Low energy consumption aerospace electronic switch

Abstract

This utility model relates to the field of electronic switch technology, specifically a low-power aerospace-grade electronic switch. The displacement sensor and fault detection chip are connected by electrical signals. The main switch circuit module and the backup switch circuit module are in parallel. The fault detection chip and the MEMS switch unit are connected by electrical signals. The K-type thermocouple and the shape memory alloy spring are connected by electrical signals. Through the double-layer shielding of "tungsten metal film + nano-ceramic", the false alarm rate caused by space radiation is reduced by 97.5%, meeting the reliability requirements of a 10-year service life of low Earth orbit (LEO) satellites. It has a built-in temperature adaptive compensation system, and the contact resistance fluctuation is ≤±1% in the range of -196℃ (liquid nitrogen environment) to +200℃ (high temperature oven). No external temperature sensor calibration is required, making it suitable for extreme temperature difference scenarios such as engine compartments.

Description

Technical Field

[0001] This utility model relates to the field of electronic switch technology, specifically a low-power aerospace-grade electronic switch. Background Technology

[0002] In the aerospace field, electronic switches, as core components of control circuits, must operate stably in extreme environments such as high temperatures (-196℃ to +200℃), strong radiation (≥100 klad(Si)), and severe vibration (50g acceleration). However, existing aerospace-grade electronic switches have the following shortcomings:

[0003] High radiation sensitivity: Traditional semiconductor materials are prone to ionization noise under space radiation, which leads to an increased rate of switch malfunction (according to statistics, the annual failure rate of satellite switches reaches 8%).

[0004] Energy consumption and heat generation issues: The high on-resistance of the metal contacts (>0mΩ for redundant control modules) leads to significant energy loss during high-frequency switching, and local temperature rise can reach over 50℃, affecting system thermal management. Utility Model Content

[0005] (a) Technical problems to be solved

[0006] To address the shortcomings of existing technologies, this invention provides a low-energy-consumption aerospace-grade electronic switch.

[0007] (II) Technical Solution

[0008] To achieve the above objectives, the present invention provides the following technical solution: a low-power aerospace-grade electronic switch, comprising a substrate, wherein a MEMS switching unit, a redundant control module and a temperature compensation module are integrated on the substrate;

[0009] The MEMS switching unit includes a movable contact, a fixed contact, a shape memory alloy spring, a displacement sensor, and a driving electrode; the redundant control module includes a main switching circuit module, a backup switching circuit module, and a fault detection chip; and the temperature compensation module includes a K-type thermocouple.

[0010] The displacement sensor and the fault detection chip are connected by an electrical signal. The main switch circuit module and the backup switch circuit module are connected in parallel. The fault detection chip and the MEMS switch unit are connected by an electrical signal. The K-type thermocouple and the shape memory alloy spring are connected by an electrical signal.

[0011] To quickly dissipate the heat generated at the contacts, the improvements of this invention include: the substrate is made of a pure alumina ceramic substrate, and a graphene thermal conductive layer is sputtered on its bottom surface; the substrate is made of a 99.6% pure alumina ceramic substrate, and a 5μm thick graphene thermal conductive layer is sputtered on its bottom surface.

[0012] Furthermore, an improvement of this invention is that the MEMS switching unit is fixed to the center of the substrate using flip-chip bonding technology.

[0013] Furthermore, the improvement of this utility model is that the movable contact is made of copper-beryllium alloy substrate, with a 10μm gold-germanium alloy plating on the surface, and the contact resistance is ≤30mΩ.

[0014] To ensure the anti-interference effect of the MEMS switching unit, the present invention includes an improvement in that the MEMS switching unit is provided with a radiation shielding layer, which comprises an inner tungsten metal film and an outer nano-ceramic layer.

[0015] (III) Beneficial Effects

[0016] Compared with the prior art, this utility model provides a low-power aerospace-grade electronic switch, which has the following beneficial effects:

[0017] By using a double-layer shield of "tungsten metal film + nano-ceramics", the malfunction rate caused by space radiation is reduced by 97.5%, meeting the reliability requirements of a 10-year service life for low Earth orbit (LEO) satellites.

[0018] With a built-in temperature adaptive compensation system, the contact resistance fluctuation is ≤±1% in the range of -196℃ (liquid nitrogen environment) to +200℃ (high temperature oven), requiring no external temperature sensor calibration, and is suitable for extreme temperature difference scenarios such as engine compartment.

[0019] MMEMS micro-contacts combined with a gold-germanium alloy coating reduce the on-resistance by 60% (≤50mΩ) compared to traditional switches, and the power loss at 10A current is only 5W (compared to 12.5W for traditional switches), effectively reducing the energy consumption of spacecraft batteries. Attached Figure Description

[0020] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0021] Figure 2 This is a system diagram of the MEMS switching unit in this invention;

[0022] Figure 3 This is a system diagram of the redundant control module in this utility model;

[0023] Figure 4 This is a system diagram of the temperature compensation module in this utility model;

[0024] In the diagram: 1. Substrate; 2. MEMS switch unit; 3. Silicon-based frame; 4. Movable contact; 5. Fixed contact; 6. Memory alloy spring; 7. Displacement sensor; 8. Drive electrode; 9. Fault detection chip; 10. Redundant control module; 11. Main switch circuit module; 12. Backup switch circuit module; 13. Temperature compensation module; 14. K-type thermocouple. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] Please see Figure 1-4 The present invention provides a low-energy aerospace-grade electronic switch, comprising a substrate 1, wherein a MEMS switching unit 2, a redundant control module 10, and a temperature compensation module 13 are integrated on the substrate 1.

[0027] The MEMS switch unit 2 includes a movable contact 4, a fixed contact 5, a memory alloy spring 6, a displacement sensor 7, and a driving electrode 8. The redundant control module 10 includes a main switch circuit module 11, a backup switch circuit module 12, and a fault detection chip 9. The temperature compensation module 13 includes a K-type thermocouple 14.

[0028] The displacement sensor 7 is connected to the fault detection chip 9 via electrical signals. The main switch circuit module 11 and the backup switch circuit module 12 are connected in parallel. The fault detection chip 9 is connected to the MEMS switch unit 2 via electrical signals. The K-type thermocouple 14 is connected to the shape memory alloy spring 6 via electrical signals.

[0029] In this embodiment, the substrate 1 is a pure alumina ceramic substrate, and a graphene thermal conductive layer is sputtered on its bottom surface. The substrate 1 is a 99.6% pure alumina ceramic substrate, and a 5μm thick graphene thermal conductive layer is sputtered on its bottom surface.

[0030] In this embodiment, the MEMS switch unit 2 is fixed to the center of the substrate 1 by flip-chip bonding technology.

[0031] In this embodiment, the movable contact 4 is made of copper-beryllium alloy substrate, with a 10μm gold-germanium alloy plating on the surface, and the contact resistance is ≤30mΩ.

[0032] Substrate 1: It adopts a 99.6% high-purity alumina ceramic substrate, and a 5μm thick graphene thermal conductive layer is formed on the bottom surface by chemical vapor deposition (CVD). The thermal conductivity reaches 500W / (m·K), which is 40% higher than that of the traditional alumina substrate 1. It can control the contact temperature rise within 10℃ within 10ms.

[0033] MMEMS switch unit 2: Fabricated using microfabrication processes such as photolithography and deep etching, the silicon-based frame 3 is 0.5 mm thick and integrates movable contact 4 and fixed contact 5. Movable contact 4 uses a copper-beryllium alloy substrate with a 10 μm gold-germanium alloy (85% gold content) electroplated on the surface. Atomic force microscopy shows a surface roughness ≤5 nm and a stable contact resistance of 30-40 mΩ. The contact is connected to the silicon-based frame 3 via a 0.2 mm diameter shape memory alloy spring 6. The spring's phase transition temperature is set to 80℃ to ensure a contact pressure of 20 mN ± 2 mN even at high temperatures.

[0034] In this embodiment, the MEMS switch unit 2 is provided with a radiation shielding layer, which includes an inner tungsten metal film and an outer nano-ceramic layer.

[0035] Radiation shielding layer: It adopts a double-layer composite structure. The inner layer is a 75μm tungsten film deposited by magnetron sputtering with a tungsten content of ≥99.95%, which can shield more than 80% of gamma rays with energy ≥1MeV. The outer layer is a 250μm Al2O3-ZrO2 nano-ceramic layer sprayed by plasma spraying with a ceramic grain size ≤50nm, forming a dense protective layer that effectively blocks the penetration of charged particles in space.

[0036] The redundant control module 10 is integrated on the substrate 1. The main / backup switching circuit adopts a parallel design, with each circuit independently controlling a set of MMEMS switching units 2. When the circuit is on, only the main circuit works, while the backup circuit is in hot standby mode (leakage current <1μA). The fault detection chip 9 has a built-in high-precision ADC module that collects the signals from the displacement sensor 7 (resolution 0.1μm) and the contact voltage signals (accuracy ±0.1%) in real time. When the contact resistance of the main switching unit is detected to be >50mΩ or the contact displacement deviation is detected to be >10%, switching is triggered by a solid-state relay (SSR). The switching signal transmission delay is ≤3μs, and the overall response time is <8μs.

[0037] Temperature compensation system: A miniature K-type thermocouple 14 is embedded in the corner of the substrate 1, with a temperature measurement accuracy of ±0.5℃. In conjunction with the MCU, the thermal expansion of the contact is calculated in real time, and the heating power of the shape memory alloy spring 6 is adjusted by the PWM signal to achieve dynamic compensation of the contact gap (compensation accuracy ±0.5μm).

[0038] Radiation resistance:

[0039] In experiments conducted under a cobalt-60 radiation source, when the cumulative dose reached 100 krad (Si), the leakage current of the conventional switch increased from 5 μA to 200 μA, while the leakage current of this switch only increased to 15 μA by absorbing high-energy particles with a tungsten metal film and suppressing ionization noise with a nano-ceramic layer, and the false trip rate decreased from 12% to 0.3%.

[0040] Low power consumption characteristics:

[0041] Employing MMEMS micro-contacts (8μm pitch) and a nitrogen protective gas layer (100kPa pressure), the single-switch loss is reduced to 8μJ (compared to 50μJ / switch for traditional electromagnetic relays). Combined with a graphene thermal conductive layer, the surface temperature rise of substrate 1 is <15℃ during continuous operation (100 times / minute), eliminating the need for additional heat dissipation devices.

[0042] Enhanced radiation resistance: Through a double-layer shielding system of "tungsten metal film + nano-ceramics", the malfunction rate caused by space radiation is reduced by 97.5%, meeting the reliability requirements of low Earth orbit (LEO) satellites for a 10-year service life (annual failure rate <0.5%).

[0043] Stable operation over a wide temperature range: The built-in temperature adaptive compensation system ensures that the contact resistance fluctuation is ≤±1% within the range of -196℃ (liquid nitrogen environment) to +200℃ (high temperature oven). No external temperature sensor calibration is required, making it suitable for extreme temperature difference scenarios such as engine compartments.

[0044] Energy efficiency ratio significantly improved:

[0045] Low conduction loss: MMEMS micro-contacts combined with gold-germanium alloy coating reduce conduction resistance by 60% (≤50mΩ) compared to traditional switches, and power loss is only 5W at 10A current (compared to 12.5W for traditional switches), effectively reducing spacecraft battery energy consumption.

[0046] Low driving energy: The shape memory alloy spring 6 has a driving voltage of only 5V, and the energy required for a single switch is <10μJ, which is 90% lower than that of electromagnetic switches (driving energy >100μJ), making it suitable for solar-powered drones, satellites and other equipment.

[0047] Overall enhanced reliability:

[0048] Redundant fault-tolerant design: The dual-path parallel switching system reduces the probability of single-point failure from 5% to below 0.1%, with a switching time of <10μs, ensuring the continuous conduction of critical circuits such as the missile control system and avoiding mission interruption due to switch failure.

[0049] Long lifespan characteristics: The vibration buffer structure and nitrogen protective gas layer reduce contact wear. After 500,000 life tests, the contact loss is <5μm, which far exceeds the 50,000 lifespan requirement specified in GJB128A, reducing the on-orbit maintenance cost of aerospace equipment.

[0050] Integration and lightweight design:

[0051] High-density integration: A single switch module integrates main / backup circuits, detection chips and compensation systems, reducing the size by 60% compared to traditional redundancy solutions and weighing only 1.2g, making it suitable for load-sensitive unmanned aerial vehicles.

[0052] High environmental compatibility: Passing reliability tests such as salt spray and mold (refer to GJB150 standard), the surface shows no corrosion and no decrease in insulation, and can work stably in complex environments such as marine environments and tropical climates.

[0053] In the description herein, it should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0054] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention.

Claims

1. A low-power aerospace-grade electronic switch, comprising a substrate (1), characterized in that: The substrate (1) integrates a MEMS switching unit (2), a redundant control module (10), and a temperature compensation module (13). The MEMS switch unit (2) includes a movable contact (4), a fixed contact (5), a memory alloy spring (6), a displacement sensor (7), and a driving electrode (8). The redundant control module (10) includes a main switch circuit module (11), a backup switch circuit module (12), and a fault detection chip (9). The temperature compensation module (13) includes a K-type thermocouple (14). The displacement sensor (7) is connected to the fault detection chip (9) via electrical signals. The main switch circuit module (11) and the backup switch circuit module (12) are connected in parallel. The fault detection chip (9) is connected to the MEMS switch unit (2) via electrical signals. The K-type thermocouple (14) is connected to the memory alloy spring (6) via electrical signals.

2. The low-power aerospace-grade electronic switch according to claim 1, characterized in that: The MEMS switch unit (2) is fixed to the center of the substrate (1) by flip-chip bonding technology.

3. The low-power aerospace-grade electronic switch according to claim 2, characterized in that: The movable contact (4) is made of copper-beryllium alloy substrate, with a 10μm gold-germanium alloy plating on the surface, and the contact resistance is ≤30mΩ.

4. A low-power aerospace-grade electronic switch according to claim 3, characterized in that: The MEMS switch unit (2) is provided with a radiation shielding layer, which includes an inner tungsten metal film and an outer nano-ceramic layer.

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