Fan test system, test method and test device thereof

Abstract

The invention relates to a fan test system, a test method and a test device thereof, independent power supply of four to six channels is realized through a programmable direct-current power supply module, and self-adaptive test of fans with voltage specifications such as 12V / 24V is supported; the single fan test channel integrates a fan interface, a PWM drive circuit, a current sampling loop and an FG waveform acquisition circuit, and synchronously acquires current and rotating speed signals through a high-speed converter; in the initialization stage, PWM parameters and an FG pull-up mode are configured, and current surge and rotating speed waveforms are synchronously collected after starting; calculating a current effective value, a rotating speed and a waveform width-to-width ratio / height ratio in real time, and comparing an actually measured waveform with a standard waveform through a cross-correlation algorithm; and a limit test is supported, the fan power supply adaptability is evaluated, and finally a test report containing Pass / Fail conclusions is generated and is in butt joint with a factory quality management system. The single-chip microcomputer communicates with the industrial control computer through an LAN, test parameter issuing, waveform real-time display and automatic uploading of a test result to a user MES system are achieved, and the fan test method and device have the effect of improving the fan test efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of fan testing, in particular to a fan testing system, a testing method and a testing device thereof. BACKGROUND

[0002] At present, single-channel or double-channel testing equipment is generally used in the field of fan performance testing, and the hardware architecture is fixed and the number of channels is limited. The traditional scheme adjusts the power supply voltage manually and manually switches the resistance network to match the fan feedback signal (such as the pull-up level of the FG speed signal), which results in a single test time of more than 5 minutes, and only 1-2 fans can be tested in parallel. For mass-produced products such as computer cooling fans, such a scheme cannot meet the needs of the flow line batch detection, especially when mixed-line production of multi-specification fans, frequent hardware adjustment is easy to introduce operation errors, and the test efficiency is more than 60% lower than the automation requirement. In addition, the single-channel design leads to high hardware cost, which is difficult to meet the efficiency requirements in large-scale production scenarios. SUMMARY

[0003] In order to improve the test efficiency of the fan, the present application provides a fan testing system, a testing method and a testing device thereof.

[0004] The fan testing system, the testing method and the testing device thereof provided by the present application adopt the following technical scheme: First aspect A fan testing system, comprising a programmable DC power supply module, a fan testing channel module, a single-chip microcomputer and an industrial computer; The programmable DC power supply module is electrically connected to the fan through a wire, used to output adjustable voltage to the fan, and connected to the single-chip microcomputer through a digital signal control line to receive voltage adjustment instructions; The fan testing channel module comprises a fan interface, a PWM drive circuit, a current sampling loop and an FG waveform acquisition circuit; The fan interface comprises a power supply pin, a PWM control pin and an FG feedback pin, used to physically connect the fan; The input end of the PWM drive circuit is connected to the single-chip microcomputer, and the output end is connected to the PWM control pin, used to amplify the PWM signal generated by the single-chip microcomputer to drive the fan; A high-speed A / D converter is connected between the current sampling loop and the single-chip microcomputer, one end of the current sampling loop is connected to the negative electrode of the programmable DC power supply module, and the other end is grounded, and the current sampling loop is used to input the voltage signal to the high-speed A / D converter; A pull-up resistor network is connected between the FG feedback pin and the single-chip microcomputer.

[0005] The single-chip microcomputer communicates with the industrial computer through a LAN interface, and is configured to generate a PWM signal, control a programmable DC power supply module, collect current and FG signals through the high-speed A / D converter, and calculate current effective value, FG rotating speed and waveform parameters in real time. The industrial computer is configured to configure test parameters, display waveform data, and upload test results to an MES system through a TCP / IP protocol.

[0006] By adopting the above technical solutions, the programmable DC power supply module is physically connected with the fan structure, compatible power supply for fans of different voltage specifications is achieved, the PWM driving circuit drives the fan to rotate, the probability of occurrence of the situation that a large current impact causes damage to the fan is reduced, the FG waveform acquisition circuit can filter out high-frequency noise, and the reliability of the rotating speed signal is improved, the LAN communication architecture of the single-chip microcomputer and the industrial computer supports real-time data interaction and remote control, at the same time, the test structure is uploaded to the MES system through the TCP / IP protocol, and automatic tracing of test results is achieved. Since it can support multi-channel expansion, it is suitable for fan testing requirements of different needs.

[0007] Preferably, the pull-up resistor network comprises a first resistor, a second resistor and a third resistor connected in series, one end of the first resistor away from the second resistor is connected to the programmable DC power supply module through an analog switch, and the third resistor away from the second resistor is grounded.

[0008] By adopting the above technical solutions, the pull-up mode of the first resistor, the second resistor and the third resistor is switched through the analog switch, the FG signal level standard of fans of different specifications is flexibly adapted, compatibility problems caused by traditional fixed pull-up resistors are avoided, the cost of hardware re-soldering or resistor replacement is reduced, and the universality is improved.

[0009] Preferably, the resolution of the high-speed A / D converter is greater than or equal to 12 bits, and the sampling rate is greater than or equal to 10 kHz, an operational amplifier is connected between the current sampling circuit and the single-chip microcomputer, the analog channel of the high-speed A / D converter is connected to the output end of the operational amplifier and the output end of the FG waveform acquisition circuit, and the digital channel is connected to the single-chip microcomputer.

[0010] By adopting the above technical solutions, a high-precision quantization of current / voltage signals can be realized by a resolution of more than 12 bits, and current inrush and rotating speed fluctuation at the moment of fan start can be captured by a sampling rate of more than 10 kHz.

[0011] Preferably, the output voltage accuracy of the programmable DC power supply module is ±0.1%, and the ripple is less than or equal to 50 mV, to receive instructions of the single-chip microcomputer, support multi-channel independent power supply, and each channel is connected to the fan interface through a wire.

[0012] By adopting the technical scheme, the voltage precision of ±0.1% and the ripple of ≤50 mV ensure the stability of the test power supply, and avoid introducing additional errors due to power supply fluctuation.

[0013] The second aspect A fan testing device, comprising a test bench and a circuit board, the test bench is provided with a fan interface panel and a state indicator lamp, and the circuit board integrates the programmable DC power supply module, the single-chip microcomputer, the high-speed A / D converter and the fan testing channel module in the first aspect, the current and the FG signal thereof are connected in parallel to the high-speed A / D converter through an analog switch, the common end of the analog switch is connected with an analog channel of the high-speed A / D converter, and the address end of the analog switch is connected to the single-chip microcomputer.

[0014] By adopting the technical scheme, the test bench and the circuit board are integrated, the programmable power supply module, the single-chip microcomputer, the A / D converter and the fan testing channel module are modularly packaged, and the 4-6 channel signals are collected in parallel and time-multiplexed through the analog switch and the fan interface panel.

[0015] Preferably, the state indicator lamp is electrically connected with the single-chip microcomputer, and comprises a normal indicator lamp and an abnormal indicator lamp, and is used for indicating the test result of the fan.

[0016] By adopting the technical scheme, the linkage design of the state indicator lamp and the single-chip microcomputer provides intuitive test feedback, the operator can quickly locate the faulty fan through the indicator lamp, without checking the computer interface one by one, and the risk of misoperation is reduced.

[0017] The third aspect A fan testing method, applying the fan testing system in the first aspect, comprising the following steps: S1, parameter configuration: the industrial computer sends instructions to the single-chip microcomputer through LAN, sets the output voltage of the programmable DC power supply module, the PWM frequency and the duty cycle of the single-chip microcomputer, and selects the FG pull-up resistor mode through the analog switch; S2, signal collection: the single-chip microcomputer outputs a PWM signal to drive the fan to work, and the high-speed A / D converter synchronously collects the voltage signal and the FG feedback signal of the current sampling loop; S3, data processing: the single-chip microcomputer calculates the effective value of the current, calculates the rotating speed through the FG signal period, and analyzes the width / height ratio of the waveform, the industrial computer compares the measured waveform with the preset standard waveform, and marks the abnormality; S4, result output: the industrial computer generates a test report containing the Pass / Fail conclusion, and automatically uploads the result to the MES system through the TCP / IP protocol.

[0018] By implementing these technical solutions, the entire process, from parameter configuration and signal acquisition to data processing, is fully automated, eliminating manual input errors. For example, the industrial computer automatically transmits PWM parameters via the LAN, eliminating manual input errors. High-speed A / D synchronously acquires current and speed signals, ensuring consistent data timestamps and facilitating subsequent waveform correlation analysis. Automatic test report generation and upload to the MES system ensure seamless traceability of test data, complying with ISO 9001 quality management system requirements.

[0019] Preferably, in S2, when the fan starts, the single chip microcomputer captures the inrush current peak value of the current sampling circuit at a sampling rate of 10kHz, and if the inrush current peak value exceeds 150% of the rated current, it is determined that the startup is abnormal.

[0020] By adopting the above technical solution, the current peak is captured at a 10kHz sampling rate during the fan startup phase, which can effectively identify potential defects such as motor winding short circuits and bearing seizures.

[0021] Preferably, in S3, the industrial control computer calculates the similarity between the measured waveform and the standard waveform through a cross-correlation algorithm, and triggers an alarm when the similarity is less than 90%, and simultaneously records the timestamp and parameter deviation value of the abnormal point.

[0022] By employing this technical solution, a cross-correlation algorithm quantitatively assesses signal consistency by calculating the Pearson correlation coefficient between the measured waveform and the reference waveform. When the similarity is less than 90%, the system automatically marks waveform distortion points (such as FG signal pulse loss or excessive current ripple) and records the timestamp and parameter deviation.

[0023] Preferably, a limit test step is also included, in which a programmable DC power supply module is used to simulate ±10% rated voltage fluctuation, with a duration of ≥2 minutes, and the current ripple coefficient and speed fluctuation ratio of the fan under voltage fluctuation are collected.

[0024] By adopting the above technical solution and simulating ±10% rated voltage fluctuations for more than one minute, the fan's adaptability to unstable power grids or aging power supplies can be evaluated. This test fills the gaps in conventional no-load testing and ensures the fan's long-term reliable operation under complex operating conditions.

[0025] In summary, this application includes at least one of the following beneficial technical effects: 1. Independent power supply and precise voltage regulation are achieved through a programmable DC power module, combined with an analog switch switching mechanism for FG pull-up resistors, making it compatible with fans of different voltage specifications. 2. High-speed A / D converter captures current and speed waveform details in real time, combined with single-chip surge current peak detection, waveform parameter calculation, and industrial computer correlation similarity algorithm, can accurately identify fan start-up abnormalities, speed fluctuations, signal distortion, and other hidden defects; 3. Seamless connection of industrial computer and MES system, realizing full-process digitization from data acquisition, report generation to quality traceability. Test results automatically generate PDF reports and include Pass / Fail conclusions, avoiding manual recording errors and meeting ISO9001 traceability requirements. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 is a schematic diagram of the overall structure of a fan testing device according to the present application.

[0027] Figure 2 is a flowchart of a fan testing method according to the present application.

[0028] Figure 3 is an example of a display interface of a fan testing system according to the present application on an industrial computer.

[0029] Figure 4 is a schematic diagram of signal transmission between modules of a fan testing system according to the present application.

[0030] Figure 5 is a system interface diagram of a fan testing system according to the present application.

[0031] Reference signs: 1, test bench; 2, fan interface panel; 3, state knowledge, etc.; 31, normal indicator light; 32, abnormal indicator light; JP1, fan interface; JP2, programmable DC power supply module; RS2, sampling resistor; R1, first resistor; R2, second resistor; R3, third resistor; R61, current-limiting resistor. DETAILED DESCRIPTION

[0032] The following will be described in detail in combination with the accompanying drawings. Figures 1-5 The present application will be further described in detail.

[0033] First, the embodiments of the present application disclose a fan testing system, referring to Figure 3 and Figure 4The programmable DC power module JP2, the fan test channel module, the single-chip microcomputer and the industrial computer are electrically connected with the fan through wires, and are used to output adjustable voltage to the fan to drive the fan to work, and are connected with the single-chip microcomputer through digital signal control lines to receive voltage adjustment instructions. The fan test channel module includes a fan interface JP1, a PWM drive circuit, a current sampling loop and an FG waveform acquisition circuit. The fan interface includes a power supply pin, a PWM control pin and an FG feedback pin, and is used to physically connect the fan. The input end of the PWM drive circuit is connected with the single-chip microcomputer, and the output end is connected with the PWM control pin, and is used to amplify the PWM signal generated by the single-chip microcomputer to drive the fan. The high-speed A / D converter is connected between the current sampling loop and the single-chip microcomputer. One end of the current sampling loop is connected with the negative electrode of the programmable DC power module, and the other end is grounded. The current sampling loop is used to input the voltage signal to the high-speed A / D converter. The pull-up resistor network is connected between the FG feedback pin FG and the single-chip microcomputer. The single-chip microcomputer communicates with the industrial computer through the LAN interface, and is used to generate the PWM signal, control the programmable DC power module JP2, collect the current and FG signals through the high-speed A / D converter, and implement the calculation of the current effective value, the FG rotating speed and the waveform parameters. The industrial computer is used to configure test parameters and display waveform data, and uploads the test structure to the MES system through the TCP / IP protocol.

[0034] Specifically, the fan interface JP1 is provided with a PWM pin, an FG pin, a FAN+ pin and a FAN- pin, which are used to be connected with the fan. The FAN+ programmable DC power module JP2 is connected with the power supply positive pin FAN+ of the fan interface JP1 through wires to provide a voltage suitable for the voltage specification of the fan for the fan interface JP1, and the programmable DC power module JP2 is connected with the single-chip microcomputer through digital signal control lines to receive the voltage adjustment instructions sent by the single-chip microcomputer (MCU processor).

[0035] It should be noted that the high-speed A / D converter includes A / D FG waveform acquisition and A / D current waveform acquisition, and the following description will not be distinguished.

[0036] Further, the current sampling circuit comprises a sampling resistor RS2, an operational amplifier and a high-speed A / D converter, one end of the sampling resistor RS2 is connected to the FAN-pin of the fan interface JP1, the other end is suspended, the 3-pin of the operational amplifier is connected between the FAN-pin of the fan interface JP1 and the sampling resistor RS2, the 2-pin of the operational amplifier is connected to the suspended end of the sampling resistor RS2, and the high-speed A / D converter is connected between the 1-pin of the operational amplifier and the single-chip microcomputer, thus the voltage signal between the two ends of the sampling resistor RS2 is input to the non-inverting input terminal of the operational amplifier, the inverting input terminal is suspended, and the output terminal transmits the amplified voltage signal (such as 0-5V) to the analog channel of the high-speed A / D converter, the high-speed A / D converter converts the analog voltage signal into a digital signal and transmits it to the single-chip microcomputer through the data bus.

[0037] The pull-up resistor network comprises a first resistor R1, a second resistor R2 and a third resistor R3 connected in series, one end of the first resistor R1 away from the second resistor R2 is connected to the programmable DC power module JP2 through an analog switch, and one end of the third resistor away from the second resistor is suspended and grounded. The FG-pin of the fan interface JP1 is connected between the first resistor R1 and the second resistor R2, the voltage signal of the FG-pin of the fan interface passes through the pull-up resistor network, filters out high-frequency noise, and the high-speed A / D converter is connected between the second resistor R2 and the third resistor R3, and the output is transmitted to the single-chip microcomputer after filtering out high-frequency noise, so as to realize the measurement of the signal frequency.

[0038] The pull-up resistor network has three working modes. When one end of the first resistor R1 is connected to the programmable DC power module JP2 and the other end is connected to the FG-pin of the fan interface JP1 through an analog switch, it corresponds to the "fan voltage high" mode; when one end of the second resistor R2 is connected to the 5V voltage provided by the system and the other end is connected to the FG-pin of the fan interface JP1 through an analog switch, it corresponds to the "system 5V high" mode; when one end of the third resistor R3 is suspended and the other end is connected to the FG-pin of the fan interface JP1 through an analog switch, it corresponds to the "suspended" mode. The control end of the analog switch is connected to the single-chip microcomputer, and the pull-up mode is switched through the level signal.

[0039] It should be noted that the PWM driving circuit is a conventional driving circuit, which is provided with a current-limiting resistor R61, and the PWM signal is amplified to the driving current required by the fan through the connection of the current-limiting resistor R61 and the PWM-pin of the fan interface JP1, which will not be described in detail here.

[0040] Correspondingly, the resolution of the high-speed A / D converter is greater than or equal to 12 bits, the sampling rate is greater than or equal to 10 kHz, an operational amplifier is connected between the current sampling circuit and the single-chip microcomputer, the analog channel of the high-speed A / D converter is connected to the output end of the operational amplifier and the output end of the FG waveform acquisition circuit respectively, and the digital channel is connected to the single-chip microcomputer. The high-precision quantization of the current / voltage signal can be realized by the resolution of more than 12 bits, and the current surge and speed fluctuation at the instant of fan starting can be captured by the sampling rate of more than 10 kHz.

[0041] Meanwhile, the output voltage precision of the programmable DC power module is ±0.1%, and the ripple is less than or equal to 50 mV, so as to receive the instructions of the single-chip microcomputer, support multi-channel independent power supply, and connect each channel to the fan interface through a wire. The voltage precision of ±0.1% and the ripple of less than or equal to 50 mV ensure the stability of the test power supply and avoid introducing additional errors due to power fluctuations.

[0042] Further, the embodiment of the application discloses a fan testing device, referring to Figure 1 , which comprises a test table 1 and a circuit board. The test table is provided with a fan interface JP1 panel 2 and a state indicator lamp 3. The circuit board integrates a programmable DC power module JP2, a single-chip microcomputer, a high-speed A / D converter and a fan testing channel module of a fan testing system. The current and FG signals are connected in parallel to the high-speed A / D converter through an analog switch. The common end of the analog switch is connected to the analog channel of the high-speed A / D converter. The address end of the analog switch is connected to the single-chip microcomputer. The test table 1 and the circuit board are integrated. The programmable power module, the single-chip microcomputer, the A / D converter and the fan testing channel module are modularly packaged. The fan interface panel and the analog switch realize the parallel acquisition and time division multiplexing of 4-6 channel signals.

[0043] Correspondingly, the state indicator lamp 3 is electrically connected to the single-chip microcomputer and comprises a normal indicator lamp 31 and an abnormal indicator lamp 32, which are used for indicating the test result of the fan. The linkage design of the state indicator lamp and the single-chip microcomputer provides intuitive test feedback. The operator can quickly locate the faulty fan through the indicator lamp without checking the computer interface one by one, thereby reducing the risk of misoperation.

[0044] In a third aspect, a fan testing method is disclosed, referring to Figures 2-5 , which is applied to the fan testing system and comprises the following steps.

[0045] S1, parameter configuration: the industrial computer sends instructions to the single-chip microcomputer through LAN, sets the output voltage of the programmable DC power module, the PWM frequency and duty cycle of the single-chip microcomputer, and selects the FG pull-up resistor mode through the analog switch; The industrial computer sends instructions (such as "channel 1 voltage = 12V, PWM frequency = 25kHz, duty cycle = 50%") to the single-chip microcomputer through the LAN interface, and the single-chip microcomputer transmits the instructions to the programmable DC power supply module JP2 to adjust the output voltage to the rated value of the fan, S2, signal acquisition: the single-chip microcomputer outputs a PWM signal to drive the fan to work, and a high-speed A / D converter synchronously acquires the voltage signal of the current sampling loop and the FG feedback signal; the single-chip microcomputer sends a level signal to the analog switch according to the fan model to switch the FG pull-up resistor working mode.

[0046] The single-chip microcomputer outputs a PWM signal, which is limited by the current-limiting resistor R61 to drive the fan PWM pin. The power device works in a switching mode, and the voltage across the fan is adjusted. The starting current of the fan is sampled through the sampling resistor RS2, and the generated voltage signal is input to the A / D converter. The FG signal is input to the single-chip microcomputer after filtering, and the period of the square wave is measured.

[0047] S3, data processing: the single-chip microcomputer calculates the current effective value, calculates the speed through the FG signal period, and analyzes the width / height ratio of the waveform. The industrial computer compares the measured waveform with the preset standard waveform and marks the abnormality. Current effective value: the root mean square of 100 sampling points is calculated, and the formula is: , error <0.5%, error <0.5%.

[0048] , where, is the i-th current instantaneous value (unit: ampere, A) collected by the high-speed A / D converter.

[0049] n: number of sampling points (such as 100 points, corresponding to a 10ms sampling duration, and the sampling rate is 10kHz).

[0050] Speed calculation: if the fan outputs three FG pulses per revolution, and the measured period is 50ms, the formula is: , where the period is a complete waveform period of the FG signal (unit: seconds, s), which is measured by the single-chip microcomputer timer.

[0051] Pulse number: the number of FG pulses output by the fan per revolution (determined by the fan structure, such as 3 pulses / revolution), so the speed is 60 / (0.05x3)=4000RPM.

[0052] Width / height ratio: calculate the high-level time / period of the FG waveform to evaluate the stability of the duty cycle.

[0053] Industrial computer waveform analysis: receive 1000-point waveform data uploaded by the single-chip microcomputer, and perform cross-correlation operation with the standard waveform (stored in the database), and the formula is: , similarity <90% is marked as abnormal.

[0054] wherein, is the amplitude of the measured waveform (such as current or FG voltage) at time ; and : the amplitude of the standard waveform at time ; : the mean of the measured / standard waveform; N: the number of waveform data points (such as 1000 points, corresponding to a 100 ms duration); : the waveform time offset.

[0055] S4, result output: the industrial computer generates a test report containing the Pass / Fail conclusion and automatically uploads the results to the MES system via the TCP / IP protocol.

[0056] The industrial computer encapsulates the test results (such as current 3.2A, speed 1200RPM, Pass) into JSON format and uploads them to the "fan test" database table of the MES system via the TCP / IP protocol, associating the fan SN code with the production line station number.

[0057] In S2, when the fan starts, the single-chip microcomputer captures the inrush current peak of the current sampling loop at a sampling rate of 10kHz. If the inrush current peak exceeds 150% of the rated current, it is determined that the start is abnormal. The current peak is captured at a sampling rate of 10kHz during the fan start-up stage, which can effectively identify potential defects such as motor winding short circuit and bearing jamming, and simultaneously generate a PDF report containing waveform comparison graphs, parameter lists and determination conclusions, supporting electronic signature and printing archive.

[0058] Correspondingly, the single-chip microcomputer triggers the high-speed A / D to enter burst sampling mode (sampling rate increased to 50kHz) at the same time as the fan start signal (PWM duty cycle from 0%→100%), continuously collecting current data for the first 100ms. The peak detection algorithm: real-time comparison of the current sampling value with the historical maximum value, recording the start current peak (such as a fan with rated current of 2A, threshold set to 3A), exceeding which is determined as start-up abnormality, and the abnormality indicator light works.

[0059] At the same time, in step S3, the industrial computer calculates the similarity between the measured waveform and the standard waveform through the cross-correlation algorithm, and triggers an alarm when the similarity is <90%, while recording the timestamp and parameter deviation value of the abnormal point. The cross-correlation algorithm quantitatively evaluates the signal consistency by calculating the Pearson correlation coefficient of the measured waveform and the standard waveform. When the similarity is <90%, the system automatically marks the waveform distortion point (such as FG signal missing pulse, current ripple too large) and records the timestamp and parameter deviation.

[0060] First, the measured waveform and the standardized waveform need to be de-meaned, normalized, and processed to eliminate DC bias and amplitude differences. The 1-second long waveform is divided into 10 100ms windows, and the cross-correlation coefficient is calculated for each window. If the similarity of any window is <90%, it is determined to be abnormal. When a sharp drop in similarity is detected, the timestamp corresponding to the abnormal point is marked, and the current mutation value and FG frequency jump value at that time are extracted.

[0061] In addition, it also includes a limit test link. Through the programmable DC power module JP2, ±10% rated voltage fluctuation is simulated, with a duration of ≥2min. The current ripple coefficient and speed fluctuation ratio of the fan under voltage fluctuation are collected. The programmable DC power module JP2 receives single-chip microcomputer instructions, with a period of 100 milliseconds, and superimposes ±10% disturbance on the basis of the rated voltage (such as 12V fan test voltage circulating between 10.8V-13.2V), for 2 minutes. The single-chip microcomputer collects current ripple (effective value) and FG cycle fluctuation at a sampling rate of 2kHz, and calculates: Current ripple coefficient: (standard value ≤8%); Where, : the effective value of current ripple (unit: A), that is, the amplitude of the alternating component.

[0062] : the average value of the DC component of the current (unit: A).

[0063] Rotational fluctuation rate: ; Where, : the maximum / minimum speed during the test (unit: RPM).

[0064] : the average speed during the test (unit: RPM) If the current ripple coefficient is >15% or the speed fluctuation rate is >10%, it is determined that the fan power supply suppression capability is insufficient.

[0065] The implementation principle of the fan test system, test method and test device of the embodiment of the application is as follows: a programmable DC power supply module JP is used to provide adjustable voltage for the fan and support multi-channel expansion, a PWM drive circuit in the fan test channel module receives a PWM signal generated by a single-chip microcomputer through a current limiting resistor R61 to drive the fan, a current sampling loop collects a current signal through a sampling resistor RS2 and an operational amplifier, an FG waveform acquisition circuit acquires a speed feedback signal by using a pull-up resistor network (a first resistor R1 / a second resistor R2 / a third resistor R3) in combination with an analog switch switching mode, the two types of signals are transmitted to the single-chip microcomputer through a high-speed A / D converter to calculate data such as current effective value, speed, waveform parameters and the like in real time, an industrial computer receives data through a LAN interface and performs waveform comparison, cross-correlation analysis and the like, and simultaneously uploads test results to a MES system through a TCP / IP protocol; the test method covers parameter configuration, multi-channel synchronous acquisition, start-up surge detection, limit condition simulation (such as ±10% voltage fluctuation) and automatic report generation, realizes precise test and digital management of performance indexes such as fan current, speed and stability, and improves test efficiency, compatibility and intelligent level through hardware modular design and software algorithm optimization.

[0066] The above are preferred embodiments of the application, and do not limit the protection scope of the application, so that: equivalent changes made according to the structure, shape, principle of the application should be covered within the protection scope of the application.

Claims

1. A fan testing system, characterized by: The programmable DC power supply module, the fan test channel module, the single-chip microcomputer and the industrial computer are included. The programmable DC power supply module is electrically connected with the fan through wires, is used for outputting adjustable voltage to the fan, and is connected with the single-chip microcomputer through a digital signal control line to receive voltage adjustment instructions. The fan test channel module includes a fan interface, a PWM drive circuit, a current sampling loop and an FG waveform acquisition circuit. The fan interface includes a power supply pin, a PWM control pin and an FG feedback pin, and is used for physically connecting the fan. The input end of the PWM drive circuit is connected with the single-chip microcomputer, and the output end is connected with the PWM control pin, and is used for amplifying the PWM signal generated by the single-chip microcomputer to drive the fan. A high-speed A / D converter is connected between the current sampling loop and the single-chip microcomputer, one end of the current sampling loop is connected with the negative electrode of the programmable DC power supply module, and the other end is grounded, and the current sampling loop is used for inputting voltage signals to the high-speed A / D converter. A pull-up resistor network is connected between the FG feedback pin and the single-chip microcomputer. The single-chip microcomputer communicates with the industrial computer through a LAN interface, is used for generating PWM signals, controlling the programmable DC power supply module, collecting current and FG signals through the high-speed A / D converter, and calculating current effective value, FG rotating speed and waveform parameters in real time, and the industrial computer is used for configuring test parameters, displaying waveform data, and uploading test results to an MES system through a TCP / IP protocol.

2. The fan testing system of claim 1, wherein: The pull-up resistor network includes a first resistor, a second resistor and a third resistor connected in series, one end of the first resistor away from the second resistor is connected to the programmable DC power supply module through an analog switch, and the third resistor away from the second resistor is grounded.

3. The fan testing system of claim 1, wherein: The resolution of the high-speed A / D converter is greater than or equal to 12 bits, and the sampling rate is greater than or equal to 10 kHz, an operational amplifier is connected between the current sampling loop and the single-chip microcomputer, the analog channel of the high-speed A / D converter is connected to the output end of the operational amplifier and the output end of the FG waveform acquisition circuit respectively, and the digital channel is connected to the single-chip microcomputer.

4. The fan testing system of claim 1, wherein: The output voltage precision of the programmable DC power supply module is ±0.1%, and the ripple is less than or equal to 50 mV, the single-chip microcomputer instructions are received, multiple channels are supported for independent power supply, and each channel is connected to the fan interface through wires.

5. A fan testing apparatus characterized by: The test table and the circuit board are included, the fan interface panel and the state indicator lamp are arranged on the test table, the circuit board integrates the programmable DC power supply module, the single-chip microcomputer, the high-speed A / D converter and the fan test channel module in any one of claims 1-4, the current and FG signals are connected to the high-speed A / D converter through analog switches in parallel, the common end of the analog switch is connected to the analog channel of the high-speed A / D converter, and the address end of the analog switch is connected to the single-chip microcomputer.

6. The test device of claim 5, wherein: The state indicator lamp is electrically connected with the single-chip microcomputer, includes a normal indicator lamp and an abnormal indicator lamp, and is used for indicating the test result of the fan.

7. A fan testing method applied to the fan testing system of any one of claims 1-4, characterized in that, The test table and the circuit board are included, the fan interface panel and the state indicator lamp are arranged on the test table, the circuit board integrates the programmable DC power supply module, the single-chip microcomputer, the high-speed A / D converter and the fan test channel module in any one of claims 1-4, the current and FG signals are connected to the high-speed A / D converter through analog switches in parallel, the common end of the analog switch is connected to the analog channel of the high-speed A / D converter, and the address end of the analog switch is connected to the single-chip microcomputer. S1, parameter configuration: the industrial computer sends instructions to the single-chip microcomputer through LAN to set the output voltage of the programmable DC power module, the PWM frequency and duty cycle of the single-chip microcomputer, and select the FG pull-up resistor mode through an analog switch; S2, signal acquisition: the single-chip microcomputer outputs a PWM signal to drive the fan to work, and a high-speed A / D converter synchronously acquires the voltage signal of the current sampling loop and the FG feedback signal; S3, data processing: the single-chip microcomputer calculates the current effective value, calculates the rotating speed through the FG signal period, and analyzes the waveform width ratio / high-low ratio, and the industrial computer compares the measured waveform with the preset standard waveform and marks the abnormality; S4, result output: the industrial computer generates a test report containing the Pass / Fail conclusion, and automatically uploads the result to the MES system through the TCP / IP protocol.

8. In the S2, when the fan starts, the single-chip microcomputer captures the inrush current peak of the current sampling loop at a sampling rate of 10 kHz, and if the inrush current peak exceeds 150% of the rated current, it is determined that the start-up is abnormal.

9. The position limiting roller according to claim 1, wherein: According to the test method of claim 7, wherein in the S3, the industrial computer calculates the similarity of the measured waveform and the standard waveform through a cross-correlation algorithm, and if the similarity is less than 90%, an alarm is triggered, and the time stamp and parameter deviation value of the abnormal point are recorded.

10. The test method of claim 7, wherein: It also includes a limit test link, which simulates ±10% rated voltage fluctuation through a programmable DC power module, with a duration of ≥2min, and acquires the current ripple coefficient and rotating speed fluctuation ratio of the fan under voltage fluctuation.

Images