Quantitative characterization and test system and method for transient characteristics of power converter

Abstract

The invention discloses a transient characteristic quantitative characterization and test system and method for a power converter, and the method comprises the steps: building a characterization and test system which comprises a main control module, a test host and a function test module through defining the type of a transient characteristic quantitative characterization test; a starting characteristic test module, a surge current test module, an audio signal suppression characteristic test module and an input stepping voltage response test module are utilized. Through selection and switching of the function test modules of the load current transient response test module and the short circuit recovery characteristic test module, test waveform generation and parameter calculation of different test task types are realized, and output judgment of qualified or unqualified display marks is carried out according to a parameter calculation result.

Description

Technical Field

[0001] The invention relates to a system and method for quantitatively characterizing and testing transient characteristics of a power converter, and belongs to the technical field of electrical signal testing. Background Art

[0002] Power converters are devices that convert one DC voltage into another and provide a continuous and stable DC voltage at the device output. They are widely used in aerospace, communication equipment, and civilian home appliances.

[0003] With the rapid development of electronic technology, the extensive use of semiconductor processes, sealed-converter technology, and high-frequency soft switching has led to the development of power converters with higher power density and conversion efficiency. Although the power converter itself has simple functions, it is composed of passive components, active components, power devices, etc., forming a small electronic system. The reliability of key power devices is particularly critical. Therefore, before the device is delivered to the user, a lot of testing work needs to be done to ensure the reliable application of the device. During the device testing phase, due to the large number of test items, different test boards need to be designed for different test items, and many experimental measuring instruments are required. During the testing process, different responsible persons need to be assigned to perform board-level wiring, measuring instrument observation, and test data recording. This makes the power converter testing work complicated, the test time is long, and the efficiency is low.

[0004] With the continuous advancement of computer testing technology, the development of automated test systems has rapidly expanded. Automated test systems utilize computer control to perform automated testing. This refers to systems that automatically complete stimulus, measurement, data processing, and display or output test results. Automated test systems offer advantages such as high test accuracy, fast test speed, and robust system functionality, earning them significant attention worldwide. Since the 1980s, the United States has invested significant manpower and funding in the development and deployment of a variety of automated test systems for various military branches. However, compared to some developed countries, my country's research in automated testing technology lags behind. Currently, power converter manufacturers still perform manual testing of these devices. Summary of the Invention

[0005] The technical problem solved by the present invention is: in view of the problem that the testing technology of power converter manufacturers in the current existing technology requires manual control and the testing accuracy is not high, a system and method for quantitative characterization and testing of transient characteristics of power converters are proposed.

[0006] The present invention solves the above technical problems by the following technical solutions:

[0007] A power converter transient characteristics quantitative characterization and testing system includes a main control module, a startup characteristics test module, an inrush current test module, an audio signal suppression characteristics test module, an input step voltage response test module, a load current transient response test module, and a short-circuit recovery characteristics test module, wherein:

[0008] The startup characteristic test module, when the test task type is a startup characteristic test, receives the control instruction sent by the main control module and the output voltage of the power converter to be tested, generates a startup voltage test waveform based on the received voltage signal and outputs it for display, calculates the startup delay time and startup overshoot voltage based on the startup voltage test waveform and sends them to the main control module;

[0009] The inrush current test module, when the test task type is an inrush current test, receives the control command sent by the main control module and the input current of the power converter to be tested, generates an input current waveform based on the received current signal and displays it, calculates the maximum input current jump value as the inrush current value based on the input current waveform and sends it to the main control module;

[0010] The audio signal suppression characteristic test module, when the test task type is the audio signal suppression characteristic test, receives the control instruction sent by the main control module, the input current and output voltage of the power converter to be tested, generates the input current waveform and output voltage test waveform according to the received current signal and voltage signal respectively and displays them, determines the input voltage peak value, output voltage peak value and audio signal suppression ratio according to the input current waveform and output voltage test waveform as the test results, and sends them to the main control module;

[0011] Input step voltage response test module, when the test task type is input step voltage response test, receives the control command sent by the main control module and the output voltage of the power converter under test, generates and displays the output voltage waveform based on the received voltage signal, calculates the output voltage peak value and output voltage recovery time based on the output voltage waveform, and sends them to the main control module;

[0012] The load current transient response test module, when the test task type is load current transient response test, receives the control command sent by the main control module and the output voltage of the power converter under test, generates and displays the output voltage waveform based on the received voltage signal, calculates the output voltage peak value and output voltage recovery time based on the output voltage waveform, and sends them to the main control module;

[0013] The short-circuit recovery characteristic test module, when the test task type is a short-circuit recovery characteristic test, receives the control instruction sent by the main control module, the short-circuit current and short-circuit voltage of the power converter under test, generates and displays the short-circuit voltage test waveform based on the received short-circuit current signal and short-circuit voltage signal, calculates the short-circuit power consumption and short-circuit recovery time, and sends them to the main control module;

[0014] The main control module generates corresponding control instructions, current signals or voltage signals according to the test task type, sends them to the test module corresponding to the current test task type, and receives the calculation results returned by each test module to perform threshold judgment on the current test task type, and outputs a qualified display mark or a failed display mark according to the judgment result.

[0015] The method for the main control module to judge the startup delay time and startup overshoot voltage is:

[0016] Compare the start delay time and the start overshoot voltage with the corresponding start threshold value respectively. If the start delay time exceeds the start threshold value, the output will show that the start delay time is unqualified. If the start overshoot voltage exceeds the start threshold value, the output will show that the start overshoot voltage is unqualified.

[0017] When any unqualified display is output, the startup characteristic test result of the power converter to be tested is unqualified; otherwise, the startup characteristic test is passed.

[0018] The method for the main control module to judge the surge current value is:

[0019] The inrush current value is compared with the inrush current threshold. If the inrush current value exceeds the inrush current threshold, the output inrush current test fails and is displayed; otherwise, the inrush current test passes.

[0020] The method for the main control module to judge the input voltage peak, output voltage peak, and audio signal suppression ratio is:

[0021] Compare the input voltage peak value and output voltage peak value with the input voltage threshold value and output voltage threshold value respectively. If the input voltage peak value exceeds the input voltage threshold value, the output voltage peak value will be displayed as unqualified. If the output voltage peak value exceeds the output voltage threshold value, the output voltage peak value will be displayed as unqualified. Otherwise, the inrush current test is passed.

[0022] Compare the audio signal suppression ratio with the audio signal threshold. If the audio signal suppression ratio exceeds the audio signal threshold, an unqualified audio signal suppression ratio display is output.

[0023] When any unqualified display is output, the startup characteristic test result of the power converter under test fails; otherwise, it passes the audio signal suppression characteristic test.

[0024] In the input step voltage response test, the output voltage peak is determined based on the output voltage waveform, and the output voltage recovery time is calculated as follows:

[0025] The difference between the output voltage jump start time and the output voltage stabilization time is taken as the output voltage recovery time;

[0026] The method by which the main control module determines the output voltage peak value and output voltage recovery time is:

[0027] The output voltage peak value and output voltage recovery time are judged by the output voltage threshold and the recovery time threshold respectively. When the output voltage peak value exceeds the output voltage threshold, the output voltage peak value is displayed as unqualified; when the output voltage recovery time exceeds the recovery time threshold, the output recovery time is displayed as unqualified.

[0028] When any unqualified display is output, the input step voltage response test result of the power converter under test is unqualified; otherwise, the input step voltage response test is passed.

[0029] In the load current transient response test, the output voltage peak is determined based on the output voltage waveform, and the output voltage recovery time is calculated as follows:

[0030] The difference between the output voltage jump start time and the output voltage stabilization time is taken as the output voltage recovery time;

[0031] The method by which the main control module determines the output voltage peak value and output voltage recovery time is:

[0032] The output voltage peak value and output voltage recovery time are judged by the output voltage threshold and the recovery time threshold respectively. When the output voltage peak value exceeds the output voltage threshold, the output voltage peak value is displayed as unqualified; when the output voltage recovery time exceeds the recovery time threshold, the output recovery time is displayed as unqualified.

[0033] When any unqualified display is output, the load current transient response test result of the power converter to be tested is unqualified; otherwise, the load current transient response test is passed.

[0034] In the short-circuit recovery characteristic test, the short-circuit voltage peak is determined based on the output voltage waveform, and the short-circuit recovery time is calculated as follows:

[0035] The short-circuit recovery time is the difference between the start of the short-circuit voltage jump and the output voltage stabilization time.

[0036] The main control module determines the short-circuit power consumption and short-circuit recovery time in the following way:

[0037] The short-circuit power consumption threshold and the short-circuit recovery time threshold are used to judge the short-circuit power consumption and the short-circuit recovery time respectively. When the short-circuit power consumption exceeds the short-circuit power consumption threshold, the output short-circuit power consumption is unqualified and displayed; when the short-circuit recovery time exceeds the short-circuit recovery time threshold, the output short-circuit recovery time is unqualified and displayed;

[0038] When any unqualified display is output, the short-circuit recovery characteristic test result of the power converter to be tested is unqualified; otherwise, the short-circuit recovery characteristic test is passed.

[0039] Each test module uses an excitation source to receive control instructions sent by the main control module and generate a square wave signal for controlling the on / off of the circuit; each test module uses a data acquisition module to collect voltage or current data of the power converter under test under the current test task, which is used to generate the test waveform under the current test task;

[0040] Among them, the startup characteristic test module and the inrush current test module share the same excitation source, and the other test modules use different excitation sources.

[0041] The test task type is selected according to the test host. After the test task type is selected, the external test host sends a test start instruction to the main control module. The main control module sends a control instruction and a preset voltage or current signal of the power converter to be tested to the corresponding test module according to the test start instruction; the main control module receives the test waveform returned by the corresponding test module and forwards it to the test host. The test host calculates the test data required for the current test task based on the test waveform and records and saves it.

[0042] The test method implemented based on the power converter transient characteristics quantitative characterization and test system includes:

[0043] The main control module, startup characteristic test module, inrush current test module, audio signal suppression characteristic test module, input step voltage response test module, load current transient response test module and short-circuit recovery characteristic test module are all installed on the power converter to be tested through the EMI filter;

[0044] Select the test task type through the test host, generate a test start instruction for the current test task type and send it to the main control module;

[0045] The main control module sends a control instruction and a preset voltage or current signal of the power converter to be tested to the corresponding test module according to the test start instruction;

[0046] The test module corresponding to the current test task type receives the control instruction and voltage or current signal, generates the test waveform and returns it to the main control module;

[0047] The main control module forwards the received test waveform to the test host to obtain the test data required for the current test task type, and makes a judgment with the corresponding data threshold, and outputs a qualified display mark or a failed display mark for the current test task based on the judgment result.

[0048] The advantages of the present invention compared with the prior art are:

[0049] (1) The present invention provides a system and method for quantitatively characterizing and testing transient characteristics of a power converter. Aiming at the characteristics of long manual testing time and low efficiency in domestic power converter manufacturers, a power converter transient characteristics test system is designed. By utilizing the high-speed switching characteristics of the VDMOS switch tube and the characteristics of adjustable input frequency, a startup characteristic module circuit, an inrush current test circuit, an audio signal suppression characteristic test circuit, an input step voltage (transient) response test circuit, a load current transient response test circuit, and a short-circuit recovery characteristic test circuit are designed. The test is comprehensive and efficient, overcoming the defects of traditional manual testing such as complex wiring and cumbersome operation. One tester replaces six test fixtures, with high integration, optimizing and integrating the resources of six test modules, and reducing the reuse of excitation sources.

[0050] (2) The present invention realizes automatic capture and storage of test waveforms during testing, which is more efficient and accurate than waveform capture by conventional manual oscilloscopes. It can also realize simultaneous online testing of multiple devices of the same type, which is more efficient than manual testing of traditional single devices. The excitation source realizes the output of alternating transient excitation signals through the on-off performance of the MOSFET switch tube, and realizes continuous jump output. The present invention has the advantages of adjustable jump frequency, good repeatability, and high consistency. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A circuit diagram of a startup characteristic test module for the present invention;

[0052] Figure 2 This is a test block diagram of the startup characteristic test module of the present invention;

[0053] Figure 3 This is the circuit diagram of the surge current test module of the present invention;

[0054] Figure 4 This is a circuit diagram of the audio signal suppression characteristic test module of the present invention;

[0055] Figure 5 This is a block diagram of the step voltage response test system of the present invention;

[0056] Figure 6 This is a load step test circuit diagram of the present invention;

[0057] Figure 7 This is a block diagram of a load current transient response characteristic test module of the present invention;

[0058] Figure 8 This is the circuit diagram of the short-circuit recovery characteristic test module of the present invention. DETAILED DESCRIPTION

[0059] A system and method for quantitative characterization and testing of transient characteristics of a power converter are disclosed. By defining the type of transient characteristic quantitative characterization test, a characterization and testing system including a main control module, a test host, and a functional test module is established. Functional test modules including a startup characteristic test module, an inrush current test module, an audio signal suppression characteristic test module, an input step voltage response test module, a load current transient response test module, and a short-circuit recovery characteristic test module are selected and switched to achieve test waveform generation and parameter calculation for different test task types. A pass or fail display mark is output based on the parameter calculation results.

[0060] In the power converter transient characteristics quantitative characterization and test system:

[0061] The startup characteristic test module, when the test task type is a startup characteristic test, receives the control instruction sent by the main control module and the output voltage of the power converter to be tested, generates a startup voltage test waveform based on the received voltage signal and outputs it for display, calculates the startup delay time and startup overshoot voltage based on the startup voltage test waveform and sends them to the main control module;

[0062] The inrush current test module, when the test task type is an inrush current test, receives the control command sent by the main control module and the input current of the power converter to be tested, generates an input current waveform based on the received current signal and displays it, calculates the maximum input current jump value as the inrush current value based on the input current waveform and sends it to the main control module;

[0063] The audio signal suppression characteristic test module, when the test task type is the audio signal suppression characteristic test, receives the control instruction sent by the main control module, the input current and output voltage of the power converter to be tested, generates the input current waveform and output voltage test waveform according to the received current signal and voltage signal respectively and displays them, determines the input voltage peak value, output voltage peak value and audio signal suppression ratio according to the input current waveform and output voltage test waveform as the test results, and sends them to the main control module;

[0064] Input step voltage response test module, when the test task type is input step voltage response test, receives the control command sent by the main control module and the output voltage of the power converter under test, generates and displays the output voltage waveform based on the received voltage signal, calculates the output voltage peak value and output voltage recovery time based on the output voltage waveform, and sends them to the main control module;

[0065] The load current transient response test module, when the test task type is load current transient response test, receives the control command sent by the main control module and the output voltage of the power converter under test, generates and displays the output voltage waveform based on the received voltage signal, calculates the output voltage peak value and output voltage recovery time based on the output voltage waveform, and sends them to the main control module;

[0066] The short-circuit recovery characteristic test module, when the test task type is a short-circuit recovery characteristic test, receives the control instruction sent by the main control module, the short-circuit current and short-circuit voltage of the power converter under test, generates and displays the short-circuit voltage test waveform based on the received short-circuit current signal and short-circuit voltage signal, calculates the short-circuit power consumption and short-circuit recovery time, and sends them to the main control module;

[0067] The main control module generates corresponding control instructions, current signals or voltage signals according to the test task type, sends them to the test module corresponding to the current test task type, and receives the calculation results returned by each test module to perform threshold judgment on the current test task type, and outputs a qualified display mark or a failed display mark according to the judgment result.

[0068] The method by which the main control module judges the startup delay time and startup overshoot voltage is as follows:

[0069] Compare the start delay time and the start overshoot voltage with the corresponding start threshold value respectively. If the start delay time exceeds the start threshold value, the output will show that the start delay time is unqualified. If the start overshoot voltage exceeds the start threshold value, the output will show that the start overshoot voltage is unqualified.

[0070] When any unqualified display is output, the startup characteristic test result of the power converter to be tested is unqualified; otherwise, the startup characteristic test is passed.

[0071] The method by which the main control module judges the inrush current value is:

[0072] The inrush current value is compared with the inrush current threshold. If the inrush current value exceeds the inrush current threshold, the output inrush current test fails and is displayed; otherwise, the inrush current test passes.

[0073] The main control module determines the input voltage peak, output voltage peak, and audio signal suppression ratio in the following way:

[0074] Compare the input voltage peak value and output voltage peak value with the input voltage threshold value and output voltage threshold value respectively. If the input voltage peak value exceeds the input voltage threshold value, the output voltage peak value will be displayed as unqualified. If the output voltage peak value exceeds the output voltage threshold value, the output voltage peak value will be displayed as unqualified. Otherwise, the surge current test is passed.

[0075] Compare the audio signal suppression ratio with the audio signal threshold. If the audio signal suppression ratio exceeds the audio signal threshold, an unqualified audio signal suppression ratio display is output.

[0076] When any unqualified display is output, the startup characteristic test result of the power converter under test fails; otherwise, it passes the audio signal suppression characteristic test.

[0077] In the input step voltage response test, the output voltage peak is determined based on the output voltage waveform, and the output voltage recovery time is calculated as follows:

[0078] The difference between the output voltage jump start time and the output voltage stabilization time is taken as the output voltage recovery time;

[0079] The method by which the main control module determines the output voltage peak value and output voltage recovery time is:

[0080] The output voltage peak value and output voltage recovery time are judged by the output voltage threshold and the recovery time threshold respectively. When the output voltage peak value exceeds the output voltage threshold, the output voltage peak value is displayed as unqualified; when the output voltage recovery time exceeds the recovery time threshold, the output recovery time is displayed as unqualified.

[0081] When any unqualified display is output, the input step voltage response test result of the power converter under test is unqualified; otherwise, the input step voltage response test is passed.

[0082] In the load current transient response test, the output voltage peak is determined based on the output voltage waveform, and the output voltage recovery time is calculated as follows:

[0083] The difference between the output voltage jump start time and the output voltage stabilization time is taken as the output voltage recovery time;

[0084] The method by which the main control module determines the output voltage peak value and output voltage recovery time is:

[0085] The output voltage peak value and output voltage recovery time are judged by the output voltage threshold and the recovery time threshold respectively. When the output voltage peak value exceeds the output voltage threshold, the output voltage peak value is displayed as unqualified; when the output voltage recovery time exceeds the recovery time threshold, the output recovery time is displayed as unqualified.

[0086] When any unqualified display is output, the load current transient response test result of the power converter to be tested is unqualified; otherwise, the load current transient response test is passed.

[0087] In the short-circuit recovery characteristic test, the short-circuit voltage peak is determined based on the output voltage waveform, and the short-circuit recovery time is calculated as follows:

[0088] The short-circuit recovery time is the difference between the start of the short-circuit voltage jump and the output voltage stabilization time.

[0089] The main control module determines the short-circuit power consumption and short-circuit recovery time in the following way:

[0090] The short-circuit power consumption threshold and the short-circuit recovery time threshold are used to judge the short-circuit power consumption and the short-circuit recovery time respectively. When the short-circuit power consumption exceeds the short-circuit power consumption threshold, the output short-circuit power consumption is unqualified and displayed; when the short-circuit recovery time exceeds the short-circuit recovery time threshold, the output short-circuit recovery time is unqualified and displayed;

[0091] When any unqualified display is output, the short-circuit recovery characteristic test result of the power converter to be tested is unqualified; otherwise, the short-circuit recovery characteristic test is passed.

[0092] Each test module uses an excitation source to receive control instructions sent by the main control module and generate a square wave signal for controlling the on / off of the circuit; each test module uses a data acquisition module to collect voltage or current data of the power converter under test under the current test task, which is used to generate the test waveform under the current test task;

[0093] Among them, the startup characteristic test module and the inrush current test module share the same excitation source, and the other test modules use different excitation sources.

[0094] The test task type is selected according to the test host. After the test task type is selected, the external test host sends a test start instruction to the main control module. The main control module sends a control instruction and a preset voltage or current signal of the power converter to be tested to the corresponding test module according to the test start instruction; the main control module receives the test waveform returned by the corresponding test module and forwards it to the test host. The test host calculates the test data required for the current test task based on the test waveform and records and saves it.

[0095] The following is further described in conjunction with the accompanying drawings and preferred embodiments:

[0096] In the current embodiment, the test method implemented by the power converter transient characteristics quantitative characterization and testing system includes the following steps:

[0097] The main control module, startup characteristic test module, inrush current test module, audio signal suppression characteristic test module, input step voltage response test module, load current transient response test module and short-circuit recovery characteristic test module are all installed on the power converter to be tested through the EMI filter;

[0098] Select the test task type through the test host, generate a test start instruction for the current test task type and send it to the main control module;

[0099] The main control module sends a control instruction and a preset voltage or current signal of the power converter to be tested to the corresponding test module according to the test start instruction;

[0100] The test module corresponding to the current test task type receives the control instruction and voltage or current signal, generates the test waveform and returns it to the main control module;

[0101] The main control module forwards the received test waveform to the test host to obtain the test data required for the current test task type, and makes a judgment with the corresponding data threshold, and outputs a qualified display mark or a failed display mark for the current test task based on the judgment result.

[0102] Furthermore, the power converter loading module can load multiple power converters to be tested and EMI filters used in conjunction with the power converters, and lead out all the pins of the power converters and EMI filters;

[0103] The startup characteristic test module includes a first excitation source providing a first excitation voltage signal; the startup characteristic test module is connected to the power converter loading module and the main control module, and the startup characteristic test circuit measures the output voltage of the power converter and the output voltage of the first excitation source during the startup process under the control of the main control module, and sends the results to the main control module;

[0104] The inrush current test module is connected to the power converter loading module and the main control module, and measures the input current of the power converter under the control of the main control module and sends it to the main control module;

[0105] The audio signal suppression characteristic test module is connected to the power converter loading module and the main control module, and measures the input voltage value and output voltage value of the power converter under the control of the main control module and sends them to the main control module;

[0106] The input step voltage response test module is connected to the power converter loading module and the main control module, and measures the output voltage peak value and output voltage recovery time of the power converter under the fourth excitation source under the control of the main control module, and sends the results to the main control module;

[0107] The load current transient response test module is connected to the power converter loading module and the main control module, and under the control of the main control module, measures the output voltage peak and output voltage recovery time of the power converter under the fifth excitation source and sends them to the main control module;

[0108] The short-circuit recovery characteristic test module is connected to the power converter loading module and the main control module, and measures the short-circuit voltage and short-circuit current of the power converter under the control of the main control module and sends them to the main control module;

[0109] The main control module receives the control command of the test host and controls the electronic switch according to the control command to realize the switching of each functional module; receives the data sent by each functional module and sends it to the test host through the communication module;

[0110] The test host receives the output voltage of the power converter and the output voltage of the first excitation source sent by the main control module and obtains the startup voltage test waveform, startup delay time and startup overshoot voltage; receives the input current and obtains the input current waveform and input surge current value; receives the input voltage value and the output voltage value and obtains the input voltage test waveform, output voltage test waveform, input voltage peak value, output voltage peak value, and audio signal suppression ratio; receives the output voltage under the fourth excitation source and obtains the output voltage waveform, output voltage peak value and output voltage recovery time; receives the output voltage under the fifth excitation source and obtains the output voltage waveform, output voltage peak value and output voltage recovery time; receives the short-circuit voltage and short-circuit current and obtains the short-circuit voltage test waveform, short-circuit power consumption and short-circuit recovery time.

[0111] Among them, the test host receives the output voltage of the power converter and the output voltage of the first excitation source sent by the main control module and obtains the startup voltage test waveform, startup delay time and startup overshoot voltage; receives the input current and obtains the input current waveform and input surge current value; receives the input voltage value and the output voltage value and obtains the input voltage test waveform, output voltage test waveform, input voltage peak, output voltage peak, and audio signal suppression ratio; receives the output voltage under the fourth excitation source, and obtains the output voltage waveform, output voltage peak and output voltage recovery time; receives the output voltage under the fifth excitation source, and obtains the output voltage waveform, output voltage peak and output voltage recovery time; receives the short-circuit voltage and short-circuit current, and obtains the short-circuit voltage test waveform, short-circuit power consumption and short-circuit recovery time.

[0112] Startup characteristic test module circuit Figure 1 As shown, it includes a first excitation source, a startup characteristic excitation circuit and a first data acquisition module. The test block diagram is as follows Figure 2 As shown, the first excitation source provides a 0-1Hz square wave signal to control the on-off of the first MOSFET switch tube. The startup characteristic excitation circuit receives an input DC voltage of 100V. Under the control of the first MOSFET switch tube, it outputs a 0 to 100V alternating transient excitation signal to the input end of the EMI filter; the first data acquisition module collects the input voltage and output voltage of the power converter and sends them to the main control module. The input voltage is the output voltage of the first excitation source.

[0113] Inrush current test module circuit Figure 3As shown, it includes a first excitation source, an inrush current detection circuit and a second data acquisition module. The second excitation source provides a 0-1Hz square wave signal to control the on and off of the second MOSFET switch tube. The startup characteristic excitation circuit receives an input DC voltage of 100V and, under the control of the second MOSFET switch tube, outputs a 0 to 100V alternating transient excitation signal to the input end of the power converter; the second data acquisition module collects the input voltage of the power converter and converts it into input current, and sends the input current to the main control module.

[0114] Audio signal suppression characteristic test module circuit Figure 4 As shown, it includes a third excitation source, a first voltage synthesis excitation circuit and a third data acquisition module; the third excitation source provides a 20-20KHz square wave signal to control the on and off of the third MOSFET switch tube, the first voltage synthesis excitation circuit receives a 20V input DC voltage, and under the control of the third MOSFET switch tube, outputs a 0 to 20V alternating transient excitation signal, and superimposes a 100V DC signal, outputting a 100 to 120V alternating transient excitation signal to the input end of the EMI filter; the third data acquisition module collects the input voltage and output voltage of the power converter and sends them to the main control module.

[0115] The block diagram of the input step voltage response test module is as follows: Figure 5 As shown, the test circuit is as Figure 6 As shown, it includes a fourth excitation source, a second voltage synthesis excitation circuit and a fourth data acquisition module; the fourth excitation source provides a 50Hz square wave signal to control the on and off of the fourth MOSFET switch tube, the second voltage synthesis excitation circuit receives a 20V input DC voltage, and under the control of the fourth MOSFET switch tube, it outputs a 0 to 20V alternating transient excitation signal, and superimposes a 100V DC signal, and outputs a 100 to 120V alternating transient excitation signal to the input end of the EMI filter; the third data acquisition module collects the output voltage and output voltage recovery time of the power converter, and sends them to the main control module.

[0116] Load current transient response test module circuit is as follows Figure 7 As shown, it includes a fifth excitation source, a load step test circuit and a fifth data acquisition module; the fifth excitation source provides a 20-20KHz square wave signal to control the on and off of the fifth MOSFET switch tube. Under the control of the fifth MOSFET switch tube, the output load is alternately transiently switched between no-load and full-load; a 100V DC voltage is connected to the input end of the power converter, and the fifth data acquisition module collects the output voltage and output voltage recovery time of the power converter and sends them to the main control module.

[0117] Short circuit recovery characteristic test module such as Figure 8As shown, it includes a sixth excitation source, a short-circuit recovery characteristic test circuit and a sixth data acquisition module; the sixth excitation source provides a 0-1 Hz square wave signal to control the on and off of the sixth MOSFET switch tube. Under the control of the sixth MOSFET switch tube, the output load is alternately transiently switched between no-load and short-circuit; a 100V DC voltage is connected to the input end of the power converter, and the sixth data acquisition module collects the short-circuit voltage and short-circuit current of the power converter and sends them to the main control module.

[0118] The test host sends control commands to the main control module to switch and select each test module; it controls the communication module to transmit data;

[0119] In the startup characteristic test mode, the startup characteristic module is controlled to be turned on, the output voltage of the power converter and the output voltage of the first excitation source sent by the main control module are received, and the startup voltage test waveform is obtained and output for display, and the time difference between the jump starting moment value of the output voltage of the first excitation source and the jump stable value of the output voltage of the power converter is calculated as the startup delay time. When the startup delay time exceeds the threshold, the output startup delay time is unqualified; the difference between the maximum jump value and the stable value of the output voltage of the power converter is calculated as the startup overshoot voltage. When the startup overshoot voltage exceeds the threshold, the output overshoot voltage is unqualified;

[0120] In the inrush current test mode, the inrush current test module is controlled to start, receive the input current, obtain the input current waveform and display it, and calculate the maximum jump value of the input current as the inrush current value. When the inrush current value exceeds the threshold, the output inrush current value is unqualified;

[0121] In the audio signal suppression characteristic test mode, the audio signal suppression characteristic test module is controlled to start, the input voltage value and the output voltage value are received, the input voltage test waveform and the output voltage test waveform are obtained and displayed, and the input voltage peak value, the output voltage peak value, and the audio signal suppression ratio are calculated;

[0122] In the input step voltage response test mode, the input step voltage response test module is controlled to be turned on, the output voltage under the fourth excitation source is received, the output voltage waveform is obtained and displayed, and the output voltage peak value is calculated. When the output voltage peak value exceeds the threshold value, the output voltage peak value fails to meet the requirements; the difference between the output voltage jump start time and the output voltage stabilization time is calculated as the output voltage recovery time. When the output voltage recovery time exceeds the threshold value, the output voltage recovery time fails to meet the requirements;

[0123] In the load current transient response test mode, the load current transient response test module is controlled to be turned on, the output voltage under the fifth excitation source is received, the output voltage waveform is obtained and displayed, and the output voltage peak value is calculated. When the output voltage peak value exceeds the threshold value, the output voltage peak value fails to meet the requirements; the difference between the output voltage jump start time and the output voltage stabilization time is calculated as the output voltage recovery time. When the output voltage recovery time exceeds the threshold value, the output voltage recovery time fails to meet the requirements;

[0124] In the short-circuit recovery characteristic test mode, the short-circuit recovery characteristic test module is controlled to be turned on, the short-circuit voltage and short-circuit current are received, the short-circuit voltage test waveform is obtained and displayed, the short-circuit power consumption is calculated, and the difference between the short-circuit voltage starting time and the output voltage stabilization time is calculated as the short-circuit recovery time. When the short-circuit recovery time exceeds the threshold, the output short-circuit recovery time fails.

[0125] Although the present invention has been disclosed above in terms of preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solutions of the present invention by using the methods and technical contents disclosed above without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solutions of the present invention shall fall within the scope of protection of the technical solutions of the present invention.

[0126] The contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

Claims

1. A system for quantitative characterization and testing of transient characteristics of a power converter, characterized by: It includes main control module, startup characteristics test module, inrush current test module, audio signal suppression characteristics test module, input step voltage response test module, load current transient response test module and short circuit recovery characteristics test module, among which: The startup characteristic test module, when the test task type is a startup characteristic test, receives the control instruction sent by the main control module and the output voltage of the power converter to be tested, generates a startup voltage test waveform based on the received voltage signal and outputs it for display, calculates the startup delay time and startup overshoot voltage based on the startup voltage test waveform and sends them to the main control module; The inrush current test module, when the test task type is an inrush current test, receives the control command sent by the main control module and the input current of the power converter to be tested, generates an input current waveform based on the received current signal and displays it, calculates the maximum input current jump value as the inrush current value based on the input current waveform and sends it to the main control module; The audio signal suppression characteristic test module, when the test task type is the audio signal suppression characteristic test, receives the control instruction sent by the main control module, the input current and output voltage of the power converter to be tested, generates the input current waveform and output voltage test waveform according to the received current signal and voltage signal respectively and displays them, determines the input voltage peak value, output voltage peak value and audio signal suppression ratio according to the input current waveform and output voltage test waveform as the test results, and sends them to the main control module; Input step voltage response test module, when the test task type is input step voltage response test, receives the control command sent by the main control module and the output voltage of the power converter under test, generates and displays the output voltage waveform based on the received voltage signal, calculates the output voltage peak value and output voltage recovery time based on the output voltage waveform, and sends them to the main control module; The load current transient response test module, when the test task type is load current transient response test, receives the control command sent by the main control module and the output voltage of the power converter under test, generates and displays the output voltage waveform based on the received voltage signal, calculates the output voltage peak value and output voltage recovery time based on the output voltage waveform, and sends them to the main control module; The short-circuit recovery characteristic test module, when the test task type is a short-circuit recovery characteristic test, receives the control instruction sent by the main control module, the short-circuit current and short-circuit voltage of the power converter under test, generates and displays the short-circuit voltage test waveform based on the received short-circuit current signal and short-circuit voltage signal, calculates the short-circuit power consumption and short-circuit recovery time, and sends them to the main control module; The main control module generates corresponding control instructions according to the test task type, sends them to the test module corresponding to the current test task type, and receives the calculation results returned by each test module to perform threshold judgment on the current test task type, and outputs a qualified display mark or a failed display mark according to the judgment result.

2. The power converter transient characteristics quantitative characterization and testing system according to claim 1, characterized in that: The method for the main control module to judge the startup delay time and startup overshoot voltage is: Compare the start delay time and the start overshoot voltage with the corresponding start threshold value respectively. If the start delay time exceeds the start threshold value, the output will show that the start delay time is unqualified. If the start overshoot voltage exceeds the start threshold value, the output will show that the start overshoot voltage is unqualified. When any unqualified display is output, the startup characteristic test result of the power converter to be tested is unqualified; otherwise, the startup characteristic test is passed.

3. The power converter transient characteristics quantitative characterization and testing system according to claim 1, characterized in that: The method for the main control module to judge the surge current value is: The inrush current value is compared with the inrush current threshold. If the inrush current value exceeds the inrush current threshold, the output inrush current test fails and is displayed; otherwise, the inrush current test passes.

4. The power converter transient characteristics quantitative characterization and testing system according to claim 1, characterized in that: The method for the main control module to judge the input voltage peak, output voltage peak, and audio signal suppression ratio is: Compare the input voltage peak value and output voltage peak value with the input voltage threshold value and output voltage threshold value respectively. If the input voltage peak value exceeds the input voltage threshold value, the output voltage peak value will be displayed as unqualified. If the output voltage peak value exceeds the output voltage threshold value, the output voltage peak value will be displayed as unqualified. Otherwise, the surge current test is passed. Compare the audio signal suppression ratio with the audio signal threshold. If the audio signal suppression ratio exceeds the audio signal threshold, an unqualified audio signal suppression ratio display is output. When any unqualified display is output, the startup characteristic test result of the power converter under test fails; otherwise, it passes the audio signal suppression characteristic test.

5. The power converter transient characteristics quantitative characterization and testing system according to claim 1, characterized in that: In the input step voltage response test, the output voltage peak is determined based on the output voltage waveform, and the output voltage recovery time is calculated as follows: The difference between the output voltage jump start time and the output voltage stabilization time is taken as the output voltage recovery time; The method by which the main control module determines the output voltage peak value and output voltage recovery time is: The output voltage peak value and output voltage recovery time are judged by the output voltage threshold and the recovery time threshold respectively. When the output voltage peak value exceeds the output voltage threshold, the output voltage peak value is displayed as unqualified; when the output voltage recovery time exceeds the recovery time threshold, the output recovery time is displayed as unqualified. When any unqualified display is output, the input step voltage response test result of the power converter under test is unqualified; otherwise, the input step voltage response test is passed.

6. The power converter transient characteristics quantitative characterization and testing system according to claim 1, characterized in that: In the load current transient response test, the output voltage peak is determined based on the output voltage waveform, and the output voltage recovery time is calculated as follows: The difference between the output voltage jump start time and the output voltage stabilization time is taken as the output voltage recovery time; The method by which the main control module determines the output voltage peak value and output voltage recovery time is: The output voltage peak value and output voltage recovery time are judged by the output voltage threshold and the recovery time threshold respectively. When the output voltage peak value exceeds the output voltage threshold, the output voltage peak value is displayed as unqualified; when the output voltage recovery time exceeds the recovery time threshold, the output recovery time is displayed as unqualified. When any unqualified display is output, the load current transient response test result of the power converter to be tested is unqualified; otherwise, the load current transient response test is passed.

7. The power converter transient characteristics quantitative characterization and testing system according to claim 1, characterized in that: In the short-circuit recovery characteristic test, the short-circuit voltage peak is determined based on the output voltage waveform, and the short-circuit recovery time is calculated as follows: The short-circuit recovery time is the difference between the start of the short-circuit voltage jump and the output voltage stabilization time. The main control module determines the short-circuit power consumption and short-circuit recovery time in the following way: The short-circuit power consumption threshold and the short-circuit recovery time threshold are used to judge the short-circuit power consumption and the short-circuit recovery time respectively. When the short-circuit power consumption exceeds the short-circuit power consumption threshold, the output short-circuit power consumption is unqualified and displayed; when the short-circuit recovery time exceeds the short-circuit recovery time threshold, the output short-circuit recovery time is unqualified and displayed; When any unqualified display is output, the short-circuit recovery characteristic test result of the power converter to be tested is unqualified; otherwise, the short-circuit recovery characteristic test is passed.

8. The power converter transient characteristics quantitative characterization and testing system according to claim 1, characterized in that: Each test module uses an excitation source to receive control instructions sent by the main control module and generate a square wave signal for controlling the on / off of the circuit; each test module uses a data acquisition module to collect voltage or current data of the power converter under test under the current test task, which is used to generate the test waveform under the current test task; Among them, the startup characteristic test module and the inrush current test module share the same excitation source, and the other test modules use different excitation sources.

9. The power converter transient characteristics quantitative characterization and testing system according to claim 8, characterized in that: The test task type is selected according to the test host. After the test task type is selected, the external test host sends a test start instruction to the main control module. The main control module sends a control instruction and a preset voltage or current signal of the power converter to be tested to the corresponding test module according to the test start instruction; the main control module receives the test waveform returned by the corresponding test module and forwards it to the test host. The test host calculates the test data required for the current test task based on the test waveform and records and saves it.

10. A test method implemented by the power converter transient characteristics quantitative characterization and test system according to claim 9, characterized in that include: The main control module, startup characteristic test module, inrush current test module, audio signal suppression characteristic test module, input step voltage response test module, load current transient response test module and short-circuit recovery characteristic test module are all installed on the power converter to be tested through the EMI filter; Select the test task type through the test host, generate a test start instruction for the current test task type and send it to the main control module; The main control module sends a control instruction and a preset voltage or current signal of the power converter to be tested to the corresponding test module according to the test start instruction; The test module corresponding to the current test task type receives the control instruction and voltage or current signal, generates the test waveform and returns it to the main control module; The main control module forwards the received test waveform to the test host to obtain the test data required for the current test task type, and makes a judgment with the corresponding data threshold, and outputs a qualified display mark or a failed display mark for the current test task based on the judgment result.

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