in the oxidizer storage tank body, and divides the oxidizer storage tank body into an upper oxidizer cabin body and a lower oxidizer cabin body; a plurality of screen windows are arranged at the edge of the oxidizer partition plate; in a microgravity environment, the pressurized gas in the upper oxidizer cabin body is prevented from entering the lower oxidizer cabin body through the screen window, and in a positive overload environment, the oxidizer in the upper oxidizer cabin body flows into the lower oxidizer cabin body; a central part of the oxidizer partition plate is provided with an oxidizer storage tank check valve, the gas in the lower oxidizer cabin body is discharged through the oxidizer storage tank check valve, and the oxidizer is refilled; the pressurizing port of the oxidizer storage tank and the top backflow port of the oxidizer storage tank are arranged on the upper oxidizer cabin body; the pressurizing port of the oxidizer storage tank is provided with an oxidizer gas diffuser; the upper oxidizer cabin body is further provided with an oxidizer discharge port and an oxidizer pressure measuring port; the oxidizer discharge port is connected with an oxidizer overflow valve; the oxidizer pressure measuring port is connected with an oxidizer storage tank pressure sensor; the first liquid outlet of the oxidizer storage tank, the second liquid outlet of the oxidizer storage tank, the third liquid outlet of the oxidizer storage tank, the oxidizer filling port and the bottom backflow port of the oxidizer storage tank are arranged on the lower oxidizer cabin body; the lower oxidizer cabin body is provided with an oxidizer channel type management device for realizing non-gas trapping supply of the oxidizer; wherein the structure of the fuel storage tank is the same as that of the oxidizer storage tank.

[0010] As the above, wherein the working mode of the low-temperature upper stage power system comprises: a precooling mode, a pressurizing mode, a working mode and a standby mode; wherein the precooling mode comprises: a main engine precooling mode and an attitude control engine precooling mode; the pressurizing mode comprises: a main engine pressurizing mode and an attitude control engine pressurizing mode; the working mode comprises: a main engine working mode and an attitude control engine working mode.

[0011] The above, wherein, the main engine precooling mode, during the upper stage filling oxidizer, the oxidizer circulating pump, the oxidizer circulation control valve, the oxidizer branch supply control valve and the oxidizer Joule-Thomson throttle expansion valve are in the closed state, the oxidizer pump front valve is in the open state, the oxidizer precooling reflux valve switches to the discharge precooling state; 10 min before firing, the oxidizer pump front valve is closed, the oxidizer circulation control valve and the oxidizer circulating pump are opened, and the oxidizer flows out from the oxidizer tank, then, under the drive of the oxidizer circulating pump, sequentially passes through the oxidizer circulation control valve, the oxidizer pump and the oxidizer precooling reflux valve, and then returns to the oxidizer tank through the bottom reflux port of the oxidizer tank; during the upper stage flight, 10 min before the main engine ignition, the oxidizer pump front valve is closed, the oxidizer circulation control valve and the oxidizer circulating pump are opened, the oxidizer flows out from the oxidizer tank, then, under the drive of the oxidizer circulating pump, sequentially passes through the oxidizer circulation control valve, the oxidizer pump and the oxidizer precooling reflux valve, and then returns to the oxidizer tank through the bottom reflux port of the oxidizer tank, realizing circulating precooling.

[0012] The above, wherein, the attitude control engine precooling mode, during the upper stage flight, 20 min before the attitude control engine ignition, the oxidizer branch supply control valve and the oxidizer circulating pump are opened, the oxidizer flows out from the oxidizer tank, passes through the oxidizer control valve, and then returns to the oxidizer tank through the top reflux port of the oxidizer tank; the fuel branch supply control valve and the fuel circulating pump are opened, the fuel flows out from the fuel tank, passes through the fuel control valve, and then returns to the fuel tank through the top reflux port of the fuel tank.

[0013] The above, wherein, the main engine working mode, 2 min before the main engine ignition, the oxidizer circulation control valve and the oxidizer circulating pump are closed, the fuel circulation control valve and the fuel circulating pump are closed, and the oxidizer pump front valve and the fuel pump front valve are opened; after the upper stage control system issues the main engine ignition instruction, the starting cylinder control valve is opened, the high-pressure gas in the starting cylinder blows the turbine to rotate, the oxidizer auxiliary valve, the fuel auxiliary valve and the gas generator igniter are opened according to the preset first time sequence, the gas generator is ignited, the oxidizer main valve, the fuel main valve and the main thrust chamber igniter are opened according to the preset second time sequence, and the main thrust chamber is ignited.

[0014] The above, wherein, the attitude control engine working mode, after the upper stage control system issues the attitude control engine ignition instruction, the oxidizer control valve, the fuel control valve and the attitude control thrust chamber igniter are opened according to the preset third time sequence, and the attitude control thrust chamber is ignited.

[0015] The upper stage control system obtains the current pressure of the oxidizer tank through the oxidizer tank pressure sensor by using a two-out-of-three redundant voting architecture; obtains the current pressure of the fuel tank through the fuel tank pressure sensor by using a two-out-of-three redundant voting architecture; when the current pressure of the oxidizer tank is lower than the preset lower limit of the first oxidizer tank pressure band, sequentially opens the first oxygen road pressure compensation solenoid valve and the second oxygen road pressure compensation solenoid valve to pressurize; when the pressurized pressure of the oxidizer tank is higher than the preset upper limit of the first oxidizer tank pressure band, sequentially closes the first oxygen road pressure compensation solenoid valve and the second oxygen road pressure compensation solenoid valve; after the main engine of the upper stage power system works, and when the current pressure of the oxidizer tank is lower than the preset lower limit of the second oxidizer tank pressure band, sequentially opens the first oxygen road self-pressurization solenoid valve and the second oxygen road self-pressurization solenoid valve to pressurize; when the pressurized pressure of the oxidizer tank is higher than the preset upper limit of the second oxidizer tank pressure band, sequentially closes the first oxygen road self-pressurization solenoid valve and the second oxygen road self-pressurization solenoid valve; when the current pressure of the oxidizer tank is higher than the preset opening pressure of the oxidizer relief valve, opens the oxidizer relief valve to exhaust; after the upper stage power system takes off with the base stage rocket, when the current pressure of the fuel tank is lower than the preset lower limit of the first fuel tank pressure band, sequentially opens the first fuel road pressure compensation solenoid valve and the second fuel road pressure compensation solenoid valve to pressurize; when the pressurized pressure of the fuel tank is higher than the preset upper limit of the first fuel tank pressure band, sequentially closes the first fuel road pressure compensation solenoid valve and the second fuel road pressure compensation solenoid valve; after the main engine of the upper stage power system works, and when the current pressure of the fuel tank is lower than the preset lower limit of the second fuel tank pressure band, sequentially opens the first fuel road self-pressurization solenoid valve and the second fuel road self-pressurization solenoid valve to pressurize; when the pressurized pressure of the fuel tank is higher than the preset upper limit of the second fuel tank pressure band, sequentially closes the first fuel road self-pressurization solenoid valve and the second fuel road self-pressurization solenoid valve; when the current pressure of the fuel tank is higher than the preset opening pressure of the fuel relief valve, opens the fuel relief valve to exhaust.

[0016] In the boost mode of the attitude control engine, the oxidizer and fuel of the attitude control engine are pressurized by opening the oxidizer branch supply control valve, the oxidizer circulating pump, the fuel branch supply control valve and the fuel circulating pump.

[0017] The upper stage control system obtains the current pressure of the oxidizer tank through the oxidizer tank pressure sensor by using a two-out-of-three redundant voting architecture; obtains the current pressure of the fuel tank through the fuel tank pressure sensor by using a two-out-of-three redundant voting architecture; when the current pressure of the oxidizer tank is higher than the preset upper limit of the third oxidizer tank pressure band, the oxidizer circulating pump and the oxidizer branch supply control valve are opened, and the oxidizer flows through the top return port of the oxidizer tank and the oxidizer energy absorber to realize the temperature and pressure reduction of the air pillow area of the oxidizer tank; when the current pressure of the oxidizer tank reaches the preset lower limit of the third oxidizer tank pressure band, the oxidizer circulating pump is closed; when the current pressure of the oxidizer tank is higher than the preset upper limit of the fourth oxidizer tank pressure band, the oxidizer circulating pump, the oxidizer branch supply control valve and the oxidizer Joule-Thomson throttling expansion valve are opened at the same time, a part of the oxidizer is cooled by the oxidizer heat exchanger under the drive of the oxidizer circulating pump, the cooled liquid part is re-injected into the oxidizer tank through the top return port of the oxidizer tank and the oxidizer energy absorber to realize the temperature and pressure reduction of the air pillow area of the oxidizer tank, and another part of the oxidizer is expanded and cooled by the oxidizer Joule-Thomson throttling expansion valve and is discharged in the form of gas as the cold source of the oxidizer heat exchanger; when the current pressure of the oxidizer tank is lower than the preset upper limit of the third oxidizer tank pressure band, the oxidizer Joule-Thomson throttling expansion valve is closed; when the current pressure of the fuel tank is higher than the preset upper limit of the third fuel tank pressure band, the fuel circulating pump and the fuel branch supply control valve are opened, and the fuel flows through the top return port of the fuel tank and the fuel energy absorber to realize the temperature and pressure reduction of the air pillow area of the fuel tank; when the current pressure of the fuel tank is higher than the preset upper limit of the fourth fuel tank pressure band, the fuel circulating pump, the fuel branch supply control valve and the fuel Joule-Thomson throttling expansion valve are opened at the same time, a part of the fuel is cooled by the fuel heat exchanger under the drive of the fuel circulating pump, the cooled liquid part is re-injected into the fuel tank through the top return port of the fuel tank and the fuel energy absorber to realize the temperature and pressure reduction of the air pillow area of the fuel tank, and another part of the fuel is expanded and cooled by the fuel Joule-Thomson throttling expansion valve and is discharged in the form of gas as the cold source of the fuel heat exchanger; when the current pressure of the fuel tank is lower than the preset upper limit of the third fuel tank pressure band, the fuel Joule-Thomson throttling expansion valve is closed.

[0018] The beneficial effects realized by the present application are as follows:

[0019] (1) The low-temperature upper stage power system of the present application uses a unified pressurized delivery subsystem to realize the propellant (for example: liquid oxygen, liquid methane) supply of the main engine and the attitude control engine, which reduces the types of propellants and components and simplifies the use and maintenance process compared with the traditional upper stage power system.

[0020] (2) The low-temperature upper stage power system of the present application adopts a unified propellant tank (i.e., oxidizer tank, fuel tank) for the main engine and the attitude control engine, and through the combination of an electric pump (i.e., oxidizer pump, fuel pump) and a pressure stabilizing valve (i.e., oxidizer pressure stabilizing valve, fuel pressure stabilizing valve), the unused propellant is recycled, thereby improving the utilization rate of the propellant.

[0021] (3) The low-temperature upper stage power system of the present application adopts a circulating pump (i.e., oxidizer circulating pump, fuel circulating pump), which can simultaneously realize the circulation pre-cooling of the main engine and the pre-cooling and propellant supply of the attitude control engine.

[0022] (4) Compared with the traditional low-temperature upper stage power system, the low-temperature upper stage power system of the present application simplifies the thermal management between the low-temperature main propulsion system (i.e., main engine subsystem) and the normal-temperature attitude control power system (i.e., attitude control engine subsystem).

[0023] (5) The low-temperature upper stage power system of the present application adopts a low-pressure tank (i.e., oxidizer tank, fuel tank) to realize the storage of the propellant of the low-temperature main propulsion system and the normal-temperature attitude control power system, thereby reducing the dry weight of the tank and the total weight of the low-temperature upper stage power system compared with the traditional upper stage power system.

[0024] (6) The low-pressure tank (i.e., oxidizer tank, fuel tank) in the low-temperature upper stage power system of the present application adopts a compartment structure (i.e., upper oxidizer compartment, lower oxidizer compartment, upper fuel compartment, and lower fuel compartment), a middle partition plate (i.e., oxidizer middle partition plate, fuel middle partition plate) is provided with a partition plate window around, a one-way valve (i.e., oxidizer tank one-way valve, fuel tank one-way valve) is arranged in the middle, and a propellant management device (i.e., channel type oxidizer management device, channel type fuel management device) is arranged in the lower compartment (i.e., lower oxidizer compartment, lower fuel compartment), thereby realizing the non-air-entrapped propellant supply of the main engine and the attitude control engine. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments described in the present application, and other drawings can also be obtained by those skilled in the art according to these drawings.

[0026] Figure 1 Structure schematic diagram of an embodiment of the low-temperature upper stage power system;

[0027] Figure 2 Structure schematic diagram of an embodiment of the oxidizer tank;

[0028] Figure 3Schematic diagram of an embodiment for a main engine boost mode

[0029] Figure 4 Schematic diagram of an embodiment for a main engine pre-cool mode

[0030] Figure 5 Schematic diagram of an embodiment for a main engine operation mode

[0031] Figure 6 Schematic diagram of an embodiment for an attitude control engine boost mode

[0032] Figure 7 Schematic diagram of an embodiment for an attitude control engine pre-cool mode. DETAILED DESCRIPTION

[0033] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, instead of all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0034] As shown in Figures 1-7 The present application provides a low-temperature upper stage power system, which comprises: an outlet of a gas cylinder 1 of a boost delivery subsystem is in communication with one end of a first oxygen route pressure compensation electromagnetic valve 2, the other end of the first oxygen route pressure compensation electromagnetic valve 2 is in communication with a first oxygen route pressure compensation orifice plate 6, and the first oxygen route pressure compensation orifice plate 6 is in communication with a boost inlet 211 of an oxidant storage tank 20; the outlet of the gas cylinder 1 is in communication with one end of a second oxygen route pressure compensation electromagnetic valve 3, one end of the second oxygen route pressure compensation electromagnetic valve 3 is in communication with one end of the first oxygen route pressure compensation electromagnetic valve 2, the other end of the second oxygen route pressure compensation electromagnetic valve 3 is in communication with a second oxygen route pressure compensation orifice plate 7, and the second oxygen route pressure compensation orifice plate 7 is in communication with the first oxygen route pressure compensation orifice plate 6 and the boost inlet 211 of the oxidant storage tank 20. The outlet of the gas cylinder 1 is in communication with one end of a first fuel route pressure compensation electromagnetic valve 4, the other end of the first fuel route pressure compensation electromagnetic valve 4 is in communication with a first fuel route pressure compensation orifice plate 8, and the first fuel route pressure compensation orifice plate 8 is in communication with a boost inlet of a fuel storage tank 21; the outlet of the gas cylinder 1 is in communication with one end of a second fuel route pressure compensation electromagnetic valve 5, one end of the second fuel route pressure compensation electromagnetic valve 5 is in communication with one end of the first fuel route pressure compensation electromagnetic valve 4, the other end of the second fuel route pressure compensation electromagnetic valve 5 is in communication with a second fuel route pressure compensation orifice plate 9, and the second fuel route pressure compensation orifice plate 9 is in communication with the first fuel route pressure compensation orifice plate 8 and the boost inlet of the fuel storage tank 21.

[0035] The oxidizer tank 20 is provided with at least three oxidizer tank pressure sensors 24, an oxidizer relief valve 22 and an oxidizer filling port 206; the fuel tank 21 is provided with at least three fuel tank pressure sensors 25, a fuel relief valve 23 and a fuel filling port. The specific number of the oxidizer tank pressure sensors 24 and the fuel tank pressure sensors 25 is set according to the actual situation, and the application preferably is three.

[0036] The bottom return port 205 of the oxidizer tank 20 is in communication with the first outlet of the oxidizer pre-cooling return valve 42, the inlet of the oxidizer pre-cooling return valve 42 is in communication with the first outlet of the oxidizer main valve 40; the second outlet of the oxidizer main valve 40 is in communication with the main thrust chamber 44 of the main engine subsystem; the inlet of the oxidizer main valve 40 is in communication with the oxidizer pump 34, the oxidizer auxiliary valve 37 and the oxidizer evaporator 45; the oxidizer auxiliary valve 37 is in communication with the gas generator 39, the oxidizer evaporator 45 and the oxidizer pump 34; the oxidizer pump 34 is in communication with the oxidizer evaporator 45, the oxidizer pump front valve 32 and the oxidizer circulation control valve 30; the main thrust chamber 44 is provided with a main thrust chamber igniter 54; the main thrust chamber 44 is in communication with the second outlet of the fuel main valve 41, the first outlet of the fuel main valve 41 is in communication with the inlet of the fuel pre-cooling return valve 43, the first outlet of the fuel pre-cooling return valve 43 is in communication with the bottom return port of the fuel tank 21; the inlet of the fuel main valve 41 is in communication with the fuel pump 35, the fuel auxiliary valve 38 and the fuel evaporator 46; the fuel auxiliary valve 38 is in communication with the gas generator 39, the fuel evaporator 39 and the fuel pump 35; the fuel pump 35 is in communication with the fuel evaporator 46, the fuel pump front valve 33 and the fuel circulation control valve 31; the gas generator 39 is in communication with the turbine 36; the turbine 36 is in communication with the starting gas cylinder control valve 53, the starting gas cylinder control valve 53 is in communication with the starting gas cylinder 52; the gas generator 39 is provided with a gas generator igniter 55.

[0037] The oxidant evaporator 45 is communicated with one end of the first oxygen route self-boosting electromagnetic valve 10, the other end of the first oxygen route self-boosting electromagnetic valve 10 is communicated with the first oxygen route self-boosting orifice plate 14, the first oxygen route self-boosting orifice plate 14 is communicated with the boost port 211 of the oxidant storage tank 20, the first oxygen route pressure compensation orifice plate 6 and the second oxygen route pressure compensation orifice plate 7; the oxidant evaporator 45 is communicated with one end of the second oxygen route self-boosting electromagnetic valve 11, one end of the second oxygen route self-boosting electromagnetic valve 11 is communicated with one end of the first oxygen route self-boosting electromagnetic valve 10, the other end of the second oxygen route self-boosting electromagnetic valve 11 is communicated with the second oxygen route self-boosting orifice plate 15, the second oxygen route self-boosting orifice plate 15 is communicated with the boost port 211 of the oxidant storage tank 20, the first oxygen route self-boosting orifice plate 14, the first oxygen route pressure compensation orifice plate 6 and the second oxygen route pressure compensation orifice plate 7; the oxidant evaporator 45 is communicated with the third oxygen route self-boosting orifice plate 16, one end of the third oxygen route self-boosting orifice plate 16 is communicated with one end of the first oxygen route self-boosting electromagnetic valve 10 and one end of the second oxygen route self-boosting electromagnetic valve 11, the other end of the third oxygen route self-boosting orifice plate 16 is communicated with the first oxygen route self-boosting orifice plate 14, the second oxygen route self-boosting orifice plate 15, the boost port 211 of the oxidant storage tank 20, the first oxygen route pressure compensation orifice plate 6 and the second oxygen route pressure compensation orifice plate 7. The fuel evaporator 46 is communicated with one end of the first fuel route self-boosting electromagnetic valve 12, the other end of the first fuel route self-boosting electromagnetic valve 12 is communicated with the first fuel route self-boosting orifice plate 17, the first fuel route self-boosting orifice plate 17 is communicated with the boost port of the fuel storage tank 21, the first fuel route pressure compensation orifice plate 8 and the second fuel route pressure compensation orifice plate 9; the fuel evaporator 46 is communicated with one end of the second fuel route self-boosting electromagnetic valve 13, one end of the second fuel route self-boosting electromagnetic valve 13 is communicated with one end of the first fuel route self-boosting electromagnetic valve 12, the other end of the second fuel route self-boosting electromagnetic valve 13 is communicated with the second fuel route self-boosting orifice plate 18, the second fuel route self-boosting orifice plate 18 is communicated with the boost port of the fuel storage tank 21, the first fuel route self-boosting orifice plate 17, the first fuel route pressure compensation orifice plate 8 and the second fuel route pressure compensation orifice plate 9; the fuel evaporator 46 is communicated with the third fuel route self-boosting orifice plate 19, one end of the third fuel route self-boosting orifice plate 19 is communicated with one end of the first fuel route self-boosting electromagnetic valve 12 and one end of the second fuel route self-boosting electromagnetic valve 13, the other end of the third fuel route self-boosting orifice plate 19 is communicated with the first fuel route self-boosting orifice plate 17, the second fuel route self-boosting orifice plate 18, the boost port of the fuel storage tank 21, the first fuel route pressure compensation orifice plate 8 and the second fuel route pressure compensation orifice plate 9.

[0038] One end of the oxidizer pump pre-valve 32 is communicated with the first liquid outlet 207 of the oxidizer tank 20, and the other end of the oxidizer pump pre-valve 32 is communicated with the oxidizer circulation control valve 30; the oxidizer circulation control valve 30 is communicated with the oxidizer circulation pump 28 and the oxidizer branch supply control valve 47; the oxidizer branch supply control valve 47 is communicated with the oxidizer circulation pump 28 and one end of the oxidizer pressure stabilizing valve 26; the other end of the oxidizer pressure stabilizing valve 26 is communicated with the oxidizer energy absorber 214; the oxidizer energy absorber 214 is communicated with the top reflux port 213 of the oxidizer tank; the oxidizer circulation pump 28 is communicated with the oxidizer heat exchanger 58; the oxidizer heat exchanger 58 is communicated with the oxidizer Joule-Thomson throttling expansion valve 57 and the second liquid outlet 208 of the oxidizer tank 20; the oxidizer Joule-Thomson throttling expansion valve 57 is communicated with the third liquid outlet 215 of the oxidizer tank 20. One end of the fuel pump pre-valve 33 is communicated with the first liquid outlet of the fuel tank 21, and the other end of the fuel pump pre-valve 33 is communicated with the fuel circulation control valve 31; the fuel circulation control valve 31 is communicated with the fuel circulation pump 29 and the fuel branch supply control valve 48; the fuel branch supply control valve 48 is communicated with the fuel circulation pump 29 and one end of the fuel pressure stabilizing valve 27; the other end of the fuel pressure stabilizing valve 27 is communicated with the fuel energy absorber; the fuel energy absorber is communicated with the top reflux port of the fuel tank 21; the fuel circulation pump 29 is communicated with the fuel heat exchanger 60; the fuel heat exchanger 60 is communicated with the fuel Joule-Thomson throttling expansion valve 59 and the second liquid outlet of the fuel tank 21; the fuel Joule-Thomson throttling expansion valve 59 is communicated with the third liquid outlet of the fuel tank 21. The attitude control engine subsystem comprises: a plurality of attitude control engines; each attitude control engine comprises: an attitude control thrust chamber 51, and the attitude control thrust chamber 51 is provided with an oxidizer control valve 49, a fuel control valve 50 and an attitude control thrust chamber igniter 56; the oxidizer control valve 49 of each attitude control engine is communicated with the other end of the oxidizer pressure stabilizing valve 26 and the oxidizer energy absorber 214 through a first pipeline, and the oxidizer control valves 49 of each attitude control engine are in a mutual communication relationship; the oxidizer control valve 49 of each attitude control engine is communicated with one end of the oxidizer pressure stabilizing valve 26 and the oxidizer branch supply control valve 47 through a second pipeline. The fuel control valve 50 of each attitude control engine is communicated with the other end of the fuel pressure stabilizing valve 27 and the fuel energy absorber through a third pipeline, and the fuel control valves 50 of each attitude control engine are in a mutual communication relationship; the fuel control valve 50 of each attitude control engine is communicated with one end of the fuel pressure stabilizing valve 27 and the fuel branch supply control valve 48 through a fourth pipeline.

[0039] Specifically, the main engine subsystem is composed of the oxidizer pump 34, the fuel pump 35, the turbine 36, the oxidizer sub-valve 37, the fuel sub-valve 38, the gas generator 39, the oxidizer main valve 40, the fuel main valve 41, the oxidizer pre-cooling return valve 42, the fuel pre-cooling return valve 43, the main thrust chamber 44, the oxidizer evaporator 45, the fuel evaporator 46, the starting gas cylinder 52, the starting gas cylinder control valve 53, the main thrust chamber igniter 54, and the gas generator igniter 55. The pressurization system in the pressurization delivery subsystem is composed of the cylinder 1, the first oxygen route pressure compensation solenoid valve 2, the second oxygen route pressure compensation solenoid valve 3, the first fuel route pressure compensation solenoid valve 4, the second fuel route pressure compensation solenoid valve 5, the first oxygen route pressure compensation orifice plate 6, the second oxygen route pressure compensation orifice plate 7, the first fuel route pressure compensation orifice plate 8, the second fuel route pressure compensation orifice plate 9, the first oxygen route self-generated pressure compensation solenoid valve 10, the second oxygen route self-generated pressure compensation solenoid valve 11, the first fuel route self-generated pressure compensation solenoid valve 12, the second fuel route self-generated pressure compensation solenoid valve 13, the first oxygen route self-generated pressure compensation orifice plate 14, the second oxygen route self-generated pressure compensation orifice plate 15, the third oxygen route self-generated pressure compensation orifice plate 16, the first fuel route self-generated pressure compensation orifice plate 17, the second fuel route self-generated pressure compensation orifice plate 18, and the third fuel route self-generated pressure compensation orifice plate 19. The delivery system in the pressurization delivery subsystem is composed of the oxidizer storage tank 20, the fuel storage tank 21, the oxidizer relief valve 22, the fuel relief valve 23, the oxidizer storage tank pressure sensor 24, the fuel storage tank pressure sensor 25, the oxidizer pressure stabilizing valve 26, the fuel pressure stabilizing valve 27, the oxidizer circulation pump 28, the fuel circulation pump 29, the oxidizer circulation control valve 30, the fuel circulation control valve 31, the oxidizer pump front valve 32, the fuel pump front valve 33, the oxidizer Joule-Thomson throttling expansion valve 57, the oxidizer heat exchanger 58, the fuel Joule-Thomson throttling expansion valve 59, the fuel heat exchanger 60, the oxidizer branch supply control valve 47, and the fuel branch supply control valve 48. The oxidizer evaporator 45 and the fuel evaporator 46 are externally heated by the exhaust gas discharged by the turbine 36. The present application realizes the propellant supply of the main engine and the attitude control engine through the unified pressurization delivery system, and realizes the recycling of the unused propellant through the combination of the electric pump and the pressure stabilizing valve, thereby improving the utilization rate of the propellant, simplifying the upper stage power system components, reducing the weight of the power system, and optimizing the use and maintenance requirements.

[0040] Further, the oxidizer main valve 40 and the fuel main valve 41 are both two-position three-way valves, which include one inlet and two outlets. The two outlets of the two-position three-way valve are respectively used for circulating return pre-cooling and supplying the main thrust chamber 44. The inlet is in communication with the propellant pump (i.e., the oxidizer pump 34 and the fuel pump 35). In the closed state of the two-position three-way valve, the first outlet of the two-position three-way valve is in communication with the inlet of the pre-cooling return valve (i.e., the oxidizer pre-cooling return valve 42 and the fuel pre-cooling return valve 43). In the open state of the two-position three-way valve, the second outlet of the two-position three-way valve is in communication with the main thrust chamber 44.

[0041] Further, the oxidizer precooling return valve 42 and the fuel precooling return valve 43 are both two-position three-way valves, which include one inlet and two outlets, the inlet is communicated with the first outlet of the propellant main valve (i.e. the oxidizer main valve 40, the fuel main valve 41), the two outlets of the two-position three-way valve are respectively used for circulating return precooling and discharging precooling, in the open state of the two-position three-way valve, the first outlet of the two-position three-way valve is communicated with the bottom return port of the tank (i.e. the bottom return port 205 of the oxidizer tank 20, the bottom return port of the fuel tank 21), in the closed state of the two-position three-way valve, the second outlet of the two-position three-way valve is communicated with the outside.

[0042] Further, the oxidizer control valve 49 and the fuel control valve 50 are both two-position three-way valves, which include one inlet and two outlets, the inlet is communicated with the propellant branch supply control valve (i.e. the oxidizer branch supply control valve 47, the fuel branch supply control valve 48), the two outlets of the two-position three-way valve are respectively used for circulating return precooling and supplying the attitude control thrust chamber 51, in the closed state of the two-position three-way valve, the first outlet of the two-position three-way valve is communicated with the top return port of the tank (i.e. the top return port 213 of the oxidizer tank 20, the top return port of the fuel tank 21), in the open state of the two-position three-way valve, the second outlet of the two-position three-way valve is communicated with the attitude control thrust chamber 51.

[0043] Specifically, the oxidizer from the first liquid outlet 207 of the oxidizer tank 20, after passing through the oxidizer pump front valve 32, is divided into three paths by the oxidizer pump 34, one path enters the gas generator 39 through the oxidizer auxiliary valve 37, one path enters the main thrust chamber 44 through the oxidizer main valve 40, and one path becomes a high-temperature gas after heat exchange with the exhaust gas of the turbine 36 through the oxidizer evaporator 45, and enters the oxidizer tank 20 for pressurization through the first oxygen path self-pressurization solenoid valve 10, the second oxygen path self-pressurization solenoid valve 11, the first oxygen path self-pressurization orifice plate 14, the second oxygen path self-pressurization orifice plate 15 and the third oxygen path self-pressurization orifice plate 16. The fuel from the first liquid outlet of the fuel tank 21, after passing through the fuel pump front valve 33, is divided into three paths by the fuel pump 35, one path enters the gas generator 39 through the fuel auxiliary valve 38, one path enters the main thrust chamber 44 through the fuel main valve 41, and one path becomes a high-temperature gas after heat exchange with the exhaust gas of the turbine 36 through the fuel evaporator 46, and enters the fuel tank 21 for pressurization through the first fuel path self-pressurization solenoid valve 12, the second fuel path self-pressurization solenoid valve 13, the first fuel path self-pressurization orifice plate 17, the second fuel path self-pressurization orifice plate 18 and the third fuel path self-pressurization orifice plate 19.

[0044] The oxidizer from the second outlet 208 of the oxidizer tank 20, through the oxidizer heat exchanger 58 and the oxidizer circulating pump 28, is divided into two paths, one path through the oxidizer circulating control valve 30 for the pre-cooling of the main engine; the other path through the oxidizer branch supply control valve 47 is divided into two paths, one path delivers the oxidizer to the front of the oxidizer control valve 49, the other path through the oxidizer pressure stabilizing valve 26 into the top return port 213 of the oxidizer tank 20. The fuel from the second outlet of the fuel tank 21, through the fuel heat exchanger 60 and the fuel circulating pump 29, is divided into two paths, one path through the fuel circulating control valve 31 for the pre-cooling of the main engine; the other path through the fuel branch supply control valve 48 is divided into two paths, one path delivers the fuel to the front of the fuel control valve 50, the other path through the fuel pressure stabilizing valve 27 into the top return port of the fuel tank.

[0045] The oxidizer from the third outlet 215 of the oxidizer tank 20, through the oxidizer Joule-Thomson throttling expansion valve 57 and the oxidizer heat exchanger 58, is discharged to the outside. The fuel from the third outlet of the fuel tank 21, through the fuel Joule-Thomson throttling expansion valve 59 and the fuel heat exchanger 60, is discharged to the outside.

[0046] Further, as shown in Figure 1 and Figure 2 The oxidizer tank 20 includes: an oxidizer tank body and an upper convex oxidizer partition plate 201, the oxidizer partition plate 201 is arranged in the oxidizer tank body, and the oxidizer tank body is divided into an upper oxidizer cabin and a lower oxidizer cabin. A plurality of screen windows 202 are arranged at the edge of the oxidizer partition plate 201; in a microgravity environment, the pressurized gas in the upper oxidizer cabin is prevented from entering the lower oxidizer cabin through the screen window 202, and in a positive overload environment, the oxidizer in the upper oxidizer cabin flows into the lower oxidizer cabin. The middle part of the oxidizer partition plate 201 is provided with an oxidizer tank one-way valve 204, the gas in the lower oxidizer cabin is discharged through the oxidizer tank one-way valve 204, and the oxidizer is refilled. The pressurizing port 211 of the oxidizer tank 20 and the top return port 213 of the oxidizer tank 20 are arranged on the upper oxidizer cabin; the pressurizing port 211 of the oxidizer tank 20 is provided with an oxidizer gas diffuser 212; the upper oxidizer cabin is also provided with an oxidizer discharge port 210 and an oxidizer pressure measuring port 209; the oxidizer discharge port 210 is connected with an oxidizer overflow valve 22; the oxidizer pressure measuring port 209 is connected with an oxidizer tank pressure sensor 24; the first outlet 207 of the oxidizer tank 20, the second outlet 208 of the oxidizer tank 20, the third outlet 215 of the oxidizer tank 20, the oxidizer filling port 206 and the bottom return port 205 of the oxidizer tank 20 are arranged on the lower oxidizer cabin. The lower oxidizer cabin is provided with an oxidizer channel type management device 203 for realizing the non-air entrainment supply of the oxidizer.

[0047] Specifically, the first liquid outlet 207 of the oxidizer storage tank 20 is used for supplying oxidizer to the main thrust chamber 44, the second liquid outlet 208 of the oxidizer storage tank 20 is used for main engine pre-cooling return flow and supplying oxidizer to the attitude control thrust chamber 51, the third liquid outlet 215 of the oxidizer storage tank 20 is used for supplying oxidizer to the branch of the oxidizer Joule-Thomson throttle expansion valve 57, the bottom return port 205 of the oxidizer storage tank 20 is used for main engine pre-cooling return flow, and the oxidizer filling port 206 is used for filling the oxidizer storage tank 20. Taking the liquid oxygen-methane cryogenic upper stage power system as an example, the oxidizer is liquid oxygen.

[0048] Further, the specific number of the screen windows 202 of the oxidizer partition plate 201 is set according to actual conditions, and the application preferably has 4-6 screen windows 202 uniformly and separately arranged at the edge of the oxidizer partition plate 201.

[0049] Further, the fuel storage tank 21 comprises a fuel storage tank body and an upper convex fuel partition plate, the fuel partition plate is arranged in the fuel storage tank body, and the fuel storage tank body is divided into an upper fuel cabin body and a lower fuel cabin body. A plurality of screen windows are arranged at the edge of the fuel partition plate; in a microgravity environment, the screen windows prevent the pressurized gas in the upper fuel cabin body from entering the lower fuel cabin body, and in a positive overload environment, the fuel in the upper fuel cabin body flows into the lower fuel cabin body. A fuel storage tank check valve is arranged at the middle part of the fuel partition plate, the gas in the lower fuel cabin body is discharged through the fuel storage tank check valve, and fuel refilling is realized. The pressurizing port of the fuel storage tank 21 and the top return port of the fuel storage tank 21 are both arranged on the upper fuel cabin body; a fuel gas diffuser is arranged at the pressurizing port of the fuel storage tank 21; a fuel discharge port and a fuel pressure measuring port are further arranged on the upper fuel cabin body; the fuel discharge port is connected with a fuel relief valve 23; the fuel pressure measuring port is connected with a fuel storage tank pressure sensor 25; the first liquid outlet of the fuel storage tank 21, the second liquid outlet of the fuel storage tank 21, the third liquid outlet of the fuel storage tank 21, the fuel filling port and the bottom return port of the fuel storage tank 21 are all arranged on the lower fuel cabin body. The lower fuel cabin body is provided with a fuel channel type management device for realizing non-gas-trapping supply of fuel.

[0050] Specifically, the first liquid outlet of the fuel storage tank 21 is used for supplying fuel to the main thrust chamber 44, the second liquid outlet of the fuel storage tank 21 is used for main engine pre-cooling return flow and supplying fuel to the attitude control thrust chamber 51, the third liquid outlet of the fuel storage tank 21 is used for supplying fuel to the branch of the fuel Joule-Thomson throttle expansion valve 59, the bottom return port of the fuel storage tank 21 is used for main engine pre-cooling return flow, and the fuel filling port is used for filling the fuel storage tank 21. Taking the liquid oxygen-methane cryogenic upper stage power system as an example, the fuel is liquid methane.

[0051] Further, the specific number of the screen windows of the fuel partition plate is set according to actual conditions, and the application preferably has 4-6 screen windows uniformly and separately arranged at the edge of the fuel partition plate.

[0052] Further, the working modes of the low-temperature upper stage propulsion system include: pre-cooling mode, pressurization mode, working mode and standby mode; wherein, the pre-cooling mode includes: main engine pre-cooling mode and attitude control engine pre-cooling mode; the pressurization mode includes: main engine pressurization mode and attitude control engine pressurization mode; the working mode includes: main engine working mode and attitude control engine working mode.

[0053] Further, as shown in Figure 1 and Figure 4 , in the main engine pre-cooling mode, during the upper stage filling of oxidizer, the oxidizer circulating pump 28, the oxidizer circulating control valve 30, the oxidizer branch supply control valve 47 and the oxidizer Joule-Thomson throttling expansion valve 57 are all in the closed state, the oxidizer pump front valve 32 is in the open state, and the oxidizer pre-cooling return valve 42 is switched to the discharge pre-cooling state. 10 minutes before firing, the oxidizer pump front valve 32 is closed, the oxidizer circulating control valve 30 and the oxidizer circulating pump 28 are opened, and the oxidizer flows out from the oxidizer tank 20 and is returned to the oxidizer tank 20 through the bottom return port 205 of the oxidizer tank 20 after passing through the oxidizer circulating control valve 30, the oxidizer pump 34 and the oxidizer pre-cooling return valve 42 in turn under the drive of the oxidizer circulating pump 28. During the flight of the upper stage, 10 minutes before the main engine ignition, the oxidizer pump front valve 32 is closed, the oxidizer circulating control valve 30 and the oxidizer circulating pump 28 are opened, and the oxidizer flows out from the oxidizer tank 20 and is returned to the oxidizer tank 20 through the bottom return port 205 of the oxidizer tank 20 after passing through the oxidizer circulating control valve 30, the oxidizer pump 34 and the oxidizer pre-cooling return valve 42 in turn under the drive of the oxidizer circulating pump 28, realizing circulating pre-cooling.

[0054] Further, as shown in Figure 1 and Figure 7 , in the attitude control engine pre-cooling mode, during the flight of the upper stage, 20 minutes before the attitude control engine ignition, the oxidizer branch supply control valve 47 and the oxidizer circulating pump 28 are opened, the oxidizer flows out from the oxidizer tank 20 and is returned to the oxidizer tank 20 through the top return port 213 of the oxidizer tank 20 after passing through the oxidizer control valve 49; the fuel branch supply control valve 48 and the fuel circulating pump 29 are opened, and the fuel flows out from the fuel tank 21 and is returned to the fuel tank 21 through the top return port of the fuel tank 21 after passing through the fuel control valve 50.

[0055] Further, as shown in Figure 1 and Figure 3As shown, when the main engine is in the pressurization mode, after the upper stage power system takes off with the base stage rocket, the current pressure of the oxidizer tank 20 is obtained by the upper stage control system through the oxidizer tank pressure sensor 24 using a two-out-of-three redundant voting architecture; the current pressure of the fuel tank 21 is obtained by the fuel tank pressure sensor 25 using a two-out-of-three redundant voting architecture. When the current pressure of the oxidizer tank 20 is lower than the preset lower limit of the first oxidizer tank pressure band, the first oxygen route pressure compensation solenoid valve 2 and the second oxygen route pressure compensation solenoid valve 3 are opened in sequence to pressurize; when the pressurized pressure of the oxidizer tank 20 is higher than the preset upper limit of the first oxidizer tank pressure band, the first oxygen route pressure compensation solenoid valve 2 and the second oxygen route pressure compensation solenoid valve 3 are closed in sequence; when the main engine of the upper stage power system is working, and the current pressure of the oxidizer tank 20 is lower than the preset lower limit of the second oxidizer tank pressure band, the first oxygen route self-generating pressurization solenoid valve 10 and the second oxygen route self-generating pressurization solenoid valve 11 are opened in sequence to pressurize; when the pressurized pressure of the oxidizer tank 20 is higher than the preset upper limit of the second oxidizer tank pressure band, the first oxygen route self-generating pressurization solenoid valve 10 and the second oxygen route self-generating pressurization solenoid valve 11 are closed in sequence; when the current pressure of the oxidizer tank 20 is higher than the preset opening pressure of the oxidizer relief valve 22, the oxidizer relief valve 22 is opened to exhaust. After the upper stage power system takes off with the base stage rocket, when the current pressure of the fuel tank 21 is lower than the preset lower limit of the first fuel tank pressure band, the first fuel route pressure compensation solenoid valve 4 and the second fuel route pressure compensation solenoid valve 5 are opened in sequence to pressurize; when the pressurized pressure of the fuel tank 21 is higher than the preset upper limit of the first fuel tank pressure band, the first fuel route pressure compensation solenoid valve 4 and the second fuel route pressure compensation solenoid valve 5 are closed in sequence; when the main engine of the upper stage power system is working, and the current pressure of the fuel tank 21 is lower than the preset lower limit of the second fuel tank pressure band, the first fuel route self-generating pressurization solenoid valve 12 and the second fuel route self-generating pressurization solenoid valve 13 are opened in sequence to pressurize; when the pressurized pressure of the fuel tank 21 is higher than the preset upper limit of the second fuel tank pressure band, the first fuel route self-generating pressurization solenoid valve 12 and the second fuel route self-generating pressurization solenoid valve 13 are closed in sequence; when the current pressure of the fuel tank 21 is higher than the preset opening pressure of the fuel relief valve 23, the fuel relief valve 23 is opened to exhaust.

[0056] Specifically, the main engine is pressurized by self-generating pressurization and inert gas pressurization, but it is not limited to this method. The inert gas is stored in the gas cylinder 1, and the inert gas enters the pressurization port 211 of the oxidizer tank 20 through the first oxygen route pressure compensation solenoid valve 2 and the second oxygen route pressure compensation solenoid valve 3, the first oxygen route pressure compensation orifice plate 6 and the second oxygen route pressure compensation orifice plate 7 in sequence to pressurize the oxidizer tank 20; the inert gas enters the pressurization port of the fuel tank 21 through the first fuel route pressure compensation solenoid valve 4 and the second fuel route pressure compensation solenoid valve 5, the first fuel route pressure compensation orifice plate 8 and the second fuel route pressure compensation orifice plate 9 in sequence to pressurize the fuel tank 21.

[0057] Further, as shown in Figure 1 and Figure 6 , when the attitude control engine is in the pressurization mode, the pressurization of the oxidizer and fuel of the attitude control engine is realized by opening the oxidizer branch supply control valve 47, the oxidizer circulation pump 28, the fuel branch supply control valve 48 and the fuel circulation pump 29.

[0058] Further, as shown in Figure 1 and Figure 5 , when the main engine is in the working mode, 2 minutes before the main engine is ignited, the oxidizer circulation control valve 30 and the oxidizer circulation pump 28 are closed, the fuel circulation control valve 31 and the fuel circulation pump 29 are closed, the oxidizer pump front valve 32 and the fuel pump front valve 33 are opened; after the upper stage control system sends the main engine ignition instruction, the starting gas cylinder control valve 53 is opened, the high-pressure gas in the starting gas cylinder 52 blows the turbine 36 to rotate, the oxidizer auxiliary valve 37, the fuel auxiliary valve 38 and the gas generator igniter 55 are opened according to the pre-set first time sequence, the gas generator 39 takes over the ignition, the oxidizer main valve 40, the fuel main valve 41 and the main thrust chamber igniter 54 are opened according to the pre-set second time sequence, and the main thrust chamber 44 is ignited.

[0059] Further, when the attitude control engine is in the working mode, after the upper stage control system sends the attitude control engine ignition instruction, the oxidizer control valve 49, the fuel control valve 50 and the attitude control thrust chamber igniter 56 are opened according to the pre-set third time sequence, and the attitude control thrust chamber 51 is ignited.

[0060] Further, in standby mode, the upper stage control system obtains the current pressure of the oxidant tank 20 through the oxidant tank pressure sensor 24 by using a two-out-of-three redundancy voting architecture; and obtains the current pressure of the fuel tank through the fuel tank pressure sensor 25 by using a two-out-of-three redundancy voting architecture. When the current pressure of the oxidant tank 20 is higher than the preset upper limit of the third oxidant tank pressure band, the oxidant circulating pump 28 and the oxidant branch supply control valve 47 are opened, and the oxidant flows through the oxidant circulating pump 28 to realize the temperature and pressure reduction of the air pillow area of the oxidant tank 20 through the top return port 213 and the oxidant energy absorber 214 of the oxidant tank 20. When the current pressure of the oxidant tank 20 reaches the preset lower limit of the third oxidant tank pressure band, the oxidant circulating pump 28 is closed. When the current pressure of the oxidant tank 20 is higher than the preset upper limit of the fourth oxidant tank pressure band, the oxidant circulating pump 28, the oxidant branch supply control valve 47 and the oxidant Joule-Thomson throttling expansion valve 57 are opened at the same time, a part of the oxidant is cooled by the oxidant circulating pump 28 through the oxidant heat exchanger 58, and the cooled liquid part is injected into the oxidant tank 20 through the top return port 213 and the oxidant energy absorber 214 of the oxidant tank 20, so as to realize the temperature and pressure reduction of the air pillow area of the oxidant tank 20; another part of the oxidant is expanded and cooled through the oxidant Joule-Thomson throttling expansion valve 57, and is discharged in the form of gas as the cold source of the oxidant heat exchanger 58. When the current pressure of the oxidant tank 20 is lower than the preset upper limit of the third oxidant tank pressure band, the oxidant Joule-Thomson throttling expansion valve 57 is closed. When the current pressure of the fuel tank 21 is higher than the preset upper limit of the third fuel tank pressure band, the fuel circulating pump 29 and the fuel branch supply control valve 48 are opened, and the fuel flows through the fuel circulating pump 29 to realize the temperature and pressure reduction of the air pillow area of the fuel tank 21 through the top return port and the fuel energy absorber of the fuel tank 21. When the current pressure of the fuel tank 21 is higher than the preset upper limit of the fourth fuel tank pressure band, the fuel circulating pump 29, the fuel branch supply control valve 48 and the fuel Joule-Thomson throttling expansion valve 59 are opened at the same time, a part of the fuel is cooled by the fuel circulating pump 29 through the fuel heat exchanger 60, and the cooled liquid part is injected into the fuel tank 21 through the top return port and the fuel energy absorber of the fuel tank 21, so as to realize the temperature and pressure reduction of the air pillow area of the fuel tank 21; another part of the fuel is expanded and cooled through the fuel Joule-Thomson throttling expansion valve 59, and is discharged in the form of gas as the cold source of the fuel heat exchanger 60. When the current pressure of the fuel tank 21 is lower than the preset upper limit of the third fuel tank pressure band, the fuel Joule-Thomson throttling expansion valve 59 is closed.

[0061] Further, the specific number of gas cylinders 1 is set according to actual conditions, and the application preferably is three. The outlets of the three gas cylinders 1 are in a mutually communicating relationship.

[0062] The low-temperature upper stage power system of the application can be used for liquid oxygen and methane upper stage power system and liquid oxygen and kerosene upper stage power system.

[0063] The application achieves the following beneficial effects:

[0064] (1) The low-temperature upper stage power system of the application uses a unified pressurization and delivery subsystem to supply propellants (for example, liquid oxygen and liquid methane) for the main engine and the attitude control engine, thereby reducing the types of propellants and components and simplifying the use and maintenance process compared with the traditional upper stage power system.

[0065] (2) The low-temperature upper stage power system of the application uses a unified propellant tank (namely, oxidizer tank and fuel tank) for the main engine and the attitude control engine, and circulates and reuses unused propellants through the combination of electric pumps (namely, oxidizer pump and fuel pump) and pressure stabilizing valves (namely, oxidizer pressure stabilizing valve and fuel pressure stabilizing valve), thereby improving the utilization rate of propellants.

[0066] (3) The low-temperature upper stage power system of the application uses circulating pumps (namely, oxidizer circulating pump and fuel circulating pump) to simultaneously achieve the circulation precooling of the main engine and the precooling and propellant supply of the attitude control engine.

[0067] (4) The low-temperature upper stage power system of the application simplifies the thermal management between the low-temperature main propulsion system (namely, main engine subsystem) and the normal-temperature attitude control power system (namely, attitude control engine subsystem) compared with the traditional low-temperature upper stage power system.

[0068] (5) The low-temperature upper stage power system of the application uses low-pressure tanks (namely, oxidizer tank and fuel tank) to store the propellants of the low-temperature main propulsion system and the normal-temperature attitude control power system, thereby reducing the dry weight of the tank and the total weight of the low-temperature upper stage power system compared with the traditional upper stage power system.

[0069] (6) The low-pressure tanks (namely, oxidizer tank and fuel tank) in the low-temperature upper stage power system of the application use a compartment structure (namely, upper oxidizer compartment, lower oxidizer compartment, upper fuel compartment and lower fuel compartment), the middle partition plate (namely, oxidizer middle partition plate and fuel middle partition plate) is provided with partition plate windows around, a one-way valve (namely, oxidizer tank one-way valve and fuel tank one-way valve) is arranged in the middle, and the lower compartment (namely, lower oxidizer compartment and lower fuel compartment) is provided with a propellant management device (namely, channel type oxidizer management device and channel type fuel management device), thereby achieving the propellant supply without air trapping for the main engine and the attitude control engine.

[0070] While the preferred embodiments of the application have been described, additional variations and modifications can be made to these embodiments by those skilled in the art once they have the benefit of the foregoing description without departing from the spirit and scope of the application. Accordingly, it is intended that the scope of the application be governed solely by the appended claims and their equivalents. Obviously, many modifications and variations of this application are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A cryogenic upper stage power system, characterized in that, include: The outlet of the gas cylinder in the pressurization and delivery subsystem is connected to one end of the first oxygen path pressurization solenoid valve, the other end of which is connected to the first oxygen path pressurization orifice plate, which is connected to the pressurization port of the oxidant storage tank. The outlet of the gas cylinder is connected to one end of the second oxygen path pressurization solenoid valve, one end of which is connected to one end of the first oxygen path pressurization solenoid valve, and the other end of which is connected to the second oxygen path pressurization orifice plate. The second oxygen path pressurization orifice plate is connected to the pressurization port of the first oxygen path pressurization orifice plate and the pressurization port of the oxidant storage tank. The cylinder outlet is connected to one end of the first fuel line pressure-replenishing solenoid valve, the other end of the first fuel line pressure-replenishing solenoid valve is connected to the first fuel line pressure-replenishing orifice plate, and the first fuel line pressure-replenishing orifice plate is connected to the pressure-boosting port of the fuel storage tank; the cylinder outlet is connected to one end of the second fuel line pressure-replenishing solenoid valve, one end of the second fuel line pressure-replenishing solenoid valve is connected to one end of the first fuel line pressure-replenishing solenoid valve, the other end of the second fuel line pressure-replenishing solenoid valve is connected to the second fuel line pressure-replenishing orifice plate, and the second fuel line pressure-replenishing orifice plate is connected to the first fuel line pressure-replenishing orifice plate and the pressure-boosting port of the fuel storage tank; The oxidizer tank is equipped with at least three oxidizer tank pressure sensors, an oxidizer safety relief valve, and an oxidizer filling port; the fuel tank is equipped with at least three fuel tank pressure sensors, a fuel safety relief valve, and a fuel filling port. The bottom reflux port of the oxidant tank is connected to the first outlet of the oxidant precooling reflux valve, and the inlet of the oxidant precooling reflux valve is connected to the first outlet of the oxidant main valve; the second outlet of the oxidant main valve is connected to the main thrust chamber of the main engine subsystem; the inlet of the oxidant main valve is connected to the oxidant pump, the oxidant auxiliary valve, and the oxidant evaporator; the oxidant auxiliary valve is connected to the gas generator, the oxidant evaporator, and the oxidant pump; the oxidant pump is connected to the oxidant evaporator, the oxidant pump inlet valve, and the oxidant circulation control valve; the main thrust chamber is equipped with a main thrust chamber igniter; the main thrust chamber is connected to the fuel main valve. The second outlet is connected; the first outlet of the main fuel valve is connected to the inlet of the fuel precooling reflux valve; the first outlet of the fuel precooling reflux valve is connected to the bottom reflux port of the fuel tank; the inlet of the main fuel valve is connected to the fuel pump, the auxiliary fuel valve, and the fuel evaporator; the auxiliary fuel valve is connected to the gas generator, the fuel evaporator, and the fuel pump; the fuel pump is connected to the fuel evaporator, the fuel pump front valve, and the fuel circulation control valve; the gas generator is connected to the turbine; the turbine is connected to the starting gas cylinder control valve; the starting gas cylinder control valve is connected to the starting gas cylinder; a gas generator igniter is installed on the gas generator. The oxidant evaporator is connected to one end of the self-generating pressure solenoid valve in the first oxygen path, and the other end of the self-generating pressure solenoid valve in the first oxygen path is connected to the self-generating pressure orifice plate in the first oxygen path. The self-generating pressure orifice plate in the first oxygen path is connected to the pressure inlet of the oxidant storage tank, the pressure replenishment orifice plate in the first oxygen path, and the pressure replenishment orifice plate in the second oxygen path. The oxidant evaporator is connected to one end of the self-generating pressure solenoid valve in the second oxygen path, and one end of the self-generating pressure solenoid valve in the second oxygen path is connected to one end of the self-generating pressure solenoid valve in the first oxygen path. The other end of the self-generating pressure solenoid valve in the second oxygen path is connected to the self-generating pressure orifice plate in the second oxygen path. The second oxygen path self-generating pressure orifice plate is connected to the pressure inlet of the oxidant storage tank, the first oxygen path self-generating pressure orifice plate, the first oxygen path supplementary pressure orifice plate, and the second oxygen path supplementary pressure orifice plate; the oxidant evaporator is connected to the third oxygen path self-generating pressure orifice plate, one end of the third oxygen path self-generating pressure orifice plate is connected to one end of the first oxygen path self-generating pressure solenoid valve and one end of the second oxygen path self-generating pressure solenoid valve, and the other end of the third oxygen path self-generating pressure orifice plate is connected to the first oxygen path self-generating pressure orifice plate, the second oxygen path self-generating pressure orifice plate, the pressure inlet of the oxidant storage tank, the first oxygen path supplementary pressure orifice plate, and the second oxygen path self-generating pressure orifice plate. The oxygen circuit pressure-boosting orifice plate is connected; the fuel evaporator is connected to one end of the first fuel circuit self-generated pressure-boosting solenoid valve, and the other end of the first fuel circuit self-generated pressure-boosting solenoid valve is connected to the first fuel circuit self-generated pressure-boosting orifice plate. The first fuel circuit self-generated pressure-boosting orifice plate is connected to the pressure-boosting port of the fuel tank, the first fuel circuit pressure-boosting orifice plate, and the second fuel circuit pressure-boosting orifice plate; the fuel evaporator is connected to one end of the second fuel circuit self-generated pressure-boosting solenoid valve, and one end of the second fuel circuit self-generated pressure-boosting solenoid valve is connected to one end of the first fuel circuit self-generated pressure-boosting solenoid valve. The other end of the second fuel circuit self-generated pressure-boosting solenoid valve is connected to the second fuel circuit self-generated pressure-boosting orifice plate. The self-generating pressure orifice plate of the second combustion circuit is connected to the pressure inlet of the fuel tank, the self-generating pressure orifice plate of the first combustion circuit, the pressure supplement orifice plate of the first combustion circuit, and the pressure supplement orifice plate of the second combustion circuit; the fuel evaporator is connected to the self-generating pressure orifice plate of the third combustion circuit, one end of the self-generating pressure orifice plate of the third combustion circuit is connected to one end of the self-generating pressure solenoid valve of the first combustion circuit and one end of the self-generating pressure solenoid valve of the second combustion circuit, and the other end is connected to the self-generating pressure orifice plate of the first combustion circuit, the self-generating pressure orifice plate of the second combustion circuit, the pressure inlet of the fuel tank, the pressure supplement orifice plate of the first combustion circuit, and the pressure supplement orifice plate of the second combustion circuit; One end of the oxidant pump inlet valve is connected to the first outlet of the oxidant storage tank, and the other end is connected to the oxidant circulation control valve; the oxidant circulation control valve is connected to the oxidant circulation pump and the oxidant branch supply control valve; the oxidant branch supply control valve is connected to one end of the oxidant circulation pump and the oxidant pressure regulating valve; the other end of the oxidant pressure regulating valve is connected to the oxidant energy dissipator; the oxidant energy dissipator is connected to the top return port of the oxidant storage tank; the oxidant circulation pump is connected to the oxidant heat exchanger; the oxidant heat exchanger is connected to the oxidant Joule-Thomson throttling expansion valve and the second outlet of the oxidant storage tank; the oxidant Joule... - The Thomson throttling expansion valve is connected to the third outlet of the oxidizer tank; one end of the fuel pump pre-valve is connected to the first outlet of the fuel tank, and the other end of the fuel pump pre-valve is connected to the fuel circulation control valve; the fuel circulation control valve is connected to the fuel circulation pump and the fuel branch supply control valve; the fuel branch supply control valve is connected to one end of the fuel circulation pump and the fuel pressure regulating valve; the other end of the fuel pressure regulating valve is connected to the fuel energy dissipator; the fuel energy dissipator is connected to the top return port of the fuel tank; the fuel circulation pump is connected to the fuel heat exchanger; the fuel heat exchanger is connected to the fuel Joule-Thomson throttling expansion valve and the second outlet of the fuel tank. The fuel Joule-Thomson throttling expansion valve is connected to the third outlet of the fuel tank; The attitude control engine subsystem includes: multiple attitude control engines; each attitude control engine includes: an attitude control thrust chamber, on which an oxidizer control valve, a fuel control valve, and an attitude control thrust chamber igniter are installed; the oxidizer control valve of each attitude control engine is connected to the other end of the oxidizer pressure regulating valve and the oxidizer energy dissipator through a first pipeline, and the oxidizer control valves of each attitude control engine are interconnected; the oxidizer control valve of each attitude control engine is connected to one end of the oxidizer pressure regulating valve and the oxidizer branch supply control valve through a second pipeline; the fuel control valve of each attitude control engine is connected to the other end of the fuel pressure regulating valve and the fuel energy dissipator through a third pipeline, and the fuel control valves of each attitude control engine are interconnected; the fuel control valve of each attitude control engine is connected to one end of the fuel pressure regulating valve and the fuel branch supply control valve through a fourth pipeline.

2. The cryogenic upper stage power system according to claim 1, characterized in that, The oxidant storage tank includes: an oxidant storage tank body and an upwardly convex oxidant partition plate. The oxidant partition plate is disposed in the oxidant storage tank body, dividing the oxidant storage tank body into an upper oxidant chamber and a lower oxidant chamber. Multiple screen windows are provided at the edge of the oxidizer partition; under microgravity, the screen windows prevent pressurized gas in the upper oxidizer chamber from entering the lower oxidizer chamber, and under positive overload, the oxidizer in the upper oxidizer chamber flows into the lower oxidizer chamber. The middle part of the oxidant partition is equipped with an oxidant tank check valve. The gas in the lower oxidant chamber is discharged through the oxidant tank check valve to realize the refilling of oxidant. The pressurization port and the top reflux port of the oxidant storage tank are both located on the upper oxidant chamber. An oxidant gas diffuser is installed at the pressurization port of the oxidant storage tank. An oxidant discharge port and an oxidant pressure measuring port are also installed on the upper oxidant chamber. An oxidant relief valve is connected to the oxidant discharge port. An oxidant pressure sensor is connected to the oxidant storage tank pressure measuring port. The first liquid outlet, the second liquid outlet, the third liquid outlet, the oxidant filling port, and the bottom reflux port of the oxidant storage tank are all located on the lower oxidant chamber. The lower oxidizer compartment is equipped with an oxidizer channel management device for achieving a non-entrained oxidizer supply; The structure of the fuel tank is the same as that of the oxidizer tank.

3. The cryogenic upper stage power system according to claim 2, characterized in that, The operating modes of the cryogenic upper stage power system include: pre-cooling mode, boosting mode, operating mode, and standby mode; The pre-cooling modes include: main engine pre-cooling mode and attitude control engine pre-cooling mode; The boosting modes include: main engine boosting mode and attitude control engine boosting mode; The operating modes include: main engine operating mode and attitude control engine operating mode.

4. The cryogenic upper stage power system according to claim 3, characterized in that, During the main engine pre-cooling mode, when the upper stage is adding oxidizer, the oxidizer circulation pump, oxidizer circulation control valve, oxidizer branch supply control valve and oxidizer Joule-Thomson throttle expansion valve are all closed, the oxidizer pump inlet valve is open, and the oxidizer pre-cooling return valve is switched to the emission pre-cooling state. 10 minutes before firing, close the oxidizer pump inlet valve, open the oxidizer circulation control valve and the oxidizer circulation pump. After the oxidizer flows out of the oxidizer tank, it passes through the oxidizer circulation control valve, the oxidizer pump and the oxidizer pre-cooling reflux valve in sequence under the drive of the oxidizer circulation pump, and then flows back to the oxidizer tank through the bottom reflux port of the oxidizer tank. During upper stage flight, 10 minutes before main engine ignition, the oxidizer pump inlet valve is closed, and the oxidizer circulation control valve and oxidizer circulation pump are opened. After the oxidizer flows out of the oxidizer tank, it passes through the oxidizer circulation control valve, oxidizer pump and oxidizer pre-cooling return valve in sequence under the drive of the oxidizer circulation pump, and then flows back to the oxidizer tank through the bottom return port of the oxidizer tank to achieve circulation pre-cooling.

5. The cryogenic upper stage power system according to claim 3, characterized in that, In attitude control engine pre-cooling mode, during upper stage flight, 20 minutes before attitude control engine ignition, the oxidizer branch supply control valve and oxidizer circulation pump are opened. After the oxidizer flows out of the oxidizer tank, it passes through the oxidizer control valve and flows back to the oxidizer tank through the top return port. The fuel branch supply control valve and fuel circulation pump are opened. After the fuel flows out of the fuel tank, it passes through the fuel control valve and flows back to the fuel tank through the top return port.

6. The cryogenic upper stage power system according to claim 3, characterized in that, In main engine operating mode, 2 minutes before main engine ignition, the oxidizer circulation control valve and oxidizer circulation pump are closed, the fuel circulation control valve and fuel circulation pump are closed, and the oxidizer pump inlet valve and fuel pump inlet valve are opened. After the upper-level control system issues the main engine ignition command, the starter gas cylinder control valve is opened, the high-pressure gas in the starter gas cylinder blows the turbine to start rotating, and the oxidizer auxiliary valve, fuel auxiliary valve and gas generator igniter are opened according to the preset first sequence, and the gas generator takes over ignition. According to the preset second sequence, the oxidizer main valve, fuel main valve and main thrust chamber igniter are opened, and the main thrust chamber ignites.

7. The cryogenic upper stage power system according to claim 3, characterized in that, When the attitude control engine is in working mode, after the upper-level control system issues the attitude control engine ignition command, it opens the oxidizer control valve, fuel control valve and attitude control thrust chamber igniter according to the preset third timing sequence, and the attitude control thrust chamber is ignited.

8. The cryogenic upper stage power system according to claim 3, characterized in that, In the main engine pressurization mode, after the upper stage propulsion system takes off with the base stage rocket, the upper stage control system obtains the current pressure of the oxidizer tank through the oxidizer tank pressure sensor using a 2-out-of-3 redundancy voting architecture; and obtains the current pressure of the fuel tank through the fuel tank pressure sensor using a 2-out-of-3 redundancy voting architecture. When the current pressure of the oxidant tank is lower than the preset lower limit of the first oxidant tank pressure band, the first oxygen circuit pressure replenishing solenoid valve and the second oxygen circuit pressure replenishing solenoid valve are opened in sequence to increase the pressure. When the pressure of the oxidant tank after pressurization is higher than the preset upper limit of the first oxidant tank pressure band, the first oxygen circuit pressure replenishing solenoid valve and the second oxygen circuit pressure replenishing solenoid valve are closed in sequence. When the main engine of the upper-stage power system starts working, and the current pressure of the oxidizer tank is lower than the preset lower limit of the second oxidizer tank pressure band, the first oxygen circuit self-generating pressure solenoid valve and the second oxygen circuit self-generating pressure solenoid valve are opened sequentially to boost the pressure. When the boosted pressure of the oxidizer tank is higher than the preset upper limit of the second oxidizer tank pressure band, the first oxygen circuit self-generating pressure solenoid valve and the second oxygen circuit self-generating pressure solenoid valve are closed sequentially. When the current pressure of the oxidizer tank is higher than the preset oxidizer relief valve opening pressure, the oxidizer relief valve is opened to exhaust gas. After the upper stage propulsion system takes off with the base stage rocket, when the current pressure of the fuel tank is lower than the preset lower limit of the first fuel tank pressure band, the first and second fuel circuit pressure-boosting solenoid valves are opened sequentially to increase the pressure. When the pressurized pressure of the fuel tank is higher than the preset upper limit of the first fuel tank pressure band, the first and second fuel circuit pressure-boosting solenoid valves are closed sequentially. When the main engine of the upper stage propulsion system starts working, and the current pressure of the fuel tank is lower than the preset lower limit of the second fuel tank pressure band, the first and second fuel circuit self-generating pressure-boosting solenoid valves are opened sequentially to increase the pressure. When the pressurized pressure of the fuel tank is higher than the preset upper limit of the second fuel tank pressure band, the first and second fuel circuit self-generating pressure-boosting solenoid valves are closed sequentially. When the current pressure of the fuel tank is higher than the preset fuel overflow valve opening pressure, the fuel overflow valve is opened to release gas.

9. The cryogenic upper stage power system according to claim 3, characterized in that, In attitude control engine boost mode, the oxidizer and fuel of attitude control engine are boosted by opening the oxidizer branch supply control valve, oxidizer circulation pump, fuel branch supply control valve and fuel circulation pump.

10. The cryogenic upper stage power system according to claim 3, characterized in that, In standby mode, the upper-level control system obtains the current pressure of the oxidizer tank through the oxidizer tank pressure sensor using a 2-out-of-3 redundant voting architecture; and obtains the current pressure of the fuel tank through the fuel tank pressure sensor using a 2-out-of-3 redundant voting architecture. When the current pressure of the oxidant tank exceeds the preset upper limit of the third oxidant tank pressure band, the oxidant circulation pump and the oxidant branch supply control valve are opened. The oxidant flows through the oxidant circulation pump, through the top return port of the oxidant tank and the oxidant energy dissipator, to cool and depressurize the air cushion area of ​​the oxidant tank. When the current pressure of the oxidant tank reaches the preset lower limit of the third oxidant tank pressure band, the oxidant circulation pump is shut off. When the current pressure of the oxidant tank exceeds the preset upper limit of the fourth oxidant tank pressure band, the oxidant circulation pump, the oxidant branch supply control valve, and the oxidant... The Joule-Thomson throttling expansion valve allows a portion of the oxidant to be cooled by the oxidant heat exchanger under the drive of the oxidant circulation pump. The cooled liquid portion is then reinjected into the oxidant tank through the top return port and the oxidant energy dissipator, thus reducing the temperature and pressure in the gas pillow area of ​​the oxidant tank. Another portion of the oxidant expands and cools through the Joule-Thomson throttling expansion valve, serving as a cold source for the oxidant heat exchanger and being discharged as a gas. When the current pressure of the oxidant tank is lower than the preset upper limit of the third oxidant tank pressure band, the Joule-Thomson throttling expansion valve is closed. When the current pressure of the fuel tank is higher than the preset upper limit of the third fuel tank pressure band, the fuel circulation pump and the fuel branch supply control valve are opened. Fuel flows through the fuel circulation pump and passes through the top return port of the fuel tank and the fuel energy dissipator to cool and depressurize the fuel tank's air cushion area. When the current pressure of the fuel tank is higher than the preset upper limit of the fourth fuel tank pressure band, the fuel circulation pump, the fuel branch supply control valve, and the fuel Joule-Thomson throttling expansion valve are opened simultaneously. A portion of the fuel is cooled by the fuel heat exchanger driven by the fuel circulation pump. The cooled liquid portion is reinjected into the fuel tank through the top return port and the fuel energy dissipator to cool and depressurize the fuel tank's air cushion area. Another portion of the fuel expands and cools through the fuel Joule-Thomson throttling expansion valve, serving as a cold source for the fuel heat exchanger, and is discharged in gaseous form. When the current pressure of the fuel tank is lower than the preset upper limit of the third fuel tank pressure band, the fuel Joule-Thomson throttling expansion valve is closed.

Images