Dynamic test system for driving circuit of motor driver

Abstract

The invention provides a dynamic test system for a driving circuit of a motor driver. The dynamic test system comprises a control module, a driving module, a power supply module, a test tool and a data processing platform, the control module is used for controlling on and off of the tested power device and on and off of various relays, and receiving parameters and instructions sent by the data processing platform; the driving module is used for realizing various topologies and driving circuit forms of the inverter circuit; the power supply module outputs a driving voltage for the driving module and a power supply voltage for the control module; different driving voltages are used for driving signals of different power devices; the test tool comprises a heating tool, various voltage and current test devices and a structural member for fixing the devices at test points of the driving module; and the data processing platform is used for classifying voltage and current waveforms and identifying key data. According to the invention, the efficiency, the accuracy and the intelligent degree of the double-pulse test can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of power electronic device testing, and in particular to a dynamic testing system for a motor driver driving circuit. Background Art

[0002] AC servo drives have been widely used in industrial production. Power devices play an important role in the inverter circuit of servo drives and are key components for energy conversion and power conversion. Applying power devices including IGBT, SIMOS, and SiCMOS to the inverter circuit of the drive, and designing reasonable drive circuit parameters to avoid high-voltage oscillation and signal crosstalk, and reducing electromagnetic interference are technical difficulties.

[0003] At present, standard dynamic and static test equipment is mainly used to test the parameter characteristics and limit capabilities of power devices, which can more accurately predict their switching losses, electrical stress and other usage conditions.

[0004] However, standard dynamic and static test equipment is only for a single device and is not universal. Therefore, combining the driver inverter circuit and the driver circuit topology to quickly test the application characteristics of the device in the actual circuit, so as to quickly design the appropriate drive parameters, has become an urgent problem to be solved. Summary of the invention

[0005] The present application provides a motor driver drive circuit dynamic testing system, which can be used to solve the technical problem that standard dynamic and static testing equipment is only for a single device and is not universal.

[0006] The present application provides a motor driver drive circuit dynamic test system, the system comprising:

[0007] The dynamic test system includes: control module, drive module, power module, test fixture and data processing platform;

[0008] A control module, used to control the on and off of the power device under test and the on and off of various relays, and receive parameters and instructions sent by the data processing platform;

[0009] The drive module is used to realize various topologies and drive circuit forms of the inverter circuit. The common devices include: high-voltage capacitors, load inductors, and discharge relays. The independent sub-modules classified according to the device packaging include power supply terminals, different package power device drivers, power circuits, drive parameter debugging device replacement sockets, drive power supply sockets, and power output terminals;

[0010] The power module has a universal 24V DC input voltage and an output voltage for generating the drive module drive voltage and the control module supply voltage. Different drive voltages are used for the drive signals of different power devices, including IGBT, Si MOS, and SiC MOS. The jumpers of the transformer and feedback device circuit in the DC-DC circuit are realized through a plug-in interface to achieve fast switching.

[0011] The test fixture includes a heating fixture, various voltage and current test equipment, and structural parts that fix the equipment to the test points of the drive module;

[0012] The data processing platform is a data processing software used to process the voltage and current signals measured by the test equipment, send parameters and control instructions, and generate data reports and pictures; classify the voltage and current waveforms and identify key data.

[0013] Furthermore, the data processing platform, which runs on an industrial computer with an x86 CPU architecture, uses the Ethernet port to read the oscilloscope data and control the control module; the program is divided into three layers: bottom-level driver, middle-level calculation, and human-computer interface;

[0014] Among them, the bottom-level driver is used for oscilloscope driving, and the serial port toolkit is used to send instructions to the control module to collect data from the oscilloscope;

[0015] The middle-level calculation is used to implement the subroutines executed by each function, including data processing subroutines, parameter conversion subroutines, and file storage subroutines; the data processing subroutines are used to extract key waveforms from waveform data, obtain dynamic parameters, and convert the collected waveforms to obtain dynamic characteristic parameters; the parameter conversion subroutines are used to convert different setting conditions into test parameters; the file storage subroutines are used to convert the extracted dynamic parameters into data reports and pictures;

[0016] The human-computer interaction layer of the platform is a visual operation interface for functions including instrument control, relay control, parameter setting, and test data generation.

[0017] Furthermore, in the process of extracting effective data from the acquired waveform, the data processing platform needs to use the Grubbs criterion to eliminate data with abnormal numerical values ​​and the α-β-γ filter method to eliminate data with abnormal trends.

[0018] Furthermore, the Grubbs criterion was used to eliminate abnormal data of numerical size, including: recording the U obtained from the time period T0 to T2 for 30 tests P Value data sequence, denoted as data sequence X = [X1, X2, ..., X n ], n = 30; statistic G n It is expressed as:

[0019]

[0020] Where: represents the mean of the data sequence, σ represents the standard deviation of the data sequence; let the significance level be α, and we get:

[0021] P(G n ≥G(n,α))=α (2)

[0022] when When x n is an outlier and is removed. In the formula, G(n,α) is obtained by querying the Grubbs critical value table.

[0023] Furthermore, the α-β-γ filter performs prediction to remove data with abnormal trends, including:

[0024] Let the data sequence after removing the abnormal values ​​be Y=[Y1,Y2,…,Y n ], the predicted sequence is Re-estimate the third data point in the sequence as the initial value of the filter. The process is expressed as:

[0025]

[0026] Where: and is the filter intermediate variable;

[0027] Then perform recursive calculation, the process is expressed as:

[0028]

[0029] In formula (5), α, β and γ are filtering parameters, among which the empirical parameters are α = 0.2, β = 0.01486, γ = 0.0001842, Used to detect predicted values; when When , the data is considered to be abnormal data and is removed, and the threshold value M is adjusted according to the standard deviation of the sequence.

[0030] Furthermore, the high-voltage capacitor, load inductor, and discharge relay in the driver module share a common circuit, and the rest are divided into sub-modules of different regions according to the power device packaging;

[0031] The submodule includes a T0-247 device area, a T0-252 device area and a power module area; a power supply terminal is arranged near one side of the submodule, and a power output terminal is arranged near the other side; the positions of the power supply terminal, the power output terminal and the signal socket are the same in different submodules; a three-phase inverter circuit is arranged in the middle area of ​​the submodule, and one end (for example, the top) of the three-phase inverter circuit is a signal socket, and the signal socket is routed downward to the driver chip, and the driver chip gives a signal to the three-phase inverter circuit; each submodule is arranged horizontally.

[0032] Furthermore, the control module uses DSP as the main control core;

[0033] The control module includes a PWM signal conditioning circuit, a clock circuit, a reset circuit, an Ethernet communication circuit, and a USB debugging interface circuit; the control module receives control instructions and parameter information from the test system through the Ethernet communication circuit;

[0034] The USB debugging interface is used for testing in the debugging phase; based on the double-pulse test principle, the PWM signal conditioning circuit sends two-segment PWM signals through a pin connector to the input end of the upper and lower bridge arm driver chip of one phase in the three-phase inverter circuit of the drive module, and realizes the two-stage opening and closing of the corresponding power device through the driver chip.

[0035] Furthermore, the power module uses a flyback power topology to output 5V DC under the condition of 24V input power supply;

[0036] Connect to the control module power supply interface through a pin connector, and connect to different drive power supply sockets of the drive module through a pin connector. The voltage output includes: IGBT universal 15 / -9V, Si MOS universal 15V / 0V, SiC MOS universal 18 / -4V;

[0037] Set up a transformer base, replace transformers with different ratios, and perform jumpers on the corresponding feedback device circuits to achieve different power supply voltages for the rate device driver chip.

[0038] Furthermore, the test fixture uses a high-voltage differential probe to measure the voltage, and the current is measured using a Rogowski coil; the heating fixture platform can control the shell temperature of the power device, and is equipped with an adjustable telescopic bracket for fixing the probe and the Rogowski coil.

[0039] The motor driver drive circuit dynamic test device provided by the present invention can accurately measure actual dynamic parameters based on the circuit topology of the R&D product, thereby improving the debugging accuracy and debugging time of the driver drive circuit during the R&D process.

[0040] The data processing platform provided by the present invention can improve the efficiency, accuracy and intelligence of double pulse testing.

[0041] The driving circuit dynamic test device provided by the present invention can realize the test of various power device types and packages through multi-package area classification and pluggable base, thereby improving the utilization rate of power device dynamic test equipment and reducing equipment cost;

[0042] The data processing algorithm provided by the present invention can automatically identify key data of the voltage-current curve, and the obtained indicators are based on the actual PCB drive circuit layout, which can accurately obtain the performance and facilitate the rapid determination of the drive circuit parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 An overall diagram of the test device provided in an embodiment of the present application;

[0044] Figure 2 A schematic diagram of the distribution of drive modules provided in an embodiment of the present application;

[0045] Figure 3 A schematic diagram of a double pulse test based on board level provided in an embodiment of the present application;

[0046] Figure 4 A timing diagram of a double pulse waveform provided in an embodiment of the present application;

[0047] Figure 5 This is the software architecture diagram of the data processing platform. DETAILED DESCRIPTION

[0048] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0049] The following first introduces the embodiments of the present application in conjunction with the accompanying drawings.

[0050] The dynamic test system includes: control module, drive module, power module, test fixture and data processing platform.

[0051] The control module is used to control the on and off of the power device under test and the on and off of various relays, and receive parameters and instructions sent by the data processing platform.

[0052] The drive module is used to realize various topologies and drive circuit forms of the inverter circuit. The shared devices include: high-voltage capacitors, load inductors, and discharge relays. The independent sub-modules classified by device packaging include power supply terminals, different package power device drivers, power circuits, drive parameter debugging device replacement sockets, drive power supply sockets, and power output terminals. The independent sub-modules are designed according to the actual drive product drive, power circuit device layout, and PCB routing, and can be replaced.

[0053] The power module has a universal 24V DC input voltage and an output voltage for generating the drive module drive voltage and the control module supply voltage. Different drive voltages are used for the drive signals of different power devices, including IGBT, Si MOS, and SiC MOS. The jumpers of the transformer and feedback device circuit in the DC-DC circuit are quickly switched through the plug-in interface.

[0054] The test fixture includes a heating fixture, various voltage and current test equipment, and structural parts for fixing the equipment to the test points of the drive module.

[0055] The data processing platform refers to data processing software based on the x86 CPU architecture, which is used to process the voltage and current signals measured by the test equipment, send parameters and control instructions, and generate data reports and pictures. The host computer is developed through LabVIEW, and the relevant data processing functions are called through the Python language to classify the voltage and current waveforms and identify key data.

[0056] Each module is described in detail below.

[0057] The control module, with DSP as the main control core, constitutes the minimum system. The control module includes PWM signal conditioning circuit, clock circuit, reset circuit, Ethernet communication circuit, and USB debugging interface circuit; the control module receives control instructions, parameter information, etc. from the test system through the Ethernet communication circuit, and the USB debugging interface is used for testing in the debugging stage; based on the double pulse test principle, the PWM signal conditioning circuit sends two-segment PWM signals through a pin connector to the input end of the upper and lower bridge arm driver chip of one phase in the three-phase inverter circuit of the drive module, and realizes the two-segment opening and closing of the corresponding power device through the driver chip.

[0058] The power module uses a flyback power topology to output 5V DC under the condition of 24V input power supply;

[0059] Connect to the control module power supply interface through a pin connector, and connect to different drive power supply sockets of the drive module through a pin connector. The voltage output includes: IGBT universal 15 / -9V, Si MOS universal 15V / 0V, SiC MOS universal 18 / -4V. To achieve different power supply voltages for the power device driver chip, set the transformer base, replace transformers with different ratios, and jump the corresponding feedback device circuit.

[0060] The high-voltage capacitor, load inductor, and discharge relay in the drive module share the circuit, and the rest are divided into sub-modules in different areas according to the power device packaging. The sub-modules include the T0-247 device area, the T0-252 device area, and the power module area; Figure 2As shown, the overall size of the driver module substrate is 500*200mm. The submodules in different areas are fixed on the substrate by M3*20 hexagonal copper pillars around the periphery. The figure only shows the core components and the main PCB routing direction. The device layout of each submodule, the three-phase inverter circuit design, the drive circuit design, the current input and output routing are the same as the actual product design of the driver. The layout of each circuit and the PCB routing in the figure are only one way of existing products and can be modified according to different products. Each area is independent of each other to fully verify the performance of the drive circuit. The driver chip in the figure takes SOIC-16 as an example, and the actual module is not limited to the driver chip of this package. A power supply terminal is set near one side of the submodule, and a power output terminal is set near the other side; the side here is only a feasible position, which is adjusted according to needs; the positions of the power supply terminal, power output terminal, and signal socket in different submodules are the same; a three-phase inverter circuit is set in the middle area of ​​the submodule, and one end (for example, the top) of the three-phase inverter circuit is a signal socket, and the signal socket is routed downward to the driver chip, and the driver chip gives a signal to the three-phase inverter circuit; Figure 2 Each area is arranged horizontally;

[0061] Figure 2 The submodule can be updated according to the product design. Each submodule receives the drive signal of the control module and the supply voltage of the drive chip of the power module through the pin connector socket. The drive chip adopts a universal package to realize the opening of the drive signal of different types of power devices.

[0062] The test principle is based on double pulse testing, such as Figure 3 As shown in the figure, taking the A phase test in the three-phase inverter circuit as an example, Q1 and Q2 represent the upper and lower bridge arm MOSFETs or IGBTs in the driver circuit, L represents the load inductance, and C represents the high-voltage bus capacitance. The DS (CE), GS (GE) voltages, I D (I C ) The position of the current is also the same Figure 3 As shown in the figure, the measurement method of the lower bridge arm power device in the three-phase inverter circuit is shown. The upper bridge arm changes the load and the position of the measuring device accordingly. The drive signal and the corresponding DS (CE), GS (GE) voltage, I D (I C ) The current waveform is as follows Figure 4 shown.

[0063] In practical applications, the method provided by the embodiment of the present invention may also be applied to measuring stray capacitance in a power circuit during a turn-on process, but the present invention is not limited thereto.

[0064] The test fixture uses a high-voltage differential probe to measure voltage and a Rogowski coil to measure current for versatility. In order to examine the device characteristics at different temperatures, the heating fixture platform can control the shell temperature of the power device and is equipped with an adjustable telescopic bracket for fixing the probe and Rogowski coil.

[0065] The data processing platform runs on an industrial computer with an x86 CPU architecture, and uses the Ethernet port to read the oscilloscope data and control the control module; the program is divided into three layers: bottom-level driver, middle-level calculation, and human-computer interface. Figure 5 shown.

[0066] The underlying driver uses the VISA toolkit in LabVIEW to implement the oscilloscope driver, uses the serial port toolkit to send commands to the control module, and completes the oscilloscope data acquisition through the Wave Series toolkit.

[0067] The middle-level computing of the test platform is used to implement the subroutines executed by each function, including the data processing subroutine; the data processing subroutine is used to extract the key waveforms in the waveform data and obtain the dynamic parameters. The collected waveforms are processed according to the standards of IEC60747-8-2021 field effect transistors and IEC 60747-9-2019 insulated gate bipolar transistors, and converted to obtain dynamic characteristic parameters such as turn-off delay, rise time, turn-on delay, fall time, turn-on loss, turn-off loss, etc.; the parameter conversion subroutine is used to convert different setting conditions into test parameters; the file storage subroutine is used to convert the extracted dynamic parameters into data reports and pictures.

[0068] The human-computer interaction layer of the platform is a visual operation interface for functions including instrument control, relay control, parameter setting, and test data generation.

[0069] The core of the data processing platform is to extract effective data from the acquired waveform. The acquired waveform data format is two-dimensional data of voltage-time or current-time, and key parameters need to be identified from the saved waveform data.

[0070] According to the definition of IEC 60747-8-2021 and IEC 60747-9-2019, the key data include 10%, 90% GS (GE) cut-in voltage, 10%, 90% DS (CE) supply voltage, 2%, 10% I C (I D ) test current, DS (CE) maximum oscillation voltage, and the corresponding pin definition of IGBT is in brackets. Among them, GS (GE) turn-on voltage and DS (CE) supply voltage can be retrieved by test parameters in the corresponding time period to obtain accurate time coordinates. Figure 4 As shown in the test waveform, I C (ID ) Test current I T , DS(CE) maximum oscillation voltage U P Since it is necessary to obtain the maximum current or voltage value, affected by the test equipment noise, transmission interference, etc., the maximum current or voltage obtained may deviate from the normal value or normal trend. It is necessary to eliminate abnormal data and perform certain filtering calculations to obtain an accurate value.

[0071] The Grubbs criterion is used to eliminate data with abnormal numerical values, and the α-β-γ filter method is used to eliminate data with abnormal trends.

[0072] The Grubbs criterion is a method for detecting outliers in univariate data that follows a normal distribution and is applicable to data samples with a capacity between 20 and 100. During the implementation process, the distribution of the statistic is constructed and outliers are eliminated based on the preset significance level.

[0073] Comparison Figure 4 , record the U obtained during the time period from T0 to T2 for 30 tests P Value data sequence, denoted as data sequence X = [X1, X2, ..., X n ], n = 30; statistic G n It is expressed as:

[0074]

[0075] Where: represents the mean of the data sequence, σ represents the standard deviation of the data sequence; let the significance level be α, and we get:

[0076] P(G n ≥G(n,α))=α (2)

[0077] when When x n is an outlier and is removed. In the formula, G(n,α) is obtained by querying the Grubbs critical value table.

[0078] The α-β-γ filter algorithm uses filters for prediction and compares them with the measured data to eliminate abnormal trend data. Let the data sequence after eliminating abnormal values ​​be Y = [Y1, Y2, ..., Y n ], the predicted sequence is Re-evaluate the third data point in the sequence as the initial value of the filter. The calculation process is expressed as:

[0079]

[0080] Where: and is the filter intermediate variable;

[0081] Then perform recursive calculation, the process is expressed as:

[0082]

[0083] In formula (5), α, β and γ are filtering parameters, among which the empirical parameters are α = 0.2, β = 0.01486, γ = 0.0001842, Used to detect predicted values; when When , the data is considered to be abnormal data and is removed, and the threshold value M is adjusted according to the standard deviation of the sequence.

[0084] After removing the abnormal data, obtain the time coordinates corresponding to the data and continue the subsequent calculations.

[0085] The algorithm is finally implemented through Python voice design. The algorithm can accurately obtain key data, thereby obtaining indicators such as the power device's turn-on and turn-off time, turn-on and turn-off loss, and oscillation peak voltage.

[0086] The above-described embodiments of the present application do not constitute a limitation on the protection scope of the present application.

Claims

1. A motor driver drive circuit dynamic test system, characterized in that: The system comprises: The dynamic test system includes: control module, drive module, power module, test fixture and data processing platform; A control module, used to control the on and off of the power device under test and the on and off of various relays, and receive parameters and instructions sent by the data processing platform; The drive module is used to realize the topology and drive circuit form of the inverter circuit. The shared devices include: high-voltage capacitors, load inductors, and discharge relays. The independent sub-modules classified according to the device packaging include power supply terminals, different package power device drivers, power circuits, drive parameter debugging device replacement sockets, drive power supply sockets, and power output terminals. The power module has a universal 24V DC input voltage and an output voltage for generating the drive module drive voltage and the control module supply voltage. Different drive voltages are used for the drive signals of different power devices, including IGBT, Si MOS, and SiC MOS. The jumpers of the transformer and feedback device circuit in the DC-DC circuit are realized through a plug-in interface to achieve fast switching. The test fixture includes a heating fixture, a voltage and current test device, and a structural member for fixing the device to the test point of the drive module; The data processing platform is a data processing software used to process the voltage and current signals measured by the test equipment, send parameters and control instructions, and generate data reports and pictures; classify the voltage and current waveforms and identify key data.

2. The system according to claim 1, characterized in that The data processing platform runs on an industrial computer with an x86 CPU architecture and uses the Ethernet port to read the oscilloscope data and control the control module. The program is divided into three layers: bottom-level driver, middle-level calculation, and human-computer interface. Among them, the bottom-level driver is used for oscilloscope driving, and the serial port toolkit is used to send instructions to the control module to collect data from the oscilloscope; The middle-level calculation is used to implement the subroutines executed by each function, including data processing subroutines, parameter conversion subroutines, and file storage subroutines; the data processing subroutines are used to extract key waveforms from waveform data, obtain dynamic parameters, and convert the collected waveforms to obtain dynamic characteristic parameters; the parameter conversion subroutines are used to convert different setting conditions into test parameters; the file storage subroutines are used to convert the extracted dynamic parameters into data reports and pictures; The human-computer interaction layer of the platform is a visual operation interface for functions including instrument control, relay control, parameter setting, and test data generation.

3. The system according to claim 2, characterized in that In the process of extracting effective data from the acquired waveforms, the data processing platform needs to use the Grubbs criterion to eliminate data with abnormal numerical values ​​and the α-β-γ filter method to eliminate data with abnormal trends.

4. The system according to claim 3, characterized in that The Grubbs criterion was used to eliminate abnormal data of numerical size, including: recording the U obtained from T0 to T2 in 30 tests P Value data sequence, denoted as data sequence X = [X1, X2, ..., X n ], n = 30; statistic G n It is expressed as: Where: represents the mean of the data sequence, σ represents the standard deviation of the data sequence; let the significance level be α, and we get: P(G n ≥G(n,α))=α (2) when When x n is an outlier and is removed. In the formula, G(n,α) is obtained by querying the Grubbs critical value table.

5. The system according to claim 3, characterized in that The α-β-γ filter is used to predict and remove data with abnormal trends, including: Let the data sequence after removing the abnormal values ​​be Y=[Y1,Y2,…,Y n ], the predicted sequence is Re-estimate the third data point in the sequence as the initial value of the filter. The process is expressed as: Where: and is the filter intermediate variable; Then perform recursive calculation, the process is expressed as: In formula (5), α, β and γ are filtering parameters, among which the empirical parameters are α = 0.2, β = 0.01486, γ = 0.0001842, Used to detect predicted values; when When , the data is considered to be abnormal data and is removed, and the threshold value M is adjusted according to the standard deviation of the sequence.

6. The system according to claim 1, characterized in that The high-voltage capacitor, load inductor, and discharge relay in the drive module share the circuit, and the rest are divided into sub-modules in different areas according to the power device packaging; The submodule includes a T0-247 device area, a T0-252 device area and a power module area; a power supply terminal is arranged near one side of the submodule, and a power output terminal is arranged near the other side; the positions of the power supply terminal, the power output terminal and the signal socket are the same in different submodules; a three-phase inverter circuit is arranged in the middle area of ​​the submodule, and one end (for example, the top) of the three-phase inverter circuit is a signal socket, and the signal socket is routed downward to the driver chip, and the driver chip gives a signal to the three-phase inverter circuit; each submodule is arranged horizontally.

7. The system according to claim 1, characterized in that The control module uses DSP as the main control core; The control module includes a PWM signal conditioning circuit, a clock circuit, a reset circuit, an Ethernet communication circuit, and a USB debugging interface circuit; the control module receives control instructions and parameter information from the test system through the Ethernet communication circuit; The USB debugging interface is used for testing in the debugging phase; based on the double-pulse test principle, the PWM signal conditioning circuit sends two-segment PWM signals through a pin connector to the input end of the upper and lower bridge arm driver chip of one phase in the three-phase inverter circuit of the drive module, and realizes the two-stage opening and closing of the corresponding power device through the driver chip.

8. The system according to claim 1, characterized in that The power module uses a flyback power topology to output 5V DC under the condition of 24V input power supply; Connect to the control module power supply interface through a pin connector, and connect to different drive power supply sockets of the drive module through a pin connector. The voltage output includes: IGBT universal 15 / -9V, SiMOS universal 15V / 0V, SiC MOS universal 18 / -4V; Set up a transformer base, replace transformers with different ratios, and perform jumpers on the corresponding feedback device circuits to achieve different power supply voltages for the rate device driver chip.

9. The system according to claim 1, characterized in that The test fixture uses a high-voltage differential probe to measure voltage, and a Rogowski coil to measure current; the heating fixture platform can control the shell temperature of the power device, and is equipped with an adjustable telescopic bracket for fixing the probe and Rogowski coil.

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