Satellite-borne long-life primary power switch circuit and control method thereof

Abstract

The invention provides a satellite-borne long-life primary power switch circuit and a control method thereof. The satellite-borne long-life primary power switch circuit comprises a surge suppression circuit, an on / off instruction interface circuit and a switch circuit, the surge suppression circuit is used for primary power supply surge suppression and primary power supply on-off control; the on / off instruction interface circuit realizes on-satellite instruction level conversion and electrical isolation through an optocoupler, and outputs an on signal Vopen and an off signal Vclose; the switching circuit receives an on signal Vopen and an off signal Vclose, controls the on-off of the surge suppression circuit and realizes power-on self-locking and power-off recovery; the surge suppression circuit is used for realizing power supply surge suppression and switching functions, and all the surge suppression circuits adopt semiconductor devices. According to the invention, a full-semiconductor device is adopted to realize power switching and surge suppression functions; the bottleneck of short service life of a mechanical contact of a relay is thoroughly solved, the long-service-life requirement of a high-resolution / hyperspectral remote sensing satellite for frequent switching is met, and a guarantee is provided for long-term in-orbit stable operation.

Description

Technical Field

[0001] The present invention relates to the technical field of primary power switch circuits, and in particular to a satellite-borne long-life primary power switch circuit and a control method thereof. Background Art

[0002] The primary power switching circuit is a critical component of satellite-borne products, directly impacting their operating mode, service life, reliability, and safety. Traditional atmospheric sounding payloads utilize a single switch per orbit, operating in sunny areas and shutting down in shadowed areas. Relays serve as power switch control devices. Relays, with their exceptional reliability and a nominal service life of 100,000 cycles, have long been the preferred choice for satellite-borne power switching. With the continuous advancement of remote sensing technology, high-resolution, hyperspectral remote sensing satellites are equipped with onboard synchronous atmospheric sounding payloads, operating synchronously with the main payload. Due to their large size, high power consumption, massive imaging data volumes, complex operating modes, and agile movements, high-resolution, hyperspectral remote sensing satellites place extremely high demands on resource utilization, including energy consumption, thermal control, storage, and switch life. These satellites require resource-optimized design and synchronization with atmospheric sounding equipment operating on the same platform, thus requiring the ability to operate on-orbit for short periods of time. This requires the primary power supply to possess long-life switching capabilities.

[0003] Patent publication CN113991610B discloses a satellite power on / off enable and undervoltage lockout circuit, comprising an input undervoltage protection circuit, an on / off signal isolation detection circuit, and a command judgment and execution circuit. The outputs of the input undervoltage protection circuit and the on / off signal isolation detection circuit are both connected to the input of the command judgment and execution circuit. This patent document only controls DC-DC converters, lacks surge suppression capabilities, and utilizes two transistors for control, resulting in increased component count, complex circuitry, and reduced reliability.

[0004] In the existing technology, if MOSFET is directly used to replace relays, although the life limit can be broken, two major problems need to be solved: surge suppression: the capacitive load charging current at the moment the MOSFET is turned on can easily cause a surge, threatening the safety of the device; command isolation and locking: it is necessary to achieve high-reliability isolation and conversion of on-board commands, and ensure that the state is self-locked after power-on and the command triggers precise power-off.

[0005] Therefore, it is urgent to design an all-solid-state power switching circuit that integrates long-life switching, surge suppression, command isolation and state locking to meet the core requirements of the new generation of satellite-borne payloads for high-frequency operation and high reliability. Summary of the Invention

[0006] In view of the defects in the prior art, the object of the present invention is to provide a satellite-borne long-life primary power switch circuit and a control method thereof.

[0007] According to the present invention, a satellite-borne long-life primary power switch circuit includes: a surge suppression circuit, an on / off command interface circuit, a switch circuit, and a self-locking circuit; the surge suppression circuit is used for primary power surge suppression and primary power on / off control; the on / off command interface circuit realizes on-board command level conversion and electrical isolation through an optical coupler, and outputs an on signal V open And off signal V close The switch circuit receives an open signal V open And off signal V close , controls the on and off of the surge suppression circuit and realizes power-on self-locking and power-off recovery; the surge suppression circuit is used to realize the power switch function, and all semiconductor devices are used.

[0008] Preferably, the surge suppression circuit includes a P-channel MOSFET Q1, a resistor R1 and a capacitor C1 connected in parallel, a resistor R2, and a resistor R3;

[0009] The resistor R1 and the capacitor C1 are connected in parallel and one end is connected to the power supply VCC in The other end is divided into two paths: one path is connected to the gate of P-channel MOSFET Q1 through resistor R2, and the other path is connected to the output end of the switch circuit through resistor R3; the source of P-channel MOSFET Q1 is connected to the power supply VCC in , the drain serves as the primary power output terminal.

[0010] Preferably, the on / off command interface circuit includes: a voltage regulator U1, a resistor R7, an optical coupler U2, a resistor R4, a resistor R6, a resistor R5 and an optical coupler U3;

[0011] The optocoupler U2 includes a transistor and a photodiode; the optocoupler U3 includes a transistor and a photodiode; the voltage regulator U1 is connected in series with the resistor R7 to generate the supply voltage for the collector of the transistor of the optocoupler U2; the open command is connected to the positive electrode of the photodiode of the optocoupler U2 through the resistor R4, the negative electrode of the photodiode of the optocoupler U2 is grounded, and the emitter of the transistor of the optocoupler U2 is pulled down by the resistor R6 to output the open signal V open The off command is connected to the positive electrode of the photodiode of the optocoupler U3 through the resistor R5, the negative electrode of the photodiode of the optocoupler U3 is grounded, and the collector of the transistor of the optocoupler U3 outputs the off signal V close .

[0012] Preferably, the switching circuit includes a transistor Q2, a diode D1, a diode D2, a resistor R8, a resistor R9, a resistor R10 and a voltage regulator U4;

[0013] The open signal V open Connect the base of transistor Q2 through diode D1, and the off signal V closeThe base of transistor Q2 is connected to the diode D2, and the base of transistor Q2 is grounded through resistor R8; the collector of transistor Q2 is connected to resistor R3 of the surge suppression circuit; the voltage regulator U4 is connected in series with resistor R10 to generate the working voltage VCC out , input the critical signal V through resistor R9 close node.

[0014] Preferably, the resistor R1, capacitor C1 and resistor R2 form an RC circuit, and the P-channel MOSFET Q1 controls the gate voltage rising rate of the P-channel MOSFET Q1 through the RC circuit, and controls the load current rising rate using the source-drain on-resistance, so as to realize surge suppression and power switching functions.

[0015] Preferably, the switch circuit triggers the P-channel MOSFET Q1 to turn on in response to an 80ms power-on command pulse, and maintains the on state after the pulse ends to achieve self-locking; and pulls down the gate voltage of the P-channel MOSFET Q1 in response to a shutdown command to achieve power off.

[0016] Preferably, the circuit further includes a redundant protection circuit, which includes a fuse F1 and a fuse F2; the fuse F1 and the fuse F2 are connected in parallel, and the fuse F2 branch is connected in series with a resistor R0; when the fuse F1 is blown, the fuse F2 branch is used to maintain the circuit protection function.

[0017] Preferably, when the input power supply is superimposed with 2V / 50Hz ripple interference, the circuit can normally perform power on / off operations.

[0018] Preferably, the switch circuit meets the following requirements: command response time < 64 ms, surge duration ≤ 5 ms, and current rising slope ≤ 10 A / μs.

[0019] The present invention further provides a method for controlling a satellite-borne long-life primary power switch circuit. The method applies the above-mentioned satellite-borne long-life primary power switch circuit and comprises the following steps:

[0020] Power-on steps: When the power-on command pulse is issued, the optocoupler is triggered to turn on, causing transistor Q1 to turn on for a set duration of 80ms. During this 80ms period, the MOS transistor is also turned on, powering up the voltage regulator and outputting a +5V voltage. When the 80ms duration of the power-on command pulse ends, transistor Q1 is still controlled to remain on to ensure continuous power-on operation of the product.

[0021] Shutdown steps: When the shutdown command pulse is issued, the optocoupler is turned on, the base potential of the transistor Q1 is pulled down, and then the MOS tube is controlled to be cut off, and finally the power supply is cut off.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. This invention uses all-semiconductor devices to achieve power switching and surge suppression functions; it completely solves the bottleneck of short life of relay mechanical contacts, meets the long life requirements of high-resolution / hyperspectral remote sensing satellites that frequently switch, and provides guarantee for long-term stable operation in orbit;

[0024] 2. The circuit design of the present invention has strong resistance to power ripple interference. When the input primary power supply is superimposed with 2V / 50Hz ripple, it can still stably realize the power on and off function. Combined with the optical coupler isolation command interface, it effectively blocks the conduction of onboard command noise, ensuring reliable operation in the strong electromagnetic interference environment in space.

[0025] 3. The present invention adopts a dual-fuse parallel protection circuit. When the main fuse blows, the backup branch can still provide protection. The redundant design greatly improves the reliability of overcurrent protection, avoids single-point failure and damage to equipment, and meets the high reliability requirements of aerospace.

[0026] 4. The present invention utilizes the conduction characteristics of MOSFET in combination with an RC gate control circuit to precisely control the current rising slope. It integrates surge suppression with the power switch function, effectively suppressing the startup surge current while achieving microsecond-level command response and protecting back-end devices.

[0027] 5. The single circuit of the present invention integrates core functions such as power switch, command isolation, surge suppression, power-off self-locking, and overcurrent protection; significantly simplifies the system architecture, reduces the number and volume of components, reduces power consumption and thermal control pressure, and meets the strict constraints of satellite resource utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Other features, objects and advantages of the present invention will become more apparent upon reading the detailed description of non-limiting embodiments with reference to the following drawings:

[0029] Figure 1 It is a system composition diagram of the present invention;

[0030] Figure 2 This is a circuit diagram of the on / off instruction interface circuit and the switch circuit of the present invention. DETAILED DESCRIPTION

[0031] The present invention will be described in detail below with reference to specific embodiments. The following examples will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those skilled in the art, several changes and improvements can be made without departing from the scope of the present invention. These all fall within the scope of protection of the present invention.

[0032] Example 1:

[0033] Reference Figure 1 and Figure 2 According to the present invention, a satellite-borne long-life primary power switch circuit includes: a surge suppression circuit 1, an on / off command interface circuit 2, and a switch circuit 3; the surge suppression circuit 1 is used for primary power surge suppression and primary power on / off control; the on / off command interface circuit 2 uses an optocoupler to achieve on-board command level conversion and electrical isolation, and outputs an on-state signal V open And off signal V close The switch circuit 3 receives the open signal V open And off signal V close , controls the on and off of the surge suppression circuit 1 and realizes power-on self-locking and power-off recovery; the surge suppression circuit 1 is used to realize the power switch function, and all semiconductor devices are used.

[0034] Surge suppression circuit 1 includes P-channel MOSFET Q1, parallel resistor R1 and capacitor C1, resistor R2 and resistor R3; resistor R1 and capacitor C1 are connected in parallel, and one end is connected to power supply VCC. in The other end is divided into two paths: one path is connected to the gate of P-channel MOSFET Q1 through resistor R2, and the other path is connected to the output end of switch circuit 3 through resistor R3; the source of P-channel MOSFET Q1 is connected to power supply VCC in , the drain serves as the primary power output terminal.

[0035] The on / off command interface circuit 2 includes: a voltage regulator U1, a resistor R7, an optocoupler U2, a resistor R4, a resistor R6, a resistor R5 and an optocoupler U3; the optocoupler U2 includes a transistor and a photodiode; the optocoupler U3 includes a transistor and a photodiode; the voltage regulator U1 and the resistor R7 are connected in series to generate a supply voltage for the collector of the transistor of the optocoupler U2; the on command is connected to the positive electrode of the photodiode of the optocoupler U2 through the resistor R4, the negative electrode of the photodiode of the optocoupler U2 is grounded, and the emitter of the transistor of the optocoupler U2 is pulled down through the resistor R6 to output an on signal V open The off command is connected to the positive electrode of the photodiode of the optocoupler U3 through the resistor R5, the negative electrode of the photodiode of the optocoupler U3 is grounded, and the collector of the transistor of the optocoupler U3 outputs the off signal V close .

[0036] The switch circuit 3 includes a transistor Q2, a diode D1, a diode D2, a resistor R8, a resistor R9, a resistor R10 and a voltage regulator U4; the open signal V open Connect the base of transistor Q2 through diode D1, and the off signal V closeThe base of transistor Q2 is connected to the diode D2, and the base of transistor Q2 is grounded through resistor R8; the collector of transistor Q2 is connected to resistor R3 of surge suppression circuit 1; the voltage regulator U4 is connected in series with resistor R10 to generate the working voltage VCC out , input the critical signal V through resistor R9 close node.

[0037] Resistor R1, capacitor C1 and resistor R2 form an RC circuit. The P-channel MOSFET Q1 controls the gate voltage rise rate of the P-channel MOSFET Q1 through the RC circuit, and uses the source-drain on-resistance to control the load current rise rate, thereby achieving surge suppression and power switching functions.

[0038] The switch circuit 3 triggers the P-channel MOSFET Q1 to turn on in response to the 80ms power-on command pulse, and maintains the on state after the pulse ends to achieve self-locking; in response to the shutdown command, it pulls down the gate voltage of the P-channel MOSFET Q1 to achieve power off.

[0039] A satellite-borne long-life primary power switch circuit also includes a redundant protection circuit, which includes a fuse F1 and a fuse F2; the fuse F2 is connected in series with a resistor R0 and then in parallel with the fuse F1; when the fuse F1 blows, the fuse F2 branch is used to maintain the circuit protection function.

[0040] When the input power supply is superimposed with 2V / 50Hz ripple interference, the circuit can perform normal power on and off operations. The switching circuit meets the following requirements: command response time <64ms, surge duration ≤5ms, and current rise slope ≤10A / μs.

[0041] The present invention further provides a method for controlling a satellite-borne long-life primary power switch circuit. The method applies the above-mentioned satellite-borne long-life primary power switch circuit and comprises the following steps:

[0042] Power-on steps: When the power-on command pulse is issued, the optocoupler is triggered to turn on, causing transistor Q1 to turn on for a set duration of 80ms. During this 80ms period, the MOS transistor is also turned on, powering up the voltage regulator and outputting a +5V voltage. When the 80ms duration of the power-on command pulse ends, transistor Q1 is still controlled to remain on to ensure continuous power-on operation of the product.

[0043] Shutdown steps: When the shutdown command pulse is issued, the optocoupler is turned on, the base potential of the transistor Q1 is pulled down, and then the MOS tube is controlled to be cut off, and finally the power supply is cut off.

[0044] Example 2:

[0045] The present invention relates to the technical field of primary power switch circuits, and in particular to the design of a satellite-borne long-life primary power switch circuit. The present invention relates to a satellite-borne primary power switch circuit, comprising an on / off command interface circuit 2, a surge suppression circuit 1, and a switch circuit 3. The on / off command interface circuit converts the onboard command level into a subsequent circuit control level and uses an optocoupler for signal isolation. The surge suppression circuit performs both primary power surge suppression and power switching functions. The switch circuit uses the command switch and surge suppression circuit outputs as circuit inputs, enabling the MOSFET to turn on upon power-up, self-lock after power-up, and control the MOSFET to disconnect upon shutdown.

[0046] A satellite-borne long-life primary power switch circuit 1, comprising: a surge suppression circuit 1 for primary power surge suppression, primary power electrical signal conduction and disconnection; an on / off command interface circuit 2 for inputting switch commands for electrical isolation, level conversion, and generating an output switch signal V open , V close For internal switching; switch circuit 3, used to convert the output power into internal working power, receiving module 2 output V open , V close Realize the switch control of module 1 and power failure recovery.

[0047] Surge suppression circuit 1, including: a primary power supply VCC in Input to the surge circuit module, the surge circuit module includes P-channel MOSFETQ1, resistors R1, R2, R3, C1, R1 and C1 are connected in parallel and then in series with R2 to connect to the G stage of Q1, R1 and C1 are connected in parallel and then in series with R3 and are controlled by the switch circuit 3.

[0048] The on / off command interface circuit 2 includes: using resistor R7 and voltage regulator U1 in series to generate a stable voltage to connect to the collector c of the optocoupler U2, and the emitter e of U2 is connected to the pull-down resistor R6 and outputs V open , the other end of R6 is connected to the signal ground; the on command is connected to the positive electrode of the U2 photodiode through a resistor in series, and the negative electrode of the U2 photodiode is connected to the command ground. The off command is connected to the positive electrode of the U3 photodiode through a resistor in series, and the negative electrode of the U3 photodiode is connected to the command ground. The collector of the U3 transistor is connected to V close , the emitter e is connected to the signal ground.

[0049] Switching circuit 3 includes: using resistor R10 and voltage regulator U4 in series to generate a stable voltage which is then connected to V through R9. close , V close After being connected in series with diode D2, it is input to the base of transistor Q2, V open After being connected in series with the diode D1, the base b of the input transistor Q2 is connected to the signal ground through the resistor R8, and the collector C of Q2 is connected to the resistor R3 of the module 1.

[0050] A satellite-borne long-life primary power switch circuit includes: a switch instruction of +28V, a high level, a level width of 80ms, an instruction response time of less than 64ms, a surge duration of no more than 5ms, and a rising slope of less than 10A / S.

[0051] The present invention proposes an innovative switching circuit design scheme, including the use of optocouplers for command control signal conversion and command power isolation, using the original surge circuit as a primary power switch, and the surge circuit output to lock the control circuit, realizing power-on self-locking, command power-off function, and power-off recovery to match the operation of satellite-borne products. The switch life meets the requirements of long-life working mode and ensures stable operation in complex space environments.

[0052] A satellite-borne long-life primary power switch circuit includes an on / off command interface circuit, a surge suppression circuit, and a switch circuit. The surge suppression circuit is used to suppress primary power surges and turn primary power electrical signals on and off; the on / off command interface circuit is used to electrically isolate input switch commands and generate output switch signals V by level conversion. open , V close Used for internal switching; the switching circuit is used to convert the output power into the internal working power supply, and receives the V output of the on / off instruction circuit open , V close The onboard long-life primary power switch circuit integrates protection and surge current suppression functions.

[0053] The switching method of the satellite-borne long-life primary power switching circuit according to the present invention includes the following steps:

[0054] Power-on control process: When the power-on command pulse is issued, the optocoupler is triggered to conduct, causing transistor Q1 to conduct for a set duration of 80ms. During this 80ms period, the MOS transistor also conducts, powering up the voltage regulator and outputting +5V. Even after the 80ms duration of the power-on command pulse expires, transistor Q1 remains on, ensuring continuous power-on operation.

[0055] Shutdown control process: When the shutdown command pulse is issued, the optocoupler is turned on, causing the base potential of the transistor Q1 to be pulled down, thereby controlling the MOS tube to be cut off, and finally cutting off the primary power supply.

[0056] Protection Circuit Design: The protection circuit utilizes fuses. To improve fuse reliability, two fuses are connected in parallel, with a resistor connected in series with one of them. This design ensures that even after the fuse not connected in series with the resistor blows, the fuse connected in series with the resistor branch can continue to provide protection. Although this design increases the resistance of the power supply circuit, resulting in a corresponding increase in voltage drop, it still enables the equipment to operate normally. This dual-fuse design improves circuit redundancy and reliability, ensuring effective protection even if a single fuse fails. Furthermore, by properly selecting the fuse current rating and resistor value, the impact on circuit performance can be minimized while ensuring effective protection.

[0057] Inrush current suppression methods: Inrush current is generated at the moment the power is turned on or off due to the charging and discharging characteristics of capacitors, which can adversely affect system stability and components. This invention uses a MOSFET-based inrush current suppression circuit and an active inrush current suppression method. This circuit controls the rise rate of the MOSFET gate voltage through an RC circuit and controls the rise rate of the load current through its source-drain on-resistance, thereby achieving surge suppression.

[0058] This invention uses all-semiconductor devices, employing optocouplers for command level conversion and electrical isolation. Conventional satellite-borne power switching circuits often use relays, whose lifespan at rated operating current is insufficient to meet the longevity requirement of more than 100,000 switching cycles. This invention utilizes MOSFETs for both surge suppression and power switching, easily overcoming relay life limitations and achieving a switching lifespan exceeding 100,000 cycles. This provides a solid foundation for the long-term, stable operation of satellite-borne payloads on-orbit.

[0059] Through reasonable design and layout, the present invention enables the circuit to still operate stably and realize the power on and off function normally when a 2V, 50Hz ripple interference is connected in series with the primary power supply end, demonstrating an anti-interference capability far superior to that of traditional circuits, ensuring that spaceborne equipment is not affected by interference in the complex electromagnetic environment of space and operates stably and reliably.

[0060] The present invention utilizes two fuses in parallel, one of which is connected in series with a resistor, in its protection circuit design. This dual-fuse design effectively improves fuse reliability, enhances circuit redundancy and fault tolerance, and mitigates the risk of equipment damage caused by protection circuit failure.

[0061] The present invention adopts a MOSFET-based surge current suppression circuit, which accurately controls the MOS tube gate voltage rise rate through an RC circuit, and uses the source-drain on-resistance to control the load current rise rate, thereby controlling the surge current and effectively protecting circuit components from damage caused by surge current. While providing a fast response, the present invention better takes into account the surge suppression performance, ensuring system stability and reliability.

[0062] This invention not only implements basic power switch functions but also cleverly integrates multiple features, including overcurrent protection, undervoltage protection, inrush current suppression, power-on self-locking, and power-off recovery, creating a highly integrated primary power switch solution. This multifunctional integrated design simplifies the circuit structure, reduces the number and size of components, and improves the integrity and coordination of the system.

[0063] The satellite-borne long-life primary power switch circuit of the present invention is mainly composed of a surge suppression circuit, an on / off instruction interface circuit and a switch circuit.

[0064] In the surge suppression circuit, the primary power supply VCC in Input to this module. This module consists of a P-channel MOSFET Q1, resistors R1, R2, R3, and capacitor C1. R1 and C1 are connected in parallel, then in series with R2, to Q1's G stage. Furthermore, R1 and C1 are connected in parallel, then in series with R3. This combination is controlled by a switching circuit. This design effectively suppresses primary power surges and enables the primary power supply's electrical signal to be turned on and off.

[0065] The on / off command interface circuit is mainly used to realize the electrical isolation and level conversion of the input switch command and generate the output switch signal V open and V close Used for internal switch operation. The module uses resistor R7 and voltage regulator U1 in series to generate a stable voltage, which is connected to the collector of the optocoupler U2. The emitter of U2 is connected to the pull-down resistor R6 and outputs V open , and the other end of R6 is connected to the signal end. For the processing of the on and off instructions, they are connected to the positive electrode of the U2 photodiode through resistors in series, and the negative electrode of the U2 photodiode is connected to the instruction ground. Among them, the collector of the U2 transistor is connected to V close , the emitter is connected to the signal ground.

[0066] The switch circuit is responsible for converting the output power into internal working power and receiving the V output from the on / off command interface circuit. open and V close The module uses resistor R10 and voltage regulator U4 in series to generate a stable voltage, which is then connected to V close . V close After being connected in series with diode D2, it is input to the base of transistor Q2, and V open After being connected in series with diode D1, it is also input to the base of transistor Q2. The base of Q2 is connected to the signal ground through resistor R8, and its collector is connected to resistor R3 in the surge suppression circuit.

[0067] In specific implementations, when a power-on command pulse is issued, the optocoupler is triggered to conduct, causing transistor Q1 to conduct for a set duration of 80ms. During this 80ms period, the MOS transistor is also turned on, powering up the voltage regulator and outputting a +5V voltage. After the 80ms duration of the power-on command pulse expires, transistor Q1 is still controlled to remain on, ensuring continuous power operation. When a power-off command pulse is issued, the optocoupler is turned on, lowering the base potential of transistor Q1, thereby controlling the MOS transistor to turn off and ultimately shutting off the primary power supply.

[0068] To improve circuit reliability and redundancy, the protection circuit utilizes fuses. Two fuses are connected in parallel, with a resistor connected in series with one of them. This design ensures that even if the fuse not connected in series with the resistor blows, the fuse connected in series with the resistor branch can continue to provide protection. This effectively enhances circuit redundancy and reliability, ensuring effective protection even if a single fuse fails.

[0069] In practical applications, the present invention's onboard long-life primary power switch circuit can be widely used in various satellite payloads, particularly those requiring high switch life and reliability. Its integrated features, including command electrical isolation, overcurrent protection, and inrush current suppression, ensure stable circuit operation in complex space environments, providing a strong guarantee for the long-term, reliable operation of onboard equipment.

[0070] Those skilled in the art may understand this embodiment as a more specific description of Embodiment 1.

[0071] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. The embodiments of this application and the features in the embodiments may be combined with each other in any manner unless there is a conflict.

Claims

1. A satellite-borne long-life primary power switch circuit, characterized in that: include: A surge suppression circuit (1), an on / off command interface circuit (2) and a switch circuit (3); the surge suppression circuit (1) is used for primary power surge suppression and primary power on / off control; the on / off command interface circuit (2) realizes on-board command level conversion and electrical isolation through an optical coupler, and outputs an on signal V open And off signal V close The switch circuit (3) receives an open signal V open And off signal V close , controlling the on and off of the surge suppression circuit (1) and realizing power-on self-locking and power-off recovery; the surge suppression circuit (1) is used to realize the power switch function, and all semiconductor devices are used.

2. The satellite-borne long-life primary power switch circuit according to claim 1, characterized in that: The surge suppression circuit (1) comprises a P-channel MOSFET Q1, a resistor R1 and a capacitor C1 connected in parallel, a resistor R2 and a resistor R3; The resistor R1 and the capacitor C1 are connected in parallel and one end is connected to the power supply VCC in The other end is divided into two paths: one path is connected to the gate of the P-channel MOSFET Q1 through the resistor R2, and the other path is connected to the output end of the switch circuit (3) through the resistor R3; the source of the P-channel MOSFET Q1 is connected to the power supply VCC in , the drain serves as the primary power output terminal.

3. The satellite-borne long-life primary power switch circuit according to claim 1, characterized in that: The on / off command interface circuit (2) comprises: a voltage regulator tube U1, a resistor R7, an optical coupler U2, a resistor R4, a resistor R6, a resistor R5 and an optical coupler U3; The optocoupler U2 includes a transistor and a photodiode; the optocoupler U3 includes a transistor and a photodiode; the voltage regulator U1 is connected in series with the resistor R7 to generate the supply voltage for the collector of the transistor of the optocoupler U2; the open command is connected to the positive electrode of the photodiode of the optocoupler U2 through the resistor R4, the negative electrode of the photodiode of the optocoupler U2 is grounded, and the emitter of the transistor of the optocoupler U2 is pulled down by the resistor R6 to output the open signal V open The off command is connected to the positive electrode of the photodiode of the optocoupler U3 through the resistor R5, the negative electrode of the photodiode of the optocoupler U3 is grounded, and the collector of the transistor of the optocoupler U3 outputs the off signal V close .

4. The satellite-borne long-life primary power switch circuit according to claim 1, characterized in that: The switch circuit (3) includes a transistor Q2, a diode D1, a diode D2, a resistor R8, a resistor R9, a resistor R10 and a voltage regulator U4; The open signal V open Connect the base of transistor Q2 through diode D1, and the off signal V close The base of the transistor Q2 is connected to the diode D2, and the base of the transistor Q2 is grounded via the resistor R8; the collector of the transistor Q2 is connected to the resistor R3 of the surge suppression circuit (1); the voltage regulator U4 and the resistor R10 are connected in series to generate the working voltage VCC out , input the critical signal V through resistor R9 close node.

5. The satellite-borne long-life primary power switch circuit according to claim 2, characterized in that: The resistor R1, capacitor C1 and resistor R2 form an RC circuit. The P-channel MOSFET Q1 controls the gate voltage rise rate of the P-channel MOSFET Q1 through the RC circuit, and controls the load current rise rate using the source-drain on-resistance to achieve surge suppression and power switching functions.

6. The satellite-borne long-life primary power switch circuit according to claim 1, characterized in that: The switch circuit (3) triggers the P-channel MOSFET Q1 to turn on in response to an 80ms power-on command pulse, and maintains the on state after the pulse ends to achieve self-locking; and pulls down the gate voltage of the P-channel MOSFET Q1 in response to a power-off command to achieve power off.

7. The satellite-borne long-life primary power switch circuit according to claim 1, characterized in that: The circuit also includes a redundant protection circuit, which includes a fuse F1 and a fuse F2; the fuse F1 and the fuse F2 are connected in parallel, and the fuse F2 branch is connected in series with a resistor R0; when the fuse F1 is blown, the fuse F2 branch is used to maintain the circuit protection function.

8. The satellite-borne long-life primary power switch circuit according to claim 1, characterized in that: When the input power supply is superimposed with 2V / 50Hz ripple interference, the circuit can perform power on and off operations normally.

9. The satellite-borne long-life primary power switch circuit according to claim 1, characterized in that: The switch circuit meets the following requirements: command response time < 64 ms, surge duration ≤ 5 ms, and current rising slope ≤ 10 A / μs.

10. A control method for a satellite-borne long-life primary power switch circuit, characterized in that: The method uses the satellite-borne long-life primary power switch circuit according to any one of claims 1 to 9, and the method comprises the following steps: Power-on steps: When the power-on command pulse is issued, the optocoupler is triggered to turn on, causing transistor Q1 to turn on for a set duration of 80ms. During this 80ms period, the MOS transistor is also turned on, powering up the voltage regulator and outputting a +5V voltage. When the 80ms duration of the power-on command pulse ends, transistor Q1 is still controlled to remain on to ensure continuous power-on operation of the product. Shutdown steps: When the shutdown command pulse is issued, the optocoupler is turned on, the base potential of the transistor Q1 is pulled down, and then the MOS tube is controlled to be cut off, and finally the power supply is cut off.

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