Rotor rotating speed signal processor with dual-mode criterion

Abstract

The invention discloses a rotor rotating speed signal processor with dual-mode criteria, which is characterized in that a power circuit board and a processing circuit board are arranged on the rotor rotating speed signal processor, and the rotor rotating speed signal processor collects frequency signals of a rotor rotating speed magnetic sensor; after a sensor signal is processed, an alarm signal indicating whether the rotating speed of the rotor is high or low is provided for an alarm module and an electromechanical management system, and a mode criterion signal input to the electromechanical management system is added to input a changeable rotor rotating speed qualification criterion, so that dual judgment of rotor rotating speed qualification in a helicopter mode and a fixed wing mode is realized. The power supply module adopts a plurality of filtering units and a plurality of energy storage units, so that the problems that the rotor rotating speed of a helicopter mode and a fixed wing mode cannot be judged to be qualified and the frequency and voltage conversion high precision and anti-EMI (Electro-Magnetic Interference) cannot be realized in an existing rotor rotating speed signal processor are solved, and the frequency value of the rotor rotating speed of an airplane is accurately and truly reflected; and the anti-EMI capability of the processor and the overall reliability of the system are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of rotor control, and in particular relates to a rotor speed signal processor with dual-mode criterion. Background Art

[0002] The rotor speed signal processor is a core system that ensures the safe operation of rotorcraft propulsion systems, and its technological evolution is closely linked to the development of avionics systems. Early speed monitoring used mechanical centrifugal governors, which were limited by response speed and accuracy and were gradually replaced by electronic systems. In the 1990s, digital processors based on Hall-effect sensors became mainstream, calculating speed through pulse frequency measurement. Typical architectures include analog front-end conditioning circuits and 8-bit microcontrollers, but their resistance to electromagnetic interference was insufficient, resulting in a high false alarm rate under complex operating conditions.

[0003] With the increasing demand for avionics integration, its technological development focuses on high reliability, real-time performance and environmental robustness. Modern designs use mixed-signal design, integrated high-precision timers and hardware CRC check units to shorten response time. The threshold comparison algorithm is combined with the signal processing algorithm of speed gradient prediction to achieve speed signal protection and improve processor reliability.

[0004] Furthermore, the weak signal output by the magnetic sensor collected by the rotor speed signal processor is easily overwhelmed by electromagnetic noise and easily interfered with by power supply noise, resulting in electromagnetic interference problems. This can ultimately cause speed signal glitches, jumps, or even loss. This makes it difficult to achieve dual determination of rotor speed eligibility in both helicopter and fixed-wing modes, achieve high-precision frequency and voltage conversion in dual modes, and address EMI issues. Therefore, there is an urgent need to provide a rotor speed signal processor with dual-mode judgment criteria to address these technical issues. Summary of the Invention

[0005] In view of this, the present invention provides a rotor speed signal processor with dual-mode judgment, which can accurately and truly reflect the frequency value of the aircraft rotor speed, improve the processor's anti-EMI capability, and enhance the overall reliability of the system. It is specifically implemented by the following technical solution.

[0006] The present invention provides a rotor speed signal processor with dual-mode judgment, comprising a housing, a power circuit board disposed at the bottom of the housing, an inter-board connector disposed on the power circuit board, and a processing circuit board located on the inter-board connector. An electrical connector for connecting multiple rotor speed magnetic sensors is disposed on a side of the housing. The power circuit board includes a power module and a voltage adjustment module. The power module includes a rectifier unit connected to a power input end, a first energy storage unit, a first filter unit, and a second energy storage unit. The first energy storage unit and the first filter unit are both connected to the rectifier unit. The first filter unit is connected to one end of the second energy storage unit, and the other end of the second energy storage unit is connected to the voltage adjustment module. The processing circuit board includes a detection module connected to the plurality of rotor speed magnetic sensors, a main control module connected to the detection module, an alarm module, and a mode judgment signal input module. The voltage adjustment module, the alarm module, and the mode judgment signal input module are all connected to the main control module. The mode judgment signal input module is used to connect to the motor management system and receive the mode judgment signal of the motor management system. Among them, the power supply module and the voltage adjustment module are used to supply power to the main control module, the main control module controls the detection module to detect the connection status of the rotor speed magnetic sensor and the rotor speed signal processor, and receives the speed acquisition signal and the mode judgment signal of the rotor speed magnetic sensor according to the connection status, the main control module processes the speed acquisition signal and the mode judgment signal and controls the on and off of the alarm module.

[0007] As a preferred embodiment of the above technical solution, the voltage adjustment module includes a DCDC converter connected to the second energy storage unit, a second filtering unit and a low voltage difference three-terminal voltage regulator, one end of the second filtering unit is connected to the DCDC converter, and the other end of the second filtering unit is connected to the low voltage difference three-terminal voltage regulator, and the low voltage difference three-terminal voltage regulator is connected to the main control module.

[0008] As a preferred embodiment of the above technical solution, the rectifier unit includes a diode D19, the first energy storage unit includes a capacitor C48, the first filtering unit includes a common-mode suppression inductor T1, a capacitor C36, a capacitor C37 and a filter IC11, the anode of the diode D19 is used to access the power input terminal, the cathode of the diode D19 is connected to the capacitor C48 and one end of the common-mode suppression inductor T1, the other end of the common-mode suppression inductor T1 is respectively connected to the capacitor C36 and the capacitor C37, and the capacitor C36 and the capacitor C37 are both connected to the filter IC11; The second energy storage unit includes capacitor C38, capacitor C39, capacitor C40, diode D20, diode D21 and resistor R38, the anode of diode D20, capacitor C38 and capacitor C39 are all connected to filter IC11, and the cathode of diode D21 is connected to resistor R38, capacitor C40 and cathode of diode D21; The DCDC converter includes a chip IC10, the second filtering unit includes a capacitor C41, a capacitor C42, a capacitor C43, a capacitor C44, a capacitor C45, a capacitor C46 and a capacitor C47, capacitor C41 and capacitor C42 are connected in parallel, capacitor C43 and capacitor C44 are connected in parallel, capacitor C46 and capacitor C47 are connected in parallel to chip IC10 and are respectively connected to chip IC10, the low voltage difference three-terminal voltage regulator includes a chip IC12, a capacitor C49, a capacitor C50, a capacitor C51 and a capacitor C52, capacitor C49, capacitor C50, capacitor C51 and capacitor C52 are connected in parallel to chip IC12.

[0009] As a preferred embodiment of the above technical solution, the first energy storage unit and the second energy storage unit both use high-energy tantalum capacitors, and the capacitance values ​​of capacitors C41, C43 and C46 are greater than the capacitance values ​​of capacitors C36, C37, C39, C40, C42, C44, C45 and C47.

[0010] As a preferred embodiment of the above technical solution, the detection module includes a self-test signal switching circuit connected to the rotor speed magnetic sensor and a filter circuit, an amplification circuit and a clamping circuit connected in sequence, and the filter circuit and the main control module are both connected to the self-test signal switching circuit; The self-test signal switching circuit is used to perform a power-on BIT test on the rotor speed magnetic sensor, the filtering circuit is used to filter the input frequency signal of the self-test signal switching circuit, the amplifying circuit is used to amplify the filtered signal and shape the amplified signal into a square wave signal, and the clamping circuit is used to process the square wave signal and send it to the main control module.

[0011] As a preferred embodiment of the above technical solution, the alarm module includes an alarm switch circuit connected to the main control module and an alarm control light box connected to the alarm switch circuit, the alarm switch circuit includes a relay, a diode and an inductor, and the alarm switch circuit is used to receive the output level of the main control module; When the clamping circuit clamps the level of the square wave signal to the input range of the main control module, the main control module performs calculation processing on the speed acquisition signal corresponding to the input frequency signal to obtain a corresponding speed input signal; The main control module performs judgment and processing based on the speed input signal and the mode criterion signal to obtain an output level. The main control module controls the on and off of the alarm control light box through the alarm switch circuit based on the output level, wherein the mode criterion signal includes fixed-wing mode judgment, helicopter and transition mode judgment.

[0012] As a preferred embodiment of the above technical solution, the mode judgment signal input module includes an RS422 communication circuit connected to the main control module, and the RS422 communication circuit is used to transmit the speed value processed by the main control module to the motor management system, and send the mode judgment signal of the motor management system to the main control module.

[0013] As a preferred embodiment of the above technical solution, the main control module controls the detection module to detect the connection status between the rotor speed magnetic sensor and the rotor speed signal processor, including: The main control module sends a power-on self-test instruction to the detection module, and the detection module detects whether there is a signal input from the input interface of the rotor speed magnetic sensor; If there is no signal input, the main control module sets an input frequency self-test signal to control the rotor speed magnetic sensor to connect to the speed measurement channel, and the main control module receives the speed acquisition signal of the speed measurement channel to perform a calculation and determine whether the speed measurement channel is normal, wherein each rotor speed magnetic sensor includes one speed measurement channel; If normal, the main control module selects the capture frequency corresponding to the speed acquisition signal according to the lowest measurement frequency of the rotor speed magnetic sensor, wherein the capture frequency determines the frequency signal change rate according to the engine speed change rate and is calculated using a threshold comparison algorithm and a speed gradient prediction algorithm.

[0014] As a preferred embodiment of the above technical solution, the detection module is further used to detect the input level of the AD interface of the main control module to determine whether the working power supply of the main control module is normal; If normal, the detection module is further configured to detect the received data and the sent data of the communication interface of the main control module and compare them to determine whether the communication interface of the main control module is normal.

[0015] As a preferred embodiment of the above technical solution, the rotor speed signal processor also includes a cover plate and a limit assembly arranged on the shell, the limit assembly includes a flat washer arranged on the side of the shell, a spring washer and a pan head screw attached to the flat washer, one end of the pan head screw is connected to the electrical connector, and the other end of the pan head screw is used to fix the spring washer and the flat washer.

[0016] The present invention provides a rotor speed signal processor with dual-mode judgment. By arranging a power circuit board and a processing circuit board on the rotor speed signal processor, the rotor speed signal processor collects the frequency signal of the rotor speed magnetic sensor, processes the sensor signal, and provides an alarm signal of high rotor speed or low rotor speed to the alarm module and the electromechanical management system after processing. Adding a mode judgment signal input module to the electromechanical management system can change the rotor speed qualification judgment criterion, and realize dual judgment of the rotor speed qualification in helicopter mode and fixed-wing mode. The power supply module adopts multiple filtering units and multiple energy storage units, which solves the problem that the existing rotor speed signal processor cannot realize dual judgment of the rotor speed qualification in helicopter mode and fixed-wing mode, high precision of frequency and voltage conversion in dual mode, and anti-EMI. It can accurately and truly reflect the frequency value of the aircraft rotor speed, improve the processor's anti-EMI capability, and enhance the overall reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 This is a structural block diagram of the rotor speed signal processor provided by the present invention; Figure 2 A schematic diagram of the structure of the rotor speed signal processor provided by the present invention; Figure 3 A circuit schematic diagram of the rotor speed signal processor provided by the present invention; Figure 4 A circuit diagram of the power circuit board provided by the present invention; Figure 5 A structural block diagram of the voltage adjustment module provided by the present invention; Figure 6 A structural block diagram of the detection module provided by the present invention; Figure 7 This is a main working flow diagram of the rotor speed signal processor provided by the present invention.

[0019] The main component symbols are described as follows: 10-housing; 20-power circuit board; 30-inter-board connector; 40-processing circuit board; 50-electrical connector; 60-power module; 70-voltage adjustment module; 80-rectifier unit; 90-first energy storage unit; 100-first filtering unit; 110-second energy storage unit; 120-detection module; 130-main control module; 140-alarm module; 150-mode judgment signal input module; 160-DCDC converter; 170-second filtering unit; 180-low voltage difference three-terminal voltage regulator; 190-self-test signal switching circuit; 200-filtering circuit, 210-amplifier circuit; 220-clamping circuit; 230-cover; 240-limiting assembly; 250-pan head screw; 260-nut; 270-conductive rubber ring; 280-countsunk screw. DETAILED DESCRIPTION

[0020] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0021] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be an intermediate element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. Conversely, when an element is referred to as being "directly on" another element, there is no intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only.

[0022] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0023] In order to realize the addition of speed judgment switching function to the rotor speed signal processor, one RS422 communication is used for full-duplex communication. For the switching of "helicopter and transition mode" and "fixed-wing mode" instructions, the rotor speed signal processor gives priority to the data of the RS422 communication interface. If a communication failure occurs, the discrete quantity instruction (corresponding to Figure 3The switch signals of the fixed-wing mode judgment, helicopter and transition mode judgment are convenient for balancing data real-time performance and ensuring functional safety integrity. Common-mode suppression inductors, EMI filters and filter capacitors are added to the power circuit board to improve anti-EMI capabilities.

[0024] See Figure 1 、 Figure 2 and Figure 3 The present invention provides a rotor speed signal processor with dual-mode judgment. The rotor speed signal processor includes a housing 10, a power circuit board 20 disposed at the bottom of the housing 10, an inter-board connector 30 disposed on the power circuit board 20, and a processing circuit board 40 located on the inter-board connector 30. An electrical connector 50 for connecting multiple rotor speed magnetic sensors is disposed on the side of the housing 10. The power circuit board 20 includes a power module 60 and a voltage adjustment module 70. The power module 60 includes a rectifier unit 80 for connecting to a power input terminal, a first energy storage unit 90, a first filter unit 100, and a second energy storage unit 110. The first energy storage unit 90 and the first filter unit 100 are both connected to the rectifier unit 80. The first filter unit 100 is connected to one end of the second energy storage unit 110. The other end of the second energy storage unit 110 is connected to the voltage adjustment module 70. The processing circuit board 40 includes a detection module 120 connected to the plurality of rotor speed magnetic sensors, a main control module 130 connected to the detection module 120, an alarm module 140, and a mode judgment signal input module 150. The voltage adjustment module 70, the alarm module 140, and the mode judgment signal input module 150 are all connected to the main control module 130. The mode judgment signal input module 150 is used to connect to the motor management system and receive the mode judgment signal of the motor management system. Among them, the power supply module 60 and the voltage adjustment module 70 are used to supply power to the main control module 130. The main control module 130 controls the detection module 120 to detect the connection status between the rotor speed magnetic sensor and the rotor speed signal processor, and receives the speed acquisition signal and the mode judgment signal of the rotor speed magnetic sensor according to the connection status. The main control module 130 processes the speed acquisition signal and the mode judgment signal and controls the on and off of the alarm module 140.

[0025] In this embodiment, the rotor speed signal processor also includes a cover plate 230 and a limit assembly 240 arranged on the shell 10. The limit assembly 240 includes a flat washer arranged on the side of the shell 10, a spring washer and a pan head screw 250 attached to the flat washer. One end of the pan head screw 250 is connected to the electrical connector 50, and the other end of the pan head screw 250 is used to fix the spring washer and the flat washer. The pan head screw 250 is fixed to the side of the shell 10 through a nut 260, and the cover plate 230 is fixed to the shell 10 through a countersunk screw 280. The electrical connector 50 is connected to the power circuit board 20 or the processing circuit board 40 in the shell 10 through a conductive rubber ring 270. The rotor speed signal processor includes two circuit boards, one of which is the power circuit board 20 and the other is the processing circuit board 40. The power circuit board 20 plays an anti-EMI role. The power output by the power circuit board 20 is the processed power. The power circuit board 20 mainly consists of a common mode suppression inductor T1, a filter with DC surge protection function (EMI filter, Figure 4 The circuit consists of IC11 in the circuit), an energy storage capacitor, a DC-DC converter, and filter capacitors. Common-mode suppression inductor T1 at the positive power input suppresses differential-mode interference signals. Rectifier diode D19 ensures that the product (rotor speed signal processor) is de-energized and does not suffer damage if the power input is reversed. Furthermore, if the product loses power or input power is lost, the internal energy storage capacitor C48 discharges, preventing feedback to the onboard power grid. An EMI filter and resistor-capacitor components (resistor R38 and capacitor C38) filter the primary and secondary power supplies, reducing mutual interference between the onboard power supply and the rotor speed signal processor, thereby meeting the product's electromagnetic compatibility requirements.

[0026] It should be noted that, please refer again Figure 4 and Figure 5 The voltage adjustment module 70 includes a DCDC converter 160, a second filtering unit 170, and a low-voltage dropout three-terminal voltage regulator 180 connected to the second energy storage unit 110. One end of the second filtering unit 170 is connected to the DCDC converter 160, and the other end of the second filtering unit 170 is connected to the low-voltage dropout three-terminal voltage regulator 180. The low-voltage dropout three-terminal voltage regulator 180 is connected to the main control module 130. The rectifier unit 80 includes a diode D19, the first energy storage unit 90 includes a capacitor C48, and the first filtering unit 100 includes a common-mode suppression inductor T1, a capacitor C36, a capacitor C37, and a filter IC11. The anode of the diode D19 is used to connect to the power input terminal, and the cathode of the diode D19 is connected to one end of the capacitor C48 and the common-mode suppression inductor T1. The other end of the common-mode suppression inductor T1 is connected to the capacitor C36 and the capacitor C37 respectively. The capacitors C36 and C37 are both connected to the filter IC11. The second energy storage unit 110 includes a capacitor C38, a capacitor C39, a capacitor C40, a diode D20, a diode D21 and a resistor R38. The anode of the diode D20, the capacitor C38 and the capacitor C39 are all connected to the filter IC11, and the cathode of the diode D21 is connected to the resistor R38, the capacitor C40 and the cathode of the diode D21. The DCDC converter 160 includes a chip IC10, and the second filtering unit 170 includes a capacitor C41, a capacitor C42, a capacitor C43, a capacitor C44, a capacitor C45, a capacitor C46 and a capacitor C47. The capacitor C41 is connected in parallel with the capacitor C42, the capacitor C43 and the capacitor C44 are connected in parallel, and the capacitor C46 and the capacitor C47 are connected in parallel to the chip IC10 and are respectively connected to the chip IC10. The low voltage difference three-terminal voltage regulator 180 includes a chip IC12, a capacitor C49, a capacitor C50, a capacitor C51 and a capacitor C52. The capacitor C49, the capacitor C50, the capacitor C51 and the capacitor C52 are connected in parallel to the chip IC12.

[0027] Among them, the first energy storage unit 90 and the second energy storage unit 110 both use high-energy tantalum capacitors. The capacitance values ​​of capacitors C41, C43, and C46 are greater than the capacitance values ​​of capacitors C36, C37, C39, C40, C42, C44, C45, and C47. A filter (ZMEMI type IC11) is selected. The filter has an input voltage range of 0V to 50V, a maximum surge voltage of 80V / 50ms, and a common-mode insertion loss of filter IC11 of 35dB / 500KHz. The filter capacitor uses 10uF ( Figure 4 C41, C43, C46) and 0.01uF ( Figure 4 C36, C37, C39, C40, C42, C44, C45, C47) in the circuit serve as input filter capacitors to effectively filter out low-frequency and high-frequency interference in the circuit. Figure 4 In the figure, Positive Input indicates the positive input terminal, Input Common indicates the input common, Case Ground indicates the case ground, Main (+5) Ouput indicates the main output +5V voltage, Pos.Aux.Output indicates the positive auxiliary output, Output Common indicates the output common, and Neg.Aux.Output indicates the negative auxiliary output.

[0028] The energy storage capacitor (C38) uses a high-energy tantalum capacitor (THCL type), which can provide power to the product when the external power supply is off, so that the product can work normally in the case of a 50ms power outage. Due to the large capacity of the capacitor, the current is too large when charging, so a slow charge and fast discharge control circuit is required (tantalum capacitor C38 can achieve the function of slow charge and fast discharge) to prevent the system power supply from being impacted by the power-on moment. A DCDC converter (ZHF type) is selected ( Figure 4 IC10 in the figure can achieve 16V to 48V input, +5V and ±15V output, and 15W power, providing a stable power supply for the rotor speed signal processor. The power module 60 is manufactured using a thick-film hybrid integrated process and is housed in a fully sealed metal housing. It features input undervoltage, disable, and short-circuit protection, and can withstand 80V / 1s surges, meeting product design requirements. 10uF output filter capacitors (C41, C43, and C46) effectively filter out low- and high-frequency interference in the circuit. The DC-DC converter 160 outputs the +5V circuit through a low-dropout three-terminal voltage regulator 180 ( Figure 4 IC12 in the circuit converts the voltage to +3.3V, which is used to power the main control module 130 and the level shifter chip. IC10 converts 28V to +5V (pin 2) and ±15V outputs (pins 4 and 5). IC12 can be a level shifter chip that converts +5V to +3.3V.

[0029] It should be understood that by setting a power supply circuit board 20 and a processing circuit board 40 on the rotor speed signal processor, the rotor speed signal processor collects the frequency signal of the rotor speed magnetic sensor, processes the sensor signal, and provides an alarm signal of high rotor speed or low rotor speed to the alarm module 140 and the electromechanical management system after processing. Adding a mode judgment signal input module 150 to the electromechanical management system can change the rotor speed qualification criterion to achieve dual judgment of the rotor speed qualification in helicopter mode and fixed-wing mode. The power supply module 60 adopts multiple filtering units and multiple energy storage units, which solves the problems of the existing rotor speed signal processor that cannot achieve dual judgment of the rotor speed qualification in helicopter mode and fixed-wing mode, high precision of frequency and voltage conversion in dual modes, and anti-EMI. It can accurately and truly reflect the frequency value of the aircraft rotor speed, improve the processor's anti-EMI capability, and enhance the overall reliability of the system.

[0030] Optionally, the detection module 120 includes a self-test signal switching circuit 190 connected to the rotor speed magnetic sensor, and a filter circuit 200, an amplification circuit 210, and a clamping circuit 220 connected in sequence. The filter circuit 200 and the main control module 130 are both connected to the self-test signal switching circuit 190. The self-test signal switching circuit 190 is used to perform a power-on BIT test on the rotor speed magnetic sensor, the filtering circuit 200 is used to filter the input frequency signal of the self-test signal switching circuit 190, the amplifying circuit 210 is used to amplify the filtered signal and shape the amplified signal into a square wave signal, and the clamping circuit 220 is used to process the square wave signal and send it to the main control module 130.

[0031] In this embodiment, refer to Figure 6 The alarm module 140 includes an alarm switch circuit connected to the main control module 130 and an alarm control light box connected to the alarm switch circuit. The alarm switch circuit includes a relay, a diode and an inductor. The alarm switch circuit is used to receive the output level of the main control module 130; when the clamping circuit 220 clamps the level of the square wave signal to the input range of the main control module 130, the main control module 130 performs calculation processing on the speed acquisition signal corresponding to the input frequency signal to obtain a corresponding speed input signal; the main control module 130 performs judgment processing based on the speed input signal and the mode judgment signal to obtain an output level, and the main control module 130 controls the on and off of the alarm control light box through the alarm switch circuit based on the output level, wherein the mode judgment signal includes fixed-wing mode judgment, helicopter and transition mode judgment. The mode judgment signal input module 150 includes an RS422 communication circuit connected to the main control module 130. The RS422 communication circuit is used to transmit the speed value processed by the main control module 130 to the motor management system, and send the mode judgment signal of the motor management system to the main control module 130; the electromechanical management system can store and manage the speed, frequency, etc. of the engine, motor, etc., and the alarm control light box can include a buzzer, an indicator light, etc.

[0032] It should be noted that the main control module 130 controls the detection module 120 to detect the connection status between the rotor speed magnetic sensor and the rotor speed signal processor, including: the main control module 130 sends a power-on self-test instruction to the detection module 120, and the detection module 120 detects whether there is a signal input to the input interface of the rotor speed magnetic sensor; if there is no signal input, the main control module 130 sets the input frequency self-test signal to control the rotor speed magnetic sensor to connect to the speed measurement channel, and the main control module 130 receives the speed acquisition signal of the speed measurement channel for calculation and determines whether the speed measurement channel is normal, wherein each rotor speed magnetic sensor includes one speed measurement channel; if normal, the main control module 130 selects the capture frequency corresponding to the speed acquisition signal according to the lowest measurement frequency of the rotor speed magnetic sensor, wherein the capture frequency determines the frequency signal change rate according to the engine speed change rate and is calculated using a threshold comparison algorithm and a speed gradient prediction algorithm.

[0033] The detection module 120 is further configured to detect the input level of the AD interface of the main control module 130 to determine whether the working power supply of the main control module 130 is normal; If normal, the detection module 120 is further configured to detect the received data and the sent data of the communication interface of the main control module 130 and compare them to determine whether the communication interface of the main control module 130 is normal.

[0034] Specifically, the main control module 130 can be a microprocessor (MCU), and the processing circuit board 40 is mainly composed of a disconnection detection circuit (not shown), a self-test signal switching circuit 190, a port protection circuit, a filter circuit 200, an amplifier circuit 210, a clamping circuit 220, a microprocessor (main control module 130), an alarm switch circuit, a mode judgment signal input module 150 (which can be implemented through an RS422 communication circuit), etc. The self-test signal switching circuit 190 is mainly used for product power-on BIT test (built-in self-test). After the product is powered on, under the condition that there is no speed signal input, the power-on self-test program is started, and the microprocessor sends a control signal to change the level signal (The high-level signal output by the MCU's IO port) is connected to the connection circuit between the sensor (rotor speed magnetic sensor) and the product. By detecting its level signal, it is detected whether the connection between the product (rotor speed signal processor) and the sensor is broken. At the same time, the standard frequency signal (PWM signal) is connected to the speed measurement circuit (channel) of the product. The collected signal is compared with the standard signal (PWM signal) to determine whether the product's speed collection channel (one rotor speed magnetic sensor has only one speed collection channel) is working normally. The detection information is sent to the electromechanical management system through the communication interface circuit (port protection circuit and RS422 communication circuit).

[0035] The detection information mentioned above primarily includes information about the functioning of the speed acquisition channel, the acquisition signal from the speed acquisition channel, and the sensor connection. The port protection circuit provides impedance matching with the rotor speed magnetic sensor and protects against external impact, without affecting the sensor's output signal amplitude. The port protection circuit and the communication port protection circuit establish communication connections between various circuits or hardware modules. The input signal passes through a low-pass filter circuit (filter circuit), which effectively filters out high-frequency interference signals. The signal then passes through amplifier circuit 210, where it is appropriately amplified and shaped into a square wave signal for subsequent circuit processing. The voltage of the square wave signal (the processed rotor speed magnetic sensor signal) is then controlled within the acceptable range for the microprocessor by clamping circuit 220 for amplitude limiting protection.

[0036] Specifically, filter circuit 200 (low-pass filter) primarily filters the input frequency signal (the signal fed back from the self-test signal switching circuit), thereby suppressing high- and low-frequency interference in the input signal. Clamp circuit 220 primarily clamps the square wave signal to within the microprocessor input range. The microprocessor performs computations on the conditioned speed signal (according to the input mode judgment signal) and, based on the input mode judgment signal and the speed input signal conversion value, controls the alarm switch circuit to issue either a high speed alarm or a low speed alarm. The alarm switch circuit (low speed alarm output and high speed alarm output) primarily consists of a relay, a diode, and an inductor. It conducts upon receiving a high level from the microprocessor and outputs a low level, signaling an alarm. It disconnects upon receiving a low level signal and outputs a high level. Mode judgment signal input module 150 (circuit) primarily receives and level-converts mode judgment signals ("fixed-wing mode judgment" and "helicopter and transition mode judgment") for easy reading by the microprocessor interface. The communication circuit is composed of RS422 communication circuit, which is mainly used to transmit the speed value processed by the microprocessor to the electromechanical management system, and receive the mode judgment signal to the microprocessor of the product.

[0037] In a feasible embodiment, the rotor speed signal processor requires software design. The software design includes error prevention, reliability, and high security. The software program is stored in the memory of the microprocessor and can automatically run when powered on. It mainly performs power-on self-test, signal acquisition, communication interface, measurement channel switching, fault detection, digital output, and periodic self-test functions. The specific execution process is as follows: S1: During the power-on self-test process, the sensor disconnection test is used to determine whether the sensor is connected. Check whether there is a signal connected to the sensor input interface. If there is no signal connected, set the input frequency self-test signal to connect to the measurement channel (speed measurement channel), calculate the measurement data (speed signal), and determine whether the measurement channel is normal. S2: Determine the minimum measurement frequency based on the sensor's synchronization characteristics (the software program specifies that a frequency value of 0 corresponds to a speed below 6%, which is the minimum measurement frequency). Select an appropriate capture frequency (the capture frequency is the minimum measurement frequency × 0xFFFF) to improve algorithm efficiency. Determine the frequency signal change rate (for example, 20% rpm / s) based on the engine speed change rate to eliminate signal jitter. Select an appropriate filtering algorithm (threshold comparison algorithm combined with speed gradient prediction) based on the input signal frequency value to ensure real-time output data. S3: During the periodic self-test process, the input level of the AD interface (analog-to-digital conversion) of the microprocessor (MCU) is detected in real time to determine whether the working power supply (±15V, 5V) is normal; the received data and the sent data of the communication interface (circuit) are compared to determine whether the communication interface is normal; S4: In order to prevent the software from running away, the software sets an on-chip watchdog (circuit) and the watchdog reset is set to 1s so that the software can be reliably reset after running away.

[0038] In this embodiment, the bottom layer is initialized, the sensor coil receives the self-test instruction, and the measurement channel executes the self-test instruction. After the self-test sensor is working normally, the speed measurement channel needs to be tested (speed measurement, converted into digital signal output) to determine whether the speed change rate is higher than 102%; If so, the output speed high alarm is triggered; If not, it is determined whether the input mode judgment signal is a fixed-wing mode; If in fixed-wing mode, determine whether the current speed change rate is less than 83%; If so, the output speed is low alarm (alarm); If not, return to continue speed measurement; If it is not in fixed-wing mode, determine whether the current speed change rate is less than 96%; If so, the output speed is low alarm (alarm); If not, return to continue speed measurement.

[0039] Among them, digital information (signals) are periodically sent to the electromechanical management system, and after the power outage is over, digital information is periodically sent to the alarm system. The rotor speed signal processor provided by the present invention adopts dual judgment of rotor speed qualification in helicopter mode and fixed-wing mode, integrates high-precision timer and hardware CRC check unit, which can shorten the response time and adopts threshold comparison algorithm ( Figure 7The signal processing algorithm combines the comparison and judgment of the three speed constants in the speed gradient prediction (the interval value of the three speed constants) with the speed signal protection and improved processor reliability. It solves the dual judgment of the rotor speed in helicopter mode and fixed-wing mode from the source, and the high precision and anti-EMI problem of frequency and voltage conversion in dual modes, which facilitates the balance between data real-time performance and ensuring the realization of functional safety integrity.

[0040] In all examples shown and described herein, any specific values ​​should be interpreted as merely exemplary and not limiting, and thus other examples of the exemplary embodiments may have different values.

[0041] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0042] The above-described embodiments merely illustrate several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that variations and modifications are possible without departing from the scope of the present invention, and such variations and modifications are fully within the scope of protection of the present invention.

Claims

1. A rotor speed signal processor with dual-mode criterion, characterized in that: The rotor speed signal processor includes a housing, a power circuit board disposed at the bottom of the housing, an inter-board connector disposed on the power circuit board, and a processing circuit board located on the inter-board connector. An electrical connector for connecting a plurality of rotor speed magnetic sensors is disposed on the side of the housing. The power circuit board includes a power module and a voltage adjustment module. The power module includes a rectifier unit connected to a power input end, a first energy storage unit, a first filter unit, and a second energy storage unit. The first energy storage unit and the first filter unit are both connected to the rectifier unit. The first filter unit is connected to one end of the second energy storage unit, and the other end of the second energy storage unit is connected to the voltage adjustment module. The processing circuit board includes a detection module connected to the plurality of rotor speed magnetic sensors, a main control module connected to the detection module, an alarm module, and a mode judgment signal input module. The voltage adjustment module, the alarm module, and the mode judgment signal input module are all connected to the main control module. The mode judgment signal input module is used to connect to the motor management system and receive the mode judgment signal of the motor management system. Among them, the power supply module and the voltage adjustment module are used to supply power to the main control module, the main control module controls the detection module to detect the connection status of the rotor speed magnetic sensor and the rotor speed signal processor, and receives the speed acquisition signal and the mode judgment signal of the rotor speed magnetic sensor according to the connection status, the main control module processes the speed acquisition signal and the mode judgment signal and controls the on and off of the alarm module.

2. The rotor speed signal processor with dual-mode criterion according to claim 1, characterized in that: The voltage adjustment module includes a DCDC converter connected to the second energy storage unit, a second filtering unit and a low voltage difference three-terminal voltage regulator, one end of the second filtering unit is connected to the DCDC converter, and the other end of the second filtering unit is connected to the low voltage difference three-terminal voltage regulator, and the low voltage difference three-terminal voltage regulator is connected to the main control module.

3. The rotor speed signal processor with dual-mode criterion according to claim 2, characterized in that: The rectifier unit includes a diode D19, the first energy storage unit includes a capacitor C48, the first filtering unit includes a common-mode suppression inductor T1, a capacitor C36, a capacitor C37 and a filter IC11, the anode of the diode D19 is used to connect to the power input terminal, the cathode of the diode D19 is connected to the capacitor C48 and one end of the common-mode suppression inductor T1, the other end of the common-mode suppression inductor T1 is connected to the capacitor C36 and the capacitor C37 respectively, and the capacitor C36 and the capacitor C37 are both connected to the filter IC11; The second energy storage unit includes capacitor C38, capacitor C39, capacitor C40, diode D20, diode D21 and resistor R38, the anode of diode D20, capacitor C38 and capacitor C39 are all connected to filter IC11, and the cathode of diode D21 is connected to resistor R38, capacitor C40 and cathode of diode D21; The DCDC converter includes a chip IC10, the second filtering unit includes a capacitor C41, a capacitor C42, a capacitor C43, a capacitor C44, a capacitor C45, a capacitor C46 and a capacitor C47, capacitor C41 and capacitor C42 are connected in parallel, capacitor C43 and capacitor C44 are connected in parallel, capacitor C46 and capacitor C47 are connected in parallel to chip IC10 and are respectively connected to chip IC10, the low voltage difference three-terminal voltage regulator includes a chip IC12, a capacitor C49, a capacitor C50, a capacitor C51 and a capacitor C52, capacitor C49, capacitor C50, capacitor C51 and capacitor C52 are connected in parallel to chip IC12.

4. The rotor speed signal processor with dual-mode criterion according to claim 3, characterized in that: The first energy storage unit and the second energy storage unit both use high-energy tantalum capacitors, and the capacitance values ​​of capacitors C41, C43 and C46 are greater than the capacitance values ​​of capacitors C36, C37, C39, C40, C42, C44, C45 and C47.

5. The rotor speed signal processor with dual-mode criterion according to claim 1, characterized in that: The detection module includes a self-test signal switching circuit connected to the rotor speed magnetic sensor and a filter circuit, an amplifier circuit and a clamping circuit connected in sequence, and the filter circuit and the main control module are both connected to the self-test signal switching circuit; The self-test signal switching circuit is used to perform a power-on BIT test on the rotor speed magnetic sensor, the filtering circuit is used to filter the input frequency signal of the self-test signal switching circuit, the amplifying circuit is used to amplify the filtered signal and shape the amplified signal into a square wave signal, and the clamping circuit is used to process the square wave signal and send it to the main control module.

6. The rotor speed signal processor with dual-mode criterion according to claim 5, characterized in that: The alarm module includes an alarm switch circuit connected to the main control module and an alarm control light box connected to the alarm switch circuit. The alarm switch circuit includes a relay, a diode and an inductor. The alarm switch circuit is used to receive the output level of the main control module. When the clamping circuit clamps the level of the square wave signal to the input range of the main control module, the main control module performs calculation processing on the speed acquisition signal corresponding to the input frequency signal to obtain a corresponding speed input signal; The main control module performs judgment and processing based on the speed input signal and the mode criterion signal to obtain an output level. The main control module controls the on and off of the alarm control light box through the alarm switch circuit based on the output level, wherein the mode criterion signal includes fixed-wing mode judgment, helicopter and transition mode judgment.

7. The rotor speed signal processor with dual-mode criterion according to claim 6, characterized in that: The mode judgment signal input module includes an RS422 communication circuit connected to the main control module, and the RS422 communication circuit is used to transmit the speed value processed by the main control module to the motor management system, and send the mode judgment signal of the motor management system to the main control module.

8. The rotor speed signal processor with dual-mode criterion according to claim 1, characterized in that: The main control module controls the detection module to detect the connection status between the rotor speed magnetic sensor and the rotor speed signal processor, including: The main control module sends a power-on self-test instruction to the detection module, and the detection module detects whether there is a signal input from the input interface of the rotor speed magnetic sensor; If there is no signal input, the main control module sets an input frequency self-test signal to control the rotor speed magnetic sensor to connect to the speed measurement channel, and the main control module receives the speed acquisition signal of the speed measurement channel to perform a calculation and determine whether the speed measurement channel is normal, wherein each rotor speed magnetic sensor includes one speed measurement channel; If normal, the main control module selects the capture frequency corresponding to the speed acquisition signal according to the lowest measurement frequency of the rotor speed magnetic sensor, wherein the capture frequency determines the frequency signal change rate according to the engine speed change rate and is calculated using a threshold comparison algorithm and a speed gradient prediction algorithm.

9. The rotor speed signal processor with dual-mode criterion according to claim 8, characterized in that: Also includes: The detection module is also used to detect the input level of the AD interface of the main control module to determine whether the working power supply of the main control module is normal; If normal, the detection module is further configured to detect the received data and the sent data of the communication interface of the main control module and compare them to determine whether the communication interface of the main control module is normal.

10. The rotor speed signal processor with dual-mode criterion according to claim 1, characterized in that: The rotor speed signal processor also includes a cover plate and a limit assembly arranged on the shell, and the limit assembly includes a flat washer arranged on the side of the shell, a spring washer and a pan head screw attached to the flat washer, one end of the pan head screw is connected to the electrical connector, and the other end of the pan head screw is used to fix the spring washer and the flat washer.

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