CN115291590B - Online evaluation method, device, motor controller and medium for output current limitation - Google Patents
Online evaluation method, device, motor controller and medium for output current limitation Download PDFInfo
- Publication number
- CN115291590B CN115291590B CN202210922868.1A CN202210922868A CN115291590B CN 115291590 B CN115291590 B CN 115291590B CN 202210922868 A CN202210922868 A CN 202210922868A CN 115291590 B CN115291590 B CN 115291590B
- Authority
- CN
- China
- Prior art keywords
- motor controller
- output current
- real
- maximum output
- curve
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
- G05B23/00—Testing or monitoring of control systems or parts thereof
- G05B23/02—Electric testing or monitoring
- G05B23/0205—Electric testing or monitoring by means of a monitoring system capable of detecting and responding to faults
- G05B23/0208—Electric testing or monitoring by means of a monitoring system capable of detecting and responding to faults characterized by the configuration of the monitoring system
- G05B23/0213—Modular or universal configuration of the monitoring system, e.g. monitoring system having modules that may be combined to build monitoring program; monitoring system that can be applied to legacy systems; adaptable monitoring system; using different communication protocols
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P29/00—Arrangements for regulating or controlling electric motors, appropriate for both AC and DC motors
- H02P29/02—Providing protection against overload without automatic interruption of supply
- H02P29/032—Preventing damage to the motor, e.g. setting individual current limits for different drive conditions
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Automation & Control Theory (AREA)
- Control Of Electric Motors In General (AREA)
Abstract
The invention provides an online evaluation method, device, motor controller and medium of output current limit, relating to the technical field of motor controllers, comprising the steps of obtaining the flow rate and the temperature of real-time cooling liquid of a power module in the motor controller and obtaining real-time thermal resistance; the method comprises the steps of collecting power parameters of a motor controller, obtaining maximum output current allowed by a chip of a power module in the motor controller at the highest junction temperature, generating a first curve, generating a second curve according to voltage limitation of the power module in a switching-off transient state of a switch in the motor controller, generating a change curve of the chip junction temperature and the maximum output current as a target curve by using a minimum value envelope, collecting real-time chip junction temperature of the power module, obtaining corresponding maximum output current as an evaluation result according to the target curve, and solving the problem that the maximum current output capacity limitation set by the existing motor controller is not matched with the actual exertable output capacity, so that the motor controller cannot fully output.
Description
Technical Field
The present invention relates to the field of motor controllers, and in particular, to an online evaluation method and apparatus for output current limitation, a motor controller, and a medium.
Background
In the motor controller, in order to prevent the motor controller and the motor from being damaged due to excessive output current of the motor controller, the output current of the motor controller needs to be limited. The existing motor controller for the vehicle mostly adopts the maximum current output capacity under the worst working condition as the maximum current output limit under any working condition, but most of the situations are not in the worst working condition in the running process of the vehicle, and the current output capacity limit of the vehicle under the non-severe working condition is not matched with the current output capacity of the power module which can be fully exerted actually by the vehicle, so that the current output capacity of the power module cannot be fully exerted under the full working condition.
Disclosure of Invention
In order to overcome the technical defects, the invention aims to provide an online evaluation method and device of output current limitation, a motor controller and a medium, which are used for solving the problem that the motor controller cannot fully output due to mismatching of the maximum current output capability limitation set by the existing motor controller and the actual exertion output capability.
The invention discloses an online evaluation method of output current limit, comprising the following steps:
providing a first mapping table comprising a mapping relationship between the flow rate of the cooling liquid and the thermal resistance of the power module;
acquiring the real-time cooling liquid flow rate and the real-time cooling liquid temperature of a power module in a motor controller, and acquiring real-time thermal resistance according to the first mapping table;
collecting motor controller power parameters, wherein the motor controller power parameters comprise a power factor, a fundamental wave frequency, a switching frequency, a bus voltage and an output current;
obtaining maximum output current allowed by a chip of a power module in the motor controller at the highest junction temperature according to the power parameter, the real-time thermal resistance and the real-time cooling liquid temperature of the motor controller, and generating first curves corresponding to the maximum output current at different chip junction temperatures;
according to the voltage limit of the power module in the switching-off transient state of the switch in the motor controller, acquiring voltage stress changes when different chip junction temperatures of the power module in the motor controller correspond to the allowed maximum output current, and generating a second curve corresponding to the maximum output current;
based on the first curve and the second curve, the minimum value envelope is formed after the first curve and the second curve are overlapped, and a change curve of the junction temperature and the maximum output current of the chip is generated to serve as a target curve;
and acquiring the real-time chip junction temperature of the power module, and obtaining the corresponding maximum output current according to the target curve as an evaluation result.
Preferably, the obtaining the maximum output current allowed by the chip of the power module in the motor controller at the highest junction temperature includes:
calibrating conduction loss and switching loss of a plurality of sample chips at the highest junction temperature in advance;
Obtaining maximum output current allowed by the highest chip junction temperature of each sample by adopting circuit simulation or analytic calculation;
calculating the functional relation between the highest chip junction temperature of each sample and the maximum allowable output current, and generating a second mapping table;
And obtaining a corresponding allowable maximum output current based on the second mapping table by adopting the highest chip junction temperature of the power module in the calculation motor controller.
Preferably, the calculating the functional relation between the highest chip junction temperature of each sample and the allowed maximum output current, and generating the second mapping table, includes:
and establishing a functional relation according to the difference value of the highest chip junction temperature and the real-time cooling liquid temperature, which is consistent with the product of the power parameter of the motor controller and the real-time thermal resistance, and interpolating to generate a second mapping table.
Preferably, the step of obtaining voltage stress changes when different chip junction temperatures of the power module in the motor controller correspond to allowed maximum output currents according to voltage limits of the power module in a preset switch-off transient state in the motor controller, and generating a second curve corresponding to the maximum output currents by the different junction temperatures includes:
and controlling the dynamic switch of the motor controller, detecting the voltage of the power module in real time, drawing voltage change curves of the switches corresponding to the junction temperatures of a plurality of groups of chips in the turn-off transient state, and generating second curves corresponding to the maximum output currents of different junction temperatures. .
Preferably, before providing a first mapping table including a mapping relationship between a flow rate of the cooling fluid and a thermal resistance of the power module, the first mapping table includes:
And collecting a plurality of groups of cooling liquid flow rates and thermal resistances, and generating a first mapping table by adopting a finite element thermal-fluid coupling simulation experiment or a thermal resistance-cooling liquid flow rate relation curve calibrated by interpolation.
Preferably, the first curve, the second curve and the target curve are changed according to real-time thermal resistance and motor controller power parameters;
And a plurality of first curves, second curves or target curves corresponding to the real-time thermal resistance and the power parameters of the motor controller are stored in advance, and are obtained by matching the real-time thermal resistance corresponding to the junction temperature of the real-time chip and the power parameters of the motor controller.
The invention also provides an on-line evaluation device of the maximum output current of the motor controller, which comprises:
The system comprises a preprocessing module, a motor controller, a power factor acquisition module and a power factor acquisition module, wherein the preprocessing module is used for providing a first mapping table comprising a mapping relation between the flow rate of cooling liquid and the thermal resistance of the power module;
The first processing module is used for calculating the maximum output current allowed by a chip of the power module in the motor controller at the highest junction temperature according to the power parameter, the real-time thermal resistance and the real-time cooling liquid temperature of the motor controller, and generating a first curve corresponding to the maximum output current at different junction temperatures;
The second processing module is used for acquiring voltage stress changes when different chip junction temperatures of the power module in the motor controller correspond to the allowed maximum output currents according to the voltage limit of the power module in the motor controller under the switching-off transient state, and generating a second curve corresponding to the maximum output currents;
the third processing module is used for generating a change curve of the junction temperature and the maximum output current of the chip as a target curve by using a minimum value envelope after the first curve and the second curve are overlapped;
and the output module is used for acquiring the real-time chip junction temperature of the power module and obtaining the corresponding maximum output current as an evaluation result according to the target curve.
Preferably, the method further comprises:
the storage module is used for pre-storing a first mapping table, a second mapping table or a plurality of first curves, second curves or target curves corresponding to the real-time thermal resistance and the power parameters of the motor controller.
The present invention also provides a motor controller that,
Comprising a memory for storing executable program code, and
And a processor for invoking said executable program code in said memory, the executing steps comprising said evaluation method.
The present invention also provides a readable storage medium, having stored thereon a computer program,
The computer program when executed by a processor implements the steps of the evaluation method.
After the technical scheme is adopted, compared with the prior art, the method has the following beneficial effects:
According to the on-line evaluation method for the output current limitation of the motor controller, according to the maximum chip temperature and the allowable maximum output current obtained by presetting the voltage limitation of the power module in the motor controller under the switching-off transient state, the minimum values of the maximum output current and the allowable maximum output current are enveloped to obtain the maximum output current of the motor controller under the working condition, and meanwhile, the limitation of the voltage overshoot of the maximum chip junction temperature and the switching-off transient state on the output current is considered, so that the problem that the maximum current output capacity limitation set by the existing motor controller is not matched with the actual exertable output capacity, and the motor controller cannot fully output is solved.
Drawings
FIG. 1 is a flowchart of an embodiment of an on-line evaluation method of output current limitation according to the present invention;
FIG. 2 is a graph showing the relationship between thermal resistance and coolant flow rate under one condition in the first embodiment of the method for online evaluation of output current limitation according to the present invention;
FIG. 3 is a reference diagram of an off-voltage overshoot curve under different chip junction temperatures under one working condition in an embodiment of an on-line evaluation method for output current limitation according to the present invention;
FIG. 4 is a reference diagram of a second curve under a first working condition in an embodiment of an on-line evaluation method for output current limitation according to the present invention;
FIG. 5 is a reference diagram of a target curve under a first working condition in an on-line evaluation method of output current limitation according to an embodiment of the present invention;
fig. 6 is a schematic diagram of a second module of the online evaluation device for output current limitation according to the present invention.
Reference numerals:
7-on-line evaluation device of output current limitation, 71-preprocessing module, 72-first processing module, 73-second processing module, 74-third processing module, 75-output module, 76-storage module.
Detailed Description
Advantages of the invention are further illustrated in the following description, taken in conjunction with the accompanying drawings and detailed description.
Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The implementations described in the following exemplary examples are not representative of all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present disclosure as detailed in the accompanying claims.
The terminology used in the present disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used in this disclosure and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any or all possible combinations of one or more of the associated listed items.
It should be understood that although the terms first, second, third, etc. may be used in this disclosure to describe various information, these information should not be limited to these terms. These terms are only used to distinguish one type of information from another. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information, without departing from the scope of the present disclosure. The term "if" as used herein may be interpreted as "at..once" or "when..once" or "in response to a determination", depending on the context.
In the description of the present invention, it should be understood that the terms "longitudinal," "transverse," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, merely to facilitate describing the present invention and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.
In the description of the present invention, unless otherwise specified and defined, it should be noted that the terms "mounted," "connected," and "coupled" are to be construed broadly, and may be, for example, mechanical or electrical, or may be in communication with each other between two elements, directly or indirectly through intermediaries, as would be understood by those skilled in the art, in view of the specific meaning of the terms described above.
In the following description, suffixes such as "module", "component", or "unit" for representing elements are used only for facilitating the description of the present invention, and are not of specific significance per se. Thus, "module" and "component" may be used in combination.
The first embodiment provides an online evaluation method of output current limitation, which is used for online evaluation of maximum output current allowed by a motor controller under a real-time working condition, so that the maximum current output capacity limitation set by the motor controller is matched with the actual exertable output capacity, and the working efficiency is improved, and specifically referring to fig. 1, the method comprises the following steps:
Firstly, providing a first mapping table comprising a mapping relation between the flow rate of cooling liquid and thermal resistance of a power module;
It should be noted that the above-mentioned thermal resistance is the thermal resistance of the chip-coolant, and the motor controller is mainly determined by the coolant flow rate because the coolant component is fixed, so that the corresponding thermal resistance is obtained according to the coolant flow rate in the above-mentioned steps (as shown in fig. 2, a thermal resistance-coolant flow rate relation curve reference diagram), and the number and types of thermal resistances included in the actual chip are different due to different types of power modules set in different electric controls, which are not limited by examples, i.e. IGBT/FRD modules including IGBT chip thermal resistance, FRD chip thermal resistance and coupling thermal resistance between IGBT-FRD, and SiC MOSFET modules including only the thermal resistance of SiC MOSFET chips. The relative proportions of the thermal resistance parameters remain unchanged at different coolant flow rates. Therefore, the thermal resistance extraction strategy can be set to mainly extract the thermal resistance result of the IGBT/SiC MOSFET chip, and the remaining thermal resistances are converted according to the ratio obtained by the table lookup (i.e., the first mapping table).
The method comprises the steps of collecting a plurality of groups of cooling liquid flow rates and thermal resistances, and generating a first mapping table by adopting a finite element thermal-fluid coupling simulation experiment or interpolation calibrated thermal resistance-cooling liquid flow rate relation curve. In this embodiment, a plurality of sets of coolant flow rates and thermal resistances are obtained in advance, and a mapping relationship between the coolant flow rates and the thermal resistances is generated, for example, an actual measurement calibration or a simulation experiment can improve the accuracy of the mapping relationship, and the mapping relationship is obtained by directly looking up a table, so that the operation is convenient.
S100, acquiring the flow rate and the temperature of the real-time cooling liquid of a power module in a motor controller, and acquiring real-time thermal resistance according to the first mapping table;
In the above step, the real-time thermal resistance can be directly obtained according to the first mapping table, and additionally, the real-time cooling liquid flow rate and the real-time cooling liquid temperature can be measured by a method commonly used in the prior art, including but not limited to a method of directly obtaining by using a sensor or the like, or a disclosed method of collecting the cooling liquid flow rate or the temperature in real time.
S200, collecting power parameters of a motor controller, wherein the power parameters of the motor controller comprise a power factor, a fundamental wave frequency, a switching frequency, a bus voltage and an output current;
In this embodiment, the motor controller parameters are mainly determined by the operating conditions, and are specifically obtained by the above-mentioned prior art means, including but not limited to sensor acquisition, etc., power factor, fundamental frequency, switching frequency, bus voltage, and output current.
S300, obtaining maximum output current allowed by a chip of a power module in the motor controller at the highest junction temperature according to the power parameter, the real-time thermal resistance and the real-time cooling liquid temperature of the motor controller, and generating a first curve corresponding to the maximum output current at different chip junction temperatures;
The method comprises the steps of calibrating conduction loss and switching loss of a plurality of sample chips at the highest junction temperature in advance, obtaining allowed maximum output current corresponding to the highest chip junction temperature of each sample by adopting circuit simulation or analytic calculation, calculating the functional relation between the highest chip junction temperature of each sample and the allowed maximum output current to generate a second mapping table, obtaining corresponding allowed maximum output current based on the second mapping table by adopting the highest chip junction temperature of a power module in a calculation motor controller, and generating a first curve corresponding to the maximum output current of different chip junction temperatures.
In the above steps, the data may be tabulated according to a circuit simulation or a relational analysis calculation to generate a second mapping table according to a functional relation between the highest chip junction temperature of each sample and the allowed maximum output current according to a plurality of actual measurement values, and the corresponding allowed maximum output current may be obtained according to the highest chip junction temperature (the highest chip junction temperature is obtained in advance) of the power module in the motor controller.
Taking the junction temperature and the output current of the chip as unknown variables and the rest as known variables, specifically, calculating the functional relation between the highest junction temperature and the allowable maximum output current of each sample to generate a second mapping table, wherein the second mapping table comprises the following steps:
and establishing a functional relation according to the difference value of the chip junction temperature and the real-time cooling liquid temperature and the product of the power parameter of the motor controller and the real-time thermal resistance, and generating a second mapping table according to the highest chip junction temperature of each sample and the allowable maximum output current interpolation.
In the above step, the functional relationship may be expressed as:
t jmax is the highest chip junction temperature, T f is the cooling liquid temperature; For real-time thermal resistance, the maximum allowable module loss P loss is determined by the power parameters of the motor controller, namely, the power factor P, the fundamental wave frequency f AC, the switching frequency f SW and the bus voltage V DC, and the maximum output current I rms_maxTj of the current chip junction temperature, and the power factor P, the fundamental wave frequency f AC, the switching frequency f SW and the bus voltage V DC are obtained through the power parameters of the motor controller, so that the mapping relation between the chip junction temperature T jmax and the allowable maximum output current I rms_maxTj under the real-time thermal resistance can be obtained. T j is the junction temperature of the chip, I rms_max is the maximum output current, and I rms_maxTj is the maximum output current corresponding to the junction temperature of the chip. The second mapping table can be generated in the operation process by linear difference and other methods according to the highest chip junction temperature of each sample and the maximum allowable output current.
S400, obtaining voltage stress changes when different chip junction temperatures of the power module in the motor controller correspond to allowed maximum output currents according to voltage limitation of the power module in a preset switch-off transient state in the motor controller, and generating a second curve corresponding to the maximum output currents;
As an illustration, in the step S300, considering the limitation of the temperature (i.e. obtaining the allowable maximum output current corresponding to the highest chip temperature) to the maximum output current, in the step S400, considering the limitation of the voltage overshoot to the maximum output current in the switching off transient state in the motor controller, that is, except the limitation of the highest chip junction temperature to the voltage (or current) output capability, the voltage overshoot V ce_max of the switching off transient state of the power module is another important factor limiting the current output capability, and it is required to ensure that V ce_max is lower than the chip blocking voltage value under any working condition (i.e. the voltage limitation to the power module in the switching off transient state preset in the motor controller) to prevent the chip breakdown.
Specifically, according to the voltage limitation of the power module under the switching off transient state preset in the motor controller, the voltage stress change is obtained when the junction temperatures of different chips of the power module in the motor controller correspond to the allowed maximum output current, and a second curve corresponding to the maximum output current is generated, including:
And controlling the dynamic switch of the motor controller, detecting the voltage of the power module in real time, drawing voltage change curves of the switches corresponding to the junction temperatures of a plurality of groups of chips in the turn-off transient state, and generating second curves corresponding to the maximum output currents of different junction temperatures.
In this embodiment, referring to fig. 3, in the corresponding relationship curve of the off voltage overshoot at different chip junction temperatures under the multiple sets of bus voltages, the voltage overshoot of the power module in the switching off transient state of the switch is affected by factors such as the bus voltage of the motor controller, the output current, the chip junction temperature, etc., for example, when the load current is the same, V ce_max is inversely related to the chip junction temperature, that is, the higher the junction temperature is, the smaller the V ce_max is, and in addition, the higher the junction temperature is, the maximum voltage allowed by the chip body is also raised. Therefore, it can be considered that the higher the chip junction temperature is, the larger the output current is allowed at the same bus voltage;
based on the above, according to the test result of the dynamic switching process of the vehicle motor controller system, corresponding relation curves of the off voltage overshoots under different chip junction temperatures under multiple groups of bus voltages are drawn, so as to obtain voltage change curves under the switching off transient state corresponding to the multiple groups of chip junction temperatures, and tabulation is performed, in the electric control operation process, the change curve of the chip junction temperature-maximum output current (voltage stress curve of the maximum current) is obtained by checking the bus voltages in real time and adopting a linear difference value and other methods, and is used as one of the limiting values of the current output capability, namely the second curve (refer to fig. 4).
S500, generating a change curve of the junction temperature of the chip and the allowable maximum output current as a target curve based on the minimum envelope after the first curve and the second curve are overlapped;
Specifically, the maximum output current allowed by the highest junction temperature of the chip is overlapped with the voltage stress curve of the maximum current, and the minimum value envelope is taken, namely the maximum output current allowed by the electric control under different junction temperatures (namely, the voltage overshoot of the highest junction temperature and the turn-off transient is considered at the same time), and referring to fig. 5, the maximum junction temperature limiting current and the voltage overshoot limiting current curve are overlapped to be the maximum allowed current output value under different junction temperatures, wherein a straight line parallel to the X axis and positioned at the position of I rms_maxTj is a first curve obtained under the working condition, the trend of the straight line in fig. 4 is similar to a second curve under the working condition, and the minimum value in the two curves is enveloped as shown in the figure, so that I rms_max corresponding to T j can be obtained. It should be specifically noted that the relative positions of the two curves under different motor working conditions (i.e. different real-time thermal resistances and power parameters of the motor controller) are continuously changed, the drawn envelope curves are also changed, and the two curves may not overlap. Therefore, in order to be suitable for quickly obtaining the allowable maximum output current under different working conditions, a plurality of first curves, second curves or target curves corresponding to the real-time thermal resistance and the motor controller power parameters can be stored in advance, and the target curves are obtained according to the matching of the real-time thermal resistance corresponding to the junction temperature of the real-time chip and the motor controller power parameters, namely, target curves under a plurality of working conditions are preset, and a table is directly checked and obtained under the application of actual working conditions.
And S600, acquiring the real-time chip junction temperature of the power module, and obtaining the corresponding maximum output current according to the target curve as an evaluation result.
In the above steps, the real-time chip junction temperature of the power module is acquired by adopting an acquisition mode disclosed in the prior art, and it is to be noted that, unlike the application of the chip junction temperature acquired in the prior art, the method is used for calculating the maximum output current allowed under the working condition, and as an example, the chip junction temperature can be monitored in real time by methods of on-line junction temperature extraction, NTC indirect calibration test and the like of the chip, and the real-time maximum output current value allowed under the real-time chip junction temperature can be determined.
In this embodiment, the problem that the current output capability of the power module cannot be fully exerted by the electric vehicle under the full working condition due to the fact that the current output capability of the existing vehicle motor controller under the worst working condition is used as the current output limit under any working condition is solved, and according to the maximum output current obtained by obtaining the highest chip temperature and the voltage limit of the power module under the switching off transient state preset in the motor controller, the limitation of the highest chip junction temperature and the voltage overshoot of the switching off transient state on the output current is considered, the thermal stress and the voltage stress current output limit of the power module are comprehensively considered, the analysis error caused by single-dimension analysis is reduced, and the evaluation result is more accurate.
Second embodiment the present embodiment provides an on-line evaluation device 7 for output current limitation, referring to fig. 6, for a motor controller, comprising:
The preprocessing module 71 is used for providing a first mapping table comprising a mapping relation between the flow rate of the cooling liquid and the thermal resistance of the power module, acquiring the flow rate of the real-time cooling liquid and the temperature of the real-time cooling liquid of the power module in the motor controller, and acquiring the power parameters of the motor controller according to the first mapping table, wherein the power parameters of the motor controller comprise a power factor, a fundamental wave frequency, a switching frequency, a bus voltage and an output current;
Specifically, the real-time thermal resistance can be directly obtained according to the first mapping table, the parameters of the motor controller are mainly determined by the operation conditions, and as a supplement, the flow rate of the real-time cooling liquid, the temperature of the real-time cooling liquid and the parameters of the motor controller can be measured by a common method in the prior art.
The first processing module 72 is configured to obtain a maximum output current allowed by a chip of the power module in the motor controller at a highest junction temperature according to the power parameter, the real-time thermal resistance and the real-time coolant temperature of the motor controller, and generate a first curve corresponding to the maximum output current for different chip junction temperatures;
Specifically, a functional relation is established according to the difference value between the junction temperature of the chip and the temperature of the real-time cooling liquid relative to the product of the power parameter of the motor controller and the real-time thermal resistance, so as to obtain the maximum output current allowed by the chip at the highest junction temperature, wherein the first curve is positioned on an X axis with different junction temperatures of the chip, and the maximum output current is represented as a straight line parallel to the X axis and corresponding to the maximum output current allowed by the highest junction temperature of the chip on the Y axis in the coordinates of the Y axis.
The second processing module 73 is configured to obtain voltage stress changes when different chip junction temperatures of the power module in the motor controller correspond to allowed maximum output currents according to a preset voltage limit on the power module in a switching-off transient state of the motor controller, and generate a second curve corresponding to the maximum output currents;
Specifically, the motor controller is controlled to dynamically switch, the voltage of the power module is detected in real time, and voltage change curves under the switching-off transient state of the switches corresponding to the junction temperatures of the plurality of groups of chips are drawn, so that a second curve can be generated.
A third processing module 74, configured to generate a change curve of the chip junction temperature and the allowable maximum output current as a target curve based on the first curve and the second curve, which are superimposed and enveloped by a minimum value;
In the above modules, the maximum output current allowed by the electrical control (i.e. the voltage overshoot taking into account both the highest chip junction temperature and the off-transients) at different junction temperatures is obtained. It should be specifically noted that the relative positions of the two curves under different motor conditions (i.e., different real-time thermal resistances and motor controller power parameters) will change continuously.
And the output module 75 is used for acquiring the real-time chip junction temperature of the power module and obtaining the corresponding maximum output current according to the target curve as an evaluation result.
Specifically, in the above steps, the method disclosed in the prior art, such as online junction temperature extraction, NTC indirect calibration test, etc., is adopted to collect the real-time chip junction temperature of the power module.
Specifically, the evaluation device may further include:
The storage module 76 is configured to pre-store the first mapping table, the second mapping table, or a plurality of first curves, second curves, or target curves corresponding to the real-time thermal resistance and the power parameter of the motor controller.
The first curve, the second curve and the target curve are considered to change according to the real-time thermal resistance and the power parameter of the motor controller, a plurality of corresponding first curves, second curves or target curves under the real-time thermal resistance and the power parameter of the motor controller can be stored in advance, and are obtained according to the matching of the real-time thermal resistance corresponding to the junction temperature of the real-time chip and the power parameter of the motor controller, namely, target curves under a plurality of working conditions are preset, a list is obtained, and the maximum output current obtaining efficiency under an actual scene is improved by directly looking up and obtaining under the application of the actual working conditions.
In this embodiment, the first processing module and the second processing module are adopted to obtain the highest chip temperature and the allowed maximum output current obtained by presetting the voltage limitation of the power module in the motor controller under the switching-off transient state, and the third processing module is adopted to obtain the minimum values of the two, which includes, simultaneously, considering the limitation of the highest chip junction temperature and the voltage overshoot of the switching-off transient state on the output current, so that the maximum current output capacity limitation of the estimated motor controller is matched with the practically exertable output capacity, the operation efficiency of the motor controller is improved, the limitation on the output capacity is considered in a multi-dimensional manner, and the accuracy of the estimation result is improved.
Embodiment III:
To achieve the above object, the present invention also provides a motor controller capable of executing the program code in the first embodiment. The computer device of the present embodiment includes at least, but is not limited to, a memory and a processor that can be communicatively coupled to each other via a device bus. It should be noted that only a device having components is shown, but it should be understood that not all of the illustrated components are required to be implemented and that more or fewer components may be implemented instead.
In this embodiment, the memory may be an internal storage unit of the motor controller or may be an external storage device of the motor controller, and in this embodiment, the memory is generally used to store operating devices or data installed in the motor controller, for example, program codes and data (such as a motor controller power parameter, a first mapping table, and a second mapping table) of an online evaluation method of a maximum output current of the motor controller in the first embodiment. In addition, the memory may be used to temporarily store various types of data (e.g., data corresponding to a target curve, etc.) to be output or to be output.
The processor is typically used to control the overall operation of the motor controller. In this embodiment, the processor is configured to execute the program code stored in the memory or process data, for example, to execute the online evaluation method of the output current limit of the first embodiment.
Embodiment four:
To achieve the above object, the present invention also provides a readable storage device having stored thereon a computer program which when executed by a processor realizes corresponding functions. The computer-readable storage medium of the present embodiment is used for storing data, and when executed by a processor, implements the on-line evaluation method of the output current limit of the first embodiment and the on-line evaluation apparatus of the output current limit of the second embodiment.
It should be noted that the embodiments of the present invention are preferred and not limited in any way, and any person skilled in the art may make use of the above-disclosed technical content to change or modify the same into equivalent effective embodiments without departing from the technical scope of the present invention, and any modification or equivalent change and modification of the above-described embodiments according to the technical substance of the present invention still falls within the scope of the technical scope of the present invention.
Claims (7)
1. An on-line evaluation method of output current limitation, characterized by comprising:
providing a first mapping table comprising a mapping relationship between the flow rate of the cooling liquid and the thermal resistance of the power module;
acquiring the real-time cooling liquid flow rate and the real-time cooling liquid temperature of a power module in a motor controller, and acquiring real-time thermal resistance according to the first mapping table;
collecting motor controller power parameters, wherein the motor controller power parameters comprise a power factor, a fundamental wave frequency, a switching frequency, a bus voltage and an output current;
obtaining maximum output current allowed by a chip of a power module in the motor controller at the highest junction temperature according to the power parameter, the real-time thermal resistance and the real-time cooling liquid temperature of the motor controller, and generating first curves corresponding to the maximum output current at different chip junction temperatures;
according to the voltage limit of the power module in the switching-off transient state of the switch in the motor controller, acquiring voltage stress changes when different chip junction temperatures of the power module in the motor controller correspond to the allowed maximum output current, and generating a second curve corresponding to the maximum output current;
based on the first curve and the second curve, the minimum value envelope is formed after the first curve and the second curve are overlapped, and a change curve of the junction temperature and the maximum output current of the chip is generated to serve as a target curve;
collecting the real-time chip junction temperature of the power module, and obtaining corresponding maximum output current as an evaluation result according to the target curve, wherein
The obtaining the maximum output current allowed by the chip of the power module in the motor controller at the highest junction temperature comprises the following steps:
calibrating conduction loss and switching loss of a plurality of sample chips at the highest junction temperature in advance;
Obtaining maximum output current allowed by the highest chip junction temperature of each sample by adopting circuit simulation or analytic calculation;
calculating the functional relation between the highest chip junction temperature of each sample and the maximum allowable output current, and generating a second mapping table;
Based on the second mapping table, adopting the highest chip junction temperature of the power module in the motor controller to obtain a corresponding allowed maximum output current;
And calculating the functional relation between the highest chip junction temperature of each sample and the allowable maximum output current, and generating a second mapping table, wherein the second mapping table comprises the following components:
Establishing a functional relation according to the difference value of the highest chip junction temperature and the real-time cooling liquid temperature, which is consistent with the product of the power parameter of the motor controller and the real-time thermal resistance, and interpolating to generate a second mapping table;
According to the voltage limitation of the power module under the switching-off transient state of the switch in the motor controller, the voltage stress change is obtained when the junction temperature of different chips of the power module in the motor controller corresponds to the allowed maximum output current, and a second curve corresponding to the maximum output current with different junction temperatures is generated, and the method comprises the following steps:
And controlling the dynamic switch of the motor controller, detecting the voltage of the power module in real time, drawing voltage change curves of the switches corresponding to the junction temperatures of a plurality of groups of chips in the turn-off transient state, and generating second curves corresponding to the maximum output currents of different junction temperatures.
2. The online evaluation method according to claim 1, before providing a first map including a mapping relationship between a flow rate of the coolant and a thermal resistance of the power module, comprising:
And collecting a plurality of groups of cooling liquid flow rates and thermal resistances, and generating a first mapping table by adopting a finite element thermal-fluid coupling simulation experiment or a thermal resistance-cooling liquid flow rate relation curve calibrated by interpolation.
3. The online assessment method according to claim 1, comprising:
the first curve, the second curve and the target curve are changed according to the real-time thermal resistance and the power parameters of the motor controller;
And a plurality of first curves, second curves or target curves corresponding to the real-time thermal resistance and the power parameters of the motor controller are stored in advance, and are obtained by matching the real-time thermal resistance corresponding to the junction temperature of the real-time chip and the power parameters of the motor controller.
4. An on-line evaluation device for output current limitation, characterized by comprising:
The system comprises a preprocessing module, a motor controller, a power factor acquisition module and a power factor acquisition module, wherein the preprocessing module is used for providing a first mapping table comprising a mapping relation between the flow rate of cooling liquid and the thermal resistance of the power module;
The first processing module is used for calculating the maximum output current allowed by a chip of the power module in the motor controller at the highest junction temperature according to the power parameter, the real-time thermal resistance and the real-time cooling liquid temperature of the motor controller, and generating a first curve corresponding to the maximum output current at different junction temperatures;
The second processing module is used for acquiring voltage stress changes when different chip junction temperatures of the power module in the motor controller correspond to the allowed maximum output currents according to the voltage limit of the power module in the motor controller under the switching-off transient state, and generating a second curve corresponding to the maximum output currents;
the third processing module is used for generating a change curve of the junction temperature and the maximum output current of the chip as a target curve by using a minimum value envelope after the first curve and the second curve are overlapped;
The output module is used for collecting the real-time chip junction temperature of the power module, and obtaining the corresponding maximum output current as an evaluation result according to the target curve, wherein the maximum output current is obtained by the output module
The first processing module acquires the maximum output current allowed by the highest chip junction temperature of each sample by adopting circuit simulation or analytic calculation; based on the second mapping table, adopting the highest chip junction temperature of a power module in the motor controller to obtain corresponding allowable maximum output current;
the first processing module builds a functional relation according to the difference value of the highest chip junction temperature and the real-time cooling liquid temperature and the product of the power parameter of the motor controller and the real-time thermal resistance, and interpolates to generate a second mapping table;
The second processing module controls the dynamic switch of the motor controller, detects the voltage of the power module in real time, draws voltage change curves under the switching-off transient state of the switches corresponding to the junction temperatures of the plurality of groups of chips, and generates second curves corresponding to the maximum output currents of different junction temperatures.
5. The online assessment device of claim 4, further comprising:
the storage module is used for pre-storing a first mapping table, a second mapping table or a plurality of first curves, second curves or target curves corresponding to the real-time thermal resistance and the power parameters of the motor controller.
6. A motor controller, characterized by:
Comprising a memory for storing executable program code, and
A processor for invoking said executable program code in said memory, the executing step comprising the online assessment method of any of claims 1 to 3.
7. A computer-readable storage medium having stored thereon a computer program, characterized by:
The computer program, when executed by a processor, implements the steps of the online assessment method of any one of claims 1 to 3.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210922868.1A CN115291590B (en) | 2022-08-02 | 2022-08-02 | Online evaluation method, device, motor controller and medium for output current limitation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210922868.1A CN115291590B (en) | 2022-08-02 | 2022-08-02 | Online evaluation method, device, motor controller and medium for output current limitation |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115291590A CN115291590A (en) | 2022-11-04 |
| CN115291590B true CN115291590B (en) | 2025-01-28 |
Family
ID=83826395
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210922868.1A Active CN115291590B (en) | 2022-08-02 | 2022-08-02 | Online evaluation method, device, motor controller and medium for output current limitation |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115291590B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118899806A (en) * | 2024-10-09 | 2024-11-05 | 潍柴动力股份有限公司 | A power module protection method, device, equipment and storage medium |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105790677A (en) * | 2016-04-15 | 2016-07-20 | 郑州宇通客车股份有限公司 | Motor controller overload protection method and system |
| CN109597966A (en) * | 2018-11-30 | 2019-04-09 | 上海大郡动力控制技术有限公司 | The evaluation method of power component IGBT junction temperature in electric machine controller |
Family Cites Families (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008131722A (en) * | 2006-11-20 | 2008-06-05 | Nippon Reliance Kk | Power element overheating protection device |
| CN107219016B (en) * | 2017-05-24 | 2019-05-17 | 湖南大学 | Calculate the method and system of IGBT module transient state junction temperature |
| CN108072821B (en) * | 2017-12-06 | 2018-11-16 | 南京埃斯顿自动控制技术有限公司 | The real-time online prediction technique of semiconductor power device dynamic junction temperature |
| JP6786012B1 (en) * | 2019-11-29 | 2020-11-18 | 三菱電機株式会社 | Power converter |
| CN113030683A (en) * | 2021-03-15 | 2021-06-25 | 五羊—本田摩托（广州）有限公司 | Method, medium and computer equipment for measuring temperature of power switch device |
| CN113708702B (en) * | 2021-09-01 | 2023-08-22 | 臻驱科技（上海）有限公司 | A frequency reduction control method and system for a motor controller |
| CN114595654B (en) * | 2021-12-28 | 2024-08-13 | 臻驱科技（上海）有限公司 | Dynamic characteristic utilization method during switching of power device |
| CN114674451A (en) * | 2022-03-10 | 2022-06-28 | 极氪汽车(宁波杭州湾新区)有限公司 | Method for estimating cooling liquid temperature of vehicle motor controller, motor controller and vehicle |
-
2022
- 2022-08-02 CN CN202210922868.1A patent/CN115291590B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105790677A (en) * | 2016-04-15 | 2016-07-20 | 郑州宇通客车股份有限公司 | Motor controller overload protection method and system |
| CN109597966A (en) * | 2018-11-30 | 2019-04-09 | 上海大郡动力控制技术有限公司 | The evaluation method of power component IGBT junction temperature in electric machine controller |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115291590A (en) | 2022-11-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101093472B1 (en) | Devices for controlling electric motors | |
| CN109597966B (en) | Method for estimating junction temperature of IGBT (insulated Gate Bipolar transistor) of power element in motor controller | |
| US7859207B2 (en) | Method and apparatus for controlling electric motor | |
| EP3118638B1 (en) | Temperature estimation in power semiconductor device in electric drive system | |
| CN115291590B (en) | Online evaluation method, device, motor controller and medium for output current limitation | |
| CN108072821A (en) | The real-time online Forecasting Methodology of semiconductor power device dynamic junction temperature | |
| US9995636B2 (en) | Temperature sensing system for switching device | |
| CN109490739A (en) | The method and module of estimation on line are carried out to the junction temperature of IGBT module | |
| WO2021124707A1 (en) | Method for estimating parameters of a junction of a power semi-conductor element and power unit | |
| CN111090017A (en) | Method for estimating service life of capacitor of frequency converter | |
| CN113030682A (en) | High-precision junction temperature online monitoring method and system | |
| CN113949327A (en) | Power module for operating an electric vehicle drive | |
| CN115122947B (en) | IGBT temperature estimation method, motor torque control method and device of electric automobile, equipment and medium | |
| CN104303063A (en) | Method and device for determining a temperature calibration characteristic curve of a semiconductor device of a power electronic device | |
| CN105074446A (en) | Lambda sensor preheating control method and lambda sensor driving control device | |
| US9719860B2 (en) | Power device temperature monitor | |
| CN107305146B (en) | Parameter determination device for estimating temperature of switching element of inverter | |
| CN116754912A (en) | Temperature control method for IGBT test | |
| CN116702601A (en) | Method and device for estimating junction temperature of vehicle power module, electronic equipment and storage medium | |
| US20040135586A1 (en) | Resistive load measurement system | |
| CN112594050A (en) | Method and apparatus for controlling propulsion system warm-up based on engine wall temperature | |
| CN112556868A (en) | SiC MOSFET junction temperature detection method based on combined thermosensitive electrical parameter sensitivity enhancement | |
| CN112765786A (en) | Junction temperature estimation method for power device, motor controller, and computer-readable storage medium | |
| CN119720501A (en) | Method and device for estimating junction temperature of power device through thermal resistance parameter compensation | |
| JP7241349B2 (en) | Transient thermal characteristic analysis device, analysis method and program |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information | ||
| CB02 | Change of applicant information |
Country or region after: China Address after: 201203 3rd floor, building 19, building 8, No. 498, GuoShouJing Road, Pudong New Area (Shanghai) pilot Free Trade Zone, Shanghai Applicant after: Zhenqu Technology (Shanghai) Co.,Ltd. Address before: 201203 3rd floor, building 19, building 8, No. 498, GuoShouJing Road, Pudong New Area (Shanghai) pilot Free Trade Zone, Shanghai Applicant before: ZHENQU TECHNOLOGY (SHANGHAI) CO.,LTD. Country or region before: China |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant |