Adjustment method of braking torque of carbon ceramic brake disc

Abstract

The present invention proposes a method for adjusting the braking torque of a carbon-ceramic brake disc, comprising: dividing a speed range into n intervals, dividing the maximum speed REFSpeed_max into n intervals with a speed of b, and establishing an array CmdTable[n]; assigning values ​​to the array CmdTable[n], assigning a minimum anti-skid current to each speed segment in the array CmdTable[n] to limit the maximum braking pressure of each speed segment, wherein the minimum anti-skid current assigned to each speed segment is adjusted in subsequent simulation debugging and power bench joint testing; reading the anti-skid current value corresponding to each speed; and outputting the maximum braking current value. The adjustment method avoids a sudden change in the deceleration rate of the brake system in the low-speed stage, and at the same time adjusts the corresponding pressure according to the characteristics of the carbon-ceramic brake disc in each speed segment, thereby avoiding the pitching phenomenon in the low-speed segment that may occur when using the carbon-ceramic brake disc while ensuring the stability of the brake pressure and having better braking quality.

Description

Technical Field

[0001] The present invention relates to the technical field of brake disc pressure regulation, and in particular to a method for regulating the braking torque of a carbon-ceramic brake disc. Background Art

[0002] Existing aircraft braking technology does not address the high torque characteristics of ceramic brake discs at low speeds during aircraft landing and braking. Carbon ceramic brake discs often slip frequently at low speeds during aircraft braking, and may even cause the aircraft to shake and dive.

[0003] For example, the patent application document with Chinese invention patent application number CN202210703341.X discloses a closed-loop model predictive control method for an aircraft anti-skid braking system. First, an overall model of the all-electric anti-skid braking system is established, the all-electric anti-skid braking system is transformed in coordinates, and feedback linearization processing is performed to obtain a linear standard system; the system parameter changes and unmodeled dynamics are attributed to the system lumped disturbance terms to form an extended system; a finite-time observer is designed to perform online estimation of the system state quantities and lumped disturbances; the objective function of the anti-skid braking control system is constructed; the system state quantities of the anti-skid braking control system in the prediction time domain are predicted; based on the reference value of the slip rate and the disturbance observation value, the reference value of the control sequence in the prediction time domain is solved; the objective function is minimized, and the optimal control gain corresponding to the state feedback controller is obtained based on the analytical solution of the objective function.

[0004] The existing technology still has not made any improvements to the high torque characteristic of the brake disc at low speeds, and problems such as slipping and aircraft shaking still exist at low speeds.

[0005] Based on the above-mentioned technical problems existing in the prior art, the present invention provides a method for adjusting the braking torque of a carbon-ceramic brake disc. Summary of the Invention

[0006] The present invention provides a method for adjusting the braking torque of a carbon-ceramic brake disc.

[0007] The present invention adopts the following technical solutions:

[0008] A method for adjusting the braking torque of a carbon-ceramic brake disc, comprising:

[0009] Step 1: Divide the speed range into n intervals, amplify the speed value by 10,000 times and the anti-skid current value by 100 times for calculation, divide the maximum speed REFSpeed_max into n intervals of b speed, and create an array CmdTable[n], then:

[0010] If REFSpeed_max / b cannot be divided evenly,

[0011] n=(REFspeed_max / b)+1……(1),

[0012] If REFSpeed_max / b is divisible,

[0013] n=REFspeed_max / b......(2),

[0014] In the above formula 1-2, if b = 100000, it means that the maximum speed is divided into 10 km speed segments; REFSpeed_max is the maximum reference speed of the aircraft;

[0015] Step 2: Assign values ​​to the array CmdTable[n] and assign a minimum anti-skid current to each speed segment in the array CmdTable[n] to limit the maximum brake pressure of each speed segment. The minimum anti-skid current assigned to each speed segment will be adjusted in subsequent simulation debugging and power bench joint test to achieve a stable brake disc throughout the entire braking process.

[0016] Step 3: Read the anti-skid current value corresponding to each speed:

[0017]

[0018] In the above formula, SpeedLever represents the interval number corresponding to the speed;

[0019] Perform linear processing on the anti-skid current in each speed range to prevent step-by-step changes in the anti-skid current, which may cause a jerking feeling when braking.

[0020] Step 4: Output the maximum braking current value:

[0021] ComputeCurrentmax=BRKCMDMax-BRKCOMD......(4);

[0022] In the above formula, ComputeCurrentMin is the maximum brake current value output, BRKCMDMax is the maximum brake current of the brake command sensor, and BRKCOMD is the minimum anti-skid current value corresponding to each speed.

[0023] Furthermore, in step 3, when CmdTable[SpeedLever]<CmdTable[SpeedLever+1]: BRKCOMD=CmdTable[SpeedLever]+(((REFSpeed-SpeedLever*b) / (b / 100))*(CmdTable[Speed ​​Lever+1]-CmdTable[SpeedLever])) / 100……(5).

[0024] Furthermore, in step 3, when CmdTable[SpeedLever]≥CmdTable[SpeedLever+1]: BRKCOMD=CmdTable[SpeedLever]-(((REFSpeed-SpeedLever*b) / (b / 100))*(CmdTable[Speed ​​Lever]-CmdTable[SpeedLever+1])) / 100……(6).

[0025] Furthermore, in step 1, the control accuracy information of the brake disc braking torque is obtained, and the control accuracy is positively correlated with the number of speed segments.

[0026] Furthermore, in step 2, a minimum anti-skid current is assigned to each speed segment to limit the maximum brake pressure; and parameters are adjusted based on the joint test with the entire brake system to determine the size of the minimum anti-skid current corresponding to each speed range.

[0027] Compared with the prior art, the present invention has the following advantages:

[0028] The method for adjusting the braking torque of the carbon-ceramic brake disc described in the present invention carries out targeted processing on the control algorithm, avoiding the sudden change of the deceleration rate of the brake system in the low-speed stage. At the same time, the corresponding pressure is adjusted according to the characteristics of the carbon-ceramic brake disc in each speed segment. While avoiding the pitching phenomenon in the low-speed segment that may occur when using the carbon-ceramic brake disc, the braking pressure is ensured to be stable, thereby achieving better braking quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram of the corresponding relationship between the normal full-load reference speed and the maximum braking current in an embodiment of the present invention;

[0030] Figure 2 Schematic diagram of the maximum braking torque at various speeds in a normal full-load braking test under full braking command in an embodiment of the present invention;

[0031] Figure 3 This is a schematic diagram of the maximum braking torque at various speeds in a normal full-load braking test using the traditional method with full braking command. DETAILED DESCRIPTION

[0032] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other unless there is a conflict.

[0033] Example

[0034] The method for adjusting the braking torque of the carbon-ceramic brake disc comprises:

[0035] Step 1, divide the speed range into n intervals (for example, divide the entire process from 0 to the maximum speed, and divide the speed from 0 to 100 km / h into 10 intervals, then 10 kilometers is an interval. The carbon ceramic brake disc has a large torque difference in different speed intervals under the same braking pressure. The purpose of dividing the speed into n intervals is to adjust the pressure according to different speed segments). Amplify the speed value by 10000 times and the anti-skid current value by 100 times for calculation. Divide the maximum speed REFSpeed_max into n intervals with a speed of b. The intervals can be divided according to the control accuracy of the brake disc braking torque. If the control accuracy is high, the speed segments are divided into more intervals. For example, divide 100 km / h into 10 intervals, and perform pressure control on the braking torque corresponding to each 10 km / h. Divide it into 5 intervals, and perform pressure control on the braking torque corresponding to 20 km / h. Establish an array CmdTable[n], then:

[0036] If REFSpeed_max / b cannot be divided evenly,

[0037] n=(REFSpeed_max / b)+1,

[0038] If REFSpeed_max / b is divisible,

[0039] n=REFSpeed_max / b),

[0040] In the above formula, if b = 100000, it means that the maximum speed is divided into 10 km / h speed segments; REFSpeed_max is the maximum reference speed of the aircraft. For example, if the maximum reference speed REFSpeed_max is divided into 10 km / h intervals, assuming REFSpeed_max = 215 km / h, then b = 100000, and n = (REFSpeed_max / b) + 1 = (2150000 / 100000) + 1 = 22);

[0041] Step 2: Assign values ​​to the array CmdTable[n] and assign a minimum anti-skid current to each speed segment in the array CmdTable[n] to limit the maximum brake pressure of each speed segment. The minimum anti-skid current assigned to each speed segment will be adjusted in subsequent simulation debugging and power bench joint test to achieve a stable brake disc throughout the entire braking process.

[0042] Step 3: Read the anti-skid current value corresponding to each speed:

[0043]

[0044] In the above formula, SpeedLever represents the interval number corresponding to the speed;

[0045] When CmdTable[SpeedLever]<CmdTable[SpeedLever+1]:

[0046] BRKCOMD=CmdTable[SpeedLever]+(((REFSpeed-SpeedLever*b) / (b / 100))*(CmdTable[Speed

[0047] Lever+1]-CmdTable[SpeedLever])) / 100;

[0048] When CmdTable[SpeedLever]≥CmdTable[SpeedLever+1]:

[0049] BRKCOMD=CmdTable[SpeedLever]-(((REFSpeed-SpeedLever*b) / (b / 100))*(CmdTable[Speed

[0050] Lever]-CmdTable[SpeedLever+1])) / 100;

[0051] Perform linear processing on the anti-skid current in each speed range to prevent step-by-step changes in the anti-skid current, which may cause a jerking feeling when braking.

[0052] Step 4: Output the maximum braking current value:

[0053] ComputeCurrentmax=BRKCMDMax-BRKCOMD;

[0054] In the above formula, ComputeCurrentmax is the maximum brake current value output, and BRKCMDMax is the maximum brake current of the brake command sensor.

[0055] In step 1 of the above embodiment, the control accuracy information of the brake disc braking torque is obtained, and the control accuracy is positively correlated with the number of speed segments.

[0056] In step 2 of the above embodiment, a minimum anti-skid current is assigned to each speed segment based on the specific brake disc characteristics to limit the maximum brake pressure; then, parameters are adjusted based on the joint test with the entire brake system to determine the minimum anti-skid current corresponding to each speed range.

[0057] In order to verify the technical effect of the method for adjusting the braking torque of a carbon-ceramic brake disc described in this embodiment, a power station system joint test was conducted using the method in the hardware environment of a certain military aircraft model and compared with a traditional method. The test requirements and methods are shown in Table 1:

[0058] Table 1 Test requirements for electronic anti-skid brake system of a certain type of aircraft

[0059]

[0060] Judging from the test results, the overall braking torque is smoother. At the same time, under 1 / 2 load and 1 / 4 load, compared with the traditional method, this method has fewer slips and higher braking efficiency.

[0061] Under normal braking, full load, and full travel conditions, the anti-skid current and speed correspond to the method described in this embodiment. Figure 1 As shown, when there is no slipping, the anti-skid current outputs the corresponding anti-skid current according to the speed to adjust the pressure and make the braking torque stable. Below the anti-skid failure speed, no control is performed. The comparison of normal braking full load and full stroke braking torque before and after improvement is as follows: Figure 2-3 As shown in Table 2, the improvement of braking distance and deceleration rate by the method described in this embodiment compared with the traditional method is shown in Table 2:

[0062] Table 2 Improvements in braking distance and deceleration rate

[0063]

[0064] According to Table 2, it can be seen that the conventional method has convex braking torques in high-speed and low-speed sections; while the method described in this embodiment has a stable braking torque throughout the entire process above the anti-skid failure speed.

[0065] The present invention is not limited to the above-described embodiments. The above-described embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention. Such changes and modifications are intended to fall within the scope of the present invention. The scope of protection claimed in the present invention is defined by the appended claims.

Claims

1. A method for adjusting the braking torque of a carbon-ceramic brake disc, characterized in that: include: Step 1: Divide the speed range into n intervals, amplify the speed value by 10,000 times and the anti-skid current value by 100 times for calculation, divide the maximum speed REFSpeed_max into n intervals of b speed, and create an array CmdTable[n], then: If REFSpeed_max / b cannot be divided evenly, n=(REFspeed_max / b)+1……(1), If REFSpeed_max / b is divisible, n=REFspeed_max / b......(2), In the above formula 1-2, if b = 100000, it means that the maximum speed is divided into 10 km speed segments; REFSpeed_max is the maximum reference speed of the aircraft; Step 2: Assign values ​​to the array CmdTable[n] and assign a minimum anti-skid current to each speed segment in the array CmdTable[n] to limit the maximum brake pressure of each speed segment. The minimum anti-skid current assigned to each speed segment will be adjusted in subsequent simulation debugging and power bench joint test to achieve a stable brake disc throughout the entire braking process. Step 3: Read the anti-skid current value corresponding to each speed: In the above formula, SpeedLever represents the interval number corresponding to the speed; Perform linear processing on the anti-skid current in each speed range to prevent step-by-step changes in the anti-skid current, which may cause a jerking feeling when braking. When CmdTable[SpeedLever]<CmdTable[SpeedLever+1]: BRKCOMD=CmdTable[SpeedLever]+(((REFSpeed-SpeedLever*b) / (b / 100))*(CmdTable[SpeedLever+1]-CmdTable[SpeedLever])) / 100...(5); When CmdTable[SpeedLever]≥CmdTable[SpeedLever+1]: BRKCOMD=CmdTable[SpeedLever]-(((REFSpeed-SpeedLever*b) / (b / 100))*(CmdTable[Sp eedLever]-CmdTable[SpeedLever+1])) / 100...(6); Step 4: Output the maximum braking current value: ComputeCurrentmax=BRKCMDMax-BRKCOMD……(4); In the above formula, ComputeCurrentmax is the maximum brake current output value, BRKCMDMax is the maximum brake current of the brake command sensor, and BRKCOMD is the minimum anti-skid current corresponding to each speed.

2. The method for adjusting the braking torque of a carbon-ceramic brake disc according to claim 1, characterized in that: In step 1, the control accuracy information of the brake disc braking torque is obtained. The control accuracy is positively correlated with the number of speed segments.

3. The method for adjusting the braking torque of a carbon-ceramic brake disc according to claim 1, characterized in that: In step 2, the minimum anti-skid current is assigned to each speed segment to limit the maximum brake pressure; then, parameters are adjusted based on the joint test with the entire brake system to determine the minimum anti-skid current corresponding to each speed range.

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