Aero-engine dynamic stress telemetry signal transmission system

Abstract

The invention discloses an aero-engine dynamic stress telemetry signal transmission system which comprises a signal acquisition module, a signal receiving module and a power supply module which are independently installed in an engine, signal transmission is conducted between the signal acquisition module and the signal receiving module through an antenna, and the signal acquisition module comprises an amplifier and a DC / AC conversion module. The signal receiving module comprises a signal receiver and an upper computer; a non-contact signal transmission and power supply design is adopted, a traditional slip ring and wired connection are thoroughly abandoned, the problem of abrasion at a high rotating speed is solved, and the telemetering and measuring device can be modularized, miniaturized and installed in an engine to achieve the purpose of measuring the dynamic stress of a gas compressor rotor and a turbine rotor.

Description

Technical Field

[0001] This invention relates to a remote signal transmission system for dynamic stress of an aero-engine. Background Technology

[0002] The aero-engine is the heart of an aircraft, and its performance directly affects the aircraft's performance and combat capability. During engine operation, measuring the dynamic stress parameters of the rotor is a crucial part of engine testing and a key technical indicator for assessing the engine's structural strength and operational reliability. However, obtaining accurate dynamic stress parameters for high-speed rotating components under harsh operating conditions such as confined spaces, high speeds, and high temperatures has always been a challenge.

[0003] Currently, dynamic stress measurement of rotor components typically employs wireless telemetry technology. This technology offers advantages such as flexible installation, multiple channels, and wide applicability. However, when applied to dynamic stress measurement of aero-engines, the telemetry equipment, due to its large size, cannot be installed inside the engine and must be placed in locations with ample space, such as the fairing or shaft end. Therefore, in overall engine measurement, dynamic stress measurement is usually limited to fan rotor components, and cannot be performed on compressor and turbine rotor components at the engine's rear end. Summary of the Invention

[0004] The purpose of this invention is to address the problem that existing telemetry systems cannot measure and obtain dynamic stress data of compressor and turbine rotors. This invention designs a modular and miniaturized dynamic stress measurement device. Based on the composition of the telemetry device, it is decomposed into modules such as a telemetry transmitting antenna, a telemetry receiving antenna, a power supply coil, an amplifier module, an AC / DC conversion module, and cables. According to the internal structure of the engine, a corresponding mounting structure is designed and installed in the space between the zero and first stage rotors of the compressor. In this way, the problem of the telemetry measurement device being too large and unable to be installed due to insufficient internal engine space is solved.

[0005] The technical solution of this invention: A telemetry signal transmission system for dynamic stress of an aero-engine includes a signal acquisition module, a signal receiving module, and a power supply module, which are installed independently in the engine. The signal acquisition module and the signal receiving module transmit signals through an antenna. The signal acquisition module includes an amplifier and a DC / AC conversion module. The signal receiving module includes a signal receiver and a host computer. The amplifier receives and amplifies the dynamic stress signals of the engine compressor and turbine rotor, encodes and modulates them into radio frequency signals through a DC / AC conversion module, and then transmits them to the signal receiver through an antenna. The power supply module adopts a loosely coupled inductive power supply method, which transmits the power from the signal receiving module to the signal acquisition module through an inductive power supply exciter.

[0006] The antenna includes a transmitting antenna and a receiving antenna. The transmitting antenna is connected to the DC / AC module through a parallel capacitor and an inductor, and the receiving antenna is connected to a signal receiver.

[0007] The transmitting antenna is fixed on the outer wall of the engine's sprocket ring, and the receiving antenna is mounted on the engine stator via a receiving mounting bracket and is opposite to the transmitting antenna.

[0008] The receiving mounting base is fixed to the engine stator by bolts, and its outer wall is in contact with the engine stator. Both its inner and outer ends are provided with support rings that are coaxial with the engine shaft. The receiving antenna is fixed to the inner support ring by bolts.

[0009] The transmitting antenna is less than 1 / 4 wavelength in length, and the receiving antenna is a loop antenna.

[0010] The power supply module includes a primary coil and a secondary coil. The primary coil is connected to the output terminal of the inductive power supply exciter, and the input terminal of the inductive power supply exciter draws power from the signal receiver. The secondary coil is connected to the amplifier and the DC / AC conversion module for power supply.

[0011] A capacitor is connected in parallel between the two poles of the primary coil and the secondary coil.

[0012] The primary and secondary coils are wound with copper wire with a diameter of 0.3mm.

[0013] The primary coil is mounted on the outer ring of the receiving mounting base. The secondary coil is mounted between the engine zero-stage plate and the stator via the secondary coil mounting base. The amplifier and DC / AC conversion module are mounted between the engine zero-stage plate and the first-stage plate via the module mounting base. The secondary coil mounting base is coaxially mounted on the zero-stage plate, and its edge is provided with a secondary support ring coaxial with the primary coil. The secondary coil is fixed on the secondary support ring.

[0014] Multiple module mounting bases are evenly arranged around the circumference of the zero-level disk according to the number of signal acquisition modules. Each module mounting base has two through holes that match the shapes of the amplifier and the DC / AC conversion module, respectively.

[0015] The beneficial effects of this invention are: by adopting a non-contact signal transmission and power supply design, the traditional slip ring and wired connection are completely eliminated, the wear problem at high speed is solved, and the telemetry measurement device can be modularized and miniaturized and installed inside the engine to achieve the purpose of measuring the dynamic stress of the compressor rotor and turbine rotor. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the telemetry signal transmission system.

[0017] Figure 2 This is a schematic diagram of the installation structure of each module inside the engine.

[0018] Figure 3 This is a schematic diagram of the power supply coil resonance compensation circuit.

[0019] Figure 4 This is a schematic diagram of the resonant circuit structure of the transmitting antenna.

[0020] Figure 5 This is a schematic diagram of the transmitting antenna structure.

[0021] Figure 6 This is a schematic diagram of the high-frequency circuit structure of the receiving antenna.

[0022] Figure 7 This is a schematic diagram of the receiving antenna structure.

[0023] Figure 8 This is a schematic diagram of the stress distribution of the module mounting base.

[0024] Reference numerals: 1-Secondary coil; 2-Transmitting antenna; 3-Grate ring; 4-Amplifier module; 5-AC / DC conversion module; 6-Primary coil; 7-Wire; 8-Module mounting base; 9-Zero-stage coil; 10-Secondary coil mounting base; 11-Receiver antenna mounting base; 12-Receiver antenna; 13-Primary coil. Detailed Implementation

[0025] Example: This example is based on the Datatel telemetry system design, and the power supply module and signal transmission module are designed according to the actual space structure of the engine.

[0026] 1. Module mounting bracket Since each amplifier module needs to be used with an AC / DC conversion module, the dimensions of Datatel's amplifier modules and AC / DC conversion modules, such as... Figure 2 As shown, the module mounting base adopts a segmented design, consisting of two sections, each holding one amplifier module and one AC / DC conversion module. The module mounting base is placed between the zero-stage and first-stage panels and is bolted to the zero-stage panel; the material selected is TC4. Figure 8 As shown, the maximum equivalent stress is 844 MPa, which is greater than the yield strength of TC4 material, indicating that the structure has entered the plastic stage. The plastic deformation test results show that the maximum plastic strain is 5.4%, which is less than the material's fracture strain (approximately 12%). The strength of the module mounting base meets the test requirements.

[0027] 3. Power supply coil (primary side) and receiving antenna mounting structure The power supply coil (primary side) and receiving antenna mounting base are designed according to the spatial structure. See the structural diagram below. Figure 2As shown. This component is a stator, fixed by bolts. The first-order vibration mode of the power supply coil (primary side) and the receiving antenna mounting base was calculated: under the installation conditions, its first-order frequency is 3231.9Hz. The first-order frequency is much higher than the rotor speed frequency, so resonance will not occur, which meets the test requirements.

[0028] 4. Power supply coil design The power supply coil adopts a loosely coupled inductive power supply method. According to the working requirements of the Datatel telemetry system, the working frequency is 120kHz±10%, the primary voltage is 60Vpp, and the secondary voltage is (20-24)Vpp.

[0029] Core selection: Manganese zinc ferrite PC40 material is selected, with a U-shaped core structure and model UF9.8. This core has the characteristics of small impedance deviation, large output current, high inductance, and suppression of high-order harmonics.

[0030] Coil selection: Based on the voltage operating frequency (120±10%) kHz, the radial depth of the high-frequency skin current penetrating along the surface of the conductor to the center is determined. Calculation formula: ........................(1) In the formula: — angular frequency, ; —Permeability, for copper wire H / m; —Conductivity, for copper wires .

[0031] When a current with a frequency of 120kHz passes through a copper wire, the radial depth can be calculated to be 0.19mm using the formula. Based on the principle that the wire diameter is less than twice the penetration depth, a copper wire with a diameter of 0.3mm is selected for winding.

[0032] Compensation Circuit: Because the primary and secondary coils are separate, the coupling is loose, resulting in significant leakage flux and a small magnetizing inductance, leading to a very low coupling coefficient. To reduce power loss and improve power transmission efficiency, resonant compensation is needed on both sides of the transformer. The simplest method is to connect a capacitor in parallel between the primary and secondary coils to achieve resonant compensation. See the circuit design section below. Figure 3 .

[0033] 5. Transmitting Antenna Design The transmitting antenna is installed on the toothed ring according to the structural dimensions. Due to the requirements of the metallic environment and limited installation space, and based on the carrier frequencies of the selected amplifier modules being 2060MHz and 2090MHz, the calculated wavelengths are 145.6mm (2060MHz) and 143.5mm (2090MHz). To ensure signal transmission stability, the antenna length should be less than 1 / 4 wavelength; therefore, the antenna length is 30mm, with a center-fed method. Since the antenna is capacitive, an inductor is needed for balance, thus causing the antenna to resonate. The compensation circuit is shown below. Figure 4 See the model diagram. Figure 5 .

[0034] 6. Receiving Antenna Design A receiving antenna is mounted on the power supply coil (primary side) and the receiving antenna mounting base. When the test shaft rotates at high speed, the transmitting antenna and the rotating shaft move in a circular motion simultaneously, making the wireless communication channel extremely complex. The signal received by the receiving antenna reaches the receiving antenna through various paths, including direct, reflected, and refracted signals. To suppress the shadowing effect, the receiving antenna needs to cover the entire circular mounting base. Simultaneously, due to the need for multiple channel testing, the stator antenna bandwidth must be sufficient. Considering both the metallic environment and the need for antenna miniaturization, the receiving antenna adopts a loop antenna structure, fabricated using a high-frequency circuit board. The circuit diagram is as follows... Figure 6 Design work is underway; model diagrams are available. Figure 7 .

[0035] For installation inside the engine, attach copper foil to the corresponding mounting position on the primary coil mounting bracket, place the magnetic core on the copper foil, fix the magnetic core with adhesive, wind the coil around the magnetic core, and cure in an oven at 80°C for 45 minutes. For the secondary coil mounting position, attach an insulating layer using adhesive and glass fiber, place the magnetic core on the glass fiber layer, fix the magnetic core with adhesive, and wind the coil around the magnetic core. Cure in an oven at 80°C for 16 hours.

[0036] During antenna installation, the area where the antenna will be placed on the sealing grate ring is sanded to remove the oxide layer and roughen the surface. Then, adhesive and fiberglass are used to adhere the sanded area, forming an insulating layer. After the insulating layer has cured, the antenna is glued and fixed in place with adhesive. The antenna is then placed in an oven at 80°C for 16 hours to cure.

[0037] The receiving antenna uses bolts to fix the high-frequency circuit board to the corresponding position of the receiving antenna mounting base. During installation, pay attention to the installation direction and gap control.

[0038] Install the amplifier module and AC / DC conversion module into the module mounting bracket, and install the module mounting bracket and the power supply coil (secondary side) mounting bracket on the zero-stage rotor. Install the power supply coil (primary side) and the receiving antenna mounting bracket on the adjacent stator.

Claims

1. A telemetry signal transmission system for dynamic stress of an aero-engine, characterized in that: The system includes a signal acquisition module, a signal receiving module, and a power supply module, which are installed independently within the engine. The signal acquisition module and the signal receiving module transmit signals through an antenna. The signal acquisition module includes an amplifier and a DC / AC conversion module, and the signal receiving module includes a signal receiver and a host computer. The amplifier receives and amplifies the dynamic stress signals of the engine compressor and turbine rotor, encodes and modulates them into radio frequency signals through a DC / AC conversion module, and then transmits them to the signal receiver through an antenna. The power supply module adopts a loosely coupled inductive power supply method, which transmits the power from the signal receiving module to the signal acquisition module through an inductive power supply exciter.

2. The aero-engine dynamic stress telemetry signal transmission system according to claim 1, characterized in that: The antenna includes a transmitting antenna and a receiving antenna. The transmitting antenna is connected to the DC / AC module through a parallel capacitor and an inductor, and the receiving antenna is connected to a signal receiver.

3. The aero-engine dynamic stress telemetry signal transmission system according to claim 2, characterized in that: The transmitting antenna is fixed on the outer wall of the engine's sprocket ring, and the receiving antenna is mounted on the engine stator via a receiving mounting bracket and is opposite to the transmitting antenna.

4. The aero-engine dynamic stress telemetry signal transmission system according to claim 3, characterized in that: The receiving mounting base is fixed to the engine stator by bolts, and its outer wall is in contact with the engine stator. Both its inner and outer ends are provided with support rings that are coaxial with the engine shaft. The receiving antenna is fixed to the inner support ring by bolts.

5. The aero-engine dynamic stress telemetry signal transmission system according to claim 2, characterized in that: The transmitting antenna is less than 1 / 4 wavelength in length, and the receiving antenna is a loop antenna.

6. The aero-engine dynamic stress telemetry signal transmission system according to claim 1, characterized in that: The power supply module includes a primary coil and a secondary coil. The primary coil is connected to the output terminal of the inductive power supply exciter, and the input terminal of the inductive power supply exciter draws power from the signal receiver. The secondary coil is connected to the amplifier and the DC / AC conversion module for power supply.

7. The aero-engine dynamic stress telemetry signal transmission system according to claim 6, characterized in that: A capacitor is connected in parallel between the two poles of the primary coil and the secondary coil.

8. The aero-engine dynamic stress telemetry signal transmission system according to claim 7, characterized in that: The primary and secondary coils are wound with copper wire with a diameter of 0.3mm.

9. The aero-engine dynamic stress telemetry signal transmission system according to claim 8, characterized in that: The primary coil is mounted on the outer ring of the receiving mounting base. The secondary coil is mounted between the engine zero-stage plate and the stator via the secondary coil mounting base. The amplifier and DC / AC conversion module are mounted between the engine zero-stage plate and the first-stage plate via the module mounting base. The secondary coil mounting base is coaxially mounted on the zero-stage plate, and its edge is provided with a secondary support ring coaxial with the primary coil. The secondary coil is fixed on the secondary support ring.

10. The aero-engine dynamic stress telemetry signal transmission system according to claim 9, characterized in that: Multiple module mounting bases are evenly arranged around the circumference of the zero-level disk according to the number of signal acquisition modules. Each module mounting base has two through holes that match the shapes of the amplifier and the DC / AC conversion module, respectively.

Images