Photoelectric sensor and encoder-based anti-rotation dual-rotor synchronous phase locking system and method

Abstract

The invention discloses an anti-rotation double-rotor phase locking system and method based on a photoelectric sensor and an encoder, which can realize synchronous phase locking of high-speed anti-rotation double rotors and can also be popularized to synchronous phase locking of multiple rotors. A double-phase-locking system based on a photoelectric sensor and an encoder mainly comprises a camera, a signal generator, the photoelectric sensor, a reflective patch, the encoder, a multi-channel data acquisition system and the like. The reflective patch is attached to a rotor rotating shaft, the photoelectric sensor directly faces the reflective patch, and pulse signals of the photoelectric sensor are respectively transmitted to the signal generator and the multi-channel data acquisition system. The encoders are installed at the two ends of a motor shaft and connected with the multi-channel data acquisition system. Before an experiment, an initial phase of a rotor is obtained through camera shooting; during an experiment, the photoelectric sensor outputs a pulse signal when the rotors rotate for one circle, the encoder outputs a determined number of pulse signals when the motor rotates for one circle, and the relative phase of the double rotors is finally determined by calculating the pulse number of the encoder and the photoelectric sensor.

Description

Technical Field

[0001] The invention belongs to the technical field of impeller machinery pressure measurement, and in particular relates to a counter-rotating dual-rotor synchronous phase-locking system and method based on a photoelectric sensor and an encoder. Background Art

[0002] In order to meet the development needs of modern aircraft engines, designers have proposed counter-rotation technology to improve the overall performance of the engine. The counter-rotation scheme has unique advantages: in terms of structure, due to the elimination of the stator between the two rows of rotors, under the premise of achieving the same boost ratio, the counter-rotating compressor makes the axial length of the engine shorter and lighter, which can improve the thrust-to-weight ratio of the aircraft engine. In terms of aerodynamics, due to the elimination of the stator components, the aerodynamic losses caused by factors such as friction and leakage related to it are eliminated, thereby improving the aerodynamic efficiency of the turbomachinery. In addition, the counter-rotation makes the gyroscopic torque generated by the rotors cancel each other, reducing the adverse effects of the gyroscopic torque effect on the engine and the aircraft, thereby improving the flight performance of the aircraft.

[0003] The pressure on the surface of the turbomachinery model is one of the important aerodynamic design parameters, which contains a lot of flow field information, such as shock waves, flow characteristics of leakage flow, flow separation, rotor-static interference, etc. The pressure on the model surface can be used to judge flow separation, shock wave intensity and position, which is of great significance for the analysis of flow loss mechanism. Therefore, obtaining the pressure distribution on the surface of the compressor rotor blade can provide key information for the aerodynamic design of the counter-rotating compressor, the calculation model aerodynamic load distribution, flow mechanism analysis, and verification of CFD accuracy, which is an important way to improve the performance of the compressor.

[0004] At present, the measurement methods of the surface pressure of the impeller machinery model include pressure measuring holes, pressure sensors, and new optical pressure sensitive paint pressure measurement technology. When using pressure sensors to measure the surface pressure of the impeller machinery model, rotor phase locking is required to capture unique flow phenomena, such as the trajectory of the tip leakage flow. Since the installation position of the pressure sensor is fixed, the collected pressure data only has time information, not spatial information, and the relative phase between the sensor and the rotor blade changes with the rotation of the rotor. The purpose of phase locking is to give spatial information to the pressure measured by the dynamic pressure sensor through information such as rotor speed, time and initial phase of the blade, and restore the real pressure field of the rotor channel. In addition, the optical pressure sensitive paint measurement technology usually faces the problem of insufficient image brightness and reduced signal-to-noise ratio. Due to the insufficient illumination intensity of the light source, especially in the measurement of high-speed rotating models, it is necessary to perform light source pulses in a very short time to excite the paint, so that the signal-to-noise ratio of the optical pressure sensitive paint measurement result is low. Therefore, rotor phase locking is required for image accumulation to improve the signal-to-noise ratio of the measurement result. It can be seen that rotor phase locking technology is required to obtain the surface pressure of the model in high-speed impeller machinery pressure measurement.

[0005] However, most of the current research focuses on single rotors, and there is still a lack of synchronous phase locking of dual rotors. The two rows of rotors in a counter-rotating compressor rotate in opposite directions, and the two rows of rotors can operate at different speeds. There is currently no measurement of dual rotors, and its actual flow characteristics are unclear, and it is impossible to study the flow mechanism on the surface of the dual rotor blades from an experimental perspective. Therefore, how to achieve synchronous phase locking of the dual rotors of a counter-rotating compressor is the primary problem that needs to be solved in the surface pressure measurement of the counter-rotating compressor model. In addition, when studying the physical model of two counter-rotating components such as a counter-rotating compressor, the relative phase of the two rotors needs to be considered, but how to convert the pressure data under time into space and time to obtain the spatial distribution of pressure and then restore it to the real flow field has become a difficulty faced by dynamic measurement.

[0006] Therefore, in order to address the above problems, it is necessary to develop a synchronous phase-locking method suitable for the counter-rotating dual rotors of a counter-rotating compressor to solve the problem of synchronous measurement of the surface pressure of the dual rotors of the impeller machinery. Summary of the invention

[0007] In order to solve the phase-locking problem faced by the surface pressure measurement of the counter-rotating dual-rotor model of the impeller machinery, the present invention provides a counter-rotating dual-rotor synchronous phase-locking system and method based on photoelectric sensors and encoders, which can effectively solve the above problems.

[0008] The present invention provides a counter-rotating dual-rotor synchronous phase-locking system and method based on a photoelectric sensor and an encoder, which mainly solves the problem of counter-rotating dual-rotor synchronous phase-locking and has the function of dual-rotor synchronous multi-phase regulation.

[0009] A counter-rotating dual-rotor synchronous phase-locking system based on photoelectric sensors and encoders, characterized in that it includes a dual phase-locking system based on photoelectric sensors and encoders, and is mainly composed of a CCD camera, a signal generator, a photoelectric sensor, a reflective patch, an encoder, a multi-channel data acquisition system, a signal transmission line, a computer, etc. The reflective patch is applied to the rotor rotating shaft, and the photoelectric sensor is directly opposite to the reflective patch. The pulse signal of the photoelectric sensor is transmitted to the signal generator and the multi-channel data acquisition system respectively. On the one hand, the signal can be used to control the light source and the camera shooting when measuring optical pressure-sensitive coatings, and on the other hand, it is used to freeze the phase of the rotor. The encoder is installed at one end of the motor shaft, connected to the multi-channel data acquisition system, and combined with the pulse signal of the photoelectric sensor, the dual rotor phase lock is realized together.

[0010] A method for synchronous phase locking of counter-rotating dual rotors based on photoelectric sensors and encoders, the steps are as follows:

[0011] (1) In order to obtain the target rotor blade initial phase, the rotor blade needs to be phase-locked before the experiment;

[0012] (2) Each time the reflective patch scans the photoelectric sensor, the photoelectric sensor emits a laser to illuminate the reflective patch and receives the reflection signal of the reflective patch. The pulse signal is transmitted to the signal generator through the signal transmission line as an external trigger signal of the camera, which is used to control the camera to shoot. At this time, the camera will simultaneously capture multiple rotor blades, and select one of the rotor blades as the target blade.

[0013] (3) During the experiment, the pulse signal of the photoelectric sensor is transmitted to the multi-channel data acquisition system to record the timing information of the pulse signal of the photoelectric sensor.

[0014] (4) When the motor rotates one circle, the encoder outputs a certain number of pulse signals, which are transmitted to the multi-channel data acquisition system to record the timing information of the encoder pulse signals.

[0015] (5) Combining the pulse signals of the photoelectric sensor and the encoder, the relative phase of the dual rotors is finally determined by calculating the number of encoder and photoelectric sensor pulses.

[0016] By adopting the above technical solution, the present invention has the following beneficial effects:

[0017] The present invention proposes a counter-rotating dual-rotor synchronous phase-locking system and method based on a photoelectric sensor and an encoder, and its beneficial effects are as follows:

[0018] (1) Based on the photoelectric sensor and encoder, it can not only realize the synchronous phase locking of two rotors rotating in opposite directions, but also be applicable to the synchronous phase locking of two rotors rotating in the same direction, and can also be extended to the synchronous phase locking of multiple rotors;

[0019] (2) It can effectively solve the phase-locking problem when measuring the surface pressure of a high-speed rotating model of an impeller machine;

[0020] (3) This measurement method only requires a reflective patch to be attached to the rotating shaft. The installation structure is simple and does not interfere with the flow field or damage the aerodynamic layout of the impeller machinery.

[0021] (4) The phase-locking system based on photoelectric sensors and encoders has high phase-locking accuracy and good economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific implementation of the present invention or the technical solution in the prior art, the following will introduce the drawings required for the specific implementation or the prior art description. For ordinary technicians in this field, other drawings can also be obtained based on these drawings without creative work. Figure 1 Schematic diagram of the counter-rotating dual-rotor synchronous phase-locked system based on photoelectric sensors and encoders. Figure 2 This is the principle diagram of the counter-rotating dual-rotor synchronous phase-locking based on photoelectric sensors and encoders.

[0023] Explanation of the numbers in the figure: front rotor (R1) 1, rear rotor (R2) 2, reflective patches 3 and 24, photoelectric sensors 4 and 23, gearboxes 5 and 22, motors 6 and 21, encoders 7 and 20, rotating shafts 8 and 19, signal transmission lines 9, 10, 17 and 18, signal generators 11 and 16, computer 12, multi-channel signal acquisition system 13, cameras 14 and 15. DETAILED DESCRIPTION

[0024] The following further describes the counter-rotating dual-rotor synchronous phase-locking system and method based on photoelectric sensors and encoders in combination with specific examples and drawings. The described embodiments are only part of the embodiments of the present invention, but not all of them.

[0025] The present invention proposes a counter-rotating dual-rotor synchronous phase-locking system and method based on photoelectric sensors and encoders, which are mainly used for the dual-rotor synchronous phase-locking of high-speed rotating models of impeller machinery, and solves the problem of phase-locking difficulties when measuring the surface pressure of the impeller machinery model. This method has the advantages of not destroying the aerodynamic layout and geometric structure of the impeller machinery, high phase-locking accuracy, and good economy. It has the function of adjusting the rotor phase at will, and can not only realize the synchronous phase-locking of dual rotors rotating in opposite directions, but is also suitable for the synchronous phase-locking of dual rotors rotating in the same direction, and can also be extended to the synchronous phase-locking of multiple rotors.

[0026] The anti-rotating dual-rotor synchronous phase-locking system based on photoelectric sensors and encoders established by the present invention mainly comprises a dual phase-locking system based on photoelectric sensors and encoders, and is mainly composed of a front rotor (1), a rear rotor (2), reflective patches (3) and (24), photoelectric sensors (4) and (23), a gearbox (5) and (22), a motor (6) and (21), an encoder (7) and (20), a rotating shaft (8) and (19), signal transmission lines (9), (10), (17) and (18), a signal generator (11) and (16), a computer (12), a multi-channel signal acquisition system (13), a camera (14) and (15), etc. The specific system composition and connection method are as follows. Figure 1 As shown, the specific connection and fixing methods of the system components are as follows:

[0027] Photoelectric sensors (4) and (23) are respectively fixed on the bases of the gearboxes (5) and (22), facing the rotor rotating shafts (8) and (19), and reflective patches (3) and (24) are respectively attached to the rotor rotating shafts to reflect the laser light emitted by the photoelectric sensors, so as to achieve phase-locked triggering.

[0028] The encoders (7) and (20) are respectively mounted on the tail shaft of the motor and are combined with the photoelectric sensor to determine the relative phase of the double rotor blades.

[0029] The photoelectric sensors (4) and (23) are connected to the external trigger signal TRIG ports of the signal generators (11) and (16) through signal transmission lines (9) and (18), respectively. The pulse signals of the photoelectric sensors are used for synchronous phase locking of the dual rotor blades and as external trigger signals for camera shooting. In addition, the pulse signals of the photoelectric sensors (4) and (23) are respectively transmitted to the multi-channel data acquisition system (13); the encoders (7) and (20) transmit the pulse signals to the multi-channel data acquisition system (13) through signal transmission lines (10) and (17), respectively, and the relative phases of the dual rotor blades are determined in combination with the pulse signals of the photoelectric sensors.

[0030] The present invention provides a counter-rotating dual-rotor synchronous phase-locking method based on a photoelectric sensor and an encoder, which is specifically implemented as follows:

[0031] 1) The phase-locking principle and process of the photoelectric sensor: Every time the reflective patch scans the photoelectric sensor, the photoelectric sensor emits a laser to illuminate the reflective patch, and receives the reflective signal of the reflective patch. The TTL signal is transmitted to the signal generator through the signal transmission line as the external trigger phase-locking signal of the blade to lock the phase of the rotor blade. The signal is transmitted to the camera through the CH1 port of the signal generator to control the camera to shoot. The photoelectric sensor sends a pulse signal when the blade rotates one circle, and the number of pulses output by the photoelectric sensor is recorded as No.

[0032] 2) Before the experiment, in order to obtain the initial phase of the two rows of rotors, it is necessary to determine the phase-locked position of the two rows of rotors by taking pictures with a camera;

[0033] 3) Based on the phase-locked principle of the photoelectric sensor, the rotor (1) is rotated before the experiment. Each time the reflective patch (24) scans the photoelectric sensor (23), the photoelectric sensor sends a pulse signal which is transmitted to the signal generator (16). Then, the camera (15) is controlled to take pictures through the CH1 port of the signal generator. At this time, multiple rotor blades are photographed, and a certain blade is selected as the target blade, thereby obtaining the initial phase of the rotor (1). Based on the above phase-locked acquisition principle, the initial phase of the rotor (2) can be obtained.

[0034] 4) When motors (6) and (21) rotate one circle, encoders (7) and (20) respectively output a certain number of pulse signals, denoted as Ne, which are respectively transmitted to a multi-channel data acquisition system (13) through signal transmission lines (10) and (17) to record the timing information of the encoder pulse signals.

[0035] The following is for Figure 2 As shown, a counter-rotating dual-rotor synchronous phase-locking method based on photoelectric sensors and encoders is specifically described.

[0036] When the blade rotates one circle, the number of encoder output pulses is Noe, which is calculated based on the output speed ratio Sr of the gearbox. The calculation method is as follows.

[0037] Sr=Ne / Noe

[0038] When the photoelectric sensor of rotor R1 outputs a pulse signal, the encoder (20) outputs a pulse number Noe1; when the photoelectric sensor of rotor R2 outputs a pulse signal, the encoder (7) outputs a pulse number Noe2. The absolute phase corresponding to one pulse interval of the encoder is Δθ, which is calculated as follows.

[0039] Δθ=2π / Noe

[0040] From the above, we can get the current absolute phase θ1 of the rotor R1. The calculation method is as follows: B1 Indicates the number of blades of rotor R1.

[0041]

[0042] The current absolute phase θ2 of rotor R2 is calculated as follows: B2 Indicates the number of blades of rotor R2.

[0043]

[0044] Finally, the relative phase θ of the two rows of rotors can be obtained 12 , the calculation method is as follows.

[0045] θ 12 =θ1-θ2

[0046] The present invention proposes a counter-rotating dual-rotor synchronous phase-locking system and method based on photoelectric sensors and encoders, which can not only realize the synchronous phase-locking of dual rotors rotating in opposite directions, but also realize the synchronous phase-locking of dual rotors rotating in the same direction. It can also be extended to the synchronous phase-locking of multiple rotors, which can solve the phase-locking problem when measuring the surface pressure of the impeller machinery model. In addition, the phase-locking method only needs to apply reflective stickers on the rotating shaft during actual measurement, which is convenient for actual processing and installation, saving experimental costs. It does not interfere with the flow field and does not destroy the aerodynamic layout of the impeller machinery. In addition, the dual-rotor synchronous locking method based on photoelectric sensors and encoders has high phase-locking accuracy, can realize the phase-locking of high-speed rotating models, and has the function of adjustable phase of multiple rotors.

[0047] Finally, it should be noted that the above is only a specific implementation method of the present disclosure and is only used to illustrate the technical solution of the present invention, but the protection scope of the present disclosure is not limited to this. Any technician familiar with the technical field can easily modify or replace it within the technical scope disclosed in the present disclosure, and it should be covered by the protection scope of the present disclosure.

Claims

1. A counter-rotating dual-rotor synchronous phase-locking system based on photoelectric sensors and encoders, mainly comprising a dual phase-locking system based on photoelectric sensors and encoders, mainly composed of a front rotor R1 (1), a rear rotor R2 (2), reflective patches (3) and (24), photoelectric sensors (4) and (23), a gearbox (5) and (22), a motor (6) and (21), an encoder (7) and (20), a rotating shaft (8) and (19), a signal transmission line (9), (10), (17) and (18), a signal generator (11) and (16), a computer (12), a multi-channel signal acquisition system (13), a camera (14) and (15), etc. The specific system composition and connection method are shown in Figure 1, and the specific connection and fixing method of the system composition are as follows: 1) Photoelectric sensors (4) and (23) are respectively fixed on the bases of the gearboxes (5) and (22), facing the rotor rotating shafts (8) and (19), and reflective patches (3) and (24) are respectively attached to the rotor rotating shafts to reflect the laser emitted by the photoelectric sensors, so as to achieve phase-locked triggering. 2) Encoders (7) and (20) are respectively installed on the tail shaft of the motor end and combined with the photoelectric sensor to determine the relative phase of the dual rotor blades. 3) The photoelectric sensors (4) and (23) are connected to the external trigger signal TRIG ports of the signal generators (11) and (16) through signal transmission lines (9) and (18), respectively. The pulse signals of the photoelectric sensors are used for synchronous phase locking of the dual rotor blades and as external trigger signals for camera shooting. In addition, the pulse signals of the photoelectric sensors (4) and (23) are respectively transmitted to the multi-channel data acquisition system (13); the encoders (7) and (20) transmit the pulse signals to the multi-channel data acquisition system (13) through signal transmission lines (10) and (17), respectively, and the relative phase of the dual rotor blades is determined in combination with the pulse signals of the photoelectric sensors.

2. A method for synchronous phase locking of counter-rotating dual rotors based on photoelectric sensors and encoders implemented by the measurement system according to claim 1, characterized in that: The steps are as follows: Step 1: The phase-locking principle and process of the photoelectric sensor: Every time the reflective patch scans the photoelectric sensor, the photoelectric sensor emits a laser to illuminate the reflective patch, and receives the reflective signal of the reflective patch. The TTL signal is transmitted to the signal generator through the signal transmission line as the external trigger phase-locking signal of the blade to lock the phase of the rotor blade. The signal is transmitted to the camera through the CH1 port of the signal generator to control the camera to shoot. The photoelectric sensor sends a pulse signal when the blade rotates one circle, and the number of pulses output by the photoelectric sensor is recorded as No. Step 2: Before the experiment, in order to obtain the initial phase of the two rows of rotors, it is necessary to determine the phase-locked position of the two rows of rotors by taking pictures with a camera; Step 3: Based on the phase-locked principle of the photoelectric sensor, the rotor (1) is rotated before the experiment. Each time the reflective patch (24) scans the photoelectric sensor (23), the photoelectric sensor sends a pulse signal which is transmitted to the signal generator (16). Then, the camera (15) is controlled to take pictures through the CH1 port of the signal generator. At this time, multiple rotor blades are photographed, and a blade is selected as the target blade. Thus, the initial phase of the rotor (1) can be obtained. Based on the above phase-locked acquisition principle, the initial phase of the rotor (2) can be obtained. Step 4: When motors (6) and (21) rotate one circle, encoders (7) and (20) respectively output a certain number of pulse signals, denoted as Ne, which are respectively transmitted to a multi-channel data acquisition system (13) through signal transmission lines (10) and (17), and the timing information of the encoder pulse signals is recorded. Step 5: As shown in Figure 2, the counter-rotating dual-rotor synchronous phase-locking method based on photoelectric sensors and encoders is specifically described. When the blade rotates one circle, the number of encoder output pulses is Noe, which is calculated based on the output speed ratio Sr of the gearbox, and the calculation method is as follows. Sr=Ne / Noe Step 6: When the photoelectric sensor of rotor R1 outputs a pulse signal, the encoder (20) outputs a pulse number Noe1; when the photoelectric sensor of rotor R2 outputs a pulse signal, the encoder (7) outputs a pulse number Noe2. The absolute phase corresponding to one pulse interval of the encoder is Δθ, which is calculated as follows. Δθ=2π / Noe Step 7: From the above, we can get the current absolute phase θ1 of the rotor R1. The calculation method is as follows: B1 Indicates the number of blades of rotor R1. Step 8: The current absolute phase θ2 of rotor R2 is calculated as follows: B2 Indicates the number of blades of rotor R2. Step 9: Finally, the relative phase θ of the two rows of rotors can be obtained 12 , the calculation method is as follows. i 12 =θ1-θ2.

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