IGBT aging status monitoring method and system for multi-phase half-bridge inverter

Abstract

The present invention relates to the technical field of IGBT state monitoring, and discloses an IGBT aging state monitoring method and system for a multi-phase half-bridge inverter. The method comprises measuring and calibrating the turn-off delay time and the inverter output voltage of the IGBT module respectively, and obtaining a calibration data comparison table; collecting the real-time output voltage of each phase of the inverter circuit under the current working condition; performing data processing on the real-time output voltage and the initial output voltage corresponding to the real-time output voltage under the current working condition respectively, and obtaining real-time aging characteristic parameters; determining the aging state of the IGBT module based on the calibration data comparison table and the real-time aging characteristic parameters. In the present invention, the real-time output voltage of the inverter circuit is used as the data for state monitoring, and the aging state of each internal IGBT module can be determined without invasive modification of the equipment circuit, so that the aging state of each IGBT module can be grasped in real time, and the operating conditions can be reasonably arranged or pre-maintenance can be performed.

Description

Technical Field

[0001] The present invention relates to the technical field of IGBT state monitoring, and in particular to an IGBT aging state monitoring method and system for a multi-phase half-bridge inverter. Background Art

[0002] With the rapid development of power electronics technology, PWM inverter technology with modern switching device IGBT as the core has been increasingly widely used in power systems. Inverters, as converters that realize DC / AC conversion of electric energy, are widely used in new energy power systems, such as electric vehicles, ship power systems, etc., and play a key role in modern power systems.

[0003] During the operation of the inverter, affected by factors such as electrical stress and environmental stress, the IGBT module will gradually age and fail, or even malfunction. IGBT failure may cause the output waveform of the equipment to be distorted, affecting the power quality of the power system, and may also cause chain failures, resulting in large-scale power outages in the power system. Therefore, it is of great significance to monitor the state of the IGBT in the inverter, monitor its aging state in real time, and predict and repair the device in advance to ensure the safe operation of the system. Most of the current state monitoring methods are device-level state monitoring methods for a single IGBT. For actual equipment applications, the current state monitoring methods have limitations such as strong circuit intrusion, high requirements for sensors, and high application costs. Therefore, how to achieve device-level IGBT state monitoring is an urgent problem to be solved in system state monitoring. Summary of the invention

[0004] The main purpose of the present invention is to provide an IGBT aging status monitoring method and system for a multi-phase half-bridge inverter, aiming to solve at least one of the problems of the prior art.

[0005] To achieve the above object, the present invention provides an IGBT aging status monitoring method for a multi-phase half-bridge inverter, comprising:

[0006] The turn-off delay time of the IGBT module and the inverter output voltage are measured and calibrated respectively to obtain a calibration data comparison table;

[0007] Collect the real-time output voltage of each phase of the inverter circuit under the current working conditions;

[0008] respectively performing data processing on the real-time output voltage and an initial output voltage corresponding to the real-time output voltage under the current working condition to obtain a real-time aging characteristic parameter;

[0009] The aging state of the IGBT module is determined based on the calibration data comparison table and the real-time aging characteristic parameters.

[0010] In some embodiments, the shut-off delay time of the IGBT module and the inverter output voltage are measured and calibrated respectively to obtain a calibration data comparison table, including:

[0011] Measuring the turn-off delay time of the IGBT module under a preset working condition and a preset aging condition in an offline state to establish a calibration time data comparison table of the IGBT module;

[0012] respectively measuring the initial output voltage of each phase of the inverter circuit under the preset working conditions;

[0013] Establishing a calibration voltage data comparison table according to the initial output voltage and the corresponding working conditions;

[0014] The calibration time data comparison table and the calibration voltage data comparison table are used as calibration data comparison tables.

[0015] In some embodiments, the off-line state measures the turn-off delay time of the IGBT module under a preset working condition and a preset aging state to establish a calibration time data comparison table of the IGBT module, including:

[0016] Measure the shutdown delay time of the IGBT module under preset working conditions and preset aging conditions in an offline state;

[0017] Determining an initial turn-off delay time of the IGBT module in an initial state;

[0018] Determining a difference between the measured turn-off delay time and the initial turn-off delay time;

[0019] A calibration time data comparison table of the IGBT module is established according to the difference.

[0020] In some embodiments, the collecting the real-time output voltage of each phase of the inverter circuit under the current working condition includes:

[0021] Set measuring points at the output terminals of the inverter circuit;

[0022] The real-time output voltage of each phase of the inverter circuit under the current working condition is collected based on the measuring point by a voltage sensor.

[0023] In some embodiments, the data processing of the real-time output voltage and the initial output voltage corresponding to the real-time output voltage under the current working condition to obtain the real-time aging characteristic parameter includes:

[0024] Determine an initial output voltage corresponding to the real-time output voltage under the current working condition;

[0025] Normalizing the real-time output voltage and the initial output voltage respectively to obtain normalized real-time voltage data and normalized initial voltage data;

[0026] Taking one switching cycle as the window width, respectively performing sliding average filtering and equally spaced sampling on the normalized real-time voltage data and the normalized initial voltage data to obtain filtered sampled real-time voltage data and filtered sampled initial voltage data;

[0027] A real-time aging characteristic parameter is obtained according to the filtered sampled real-time voltage data and the filtered sampled initial voltage data.

[0028] In some embodiments, obtaining the real-time aging characteristic parameter according to the filtered sampled real-time voltage data and the filtered sampled initial voltage data includes:

[0029] Obtain a turn-off delay time difference of the upper bridge arm switch tube according to a difference between a maximum value of the filtered sampled real-time voltage data and a maximum value of the filtered sampled initial voltage data;

[0030] Obtain a turn-off delay time difference of the lower bridge arm switch tube according to a difference between a minimum value of the filtered sampled real-time voltage data and a minimum value of the filtered sampled initial voltage data;

[0031] The turn-off delay time difference of the upper bridge arm switch tube and the turn-off delay time difference of the lower bridge arm switch tube are used as real-time aging characteristic parameters.

[0032] In some embodiments, determining the aging state of the IGBT module based on the calibration data comparison table and the real-time aging characteristic parameter includes:

[0033] Determine a turn-off delay time difference of each IGBT module according to the real-time aging characteristic parameter;

[0034] The aging state corresponding to the turn-off delay time difference of each IGBT module under the current working condition is searched according to the calibration data comparison table.

[0035] In addition, to achieve the above-mentioned purpose, the present invention also proposes an IGBT aging status monitoring system for a multi-phase half-bridge inverter, comprising:

[0036] A parameter calibration module is used to measure and calibrate the turn-off delay time of the IGBT module and the inverter output voltage respectively to obtain a calibration data comparison table;

[0037] A signal acquisition module is used to collect the real-time output voltage of each phase of the inverter circuit under the current working condition;

[0038] A data processing module, used to perform data processing on the real-time output voltage and an initial output voltage corresponding to the real-time output voltage under the current working condition to obtain a real-time aging characteristic parameter;

[0039] A state estimation module is used to determine the aging state of the IGBT module based on the calibration data comparison table and the real-time aging characteristic parameters.

[0040] In some embodiments, the parameter calibration module is specifically used to measure the turn-off delay time of the IGBT module under a preset working condition and a preset aging state in an offline state to establish a calibration time data comparison table of the IGBT module;

[0041] respectively measuring the initial output voltage of each phase of the inverter circuit under the preset working conditions;

[0042] Establishing a calibration voltage data comparison table according to the initial output voltage and the corresponding working conditions;

[0043] The calibration time data comparison table and the calibration voltage data comparison table are used as calibration data comparison tables.

[0044] In some embodiments, the signal acquisition module is specifically used to set a measurement point at the output terminal of the inverter circuit;

[0045] The real-time output voltage of each phase of the inverter circuit under the current working condition is collected based on the measuring point by a voltage sensor.

[0046] The present invention provides an IGBT aging state monitoring method for a multi-phase half-bridge inverter, comprising: measuring and calibrating the turn-off delay time of the IGBT module and the inverter output voltage respectively, obtaining a calibration data comparison table; collecting the real-time output voltage of each phase of the inverter circuit under the current working condition; performing data processing on the real-time output voltage and the initial output voltage corresponding to the real-time output voltage under the current working condition respectively, obtaining a real-time aging characteristic parameter; determining the aging state of the IGBT module based on the calibration data comparison table and the real-time aging characteristic parameter. In the present invention, the real-time output voltage of the inverter circuit is used as the data for state monitoring, and the aging state of each internal IGBT module can be determined without invasively modifying the device circuit, so that by monitoring the inverter state, the aging state of each IGBT module can be grasped in real time, and the operating conditions can be reasonably arranged or pre-maintenance can be performed, which solves the problems of strong circuit intrusion, high sensor requirements, and high application cost in the existing state monitoring method. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1It is a flow chart of an embodiment of an IGBT aging state monitoring method for a multi-phase half-bridge inverter according to the present invention;

[0048] Figure 2 A schematic diagram of an inverter topology structure and a sensor arrangement scheme involved in an embodiment of the present invention;

[0049] Figure 3 It is a schematic diagram of a specific implementation process involved in the embodiment of the present invention;

[0050] Figure 4 It is a structural block diagram of an embodiment of an IGBT aging status monitoring system for a multi-phase half-bridge inverter according to the present invention;

[0051] Figure 5 The present invention is a schematic diagram of the structure of an electronic device in a hardware operating environment according to an embodiment of the present invention.

[0052] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0055] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in the field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0056] The present invention provides an IGBT aging status monitoring method and system for a multi-phase half-bridge inverter.

[0057] The embodiment of the present invention provides an IGBT aging status monitoring method for a multi-phase half-bridge inverter, referring to Figure 1 , Figure 1 The figure is a flow chart of an embodiment of an IGBT aging status monitoring method for a multi-phase half-bridge inverter according to the present invention.

[0058] like Figure 1 As shown, the IGBT aging status monitoring method for a multi-phase half-bridge inverter includes:

[0059] Step S100: measuring and calibrating the turn-off delay time of the IGBT module and the inverter output voltage respectively to obtain a calibration data comparison table;

[0060] Step S200: collecting the real-time output voltage of each phase of the inverter circuit under the current working condition;

[0061] Step S300: performing data processing on the real-time output voltage and the initial output voltage corresponding to the real-time output voltage under the current working condition to obtain a real-time aging characteristic parameter;

[0062] Step S400: determining the aging state of the IGBT module based on the calibration data comparison table and the real-time aging characteristic parameters.

[0063] It should be noted that the execution subject in this embodiment may be an electronic device, which may be a computer device with data processing functions, or other devices that can achieve the same or similar functions. This embodiment does not limit this. In this embodiment, a computer device is used as an example for explanation.

[0064] It can be understood that the method described in the embodiment of the present invention can be used for IGBT aging status monitoring of a multi-phase half-bridge inverter, with the turn-off delay time of the IGBT module being used as a characteristic parameter to characterize the aging status of the IGBT module. By establishing an inverter state model containing the characteristic parameter (turn-off delay time), the aging status parameter of the IGBT is linked to the output voltage of the inverter, and the turn-off delay time change of each IGBT module inside the inverter is extracted through the output phase voltage of the inverter, thereby realizing real-time monitoring and evaluation of the aging status of the IGBT module.

[0065] Specifically, this embodiment is described by taking the evaluation of the aging state of each IGBT (insulated gate bipolar transistor) module in an inverter with a multi-phase half-bridge topology as an example. Figure 2 The inverter topology and sensor arrangement shown are described using a three-phase half-bridge topology as an example.

[0066] In some embodiments, the turn-off delay time of the IGBT module and the inverter output voltage are measured and calibrated respectively to obtain a calibration data comparison table, including: measuring the turn-off delay time of the IGBT module under preset operating conditions and preset aging conditions in an offline state to establish a calibration time data comparison table of the IGBT module; measuring the initial output voltage of each phase of the inverter circuit under preset operating conditions respectively; establishing a calibration voltage data comparison table according to the initial output voltage and the corresponding operating conditions; using the calibration time data comparison table and the calibration voltage data comparison table as the calibration data comparison table.

[0067] It should be noted that the implementation process of the IGBT aging status monitoring method for a multi-phase half-bridge inverter in this embodiment is as follows: Figure 3 As shown, the main links include parameter calibration link, signal acquisition link, data processing link, characteristic parameter calculation link and IGBT module state estimation link.

[0068] Exemplarily, the parameter calibration link includes IGBT parameter calibration and inverter output voltage calibration. A calibration time data comparison table is established through IGBT parameter calibration, and a calibration voltage data comparison table is established through inverter output voltage calibration. The calibration time data comparison table and the calibration voltage data comparison table are used as the calibration data comparison table.

[0069] In some embodiments, the shutdown delay time of the IGBT module under preset operating conditions and preset aging conditions is measured in an offline state to establish a calibration time data comparison table of the IGBT module, including: measuring the measured shutdown delay time of the IGBT module under preset operating conditions and preset aging conditions in an offline state; determining the initial shutdown delay time of the IGBT module in an initial state; determining the difference between the measured shutdown delay time and the initial shutdown delay time; and establishing a calibration time data comparison table of the IGBT module based on the difference.

[0070] Specifically, IGBT parameter calibration: measure the turn-off delay time t of the IGBT module under different working conditions and different aging conditions in the offline state. d-off , calculate the measured turn-off delay time t d-off The difference between the measured turn-off delay time and the initial turn-off delay time of the IGBT module in the initial state before aging is Δt d-off A mapping relationship between the calculated difference and the operating condition and aging state corresponding to the IGBT module is established, and a calibration time data comparison table of the IGBT module is established based on the mapping relationship.

[0071] Specifically, the inverter output voltage calibration is to measure the initial output voltage U of each phase (such as phase a, phase b and phase c) of the inverter circuit under different working conditions.xi (x=a,b,c) that is, the initial output voltage U of phase a is measured ai , initial output voltage U of phase b bi And the initial output voltage U of phase c ci , and establish a mapping relationship between the measured initial output voltage of each phase and the operating condition corresponding to the IGBT module, and establish a calibration voltage data comparison table of the IGBT module based on the mapping relationship.

[0072] It is understandable that the preset working condition and the preset aging state of the IGBT module need to be set according to the actual situation of the inverter application scenario, and this embodiment does not limit this.

[0073] In some embodiments, collecting the real-time output voltage of each phase of the inverter circuit under the current operating condition includes: setting a measuring point at the output terminal of the inverter circuit; and collecting the real-time output voltage of each phase of the inverter circuit under the current operating condition based on the measuring point by a voltage sensor.

[0074] It should be noted that the IGBT aging status monitoring method for a multi-phase half-bridge inverter in this embodiment is based on Figure 2 The three-phase half-bridge inverter topology and voltage measurement position shown in the figure are used to measure the output phase voltage at the inverter output terminal. Figure 2 As shown, the control system can output gate signals to the upper and lower bridge arms of each phase, wherein the a-phase half bridge includes the upper bridge arm switch tube S Ua and the lower bridge arm switch tube S La , the b-phase half bridge includes the upper bridge arm switch tube S Ub And the lower bridge arm switch tube S Lb ( Figure 2 The c-phase half bridge includes an upper arm switch tube S Uc And the lower bridge arm switch tube S Lc ( Figure 2 The output current of each phase (i a 、i b 、i c ) can be output to the impedance load Z, n represents the three-phase center point, Figure 2 Also shown is the DC power supply U s , DC voltage U dc And capacitor C.

[0075] For example, reference Figure 2 , set the measuring point (voltage measurement position) at the output terminal of the inverter circuit, and the voltage measurement position is located at the output end of each phase (such as Figure 2The dashed line shown connects the output end of each phase, and the voltage measurement position is connected to a voltage sensor to measure the real-time output voltage of each phase. It can be understood that the voltage sensor can be a voltage sensor outside or inside the device, and this embodiment is not limited to this.

[0076] Specifically, the signal acquisition link consists of: Figure 2 The measuring point shown measures the three-phase output phase voltage (the real-time output voltage of each phase), that is, the real-time output voltage U of phase a is measured. ar , real-time output voltage U of phase b br And the real-time output voltage U of phase c cr In this embodiment, a measuring point is set at the output terminal of the inverter circuit to measure the output voltage, and the inverter output voltage is used as the data for IGBT module status monitoring. The aging status of each internal IGBT module can be determined without invasively modifying the device circuit.

[0077] In some embodiments, data processing is performed on the real-time output voltage and the initial output voltage corresponding to the real-time output voltage under the current operating condition to obtain real-time aging characteristic parameters, including: determining the initial output voltage corresponding to the real-time output voltage under the current operating condition; normalizing the real-time output voltage and the initial output voltage to obtain normalized real-time voltage data and normalized initial voltage data; using a switching cycle as a window width, performing sliding average filtering and equally spaced sampling on the normalized real-time voltage data and the normalized initial voltage data to obtain filtered sampled real-time voltage data and filtered sampled initial voltage data; and obtaining real-time aging characteristic parameters based on the filtered sampled real-time voltage data and the filtered sampled initial voltage data.

[0078] It should be noted that Figure 3 The specific process of the data processing link is shown as an example. According to the specific process of the data processing link, the real-time output voltage U of the inverter is respectively xr (x=a,b,c) and the initial output voltage U corresponding to the working condition xi (x=a, b, c) to obtain the filtered sampled real-time voltage data U nf-xr And filter the sampled initial voltage data U nf-xi Here, the real-time output voltage U xr and the initial output voltage U xi The specific processing flow is basically the same. In this embodiment, the real-time output voltage U is processed by the data processing link. xr The specific processing flow of (x=a, b, c) is taken as an example to illustrate the initial output voltage U xi The processing flow of (x=a,b,c) can refer to the real-time output voltage Uxr The processing flow of (x=a,b,c) will not be repeated here.

[0079] Specifically, data processing:

[0080] (1) Normalize the measured output voltage:

[0081]

[0082] Among them, U n-x is the normalized real-time voltage data; U x is the real-time output voltage U xr (x=a,b,c);U th Here, the threshold voltage of the switch tube can be set according to actual conditions, such as 0 or (U dc ) / 2.

[0083] (2) The normalized data is filtered by sliding average with a switching cycle as the window width, and the data volume is reduced by sampling at equal intervals:

[0084]

[0085] Among them, ES(A, B) means sampling data A with equal intervals at intervals B, where data A is mean(U n-x , N s ), the spacing B is (10fs) / fsamp; mean(A', B') means that the data A' is filtered with B' as the window width, where A' is U n-x , B' is N s ;f s represents the switching frequency of the inverter, f samp represents the sampling frequency of the sensor. In one example, N s Indicates the number of sampling points of the window width, Figure 3 Medium T s Indicates the window width sampling time.

[0086] In some embodiments, real-time aging characteristic parameters are obtained based on the filtered sampled real-time voltage data and the filtered sampled initial voltage data, including: obtaining the turn-off delay time difference of the upper bridge arm switch tube based on the difference between the maximum value of the filtered sampled real-time voltage data and the maximum value of the filtered sampled initial voltage data; obtaining the turn-off delay time difference of the lower bridge arm switch tube based on the difference between the minimum value of the filtered sampled real-time voltage data and the minimum value of the filtered sampled initial voltage data; and using the turn-off delay time difference of the upper bridge arm switch tube and the turn-off delay time difference of the lower bridge arm switch tube as real-time aging characteristic parameters.

[0087] It should be noted that, according to the specific process of the above data processing link, the real-time output voltage of the inverter and the initial output voltage of the corresponding working condition are processed to obtain the filtered sampled real-time voltage data U nf-xr And filter the sampled initial voltage data U nf-xi According to the real-time voltage data U nf-xr And filter the sampled initial voltage data U nf-xi Calculate the characteristic parameters to obtain real-time aging characteristic parameters.

[0088] Specifically, characteristic parameter calculation link: calculate the real-time aging characteristic parameters corresponding to each IGBT module:

[0089] Δt d-offUx =max(U nf-xr )-max(U nf-xi )

[0090] Δt d-offLx =min(U nf-xr )-min(U nf-xi )

[0091] Among them, U nf-xr (x=a, b, c) is the filtered sampled real-time voltage data; U nf-xi (x=a, b, c) is the initial voltage data of the filtered sampling; Δt d-offUx The upper bridge arm switch S in the inverter Ux The corresponding real-time aging characteristic parameter, Δt d-offLx The lower bridge arm switch S in the inverter Lx Corresponding real-time aging characteristic parameters; where x = a, b, c.

[0092] For example, based on Figure 2 The three-phase half-bridge inverter topology shown in the figure is calculated in the characteristic parameter calculation link: the upper bridge arm switch tube S in phase a Ua The turn-off delay time difference is the real-time aging characteristic parameter Δt d-offUa , the lower bridge arm switch tube S in phase a La The turn-off delay time difference is the real-time aging characteristic parameter Δt d-offLa ; The upper arm switch tube S in phase b Ub The turn-off delay time difference is the real-time aging characteristic parameter Δt d-offUb , the lower bridge arm switch tube S in phase b Lb The turn-off delay time difference is the real-time aging characteristic parameter Δt d-offLb ; The upper arm switch tube S in phase c Uc The turn-off delay time difference is the real-time aging characteristic parameter Δt d-offUc , the lower bridge arm switch tube S in phase c LcThe turn-off delay time difference is the real-time aging characteristic parameter Δt d-offLc .

[0093] In some embodiments, the aging status of the IGBT module is determined based on the calibration data comparison table and the real-time aging characteristic parameters, including: determining the turn-off delay time difference of each IGBT module according to the real-time aging characteristic parameters; and searching the aging status corresponding to the turn-off delay time difference of each IGBT module under the current operating conditions according to the calibration data comparison table.

[0094] Specifically, in the IGBT module state estimation phase, the calculated real-time aging characteristic parameter Δt is converted into d-offUx and Δt d-offLx Compared with the Δt calibrated under the same working conditions d-off A comparison is performed to estimate the aging state of the corresponding IGBT module.

[0095] For example, based on Figure 2 The three-phase half-bridge inverter topology shown in the figure, IGBT module state estimation link: according to the calibration data comparison table and real-time aging characteristic parameter Δt d-offUa Estimate the upper bridge arm switch tube S in phase a Ua The aging state; according to the calibration data comparison table and the real-time aging characteristic parameter Δt d-offLa Estimate the lower bridge arm switch tube S in phase a La The aging state; according to the calibration data comparison table and the real-time aging characteristic parameter Δt d-offUb Estimate the upper bridge arm switch S in phase b Ub The aging state; according to the calibration data comparison table and the real-time aging characteristic parameter Δt d-offLb Estimate the lower bridge arm switch tube S in phase b Lb The aging state; according to the calibration data comparison table and the real-time aging characteristic parameter Δt d-offUc Estimate the upper bridge arm switch S in phase c Uc The aging state; according to the calibration data comparison table and the real-time aging characteristic parameter Δt d-offLc Estimate the lower bridge arm switch S in phase c Lc The aging status of all IGBT modules in the three-phase half-bridge inverter is determined by the aging status of the IGBT modules.

[0096] In the above-mentioned embodiment of the present invention, the inverter output phase voltage is used as the data source for status monitoring, and there is no need to perform invasive modification on the circuit. The turn-off delay time change during the aging process of the IGBT module is used as a characteristic parameter indicating its aging state, and the turn-off delay time parameter of each IGBT module can be extracted through the inverter output phase voltage data. The change in the turn-off delay time of the corresponding IGBT module is calculated by comparing the change in the peak and valley values ​​of each phase voltage with the calibrated value. By real-time monitoring of the inverter output phase voltage, the state estimation of each IGBT module can be completed once within a few fundamental wave cycles. The monitoring method is simple, rapid, and low in application cost, which improves the state monitoring efficiency of the IGBT module. In addition, by monitoring the status of each IGBT module of the inverter, the aging status of each IGBT can be grasped in real time, the operating conditions can be reasonably arranged or pre-maintenance can be performed, and the safety of power system operation can be improved.

[0097] It should be noted that the method described in the above embodiment of the present invention can be applied to the IGBT state monitoring of the inverter with a two-level half-bridge topology structure, and the turn-off delay time change of the IGBT module during the aging process is used as the characteristic parameter to characterize the aging state of the IGBT module, and the turn-off delay time of the IGBT module under different aging states and different working conditions is calibrated in an offline state. The inverter output phase voltage data is collected in real time and the data is processed, and the information related to the turn-off delay time of each IGBT module in the inverter is extracted therefrom. By comparing the real-time value of the characteristic information with the initial calibration value, the change in the turn-off delay time of each IGBT module relative to the initial state can be calculated as the characteristic value (real-time aging characteristic parameter) of the aging of the IGBT module in the inverter. By comparing the characteristic value with the calibration value in the offline state, the aging state of each IGBT module can be estimated.

[0098] The present embodiment provides an IGBT aging state monitoring method for a multi-phase half-bridge inverter, including: measuring and calibrating the turn-off delay time of the IGBT module and the inverter output voltage respectively, obtaining a calibration data comparison table; collecting the real-time output voltage of each phase of the inverter circuit under the current working condition; performing data processing on the real-time output voltage and the initial output voltage corresponding to the real-time output voltage under the current working condition respectively, obtaining a real-time aging characteristic parameter; determining the aging state of the IGBT module based on the calibration data comparison table and the real-time aging characteristic parameter. In the present embodiment, the real-time output voltage of the inverter circuit is used as the data for state monitoring, and the aging state of each internal IGBT module can be determined without invasively modifying the device circuit, so that by monitoring the inverter state, the aging state of each IGBT module can be grasped in real time, and the operating conditions can be reasonably arranged or pre-maintenance can be performed, which solves the problems of the existing state monitoring method, such as strong circuit intrusion, high sensor requirements, and high application cost.

[0099] In addition, an embodiment of the present invention also proposes a storage medium, on which is stored an IGBT aging status monitoring program for a multi-phase half-bridge inverter. When the IGBT aging status monitoring program for a multi-phase half-bridge inverter is executed by a processor, the steps of the IGBT aging status monitoring method for a multi-phase half-bridge inverter as described above are implemented.

[0100] Reference Figure 4 , Figure 4 The structure diagram of an embodiment of an IGBT aging status monitoring system for a multi-phase half-bridge inverter according to the present invention.

[0101] like Figure 4 As shown, the IGBT aging status monitoring system for a multi-phase half-bridge inverter includes:

[0102] The parameter calibration module 10 is used to measure and calibrate the turn-off delay time of the IGBT module and the inverter output voltage respectively to obtain a calibration data comparison table;

[0103] The signal acquisition module 20 is used to collect the real-time output voltage of each phase of the inverter circuit under the current working condition;

[0104] A data processing module 30, for performing data processing on the real-time output voltage and an initial output voltage corresponding to the real-time output voltage under the current working condition to obtain a real-time aging characteristic parameter;

[0105] The state estimation module 40 is used to determine the aging state of the IGBT module based on the calibration data comparison table and the real-time aging characteristic parameters.

[0106] In some embodiments, the parameter calibration module 10 is specifically used to measure the turn-off delay time of the IGBT module under a preset working condition and a preset aging state in an offline state to establish a calibration time data comparison table of the IGBT module;

[0107] respectively measuring the initial output voltage of each phase of the inverter circuit under the preset working conditions;

[0108] Establishing a calibration voltage data comparison table according to the initial output voltage and the corresponding working conditions;

[0109] The calibration time data comparison table and the calibration voltage data comparison table are used as calibration data comparison tables.

[0110] In some embodiments, the signal acquisition module 20 is specifically used to set a measurement point at the output terminal of the inverter circuit;

[0111] The real-time output voltage of each phase of the inverter circuit under the current working condition is collected based on the measuring point by a voltage sensor.

[0112] In this embodiment, the real-time output voltage of the inverter circuit is used as the data for status monitoring. The aging status of each internal IGBT module can be determined without invasively modifying the equipment circuit. Therefore, by monitoring the status of the inverter, the aging status of each IGBT module can be grasped in real time, and the operating conditions can be reasonably arranged or pre-maintenance can be performed, which solves the problems of existing status monitoring methods such as strong circuit intrusion, high requirements for sensors, and high application costs.

[0113] It should be noted that the technical details that are not described in detail in the embodiment of the IGBT aging status monitoring system for a multi-phase half-bridge inverter can be referred to the IGBT aging status monitoring method for a multi-phase half-bridge inverter as described above provided in any embodiment of the present invention, and will not be repeated here.

[0114] In addition, to achieve the above-mentioned objectives, the present invention also proposes an electronic device, which includes: a memory, a processor, and an IGBT aging status monitoring program for a multi-phase half-bridge inverter stored in the memory and executable on the processor, wherein the IGBT aging status monitoring program for a multi-phase half-bridge inverter is configured to implement the IGBT aging status monitoring method for a multi-phase half-bridge inverter as described above.

[0115] Reference Figure 5 , Figure 5 The figure is a schematic diagram of the structure of an electronic device of the hardware operating environment involved in the embodiment of the present invention.

[0116] like Figure 5As shown, the electronic device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Among them, the communication bus 1002 is used to realize the connection and communication between these components. The user interface 1003 may include a display screen (Display), an input unit such as a keyboard (Keyboard), and the optional user interface 1003 may also include a standard wired interface and a wireless interface. The network interface 1004 may optionally include a standard wired interface and a wireless interface (such as a wireless fidelity (Wireless-Fidelity, Wi-Fi) interface). The memory 1005 may be a high-speed random access memory (Random Access Memory, RAM memory) or a stable non-volatile memory (Non-Volatile Memory, NVM), such as a disk memory. The memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0117] Those skilled in the art will understand that Figure 5 The structure shown in the figure does not constitute a limitation on the electronic device, and may include more or less components than shown in the figure, or combine certain components, or arrange the components differently.

[0118] like Figure 5 As shown, the memory 1005 as a storage medium may include an operating system, a network communication module, a user interface module, and an IGBT aging status monitoring program for a multi-phase half-bridge inverter.

[0119] exist Figure 5 In the electronic device shown, the network interface 1004 is mainly used for data communication with a network server; the user interface 1003 is mainly used for data interaction with a user; the processor 1001 and the memory 1005 in the electronic device of the present invention can be set in the electronic device, and the electronic device calls the IGBT aging status monitoring program for a multi-phase half-bridge inverter stored in the memory 1005 through the processor 1001, and executes the IGBT aging status monitoring method for a multi-phase half-bridge inverter provided in an embodiment of the present invention.

[0120] It should be understood that the above is only an example and does not constitute any limitation on the technical solution of the present invention. In specific applications, technicians in this field can make settings as needed, and the present invention does not limit this.

[0121] It should be noted that the workflow described above is merely illustrative and does not limit the scope of protection of the present invention. In practical applications, technicians in this field can select part or all of them according to actual needs to achieve the purpose of the present embodiment, and no limitation is made here.

[0122] In addition, it should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0123] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0124] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as a read-only memory (ROM) / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present invention.

[0125] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for monitoring IGBT aging status of a multi-phase half-bridge inverter, characterized in that: include: The turn-off delay time of the IGBT module and the inverter output voltage are measured and calibrated respectively to obtain a calibration data comparison table; Collect the real-time output voltage of each phase of the inverter circuit under the current working conditions; respectively performing data processing on the real-time output voltage and an initial output voltage corresponding to the real-time output voltage under the current working condition to obtain a real-time aging characteristic parameter; Determining the aging state of the IGBT module based on the calibration data comparison table and the real-time aging characteristic parameters; Wherein, respectively processing the real-time output voltage and the initial output voltage corresponding to the real-time output voltage under the current working condition to obtain the real-time aging characteristic parameter includes: determining the initial output voltage corresponding to the real-time output voltage under the current working condition; respectively normalizing the real-time output voltage and the initial output voltage to obtain normalized real-time voltage data and normalized initial voltage data; taking one switching cycle as the window width, respectively performing sliding average filtering and equally spaced sampling on the normalized real-time voltage data and the normalized initial voltage data to obtain filtered sampled real-time voltage data and filtered sampled initial voltage data; obtaining the real-time aging characteristic parameter according to the filtered sampled real-time voltage data and the filtered sampled initial voltage data; A real-time aging characteristic parameter is obtained according to the filtered sampled real-time voltage data and the filtered sampled initial voltage data, including: obtaining a turn-off delay time difference of an upper bridge arm switch tube according to a difference between a maximum value of the filtered sampled real-time voltage data and a maximum value of the filtered sampled initial voltage data; obtaining a turn-off delay time difference of a lower bridge arm switch tube according to a difference between a minimum value of the filtered sampled real-time voltage data and a minimum value of the filtered sampled initial voltage data; and using the turn-off delay time difference of the upper bridge arm switch tube and the turn-off delay time difference of the lower bridge arm switch tube as real-time aging characteristic parameters.

2. The method according to claim 1, characterized in that The shutdown delay time of the IGBT module and the inverter output voltage are measured and calibrated respectively to obtain a calibration data comparison table, including: Measuring the turn-off delay time of the IGBT module under a preset working condition and a preset aging condition in an offline state to establish a calibration time data comparison table of the IGBT module; respectively measuring the initial output voltage of each phase of the inverter circuit under the preset working conditions; Establishing a calibration voltage data comparison table according to the initial output voltage and the corresponding working conditions; The calibration time data comparison table and the calibration voltage data comparison table are used as calibration data comparison tables.

3. The method according to claim 2, characterized in that The off-line state measures the turn-off delay time of the IGBT module under a preset working condition and a preset aging state to establish a calibration time data comparison table of the IGBT module, including: Measure the shutdown delay time of the IGBT module under preset working conditions and preset aging conditions in an offline state; Determining an initial turn-off delay time of the IGBT module in an initial state; Determining a difference between the measured turn-off delay time and the initial turn-off delay time; A calibration time data comparison table of the IGBT module is established according to the difference.

4. The method according to claim 1, characterized in that The real-time output voltage of each phase of the inverter circuit under the current working condition is collected, including: Set measuring points at the output terminals of the inverter circuit; The real-time output voltage of each phase of the inverter circuit under the current working condition is collected based on the measuring point by a voltage sensor.

5. The method according to any one of claims 1 to 4, characterized in that The determining the aging state of the IGBT module based on the calibration data comparison table and the real-time aging characteristic parameter includes: Determine a turn-off delay time difference of each IGBT module according to the real-time aging characteristic parameter; The aging state corresponding to the turn-off delay time difference of each IGBT module under the current working condition is searched according to the calibration data comparison table.

6. An IGBT aging status monitoring system for a multi-phase half-bridge inverter, characterized in that: include: A parameter calibration module is used to measure and calibrate the turn-off delay time of the IGBT module and the inverter output voltage respectively to obtain a calibration data comparison table; A signal acquisition module is used to collect the real-time output voltage of each phase of the inverter circuit under the current working condition; A data processing module, used to perform data processing on the real-time output voltage and an initial output voltage corresponding to the real-time output voltage under the current working condition to obtain a real-time aging characteristic parameter; A state estimation module, used to determine the aging state of the IGBT module based on the calibration data comparison table and the real-time aging characteristic parameters; Wherein, respectively processing the real-time output voltage and the initial output voltage corresponding to the real-time output voltage under the current working condition to obtain the real-time aging characteristic parameter includes: determining the initial output voltage corresponding to the real-time output voltage under the current working condition; respectively normalizing the real-time output voltage and the initial output voltage to obtain normalized real-time voltage data and normalized initial voltage data; taking one switching cycle as the window width, respectively performing sliding average filtering and equally spaced sampling on the normalized real-time voltage data and the normalized initial voltage data to obtain filtered sampled real-time voltage data and filtered sampled initial voltage data; obtaining the real-time aging characteristic parameter according to the filtered sampled real-time voltage data and the filtered sampled initial voltage data; A real-time aging characteristic parameter is obtained according to the filtered sampled real-time voltage data and the filtered sampled initial voltage data, including: obtaining a turn-off delay time difference of an upper bridge arm switch tube according to a difference between a maximum value of the filtered sampled real-time voltage data and a maximum value of the filtered sampled initial voltage data; obtaining a turn-off delay time difference of a lower bridge arm switch tube according to a difference between a minimum value of the filtered sampled real-time voltage data and a minimum value of the filtered sampled initial voltage data; and using the turn-off delay time difference of the upper bridge arm switch tube and the turn-off delay time difference of the lower bridge arm switch tube as real-time aging characteristic parameters.

7. The system according to claim 6, characterized in that The parameter calibration module is specifically used to measure the turn-off delay time of the IGBT module under a preset working condition and a preset aging state in an offline state, so as to establish a calibration time data comparison table of the IGBT module; respectively measuring the initial output voltage of each phase of the inverter circuit under the preset working conditions; Establishing a calibration voltage data comparison table according to the initial output voltage and the corresponding working conditions; The calibration time data comparison table and the calibration voltage data comparison table are used as calibration data comparison tables.

8. The system according to claim 6, characterized in that The signal acquisition module is specifically used to set a measurement point at the output terminal of the inverter circuit; The real-time output voltage of each phase of the inverter circuit under the current working condition is collected based on the measuring point by a voltage sensor.

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