Drum load intensifier and method for testing heavy vehicle by using light drum

Abstract

The invention discloses a drum load intensifier and a method for testing a heavy vehicle by using a light drum, and belongs to the technical field of vehicle testing. The method comprises the following steps: determining the angle of the air butterfly valve; the drum load intensifier is installed on a hub fixing bolt of a vehicle driving wheel; a centrifugal blower is fixed on the ground of the light rotary drum; an output signal of the load control and signal processor is connected with a control computer of the light drum; the air butterfly valve is adjusted to the determined opening degree and fixed; calculating the actual whole vehicle power; and carrying out a corresponding whole vehicle test on the light rotary drum. Through cooperative control architecture design of the drum load intensifier and the light drum, power limitation of traditional light dynamometer equipment is broken through, and an existing light drum system has the capacity of being compatible with high-power and heavy vehicle testing.

Description

Technical Field

[0001] The invention relates to a drum load intensifier and a method for testing a heavy vehicle using a light drum, belonging to the technical field of vehicle testing. Background Art

[0002] During the automotive R&D process, lightweight drums serve as key testing equipment, undertaking the important task of verifying the performance of the vehicle's powertrain. Currently, lightweight drums face the following challenges when testing high-power and heavy vehicles:

[0003] On the one hand, the design parameters of existing light-duty drums (such as maximum absorbed power and torque capacity) can no longer meet the testing requirements of modern electric vehicles and heavy-duty commercial vehicles; on the other hand, the dynamic response characteristics of existing light-duty drums make it difficult to accurately simulate the extreme operating conditions of high-power vehicles.

[0004] The above technical bottlenecks directly lead to the following problems during the testing process:

[0005] 1. Insufficient testing capabilities: The power / torque curve of the vehicle under test cannot be fully covered, and approximate testing can only be performed by reducing operating conditions or numerical simulation, which seriously affects data accuracy;

[0006] 2. High cost of equipment upgrade: Replacing high-power drums and supporting systems requires huge investment, which puts a heavy burden on enterprises in the context of economic downturn;

[0007] 3. Serious waste of resources: A large number of light drums that are still in service are facing early elimination due to backward technical indicators. Summary of the Invention

[0008] In order to solve the problems existing in the background technology, the present invention provides a drum load intensifier and a method for testing heavy vehicles using a light drum.

[0009] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: a drum load intensifier, including a centrifugal blower, an air butterfly valve, a pressure differential sensor, and a load control and signal processor; the air inlet end of the centrifugal blower is installed with an air butterfly valve, and the air outlet end of the centrifugal blower is installed with a pressure differential sensor, and the air butterfly valve and the pressure differential sensor are both connected to the load control and signal processor for signal transmission.

[0010] A method for testing a heavy vehicle using a light drum according to the present invention comprises the following steps:

[0011] S1: Determine the angle of the air butterfly valve of the drum load intensifier;

[0012] S101: Calculate the difference power using the vehicle's rated power and the light drum's maximum power;

[0013] S102: The maximum load power is compared with the differential power to determine the angle of the butterfly valve.

[0014] The process of determining the maximum load power in S102 is as follows:

[0015] S10201: Mechanically connect the drum load intensifier to the motor of the vehicle under test to form a power transmission path;

[0016] S10202: Set the motor speed test range from 0 rpm to 1000 rpm, divide the speed operating points into steps of 100 rpm, and simultaneously set the air butterfly valve opening from the initial value of 50% to divide the load operating points into steps of 5%, thereby constructing a two-dimensional speed-load operating matrix.

[0017] S10203: Acquire input voltage and current parameters of the motor in real time through the voltage acquisition module and the current acquisition module;

[0018] S10204: Calculate the motor power under the current working condition, i.e., the equivalent load power of the drum load intensifier, and establish a stable aerodynamic resistance load under the working condition by maintaining a constant opening of the air butterfly valve;

[0019] S10206: Use a differential pressure sensor to measure the wind speed at the air outlet of the drum load intensifier to obtain the air flow velocity parameters corresponding to each operating point;

[0020] S10207: Establish a mapping relationship between motor power and outlet wind speed, and use the least squares method to perform quadratic polynomial fitting on the test data to obtain the power-wind speed characteristic equation:

[0021] Where:

[0022] Indicates the voltage of the motor under each working condition;

[0023] Indicates the current of the motor under each working condition;

[0024] Indicates the speed of the motor;

[0025] Indicates the output shaft radius of the motor;

[0026] Indicates the wind speed measured by the differential pressure sensor;

[0027] represents the fixed drag coefficient of the drum load intensifier;

[0028] Indicates the sliding resistance coefficient of the drum load intensifier;

[0029] Indicates the air resistance coefficient of the drum load intensifier;

[0030] S10207 coefficients ,coefficient and coefficients The determination process is as follows:

[0031] S1020701: After the air butterfly valve is fixed at a specific opening, the motor is started and the wind speed is measured at the same time;

[0032] S1020702: Increase the motor current to a specific wind speed, measure the motor power at that time, and calculate the impeller thrust at that time ;

[0033] S1020703: Set the wind speed to 10km / h as the step size, and then decrease the wind speed step size one by one. Measure the motor power at this wind speed and calculate the impeller thrust at this wind speed. , we get the quadratic function with the vertical axis being the impeller thrust and the horizontal axis being the wind speed:

[0034] S1020704: Obtain coefficients based on quadratic functions ,coefficient and coefficients ;

[0035] S1020705: Calculate the coefficients of all openings of the air butterfly valve in sequence ,coefficient and coefficients .

[0036] S2: Install the drum load intensifier on the wheel hub fixing bolts of the vehicle's driving wheel through the wheel mounting hole;

[0037] S3: Fix the centrifugal blower of the drum load intensifier on the ground of the light drum to ensure that the drum load intensifier does not rotate with the driving wheel when the vehicle driving wheel rotates;

[0038] S4: Connect the output signal of the load control and signal processor of the drum load intensifier to the control computer of the light drum;

[0039] S5: Adjust the air butterfly valve of the drum load intensifier to the fixed opening angle determined in S1 and fix it;

[0040] S6: Calculate the actual vehicle power;

[0041] S7: Perform corresponding vehicle tests on a light drum.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] This invention overcomes the power limitations of traditional lightweight dynamometers through the collaborative control architecture design of a drum load intensifier and a lightweight drum, enabling existing lightweight drum systems to be compatible with both high-power and heavy-duty vehicle testing. By employing an aerodynamic drag compensation mechanism and a modular mounting structure, full coverage of the dynamic characteristics of the vehicle under test can be achieved by dynamically adjusting the opening of the drum load intensifier's air butterfly valve, without requiring modification to the main structure of the lightweight drum. This avoids the need for high-cost equipment replacement, extends the service life of existing test resources, and reduces the complexity of test system upgrades through vehicle-side minimization reforms, providing a testing solution for vehicle powertrain development that is both economical and technically feasible. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a structural schematic diagram of the drum load intensifier of the present invention. DETAILED DESCRIPTION

[0045] The technical solutions of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0046] A drum load intensifier includes a centrifugal blower 1, an air butterfly valve 3, a pressure differential sensor 5 and a load control and signal processor 6; the air inlet end 2 of the centrifugal blower 1 is installed with the air butterfly valve 3, and the air outlet end 4 of the centrifugal blower 1 is installed with the pressure differential sensor 5, and the air butterfly valve 3 and the pressure differential sensor 5 are both connected to the load control and signal processor 6 for signal transmission.

[0047] The drum load intensifier utilizes the principle of a turbo blower. An electrically controlled air butterfly valve 3 controls the air volume at the intake port 2, thereby providing a load to the internal centrifugal blower 1. A differential pressure sensor 5 also measures the outlet wind speed. Different resistance loads are generated based on different rotational speeds and wind speeds, thereby increasing the vehicle's load.

[0048] A method for testing a heavy vehicle using a light drum according to the present invention comprises the following steps:

[0049] S1: Determine the angle of the air butterfly valve 3 of the drum load intensifier;

[0050] S101: Calculate the difference power using the vehicle's rated power and the light drum's maximum power;

[0051] S102: The maximum load power is compared with the differential power to determine the angle of the butterfly valve.

[0052] The process of determining the maximum load power in S102 is as follows:

[0053] S10201: Mechanically connect the drum load intensifier to the motor of the vehicle under test to form a power transmission path;

[0054] S10202: Set the motor speed test range from 0 rpm to 1000 rpm, divide the speed operating points into steps of 100 rpm, and simultaneously set the opening of air butterfly valve 3 from an initial value of 50% to divide the load operating points into steps of 5%, thereby constructing a two-dimensional speed-load operating matrix.

[0055] S10203: Acquire input voltage and current parameters of the motor in real time through the voltage acquisition module and the current acquisition module;

[0056] S10204: Calculate the motor power under the current working condition based on the motor power conversion efficiency formula, i.e., the equivalent load power of the drum load intensifier, and establish a stable aerodynamic resistance load under this working condition by maintaining a constant opening of the air butterfly valve 3;

[0057] S10206: Use a differential pressure sensor to measure the wind speed at the air outlet of the drum load intensifier to obtain the air flow velocity parameters corresponding to each operating point;

[0058] S10207: Establish a mapping relationship between motor power and outlet wind speed, and use the least squares method to perform quadratic polynomial fitting on the test data to obtain the power-wind speed characteristic equation:

[0059] Where:

[0060] Indicates the voltage of the motor under each working condition, unit is V;

[0061] Indicates the current of the motor under each working condition, unit is A;

[0062] Indicates the speed of the motor, in rpm;

[0063] Indicates the output shaft radius of the motor, in m;

[0064] Indicates the wind speed measured by the differential pressure sensor, in km / h;

[0065] represents the fixed drag coefficient of the drum load intensifier;

[0066] Indicates the sliding resistance coefficient of the drum load intensifier;

[0067] Indicates the air resistance coefficient of the drum load intensifier;

[0068] S10207 coefficients ,coefficient and coefficients The determination process is as follows:

[0069] S1020701: After the air butterfly valve (3) is fixed at a specific opening (e.g. 10% opening), the motor is started and the wind speed is measured at the same time;

[0070] S1020702: Increase the motor current to reach a specific wind speed (e.g. ) and then measure the motor power at this time and calculate the impeller thrust at this time ;

[0071] S1020703: Set the wind speed to 10km / h as the step size, and then decrease the wind speed step size one by one. Measure the motor power at this wind speed and calculate the impeller thrust at this wind speed. , we get the quadratic function with the vertical axis being the impeller thrust and the horizontal axis being the wind speed:

[0072] S1020704: Obtain coefficients based on quadratic functions ,coefficient and coefficients ;

[0073] S1020705: Calculate the coefficients of the air butterfly valve (3) at all openings ,coefficient and coefficients .

[0074] S2: Install the drum load intensifier on the wheel hub fixing bolts of the vehicle driving wheel through the wheel mounting hole 7;

[0075] When high-power vehicles (such as hybrid and electric light passenger cars and special high-torque heavy trucks) are tested on a light drum, the peak torque may exceed the drum limit and the steady-state power may exceed the maximum power that the drum can withstand, which may cause serious faults such as runaway and speeding.

[0076] The present invention installs a drum load intensifier on the driving wheel of the test vehicle to assist the light drum in providing the whole vehicle load, thereby achieving effective load control of the vehicle, thereby realizing the effective load test of the above vehicle on the light drum.

[0077] S3: Fix the centrifugal blower 1 of the drum load intensifier on the ground of the light drum to ensure that when the vehicle driving wheel rotates, the drum load intensifier does not rotate with the driving wheel;

[0078] S4: connecting the output signal of the load control and signal processor 6 of the drum load intensifier to the control computer of the light drum;

[0079] S5: Adjust the air butterfly valve 3 of the drum load intensifier to the fixed opening angle determined in S1 and fix it;

[0080] S6: Superimpose the maximum load power and the actual power of the light drum to calculate the actual vehicle power;

[0081] S7: Perform corresponding vehicle tests on a light drum.

[0082] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

[0083] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A drum load intensifier, characterized by: The invention comprises a centrifugal blower (1), an air butterfly valve (3), a pressure difference sensor (5), and a load control and signal processor (6); the air inlet end (2) of the centrifugal blower (1) is equipped with the air butterfly valve (3), the air outlet end (4) of the centrifugal blower (1) is equipped with the pressure difference sensor (5), and the air butterfly valve (3) and the pressure difference sensor (5) are both connected to the load control and signal processor (6) for signal transmission.

2. A method for testing heavy vehicles using a light drum, characterized in that: The method comprises the following steps: S1: Determine the angle of the air butterfly valve (3) of the drum load intensifier; S2: Install the drum load intensifier on the wheel hub fixing bolts of the vehicle driving wheel through the wheel mounting hole (7); S3: Fix the centrifugal blower (1) of the drum load intensifier on the ground of the light drum to ensure that when the vehicle driving wheel rotates, the drum load intensifier does not rotate with the driving wheel; S4: connecting the output signal of the load control and signal processor (6) of the drum load intensifier to the control computer of the light drum; S5: Adjust the air butterfly valve (3) of the drum load intensifier to the fixed opening angle determined in S1 and fix it; S6: Calculate the actual vehicle power; S7: Perform corresponding vehicle tests on a light drum.

3. The method of using a light drum to test a heavy vehicle according to claim 2, characterized in that: The S1 comprises the following steps: S101: Calculate the difference power using the vehicle's rated power and the light drum's maximum power; S102: The maximum load power is compared with the differential power to determine the angle of the butterfly valve.

4. A method for testing heavy vehicles using a light drum according to claim 3, characterized in that: The process of determining the maximum load power in S102 is as follows: S10201: Mechanically connect the drum load intensifier to the motor of the vehicle under test to form a power transmission path; S10202: Set the motor speed test range from 0 rpm to 1000 rpm, divide the speed working point into steps of 100 rpm, and simultaneously set the opening of the air butterfly valve (3) from the initial value of 50% to divide the load working point into steps of 5%, and construct a speed-load two-dimensional working condition matrix; S10203: Acquire input voltage and current parameters of the motor in real time through the voltage acquisition module and the current acquisition module; S10204: Calculate the motor power of the current working condition, i.e., the equivalent load power of the drum load intensifier, and establish a stable aerodynamic resistance load under this working condition by maintaining a constant opening of the air butterfly valve (3); S10206: Use a differential pressure sensor to measure the wind speed at the air outlet of the drum load intensifier to obtain the air flow velocity parameters corresponding to each operating point; S10207: Establish a mapping relationship between motor power and outlet wind speed, and use the least squares method to perform quadratic polynomial fitting on the test data to obtain the power-wind speed characteristic equation: Where: Indicates the voltage of the motor under each working condition; Indicates the current of the motor under each working condition; Indicates the speed of the motor; Indicates the output shaft radius of the motor; Indicates the wind speed measured by the differential pressure sensor; represents the fixed drag coefficient of the drum load intensifier; Indicates the sliding resistance coefficient of the drum load intensifier; Indicates the air resistance coefficient of the drum load intensifier.

5. A method for testing heavy vehicles using a light drum according to claim 4, characterized in that: S10207 coefficients ,coefficient and coefficients The determination process is as follows: S1020701: The air butterfly valve (3) is fixed at a specific opening and the motor is started while the wind speed is measured; S1020702: Increase the motor current to a specific wind speed, measure the motor power at that time, and calculate the impeller thrust at that time ; S1020703: Set the wind speed to 10km / h as the step size, and then decrease the wind speed step size one by one. Measure the motor power at this wind speed and calculate the impeller thrust at this wind speed. , we get the quadratic function with the vertical axis being the impeller thrust and the horizontal axis being the wind speed: S1020704: Obtain coefficients based on quadratic functions ,coefficient and coefficients ; S1020705: Calculate the coefficients of the air butterfly valve (3) at all openings ,coefficient and coefficients .

Images