Automatic test system for vehicle brushless cooling fan controller

Abstract

The invention discloses an automatic testing system for a vehicle brushless cooling fan controller. The automatic testing system comprises a testing upper computer, a programmable direct current load, a signal generator, USBLIN conversion equipment, a USB acquisition board card, a rotating speed sensor, a short circuit switch, an open circuit switch, a PLC, a fan blade limiting stopper, the brushless cooling fan controller and a brushless fan. The test upper computer is connected with the signal generator, the USBLIN conversion equipment and the programmable direct current load, and the signal generator, the USBLIN conversion equipment and the programmable direct current load are connected with the brushless cooling fan controller. Aiming at 12V and 24V platforms, the fan rotating speed can be detected, part of faults can be simulated, the product development efficiency is improved, the labor cost is reduced, and the test time is shortened.

Description

Technical Field

[0001] The invention relates to the technical field of brushless cooling fan testing, in particular to an automatic testing system for a brushless cooling fan controller for a vehicle. Background Art

[0002] Common automotive brushless cooling fans on the market can be divided into 12V and 24V platforms according to the power supply voltage, and the main communication methods are PWM and LIN.

[0003] The automotive brushless cooling fan controller drives the fan to a specific speed based on an external control signal (PWM / LIN).

[0004] In addition to speed testing, the automotive brushless cooling fan controller also includes tests for over-voltage and under-voltage, VDS short circuit, phase line open circuit, stall, downwind start, and static start-stop. The functions are complex, the testing is time-consuming, and the labor cost is high.

[0005] Therefore, an automatic test system for a brushless cooling fan controller for a vehicle is proposed. Summary of the invention

[0006] The purpose of the present invention is to provide an automated testing system for a brushless cooling fan controller for a vehicle, which can not only detect the fan speed but also simulate some faults for 12V and 24V platforms, thereby improving product development efficiency and reducing labor costs and testing time.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] An automated testing system for a brushless cooling fan controller for a vehicle, comprising a testing host computer, a programmable DC load, a signal generator, a USBLIN conversion device, a USB acquisition board, a speed sensor, a short-circuit switch, an open-circuit switch, a PLC, a fan blade limiter, a brushless cooling fan controller, and a brushless fan;

[0009] The test host computer is connected to a signal generator, a USBLIN conversion device, and a programmable DC load, and the signal generator, USBLIN conversion device, and programmable DC load are connected to a brushless cooling fan controller;

[0010] The brushless cooling fan controller is connected to an open circuit switch through three phase lines, the open circuit switch is connected to a brushless fan, the brushless fan is connected to a speed sensor, the speed sensor is connected to a USB acquisition card, and the USB acquisition board is connected to a test host computer;

[0011] The brushless cooling fan controller is connected to a USB acquisition board;

[0012] The test host computer is connected to the PLC, and the PLC is respectively connected to a fan blade limiter, a circuit breaker, and an open circuit switch. The fan blade limiter is connected to a brushless fan, and the circuit breaker is connected to the open circuit switch through three phase lines.

[0013] Furthermore, the test host computer sets the voltage and then communicates with the programmable DC load.

[0014] Furthermore, the test host computer outputs the speed command to the brushless cooling fan controller through the PWM speed regulation curve / LIN protocol.

[0015] Furthermore, the rotation speed sensor converts the rotation speed signal into an electrical signal and connects it to a USB acquisition board, and the USB acquisition board acquires the electrical signal and outputs it to a test host computer.

[0016] Furthermore, the rotation speed sensor is connected to the USB acquisition board through the FO port.

[0017] Furthermore, the test host computer detects the current output value of the programmable DC load, and when the current output value is lower than the shutdown judgment current threshold, the current shutdown voltage is recorded.

[0018] Furthermore, the test host computer controls the short-circuit switch to close through a short-circuit command PLC.

[0019] Furthermore, the test host computer controls the open circuit switch to close by short-circuiting the PLC.

[0020] Furthermore, the test host computer controls the fan blade limiter to fix the fan blade through a stall command PLC, thereby simulating a stall condition.

[0021] Furthermore, the test host computer controls the DC load to turn off the power supply of the controller, and the fan enters the coasting state to simulate the downwind starting condition.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] This test system supports the test of automotive cooling fan controllers on 12V and 24V platforms. After the host computer sets the voltage, it communicates with the programmable DC load to provide power for the brushless cooling fan controller.

[0024] This test system supports two communication modes with the fan controller: 1. LIN protocol. 2. PWM. The host computer outputs the speed command to the brushless cooling fan controller according to the controller's PWM speed regulation curve / LIN protocol;

[0025] This test system can detect the speed of the fan in real time with high precision. The speed sensor converts the speed signal into an electrical signal through the reflective strip on the fan blade. The USB acquisition board collects this signal and outputs it to the host computer. The host computer compares the feedback speed with the expected speed, automatically calculates the speed error, and determines whether the speed test is qualified.

[0026] This system supports static start-stop, downwind start, and speed regulation function tests.

[0027] This test system supports fault simulation of VDS short circuit, phase line open circuit, over-voltage, under-voltage, and stall. The host computer simulates the fault through the programmed test sequence;

[0028] This test system collects the signal of the controller fault feedback port (FO) through the USB acquisition board and outputs it to the host computer to analyze whether the fault feedback signal is correct; BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 The invention is a block diagram of the automatic test system for the automotive brushless cooling fan controller. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0031] Embodiment 1:

[0032] See also Figure 1 , the present invention provides a technical solution:

[0033] An automated testing system for a brushless cooling fan controller for a vehicle, comprising a testing host computer, a programmable DC load, a signal generator, a USBLIN conversion device, a USB acquisition board, a speed sensor, a short-circuit switch, an open-circuit switch, a PLC, a fan blade limiter, a brushless cooling fan controller, and a brushless fan;

[0034] Connect the test host computer to the signal generator, USBLIN conversion device, and programmable DC load (the test host computer sets the voltage and then communicates with the programmable DC load), and connect the signal generator, USBLIN conversion device, and programmable DC load to the brushless cooling fan controller (the test host computer outputs the speed command to the brushless cooling fan controller through the PWM speed regulation curve / LIN protocol);

[0035] Make the brushless cooling fan controller connected to the open circuit switch through three phase lines, connect the open circuit switch to the brushless fan, connect the brushless fan to the speed sensor, connect the speed sensor to the USB acquisition card, connect the USB acquisition board to the test host computer, connect the brushless cooling fan controller to the USB acquisition board, connect the test host computer to the PLC, connect the PLC to the fan blade limiter, the circuit breaker, and the open circuit switch respectively, connect the fan blade limiter to the brushless fan, and connect the circuit breaker to the open circuit switch through three phase lines;

[0036] The speed sensor converts the speed signal into an electrical signal and connects it to the USB acquisition board. The USB acquisition board collects the electrical signal and outputs it to the test host computer. The speed sensor is connected to the USB acquisition board through the FO port.

[0037] In the above scenario:

[0038] The test host computer detects the current output value of the programmable DC load. When the current output value is lower than the shutdown judgment current threshold, the current shutdown voltage is recorded. The test host computer controls the short-circuit switch to be closed through a short-circuit command to the PLC. The test host computer controls the open-circuit switch to be closed through a short-circuit command to the PLC. The test host computer controls the fan blade limiter to fix the fan blade through a stall command to the PLC, thereby simulating a stall condition. The test host computer controls the DC load to turn off the power supply of the controller, and the fan enters the gliding state to simulate the downwind starting condition.

[0039] Working principle:

[0040] This test system supports two communication modes with the fan controller: 1. LIN protocol, 2. PWM;

[0041] (1) Speed ​​test

[0042] When using LIN protocol communication, the test host computer sends the speed command to the brushless cooling fan controller through the USBLIN conversion device. The user needs to enter the LIN speed test sequence on the host computer. There can be multiple sequences to meet the test commands at different speeds. Each sequence includes: target speed, speed regulation time, sampling interval, total sampling time, and speed error;

[0043] After sending the target speed, the test system waits for the speed adjustment time, then obtains the speed signal returned by the USB acquisition board at every sampling time and calculates the speed error. This sequence ends when the total sampling time is reached. If the error is within the set range, this sequence test passes, otherwise the test fails.

[0044] When using PWM communication, the test host computer sends a PWM signal of a specific frequency and duty cycle to the brushless cooling fan controller through a signal generator. The test host computer automatically converts the PWM and speed mapping relationship into the target speed for subsequent calculation of the speed error. This mapping relationship can be manually set on the host computer. There can be multiple PWM speed test sequences to meet the test commands at different speeds. Each sequence includes: PWM frequency, PWM duty cycle, speed regulation time, sampling interval, total sampling time, and speed error.

[0045] After sending the PWM signal, the test system waits for the speed regulation time, then obtains the speed signal returned by the USB acquisition board at every sampling time and calculates the speed error. This sequence ends when the total sampling time is reached. If the error is within the set range, this sequence test passes, otherwise the test fails.

[0046] (2) Over-voltage and under-voltage test

[0047] The host computer performs over-voltage and under-voltage tests by setting a programmable DC load;

[0048] The overvoltage test sequence includes: overvoltage shutdown voltage, overvoltage recovery voltage, voltage adjustment interval time, shutdown judgment current threshold;

[0049] When the brushless fan is operating normally, the voltage is increased by 0.1V at each voltage adjustment interval, and the maximum increase is 1V higher than the overvoltage shutdown voltage. The upper computer detects the current output value of the programmable DC load. When the current output value is lower than the shutdown judgment current threshold, the current shutdown voltage is recorded, and then the voltage is reduced by 0.1V at each voltage adjustment interval, and the maximum reduction is 1V lower than the overvoltage recovery voltage. When the current output threshold is greater than the shutdown judgment current threshold, the current recovery voltage is recorded and the data is saved;

[0050] The undervoltage test sequence includes: undervoltage shutdown voltage, undervoltage recovery voltage, voltage adjustment interval, and shutdown judgment current threshold;

[0051] When the brushless fan is operating normally, the voltage is reduced by 0.1V at each voltage adjustment interval, and the maximum reduction is 1V lower than the undervoltage shutdown voltage. The upper computer detects the current output value of the programmable DC load. When the current output value is lower than the shutdown judgment current threshold, the current shutdown voltage is recorded, and then the voltage is increased by 0.1V at each voltage adjustment interval, and the maximum increase is 1V higher than the undervoltage recovery voltage. When the current output threshold is greater than the shutdown judgment current threshold, the current recovery voltage is recorded and the data is saved.

[0052] (3) VDS short circuit

[0053] When the fan is operating normally, the test host computer sends a short-circuit command to the PLC, and the PLC controls the short-circuit switch to close, creating a phase-to-phase short circuit in the brushless fan. If the VDS short-circuit function is normal, the brushless cooling fan controller will immediately shut down the output of the three-phase inverter. The test host computer reads the fault feedback signal through the FO fault port of the brushless cooling fan controller to determine whether the fault type is correct. If the fan has not stopped for protection 1ms after the short-circuit command is issued, the host computer will immediately cut off the power supply to the controller to prevent equipment damage.

[0054] (4) Open circuit between phases

[0055] When the brushless fan is operating normally, the test host computer sends an open-circuit command to the PLC, and the PLC controls the open-circuit switch to disconnect, creating an open-circuit situation between phases of the brushless fan. If the phase-to-phase open-circuit protection function is normal, the brushless cooling fan controller will control the fan to stop. The test host computer reads the fault feedback signal through the FO fault port of the brushless cooling fan controller to determine whether the fault type is correct. If the fan still does not stop for protection 5S after the short-circuit command is issued, the test host computer will output 0 speed to the motor, and the PLC will close the open-circuit switch to eliminate the fault.

[0056] (5) Stalling

[0057] When the brushless fan is in the stop zone, the test host computer sends a stall command to the PLC. The PLC controls the fan blade limiter to fix the fan blade, simulating the stall condition. Then the host computer gives a new target speed, and the controller drives the fan to rotate. At this time, the fan blade cannot rotate normally. If the stall protection function is normal, the brushless cooling fan controller will control the fan to stop after a delay. The test host computer reads the fault feedback signal through the FO fault port of the brushless cooling fan controller to determine whether the fault type is correct. If the fan has not stopped for protection 5S after the stall command is issued, the host computer will output 0 speed to the motor to eliminate the fault.

[0058] (6) Downwind start

[0059] When the brushless fan is running at medium and high speed, the test host computer controls the DC load to turn off the power supply of the controller, and the fan enters the coasting state to simulate the downwind starting condition. After 500ms, the test host computer controls the DC load to power on again, and the speed sensor is used to monitor the change of the fan speed. This process can be repeated according to the set number of times. The system records and saves the speed and current data during the entire test process.

[0060] (7) Stationary start-stop

[0061] This system uses the host computer to write the start-stop test sequence and control the programmable DC load to perform the start-stop test. The start-stop test sequence includes: setting voltage, limiting current, power-on time, power-off time, target speed, and number of repetitions. During the power-on time, the host computer gives the target speed and turns on the power supply to the brushless cooling fan controller. The fan starts and runs normally. After the power-on time is exceeded, the host computer turns off the power supply to the brushless cooling fan controller, and the fan slides freely to stop. The system will repeat this process and record the voltage, current, power, and speed data.

[0062] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An automated testing system for a brushless cooling fan controller for a vehicle, characterized in that: Including testing host computer, programmable DC load, signal generator, USBLIN conversion equipment, USB acquisition board, speed sensor, short circuit switch, open circuit switch, PLC, fan blade limiter, brushless cooling fan controller, brushless fan; The test host computer is connected to a signal generator, a USBLIN conversion device, and a programmable DC load, and the signal generator, USBLIN conversion device, and programmable DC load are connected to a brushless cooling fan controller; The brushless cooling fan controller is connected to an open circuit switch through three phase lines, the open circuit switch is connected to a brushless fan, the brushless fan is connected to a speed sensor, the speed sensor is connected to a USB acquisition card, and the USB acquisition board is connected to a test host computer; The brushless cooling fan controller is connected to a USB acquisition board; The test host computer is connected to the PLC, and the PLC is respectively connected to a fan blade limiter, a circuit breaker, and an open circuit switch. The fan blade limiter is connected to a brushless fan, and the circuit breaker is connected to the open circuit switch through three phase lines.

2. The automatic test system for a brushless cooling fan controller for a vehicle according to claim 1, characterized in that: The test host computer sets the voltage and then communicates with the programmable DC load.

3. The automatic test system for a brushless cooling fan controller for a vehicle according to claim 1, characterized in that: The test host computer outputs the speed command to the brushless cooling fan controller through the PWM speed regulation curve / LIN protocol.

4. The automatic test system for a brushless cooling fan controller for a vehicle according to claim 1, characterized in that: The rotation speed sensor converts the rotation speed signal into an electrical signal which is connected to a USB acquisition board, and the USB acquisition board acquires the electrical signal and outputs it to a test host computer.

5. The automatic test system for a brushless cooling fan controller for a vehicle according to claim 1, characterized in that: The rotation speed sensor is connected to the USB acquisition board through the FO port.

6. The automated testing system for a brushless cooling fan controller for a vehicle according to claim 1, characterized in that: The test host computer detects the current output value of the programmable DC load, and when the current output value is lower than the shutdown judgment current threshold, the current shutdown voltage is recorded.

7. The automated testing system for a brushless cooling fan controller for a vehicle according to claim 1, characterized in that: The test host computer controls the short-circuit switch to close through a short-circuit command PLC.

8. The automated testing system for a brushless cooling fan controller for a vehicle according to claim 1, characterized in that: The test host computer controls the open circuit switch to close by short-circuiting the PLC.

9. The automatic test system for a brushless cooling fan controller for a vehicle according to claim 1, characterized in that: The test host computer controls the fan blade limiter to fix the fan blade through the stall command PLC, thereby simulating the stall condition.

10. The automatic test system for a brushless cooling fan controller for a vehicle according to claim 1, characterized in that: The test host computer controls the DC load to turn off the power supply of the controller, and the fan enters the coasting state to simulate the downwind starting condition.

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