CN116660715A - Aging detection system and method for driving transistor of electric power steering system - Google Patents
Aging detection system and method for driving transistor of electric power steering system Download PDFInfo
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- CN116660715A CN116660715A CN202310944397.9A CN202310944397A CN116660715A CN 116660715 A CN116660715 A CN 116660715A CN 202310944397 A CN202310944397 A CN 202310944397A CN 116660715 A CN116660715 A CN 116660715A
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- 238000001514 detection method Methods 0.000 title claims abstract description 114
- 230000032683 aging Effects 0.000 title claims abstract description 95
- 238000000034 method Methods 0.000 title claims description 8
- 238000012544 monitoring process Methods 0.000 claims abstract description 28
- 230000015556 catabolic process Effects 0.000 claims description 17
- 238000006731 degradation reaction Methods 0.000 claims description 17
- 238000005070 sampling Methods 0.000 claims description 15
- 238000007599 discharging Methods 0.000 claims description 6
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/26—Testing of individual semiconductor devices
- G01R31/2601—Apparatus or methods therefor
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/08—Measuring resistance by measuring both voltage and current
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/26—Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
- G01R27/2605—Measuring capacitance
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/26—Testing of individual semiconductor devices
- G01R31/2642—Testing semiconductor operation lifetime or reliability, e.g. by accelerated life tests
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Abstract
The invention relates to the technical field of aging detection, and provides an aging detection system and an aging detection method for a driving transistor of an electric power steering system. The aging detection system includes: a first current detection circuit detecting a first current value between a gate and a source of the driving transistor; a voltage detection circuit that detects a voltage value between a drain and a source of the driving transistor; a second current detection circuit detecting a second current value flowing through the drain and the source of the driving transistor; and the main controller is used for calculating a capacitance value according to the first current value, calculating a resistance value according to the voltage value and the second current value and monitoring the aging progress of the driving transistor according to the capacitance value and the resistance value. The invention monitors the aging progress of the driving transistor based on the detection of electric variables such as current between the grid electrode and the source electrode, voltage between the drain electrode and the source electrode, current flowing through the drain electrode and the source electrode and the like, so as to early warn in advance and improve the reliability and the safety of the electric power steering system.
Description
Technical Field
The invention relates to the technical field of aging detection, in particular to an aging detection system and an aging detection method for a driving transistor of an electric power steering system.
Background
The driving transistor is a key core component of a motor driving circuit of the electric power steering system, and aging of different degrees occurs after long-time operation, so that the performance of the driving transistor is reduced.
Currently, the driving transistor is subjected to aging detection by voltage data between the drain and the source of the driving transistor. According to the voltage data between the drain and the source, the aging degree of the driving transistor cannot be judged, and the aging degree can be detected only when the driving transistor has failed.
Specifically, when the driving transistor is not in failure, the voltage data between the drain electrode and the source electrode is a preset value, and only after the driving transistor is in failure, the voltage data between the drain electrode and the source electrode is abnormal, and at the moment, the electric power steering system can not normally provide power assistance, has potential safety hazards and is unfavorable for early maintenance before failure.
It should be noted that the information disclosed in the foregoing background section is only for enhancement of understanding of the background of the invention and thus may include information that does not form the prior art that is already known to those of ordinary skill in the art.
Disclosure of Invention
In view of the above, the present invention provides a system and a method for detecting aging of a driving transistor of an electric power steering system, which monitor the aging progress of the driving transistor based on detection of electric variables such as current between the gate and the source of the driving transistor, voltage between the drain and the source of the driving transistor, and current flowing through the drain and the source of the driving transistor by using a principle of capacitance change between the gate and the source and a principle of resistance change between the drain and the source during aging of the driving transistor, so as to make early warning in advance, thereby improving reliability and safety of the electric power steering system.
One aspect of the present invention provides an aging detection system for a driving transistor of an electric power steering system, including: a first current detection circuit connected to the gate and the source of the driving transistor and configured to detect a first current value between the gate and the source of the driving transistor; a voltage detection circuit connected to the drain and the source of the driving transistor and configured to detect a voltage value between the drain and the source of the driving transistor; a second current detection circuit connected to both ends of a feedback resistor connected in series with the driving transistor, configured to detect a second current value flowing through a drain and a source of the driving transistor; and the main controller is configured to calculate a capacitance value between the grid electrode and the source electrode of the driving transistor according to the first current value, calculate a resistance value between the drain electrode and the source electrode of the driving transistor according to the voltage value and the second current value, and monitor the aging progress of the driving transistor according to the capacitance value and the resistance value.
The aging detection system of the invention detects a first current value between a grid electrode and a source electrode of a driving transistor through a first current detection circuit so that a main controller calculates a capacitance value between the grid electrode and the source electrode of the driving transistor according to the first current value, and respectively detects a voltage value between a drain electrode and the source electrode of the driving transistor and a second current value flowing through the drain electrode and the source electrode of the driving transistor through a voltage detection circuit and a second current detection circuit so that the main controller calculates a resistance value between the drain electrode and the source electrode of the driving transistor according to the voltage value and the second current value; furthermore, based on the principle that parasitic capacitance between a gate and a source of the driving transistor is increased in the aging process of the driving transistor and on resistance between a drain and the source of the driving transistor is increased under the condition that the driving voltage of the gate is unchanged, the main controller can monitor the aging progress of the driving transistor according to the obtained capacitance value and resistance value so as to early warn in advance, and the reliability and the safety of the electric power steering system are improved.
In some embodiments, the main controller monitors the aging progress of the driving transistor according to the capacitance value and the resistance value, including: when the capacitance value is larger than a capacitance safety threshold and the resistance value is larger than a resistance safety threshold, monitoring future driving mileage based on smaller safety mileage of capacitance value safety mileage corresponding to the capacitance value and resistance value safety mileage corresponding to the resistance value; and when the future driving mileage exceeds the smaller safe mileage, sending out early warning information for prompting the aging of the driving transistor.
When the capacitance value and/or the resistance value is greater than the corresponding safety threshold value, the driving transistor starts to age; the capacitance value and the resistance value respectively have corresponding safety mileage, and if the vehicle continues to run beyond the corresponding safety mileage, the driving transistor is seriously aged and needs to be replaced; when the capacitance value is larger than the capacitance safety threshold and the resistance value is larger than the resistance safety threshold, the vehicle driving mileage is monitored based on the smaller safety mileage of the capacitance value safety mileage corresponding to the capacitance value and the smaller safety mileage of the resistance value safety mileage corresponding to the resistance value, the aging progress of the driving transistor can be accurately monitored, and early warning information is sent when the driving transistor is seriously aged.
In some embodiments, the master controller is further configured to: monitoring a first functional relation of capacitance between a grid electrode and a source electrode of the driving transistor along with historical driving mileage change; and the capacitance safety mileage is determined according to a limit capacitance value, the capacitance value and the first functional relation.
The first functional relation is obtained by monitoring the change of the capacitance between the grid electrode and the source electrode of the driving transistor along with the historical driving mileage, and the safety mileage of the volume value is accurately determined according to the first functional relation, the capacitance value and the limit capacitance value.
In some embodiments, the master controller is further configured to: monitoring a second functional relationship of resistance between the drain and the source of the drive transistor as a function of historical driving range; and the resistance safety mileage is determined according to a limiting resistance value, the resistance value and the second functional relation.
And obtaining a second functional relation by monitoring the change of the resistance between the drain electrode and the source electrode of the driving transistor along with the historical driving mileage, and accurately determining the resistance safety mileage according to the second functional relation, the resistance value and the limiting resistance value.
In some embodiments, the main controller monitors the aging progress of the driving transistor according to the capacitance value and the resistance value, including: when only the capacitance value is larger than a capacitance safety threshold, monitoring future driving mileage based on the capacitance value safety mileage corresponding to the capacitance value; and when the future driving mileage exceeds the capacity safety mileage, sending out early warning information for prompting the aging of the driving transistor.
Under the condition that the capacitance value is larger than the capacitance safety threshold value, the aging progress of the driving transistor can be accurately monitored based on the capacitance value safety mileage monitoring corresponding to the capacitance value, and early warning information is sent when the driving transistor is seriously aged.
In some embodiments, the main controller monitors the aging progress of the driving transistor according to the capacitance value and the resistance value, including: when the resistance value is larger than the resistance safety threshold, increasing the grid driving voltage of the driving transistor, and monitoring the future driving mileage based on the resistance safety mileage corresponding to the resistance value; and when the future driving distance exceeds the resistance safety distance, sending out early warning information for prompting the aging of the driving transistor.
Under the condition that the resistance value is larger than the resistance safety threshold, the on-resistance between the drain electrode and the source electrode of the driving transistor can be reduced by increasing the grid driving voltage, meanwhile, the vehicle driving mileage after the vehicle driving mileage is monitored based on the resistance value safety mileage corresponding to the resistance value, the aging progress of the driving transistor can be accurately monitored, and early warning information can be sent when the aging of the driving transistor is seriously monitored.
In some embodiments, the master controller is further configured to: when a vehicle starting signal is received next time, if the early warning information is not released, closing a power-assisted mode of the electric power-assisted steering system; and under the condition that the capacitance value is detected to be smaller than a capacitance safety threshold value and the resistance value is detected to be smaller than a resistance safety threshold value, the main controller releases the early warning information.
When the main controller monitors that the driving transistor is seriously aged, the main controller sends out early warning information to prompt a vehicle owner to replace the driving transistor in time; if the early warning information is processed, the main controller re-detects the capacitance value and the resistance value of the driving transistor, and releases the early warning information when detecting that the capacitance value and the resistance value are respectively smaller than the corresponding safety threshold values; when the next time the vehicle starts, if the main controller detects that the early warning information is not released, the aging problem of the driving transistor is not solved, and the electric power steering system is controlled not to provide power at the moment so as to avoid potential safety hazards caused by the abnormality of the electric power steering system and force a vehicle owner to replace the driving transistor as soon as possible.
In some embodiments, the master controller is further configured to: when the pre-driving mileage is greater than the remaining safety mileage, sending out early warning information for prompting the insufficient mileage of the driving transistor; the pre-driving mileage is obtained according to a navigation module of the vehicle or a navigation device communicated with the vehicle.
Under the condition that the pre-driving mileage is greater than the rest safety mileage, the continuous driving of the vehicle can bring potential safety hazards due to the fact that the driving transistor approaches the failure edge; at this time, the main controller sends out early warning information for prompting the insufficient mileage of the driving transistor so as to prompt the vehicle owner to replace the driving transistor in time and then run for a long distance.
In some embodiments, the electric power steering system includes a plurality of driving transistors, the first current detection circuit and the voltage detection circuit are respectively disposed corresponding to each driving transistor, and the feedback resistor is connected in series with each driving transistor; the main controller is configured to monitor the future driving mileage according to an aging progress of any driving transistor with a capacitance value greater than a capacitance safety threshold and/or a resistance value greater than a resistance safety threshold.
The motor driving circuit of the electric power steering system is generally provided with a plurality of driving transistors, and the main controller monitors that the capacitance value and/or the resistance value of any driving transistor is larger than the corresponding safety threshold value, namely, monitors the future driving range, so that the aging problem of the driving transistor can be accurately processed in time.
In some embodiments, the main controller calculates the capacitance value and the resistance value each time the main controller receives a vehicle start signal; alternatively, the main controller periodically calculates the capacitance value and the resistance value.
The calculation of the capacitance and resistance values may be performed each time the vehicle is started, or periodically at certain time intervals, in order to find out the aging problem of the driving transistor in time.
In some embodiments, the first current detection circuit comprises: the sampling resistor is connected in parallel between the grid electrode and the source electrode of the driving transistor; the two input ends of the first operational amplifier are respectively connected with the grid electrode and the source electrode of the driving transistor; a first resistor connected in series between the gate of the drive transistor and the inverting input terminal of the first operational amplifier; the second resistor is connected with the output end and the inverting input end of the first operational amplifier; the third resistor is connected in series between the source electrode of the driving transistor and the non-inverting input end of the first operational amplifier; and the fourth resistor is connected with the non-inverting input end of the first operational amplifier and grounded.
The sampling resistor is used for conveniently detecting a first current value between the grid electrode and the source electrode of the driving transistor; the first operational amplifier and the first to fourth resistors facilitate accurate calculation of a first current value between the gate and the source of the driving transistor based on a voltage value of an output terminal of the first operational amplifier by utilizing characteristics of the operational amplifier; and the second resistor is used as a negative feedback resistor of the first operational amplifier, and the fourth resistor is used as a pull-down resistor of the first operational amplifier, so that the first current detection circuit is stable and reliable.
In some embodiments, the main controller calculates the capacitance value from the first current value, comprising: calculating the potential difference between the grid electrode and the source electrode of the driving transistor according to the first current value and the resistance value of the sampling resistor; obtaining a third functional relation of the first current value along with the change of discharge time when the capacitance between the grid electrode and the source electrode of the driving transistor is discharged; calculating the charge quantity between the grid electrode and the source electrode of the driving transistor at the initial moment of discharging according to the third functional relation and the discharging time; the capacitance value is calculated from the charge amount and the potential difference.
The resistance value of the sampling resistor is an accurate value, and the potential difference between the grid electrode and the source electrode of the driving transistor is accurately calculated according to the first current value and the resistance value of the sampling resistor; according to a third functional relation that the first current value changes along with the discharge time when the capacitance between the grid electrode and the source electrode of the driving transistor is discharged and the discharge time, carrying out integral calculation to obtain the charge quantity between the grid electrode and the source electrode of the driving transistor at the initial moment of discharge; thus, the capacitance value is accurately calculated from the charge amount and the potential difference.
In some embodiments, the voltage detection circuit includes: the two input ends of the second operational amplifier are respectively connected with the drain electrode and the source electrode of the driving transistor; a fifth resistor connected in series between the drain of the drive transistor and the inverting input terminal of the second operational amplifier; a sixth resistor connected to the output terminal and the inverting input terminal of the second operational amplifier; a seventh resistor connected in series between the source of the driving transistor and the non-inverting input terminal of the second operational amplifier; and the eighth resistor is connected with the non-inverting input end of the second operational amplifier and grounded.
Through the second operational amplifier and the fifth to eighth resistors, it is convenient to accurately calculate the potential difference between the drain and the source of the driving transistor, i.e., the voltage value, based on the voltage value of the output terminal of the second operational amplifier by utilizing the characteristics of the operational amplifier; and the sixth resistor is used as a negative feedback resistor of the second operational amplifier, and the eighth resistor is used as a pull-down resistor of the second operational amplifier, so that the voltage detection circuit is stable and reliable.
In some embodiments, the second current detection circuit includes: the two input ends of the third operational amplifier are respectively connected with the two ends of the feedback resistor; a ninth resistor connected in series between the series end of the feedback resistor and the inverting input end of the third operational amplifier; a tenth resistor connected to the output terminal and the inverting input terminal of the third operational amplifier; an eleventh resistor connected in series between the ground terminal of the feedback resistor and the non-inverting input terminal of the third operational amplifier; and a twelfth resistor connected with the non-inverting input end of the third operational amplifier and grounded.
The second current value flowing through the drain electrode and the source electrode of the driving transistor is conveniently detected through the feedback resistor; through the third operational amplifier and the ninth to twelfth resistors, it is convenient to accurately calculate the second current value flowing through the drain and the source of the driving transistor based on the voltage value of the output terminal of the third operational amplifier by utilizing the characteristics of the operational amplifier; and the tenth resistor is used as a negative feedback resistor of the third operational amplifier, and the twelfth resistor is used as a pull-down resistor of the third operational amplifier, so that the second current detection circuit is stable and reliable.
A further aspect of the present invention provides an aging detection method for a driving transistor of an electric power steering system, based on the aging detection system according to any of the above embodiments, the aging detection method including: detecting a first current value between a gate and a source of the driving transistor by the first current detection circuit; detecting a voltage value between a drain and a source of the driving transistor by the voltage detection circuit; detecting a second current value flowing through the drain and the source of the driving transistor by the second current detection circuit; and calculating a capacitance value between the grid electrode and the source electrode of the driving transistor according to the first current value by the main controller, calculating a resistance value between the drain electrode and the source electrode of the driving transistor according to the voltage value and the second current value, and monitoring the aging progress of the driving transistor according to the capacitance value and the resistance value.
According to the aging detection method, a first current value between the grid electrode and the source electrode of the driving transistor is detected through a first current detection circuit, so that the main controller calculates a capacitance value between the grid electrode and the source electrode of the driving transistor according to the first current value, and a voltage value between the drain electrode and the source electrode of the driving transistor and a second current value flowing through the drain electrode and the source electrode of the driving transistor are respectively detected through a voltage detection circuit and a second current detection circuit, so that the main controller calculates a resistance value between the drain electrode and the source electrode of the driving transistor according to the voltage value and the second current value; furthermore, based on the principle that parasitic capacitance between a gate and a source of the driving transistor is increased in the aging process of the driving transistor and on resistance between a drain and the source of the driving transistor is increased under the condition that the driving voltage of the gate is unchanged, the main controller can monitor the aging progress of the driving transistor according to the obtained capacitance value and resistance value so as to early warn in advance, and the reliability and the safety of the electric power steering system are improved.
Compared with the prior art, the invention has the beneficial effects that at least:
the invention utilizes the principle of the change of the parasitic capacitance between the grid electrode and the source electrode of the driving transistor in the aging process and the resistance between the drain electrode and the source electrode of the driving transistor under the condition of unchanged grid electrode driving voltage, and monitors the aging progress of the driving transistor based on the detection of the current between the grid electrode and the source electrode of the driving transistor, the voltage between the drain electrode and the source electrode of the driving transistor, the current flowing through the drain electrode and the source electrode of the driving transistor and other electrical variables, so as to early warn in advance and improve the reliability and the safety of an electric power steering system.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and together with the description, serve to explain the principles of the invention. It is evident that the figures described below are only some embodiments of the invention, from which other figures can be obtained without inventive effort for a person skilled in the art.
Fig. 1 is a schematic diagram showing a structure of a motor drive circuit of an electric power steering system in an embodiment of the invention;
FIG. 2 is a block diagram of a system for detecting degradation of a driving transistor of an electric power steering system according to an embodiment of the present invention;
FIG. 3 is a schematic diagram showing a first current detection circuit according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of a third functional relationship in an embodiment of the present invention;
FIG. 5 is a schematic diagram showing a voltage detection circuit according to an embodiment of the present invention;
FIG. 6 is a schematic diagram showing a structure of a second current detection circuit according to an embodiment of the present invention;
FIG. 7 is a schematic diagram showing a process flow of the main controller on the aging progress of the abnormal capacitance/resistance of the driving transistor according to the embodiment of the present invention;
fig. 8 is a schematic diagram showing steps of a method for detecting aging of a driving transistor of an electric power steering system according to an embodiment of the present invention.
Detailed Description
Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art.
The drawings are merely schematic illustrations of the present invention and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and thus a repetitive description thereof will be omitted. Some of the block diagrams shown in the figures are functional entities and do not necessarily correspond to physically or logically separate entities. These functional entities may be implemented in software or in one or more hardware modules or integrated circuits or in different networks and/or processor devices and/or microcontroller devices.
Furthermore, the flow shown in the drawings is merely illustrative and not necessarily all steps are included. For example, some steps may be decomposed, some steps may be combined or partially combined, and the order of actual execution may be changed according to actual situations. The use of the terms "first," "second," and the like in the description herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another.
It should be noted that, without conflict, the embodiments of the present invention and features in different embodiments may be combined with each other.
Fig. 1 shows a structure of a motor drive circuit of an electric power steering system (Electric Power Steering, EPS); referring to fig. 1, an electric power steering system generally employs a dc brushless motor, which is driven by a three-PHASE six-leg driving circuit, and controls the switching states of six driving transistors (including first to sixth driving transistors Q1 to Q6) through a main controller to drive three-PHASE windings phase_ U, PHASE _v and phase_w to operate. Wherein, V_PHASE is the supply voltage, and main control unit can be ECU (Electronic Control Unit ), and drive transistor can adopt the field effect transistor, but does not limit to this.
When the circuit works, the main controller applies a certain frequency electric signal to the grid electrode of the driving transistor, so that the drain electrode and the source electrode of the driving transistor are switched between closed and saturated on; the driving transistor can be aged in an undesireable way under the conditions of frequent switching state electric stress and EPS inherent temperature and humidity. It was found that the parasitic capacitance between the gate and the source increases as the drive transistor ages, while the on-resistance between the drain and the source increases under a fixed gate drive voltage.
The invention utilizes the principle of capacitance change between the grid electrode and the source electrode and the principle of resistance change between the drain electrode and the source electrode in the aging process of the driving transistor, and based on the detection of the current between the grid electrode and the source electrode of the driving transistor, the voltage between the drain electrode and the source electrode of the driving transistor, the current flowing through the drain electrode and the source electrode of the driving transistor and other electric variables, the capacitance value between the grid electrode and the source electrode of the driving transistor and the resistance value between the drain electrode and the source electrode of the driving transistor are obtained in real time, so that the aging progress of the driving transistor is monitored, early warning is made in advance, and the reliability and the safety of the electric power steering system are improved.
FIG. 2 shows the main modules of an aging detection system for the drive transistor of an electric power steering system; referring to fig. 2, an aging detection system for a driving transistor of an electric power steering system according to an embodiment of the present invention includes:
A first current detection circuit 210 connected to the gate G and the source S of the driving transistor Q and configured to detect a first current value between the gate G and the source S of the driving transistor Q;
a voltage detection circuit 220 connected to the drain D and the source S of the driving transistor Q and configured to detect a voltage value between the drain D and the source S of the driving transistor Q;
a second current detection circuit 230 connected to a series terminal RF1 and a ground terminal RF2 of a feedback resistor RF connected in series with the driving transistor Q, configured to detect a second current value flowing through the drain D and the source S of the driving transistor Q;
the main controller 240 is configured to calculate a capacitance value between the gate G and the source S of the driving transistor Q according to the first current value, calculate a resistance value between the drain D and the source S of the driving transistor Q according to the voltage value and the second current value, and monitor an aging progress of the driving transistor Q according to the capacitance value and the resistance value.
In the above aging detection system, the first current detection circuit 210 detects the first current value between the gate G and the source S of the driving transistor Q, so that the main controller 240 calculates the capacitance value between the gate G and the source S of the driving transistor Q according to the first current value, and the voltage detection circuit 220 and the second current detection circuit 230 respectively detect the voltage value between the drain D and the source S of the driving transistor Q and the second current value flowing through the drain D and the source S of the driving transistor Q, so that the main controller 240 calculates the resistance value between the drain D and the source S of the driving transistor Q according to the voltage value and the second current value; further, based on the principle of variation in which parasitic capacitance between the gate G and the source S increases during the aging of the driving transistor Q and on-resistance between the drain D and the source S increases with the gate driving voltage unchanged, the main controller 240 can monitor the aging progress of the driving transistor Q according to the obtained capacitance value and resistance value, so as to make early warning in advance, and improve the reliability and safety of the electric power steering system.
In some embodiments, as shown in connection with fig. 1 and 2, the electric power steering system includes first to sixth driving transistors Q1 to Q6, and the driving transistor Q shown in fig. 2 may be any one of the first to sixth driving transistors Q1 to Q6. The first current detection circuit 210 and the voltage detection circuit 220 are respectively provided corresponding to each driving transistor, and a feedback resistor RF is connected in series with each driving transistor so as to detect a current flowing through each driving transistor.
Fig. 3 shows a structure of a first current detection circuit; as shown in fig. 1 to 3, taking the first driving transistor Q1 as an example, in some embodiments, the first current detection circuit 210 includes:
the sampling resistor RS is connected in parallel between the grid electrode G1 and the source electrode S1 of the first driving transistor Q1;
the first operational amplifier A1, two input ends of the first operational amplifier A1 are connected with the grid G1 and the source S1 of the first driving transistor Q1 respectively;
the first resistor R1 is connected in series between the grid G1 of the first driving transistor Q1 and the inverting input end of the first operational amplifier A1;
the second resistor R2 is connected with the output end OUT1 and the inverting input end of the first operational amplifier A1;
the third resistor R3 is connected in series between the source electrode S1 of the first driving transistor Q1 and the non-inverting input end of the first operational amplifier A1;
And a fourth resistor R4 connected with the non-inverting input end of the first operational amplifier A1 and grounded.
Through the sampling resistor RS, it is convenient to detect a first current value between the gate G1 and the source S1 of the first driving transistor Q1; by the first operational amplifier A1 and the first to fourth resistors, it is convenient to accurately calculate the first current value between the gate G1 and the source S1 of the first driving transistor Q1 based on the voltage value of the output terminal OUT1 of the first operational amplifier A1 by utilizing the characteristics of the operational amplifier; and the second resistor R2 serves as a negative feedback resistor of the first operational amplifier A1, and the fourth resistor R4 serves as a pull-down resistor of the first operational amplifier A1, so that the first current detection circuit 210 is stable and reliable.
Specifically, let the voltage value of the output terminal OUT1 be Uout1, the current value flowing through the sampling resistor RS, that Is, the first current value Is, the voltage of the gate G1 be ug1, the voltage of the source S1 be Us1, and the potential difference across the two ends be ugs=is×rss 1. The following equation is obtained according to the principle of the virtual break and the virtual short of the operational amplifier:
(Uout1－Ug1)÷(R1＋R2)×R1＋Ug1＝Us1×R4÷(R3＋R4)；
where r1=r2=r3=r4, the solution equation can be: ug1-Us1=Uout1=Ugs=is×RS1, so the following Is obtained: is=uout1+.rs 1, where Uout1 Is directly measurable by the main controller 240, RS1 Is a known, accurate resistance of the sampling resistor RS.
Further, in some embodiments, the main controller calculates a capacitance value from the first current value, comprising: calculating the potential difference between the grid electrode and the source electrode of the first driving transistor according to the first current value and the resistance value of the sampling resistor; obtaining a third functional relation of the first current value changing along with the discharge time when the capacitance between the grid electrode and the source electrode of the first driving transistor is discharged; calculating the charge quantity between the grid electrode and the source electrode of the first driving transistor at the initial moment of discharging according to the third functional relation and the discharging time; the capacitance value is calculated from the charge amount and the potential difference.
Specifically, as shown in fig. 1 to 3, taking the first driving transistor Q1 as an example, the resistance value RS1 of the sampling resistor RS Is an accurate value, and the potential difference ugs=is×r1 between the gate G1 and the source S1 of the first driving transistor Q1 Is accurately calculated from the first current value Is between the gate G1 and the source S1 of the first driving transistor Q1 and the resistance value RS1 of the sampling resistor RS.
FIG. 4 shows a graphical illustration of a third functional relationship; as shown in fig. 1 to 4, when the gate G1 of the first driving transistor Q1 Is switched from the on state to the off state, the parasitic capacitance Cgs between the gate G1 and the source S1 thereof Is in the discharge state, and the current change flowing through the sampling resistor RS during the discharge of the parasitic capacitance Cgs, that Is, the change of the first current value Is with the discharge time T Is detected, a third functional relation f (T) as shown in fig. 4 Is obtained. According to the third functional relation f (t) and the discharge time from t1 to t2, the charge quantity Qgs of the parasitic capacitance Cgs at two ends of the discharge moment is calculated through integral operation:
。
Further, the capacitance value c=qgs/Ugs is accurately calculated from the charge amount Qgs and the potential difference Ugs. In this way, based on the first current value Is between the gate G1 and the source S1 of the first driving transistor Q1, the main controller 240 may calculate the capacitance value C of the parasitic capacitance Cgs between the gate G1 and the source S1 in real time, where the capacitance value C of the parasitic capacitance Cgs directly reflects the insulation aging state between the gate G1 and the source S1.
The current detection circuit and the capacitance calculation principle between the gate and the source of the second driving transistor Q2 to the sixth driving transistor Q6 are the same, and the description thereof will not be repeated.
Fig. 5 shows a structure of the voltage detection circuit; as shown in fig. 1, 2 and 5, taking the first driving transistor Q1 as an example, in some embodiments, the voltage detection circuit 220 includes:
the two input ends of the second operational amplifier A2 are respectively connected with the drain electrode D1 and the source electrode S1 of the first driving transistor Q1;
a fifth resistor R5 connected in series between the drain D1 of the first driving transistor Q1 and the inverting input terminal of the second operational amplifier A2;
a sixth resistor R6 connected to the output terminal OUT2 and the inverting input terminal of the second operational amplifier A2;
a seventh resistor R7 connected in series between the source S1 of the first driving transistor Q1 and the non-inverting input terminal of the second operational amplifier A2;
And an eighth resistor R8 connected with the non-inverting input end of the second operational amplifier A2 and grounded.
By the second operational amplifier A2 and the fifth to eighth resistors, it is convenient to accurately calculate the potential difference between the drain D1 and the source S1 of the first driving transistor Q1, i.e., the voltage value, based on the voltage value of the output terminal OUT2 of the second operational amplifier A2 by utilizing the characteristics of the operational amplifiers; and the sixth resistor R6 serves as a negative feedback resistor of the second operational amplifier A2, and the eighth resistor R8 serves as a pull-down resistor of the second operational amplifier A2, so that the voltage detection circuit 220 is stable and reliable.
Specifically, the output terminal OUT2 of the second operational amplifier A2 is connected to the main controller 240, and the voltage value of the output terminal OUT2 is Uout2, the voltage of the drain D1 is Ud1, the voltage of the source S1 is Us1, and the potential difference between the two ends is Uds. The following equation is obtained according to the principle of the virtual short and the virtual break of the operational amplifier:
(Uout2－Ud1)÷(R5＋R6)×R5＋Ud1＝Us1×R8÷(R7＋R8)；
where r5=r6=r7=r8, the solution equation can be: us 1-ud1=uout2=uds.
Fig. 6 shows a structure of a second current detection circuit; as shown in fig. 1, 2, 5, and 6, taking the first driving transistor Q1 as an example, in some embodiments, the second current detection circuit 230 includes:
the two input ends of the third operational amplifier A3 are respectively connected with a serial end RF1 and a grounding end RF2 of a feedback resistor RF;
A ninth resistor R9 connected in series between the series terminal RF1 of the feedback resistor RF and the inverting input terminal of the third operational amplifier A3;
a tenth resistor R10 connected to the output terminal OUT3 and the inverting input terminal of the third operational amplifier A3;
an eleventh resistor R11 connected in series between the ground terminal RF2 of the feedback resistor RF and the non-inverting input terminal of the third operational amplifier A3;
the twelfth resistor R12 is connected to the non-inverting input terminal of the third operational amplifier A3 and to the ground.
The second current value flowing through the drain D1 and the source S1 of the first driving transistor Q1 is facilitated to be detected by the feedback resistor RF; by the third operational amplifier A3 and the ninth to twelfth resistors, it is convenient to accurately calculate the second current value flowing through the drain D1 and the source S1 of the first driving transistor Q1 based on the voltage value of the output terminal OUT3 of the third operational amplifier A3 by using the characteristics of the third operational amplifier A3; and the tenth resistor R10 serves as a negative feedback resistor of the third operational amplifier A3, and the twelfth resistor R12 serves as a pull-down resistor of the third operational amplifier A3, so that the second current detection circuit 230 is stable and reliable.
Specifically, the output terminal OUT3 of the third operational amplifier A3 is connected to the main controller 240, where the resistance of the feedback resistor RF is RF1, the current value flowing through the feedback resistor RF, that is, the second current value flowing through the drain D1 and the source S1 of the first driving transistor Q1 is If, the voltages across the feedback resistor RF are Uf1 and Uf2, respectively, and the potential difference across the feedback resistor RF is uf=if×rf1. The following equation is obtained according to the principle of the virtual short and the virtual break of the operational amplifier:
(Uout3－Uf1)÷(R9＋R10)×R9＋Uf1＝Uf2×R12÷(R11＋R12)；
Where r9=r10=r11=r12, the solution equation can be: uf1-uf2=uot3=uf=if×rf1, so the result is: if=uot3++rf 1.
In this way, it can be deduced that the resistance value Rds of the on-resistance between the drain D1 and the source S1 of the first driving transistor Q1 when the gate driving voltage is turned on is: rds=uds ≡if.
The voltage detection circuit and the current detection circuit between the drain and the source of the second driving transistor Q2 to the sixth driving transistor Q6 are the same as the resistance value calculation principle, and the description thereof will not be repeated.
In some embodiments, the main controller calculates a capacitance value between the gate and the source and a resistance value between the drain and the source of each driving transistor each time the main controller receives the vehicle start signal; alternatively, the main controller periodically calculates a capacitance value between the gate and the source and a resistance value between the drain and the source of each driving transistor.
In this way, the calculation of the capacitance and resistance values can be performed each time the vehicle is started, or periodically at certain time intervals, so as to find the aging problem of the driving transistor in time. The periodic time interval may be in units of hours (preferably in a range of 1h to 100 h) or in units of days; in each detection, detection is performed for a plurality of times at millisecond intervals so as to ensure the reliability of detection results.
In some embodiments, the main controller monitors the aging progress of the driving transistor according to the capacitance value and the resistance value, including: when the capacitance value is larger than the capacitance safety threshold and the resistance value is larger than the resistance safety threshold, monitoring future driving mileage based on smaller safety mileage of capacitance value safety mileage corresponding to the capacitance value and resistance value safety mileage corresponding to the resistance value; and when the future driving mileage exceeds the smaller safe mileage, sending out early warning information for prompting the aging of the driving transistor.
When the capacitance value and/or the resistance value is greater than the corresponding safety threshold value, the driving transistor starts to age; the capacitance value and the resistance value respectively have corresponding safety mileage, and if the vehicle continues to run beyond the corresponding safety mileage, the driving transistor is seriously aged and needs to be replaced; when the capacitance value is larger than the capacitance safety threshold and the resistance value is larger than the resistance safety threshold, the vehicle driving mileage is monitored based on the smaller safety mileage of the capacitance value safety mileage corresponding to the capacitance value and the smaller safety mileage of the resistance value safety mileage corresponding to the resistance value, so that the aging progress of the driving transistor is accurately monitored, and early warning information is sent when the driving transistor is seriously aged.
Further, in some embodiments, the master controller is further configured to: monitoring a first functional relationship of capacitance between a gate and a source of the driving transistor along with historical driving mileage changes; the capacitance safety mileage is determined according to the limit capacitance value, the capacitance value and the first functional relation.
Depending on the characteristics of the materials of the driving transistor, the first functional relationship, such as a linear growth relationship, a logarithmic growth relationship, an exponential growth relationship, etc., in which the parasitic capacitance between the gate and the source increases with the increase of the historical driving mileage, can be accurately obtained by monitoring the change of the capacitance between the gate and the source of the driving transistor with the increase of the historical driving mileage. The limit capacitance is the capacitance of the driving transistor in the near failure, and can be obtained through testing. According to the first functional relation, the current capacitance value and the limit capacitance value, the safety mileage of the capacitance value which can be driven can be accurately determined.
In some embodiments, the master controller is further configured to: monitoring a second functional relationship of resistance between the drain and the source of the drive transistor as a function of historical driving range; and the resistance safety mileage is determined according to the limit resistance value, the resistance value and the second functional relation.
Similarly, depending on the characteristics of the materials of the driving transistor, the second functional relationship that the on-resistance between the drain and the source increases with the increase of the historical driving mileage may be a linear relationship, a logarithmic relationship, an exponential relationship, or the like, and may be accurately obtained by monitoring the change of the resistance between the drain and the source of the driving transistor with the change of the historical driving mileage. The limiting resistance is the resistance of the driving transistor in the event of failure, and can be obtained through testing. According to the second functional relation, the current resistance value and the limiting resistance value, the resistance value safety mileage which can be driven can be accurately determined.
In some embodiments, the main controller monitors the aging progress of the driving transistor according to the capacitance value and the resistance value, including: when the capacitance value is larger than the capacitance safety threshold, monitoring the future driving mileage based on the capacitance value safety mileage corresponding to the capacitance value; and when the future driving distance exceeds the capacity safety distance, sending out early warning information for prompting the aging of the driving transistor.
Under the condition that the capacitance value is larger than the capacitance safety threshold value, the vehicle driving mileage is monitored based on the capacitance value safety mileage corresponding to the capacitance value, the aging progress of the driving transistor can be accurately monitored, and early warning information is sent when the driving transistor is seriously aged.
In some embodiments, the main controller monitors the aging progress of the driving transistor according to the capacitance value and the resistance value, including: when the resistance value is larger than the resistance safety threshold, increasing the grid driving voltage of the driving transistor, and monitoring the future driving mileage based on the resistance safety mileage corresponding to the resistance value; and when the future driving distance exceeds the resistance value safety distance, sending out early warning information for prompting the aging of the driving transistor.
Under the condition that the resistance value is larger than the resistance safety threshold, increasing the grid driving voltage can reduce the on resistance between the drain electrode and the source electrode of the driving transistor, and meanwhile, the main controller monitors the vehicle driving mileage based on the resistance value safety mileage corresponding to the resistance value, so that the aging progress of the driving transistor is accurately monitored, and early warning information is sent when the driving transistor is seriously aged.
Fig. 7 shows a process flow of the main controller for the aging progress of the abnormal capacitance/resistance value of the driving transistor; as shown in fig. 1 and 7, the process flow of the main controller on the aging progress of the abnormal capacitance value and/or resistance value of the driving transistor includes:
s710, the main controller calculates a capacitance value between the gate and the source and a resistance value between the drain and the source of the driving transistor at a prescribed time interval. Wherein the prescribed time interval is self-checked, for example, each time the vehicle is started, or periodically. The calculation of the capacitance and resistance values can be described with reference to the above embodiments.
S720, judging whether the capacitance value is larger than a capacitance safety threshold value or not and whether the resistance value is larger than a resistance safety threshold value or not; if yes, entering the subsequent step, otherwise returning to S710 to continue monitoring.
And S730a, when the capacitance value is larger than the capacitance safety threshold and the resistance value is larger than the resistance safety threshold, taking the smaller safety mileage of the capacitance value safety mileage corresponding to the capacitance value and the resistance value safety mileage corresponding to the resistance value as the final safety mileage, and monitoring the future driving mileage.
And S730b, when the capacitance value is larger than the capacitance safety threshold, taking the capacitance safety mileage as the final safety mileage, and monitoring the future driving mileage.
And S730c, when the resistance value is larger than the resistance safety threshold, increasing the grid driving voltage of the driving transistor, taking the resistance safety mileage as the final safety mileage, and monitoring the future driving mileage.
And S740, when the future driving distance exceeds the final safety distance, sending out early warning information for prompting the aging of the driving transistor. Thus, the driving transistor of the EPS of the vehicle owner is prompted to be seriously aged and needs to be checked and replaced in time so as to avoid potential safety hazards.
In some embodiments, as shown in connection with FIG. 1, an electric power steering system includes a plurality of drive transistors; the main controller is configured to monitor future driving mileage according to the aging progress of any driving transistor with a capacitance value greater than a capacitance safety threshold and/or a resistance value greater than a resistance safety threshold so as to timely and accurately treat the aging problem of the driving transistor.
In some embodiments, the master controller is further configured to: when a vehicle starting signal is received next time, if the early warning information is not released, closing a power assisting mode of the electric power steering system; and under the condition that the capacitance value is smaller than the capacitance safety threshold value and the resistance value is smaller than the resistance safety threshold value, the main controller releases the early warning information.
When the main controller monitors that the driving transistor is seriously aged, the main controller sends out early warning information to prompt a vehicle owner to replace the driving transistor in time; if the early warning information is processed, the main controller can re-detect the capacitance value and the resistance value of the driving transistor, and release the early warning information when detecting that the capacitance value and the resistance value are respectively smaller than the corresponding safety threshold values. When the next time the vehicle starts, if the main controller detects that the early warning information is not released, the aging problem of the driving transistor is not solved, and the electric power steering system is controlled not to provide power at the moment so as to avoid potential safety hazards caused by the abnormality of the electric power steering system and force a vehicle owner to replace the driving transistor as soon as possible.
In some embodiments, the master controller is further configured to: when the pre-driving mileage is greater than the remaining safety mileage, sending out early warning information for prompting insufficient mileage of the driving transistor; the pre-driving mileage is obtained according to a navigation module of the vehicle or a navigation device communicated with the vehicle.
Under the condition that the pre-driving mileage is greater than the rest safety mileage, the continuous driving of the vehicle can bring potential safety hazards due to the fact that the driving transistor approaches the failure edge; at this time, the main controller sends out early warning information for prompting the insufficient mileage of the driving transistor so as to prompt the vehicle owner to replace the driving transistor in time and then run for a long distance.
For example, the main controller monitors the remaining safe mileage (which can be determined by deducting the already-driven mileage from the safe mileage determined when the monitored capacitance/resistance value is abnormal) as 200km, and when the navigation module of the vehicle or the smart phone communicating with the vehicle acquires the navigation information of the vehicle that is going to run for 1000km, the main controller determines that the pre-driven mileage is greater than the remaining safe mileage, and sends out the early warning information for prompting the insufficient driving transistor mileage.
The embodiment of the invention also provides an aging detection method of the driving transistor of the electric power steering system, which can be realized based on the aging detection system described in any embodiment. Fig. 8 shows main steps of an aging detection method for a driving transistor of an electric power steering system, and referring to fig. 8, the aging detection method provided by an embodiment of the present invention includes:
s810 detecting a first current value between the gate and the source of the driving transistor by a first current detection circuit;
s820, detecting a voltage value between a drain electrode and a source electrode of the driving transistor through a voltage detection circuit;
s830, detecting a second current value flowing through the drain electrode and the source electrode of the driving transistor through a second current detection circuit;
And S840, calculating a capacitance value between the grid electrode and the source electrode of the driving transistor according to the first current value by the main controller, calculating a resistance value between the drain electrode and the source electrode of the driving transistor according to the voltage value and the second current value, and monitoring the aging progress of the driving transistor according to the capacitance value and the resistance value.
In the aging detection method, a first current value between the gate and the source of the driving transistor is detected by the first current detection circuit, so that the main controller calculates a capacitance value between the gate and the source of the driving transistor according to the first current value, and a voltage value between the drain and the source of the driving transistor and a second current value flowing through the drain and the source of the driving transistor are respectively detected by the voltage detection circuit and the second current detection circuit, so that the main controller calculates a resistance value between the drain and the source of the driving transistor according to the voltage value and the second current value; furthermore, based on the principle that parasitic capacitance between a gate and a source of the driving transistor is increased in the aging process of the driving transistor and on resistance between a drain and the source of the driving transistor is increased under the condition that the driving voltage of the gate is unchanged, the main controller can monitor the aging progress of the driving transistor according to the obtained capacitance value and resistance value so as to early warn in advance, and the reliability and the safety of the electric power steering system are improved.
In summary, the aging detection system and the aging detection method of the present invention use the principle that parasitic capacitance between the gate and the source of the driving transistor increases during aging, and resistance between the drain and the source of the driving transistor increases under the condition that the driving voltage of the gate is unchanged, and based on detection of electric variables such as current between the gate and the source of the driving transistor, voltage between the drain and the source of the driving transistor, and current flowing through the drain and the source of the driving transistor, the aging progress of the driving transistor is monitored, so as to make early warning in advance, and improve the reliability and safety of the electric power steering system.
The foregoing is a further detailed description of the invention in connection with the preferred embodiments, and it is not intended that the invention be limited to the specific embodiments described. It will be apparent to those skilled in the art that several simple deductions or substitutions may be made without departing from the spirit of the invention, and these should be considered to be within the scope of the invention.
Claims (15)
1. An aging detection system for a drive transistor of an electric power steering system, comprising:
a first current detection circuit connected to the gate and the source of the driving transistor and configured to detect a first current value between the gate and the source of the driving transistor;
A voltage detection circuit connected to the drain and the source of the driving transistor and configured to detect a voltage value between the drain and the source of the driving transistor;
a second current detection circuit connected to both ends of a feedback resistor connected in series with the driving transistor, configured to detect a second current value flowing through a drain and a source of the driving transistor;
and the main controller is configured to calculate a capacitance value between the grid electrode and the source electrode of the driving transistor according to the first current value, calculate a resistance value between the drain electrode and the source electrode of the driving transistor according to the voltage value and the second current value, and monitor the aging progress of the driving transistor according to the capacitance value and the resistance value.
2. The degradation detection system of claim 1, wherein the main controller monitors the degradation progress of the driving transistor based on the capacitance value and the resistance value, comprising:
when the capacitance value is larger than a capacitance safety threshold and the resistance value is larger than a resistance safety threshold, monitoring future driving mileage based on smaller safety mileage of capacitance value safety mileage corresponding to the capacitance value and resistance value safety mileage corresponding to the resistance value;
And when the future driving mileage exceeds the smaller safe mileage, sending out early warning information for prompting the aging of the driving transistor.
3. The degradation detection system of claim 2, wherein the master controller is further configured to:
monitoring a first functional relation of capacitance between a grid electrode and a source electrode of the driving transistor along with historical driving mileage change;
and the capacitance safety mileage is determined according to a limit capacitance value, the capacitance value and the first functional relation.
4. The degradation detection system of claim 2, wherein the master controller is further configured to:
monitoring a second functional relationship of resistance between the drain and the source of the drive transistor as a function of historical driving range;
and the resistance safety mileage is determined according to a limiting resistance value, the resistance value and the second functional relation.
5. The degradation detection system of claim 1, wherein the main controller monitors the degradation progress of the driving transistor based on the capacitance value and the resistance value, comprising:
when only the capacitance value is larger than a capacitance safety threshold, monitoring future driving mileage based on the capacitance value safety mileage corresponding to the capacitance value;
And when the future driving mileage exceeds the capacity safety mileage, sending out early warning information for prompting the aging of the driving transistor.
6. The degradation detection system of claim 1, wherein the main controller monitors the degradation progress of the driving transistor based on the capacitance value and the resistance value, comprising:
when the resistance value is larger than the resistance safety threshold, increasing the grid driving voltage of the driving transistor, and monitoring the future driving mileage based on the resistance safety mileage corresponding to the resistance value;
and when the future driving distance exceeds the resistance safety distance, sending out early warning information for prompting the aging of the driving transistor.
7. The degradation detection system of any one of claims 2, 5, and 6, wherein the master controller is further configured to:
when a vehicle starting signal is received next time, if the early warning information is not released, closing a power-assisted mode of the electric power-assisted steering system;
and under the condition that the capacitance value is detected to be smaller than a capacitance safety threshold value and the resistance value is detected to be smaller than a resistance safety threshold value, the main controller releases the early warning information.
8. The degradation detection system of any one of claims 2, 5, and 6, wherein the master controller is further configured to:
When the pre-driving mileage is greater than the remaining safety mileage, sending out early warning information for prompting the insufficient mileage of the driving transistor;
the pre-driving mileage is obtained according to a navigation module of the vehicle or a navigation device communicated with the vehicle.
9. The degradation detection system according to any one of claims 2, 5, and 6, wherein the electric power steering system includes a plurality of driving transistors, the first current detection circuit and the voltage detection circuit are respectively provided corresponding to each driving transistor, and the feedback resistor is connected in series with each driving transistor;
the main controller is configured to monitor the future driving mileage according to an aging progress of any driving transistor with a capacitance value greater than a capacitance safety threshold and/or a resistance value greater than a resistance safety threshold.
10. The degradation detection system according to claim 1, wherein the main controller calculates the capacitance value and the resistance value each time it receives a vehicle start signal;
alternatively, the main controller periodically calculates the capacitance value and the resistance value.
11. The degradation detection system of claim 1, wherein the first current detection circuit comprises:
The sampling resistor is connected in parallel between the grid electrode and the source electrode of the driving transistor;
the two input ends of the first operational amplifier are respectively connected with the grid electrode and the source electrode of the driving transistor;
a first resistor connected in series between the gate of the drive transistor and the inverting input terminal of the first operational amplifier;
the second resistor is connected with the output end and the inverting input end of the first operational amplifier;
the third resistor is connected in series between the source electrode of the driving transistor and the non-inverting input end of the first operational amplifier;
and the fourth resistor is connected with the non-inverting input end of the first operational amplifier and grounded.
12. The degradation detection system of claim 11, wherein the main controller calculating the capacitance value from the first current value comprises:
calculating the potential difference between the grid electrode and the source electrode of the driving transistor according to the first current value and the resistance value of the sampling resistor;
obtaining a third functional relation of the first current value along with the change of discharge time when the capacitance between the grid electrode and the source electrode of the driving transistor is discharged;
calculating the charge quantity between the grid electrode and the source electrode of the driving transistor at the initial moment of discharging according to the third functional relation and the discharging time;
The capacitance value is calculated from the charge amount and the potential difference.
13. The degradation detection system of claim 1, wherein the voltage detection circuit comprises:
the two input ends of the second operational amplifier are respectively connected with the drain electrode and the source electrode of the driving transistor;
a fifth resistor connected in series between the drain of the drive transistor and the inverting input terminal of the second operational amplifier;
a sixth resistor connected to the output terminal and the inverting input terminal of the second operational amplifier;
a seventh resistor connected in series between the source of the driving transistor and the non-inverting input terminal of the second operational amplifier;
and the eighth resistor is connected with the non-inverting input end of the second operational amplifier and grounded.
14. The degradation detection system of claim 1, wherein the second current detection circuit comprises:
the two input ends of the third operational amplifier are respectively connected with the two ends of the feedback resistor;
a ninth resistor connected in series between the series end of the feedback resistor and the inverting input end of the third operational amplifier;
a tenth resistor connected to the output terminal and the inverting input terminal of the third operational amplifier;
An eleventh resistor connected in series between the ground terminal of the feedback resistor and the non-inverting input terminal of the third operational amplifier;
and a twelfth resistor connected with the non-inverting input end of the third operational amplifier and grounded.
15. A method of aging detection for a drive transistor of an electric power steering system, characterized in that the aging detection method comprises, based on the aging detection system according to any one of claims 1 to 14:
detecting a first current value between a gate and a source of the driving transistor by the first current detection circuit;
detecting a voltage value between a drain and a source of the driving transistor by the voltage detection circuit;
detecting a second current value flowing through the drain and the source of the driving transistor by the second current detection circuit;
and calculating a capacitance value between the grid electrode and the source electrode of the driving transistor according to the first current value by the main controller, calculating a resistance value between the drain electrode and the source electrode of the driving transistor according to the voltage value and the second current value, and monitoring the aging progress of the driving transistor according to the capacitance value and the resistance value.
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Citations (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1089043A (en) * | 1992-09-21 | 1994-07-06 | 株式会社东芝 | Power transistor overcurrent protection circuit |
| CN102879967A (en) * | 2012-10-22 | 2013-01-16 | 深圳市华星光电技术有限公司 | Driving circuit of liquid crystal panel |
| JP2016131465A (en) * | 2015-01-14 | 2016-07-21 | 株式会社東芝 | Gate drive circuit |
| CN106168647A (en) * | 2016-05-27 | 2016-11-30 | 重庆大学 | IGBT ageing state detecting system |
| CN109425816A (en) * | 2017-08-16 | 2019-03-05 | 英飞凌科技股份有限公司 | Test MOS power switch |
| US20190101585A1 (en) * | 2017-09-29 | 2019-04-04 | Infineon Technologies Ag | Evaluating a gate-source leakage current in a transistor device |
| CN111044876A (en) * | 2020-01-19 | 2020-04-21 | 重庆大学 | IGBT module bonding wire state monitoring circuit and half-bridge structure monitoring circuit thereof |
| CN112147427A (en) * | 2019-06-29 | 2020-12-29 | 新疆金风科技股份有限公司 | Fault detection method and fault detection circuit of power module |
| CN113591336A (en) * | 2021-09-30 | 2021-11-02 | 中南大学 | Method and system for predicting service life of power supply IGBT module under passenger car |
| CN115561560A (en) * | 2022-10-21 | 2023-01-03 | 南京信息工程大学 | Pure hardware implementation control circuit and control method for power device aging test |
| CN115598485A (en) * | 2022-10-08 | 2023-01-13 | 南京信息工程大学（Cn） | Power tube aging test device of direct current solid-state circuit breaker and test method thereof |
-
2023
- 2023-07-31 CN CN202310944397.9A patent/CN116660715B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1089043A (en) * | 1992-09-21 | 1994-07-06 | 株式会社东芝 | Power transistor overcurrent protection circuit |
| CN102879967A (en) * | 2012-10-22 | 2013-01-16 | 深圳市华星光电技术有限公司 | Driving circuit of liquid crystal panel |
| JP2016131465A (en) * | 2015-01-14 | 2016-07-21 | 株式会社東芝 | Gate drive circuit |
| CN106168647A (en) * | 2016-05-27 | 2016-11-30 | 重庆大学 | IGBT ageing state detecting system |
| CN109425816A (en) * | 2017-08-16 | 2019-03-05 | 英飞凌科技股份有限公司 | Test MOS power switch |
| US20190101585A1 (en) * | 2017-09-29 | 2019-04-04 | Infineon Technologies Ag | Evaluating a gate-source leakage current in a transistor device |
| CN109596960A (en) * | 2017-09-29 | 2019-04-09 | 英飞凌科技股份有限公司 | Assess the gate-to-source leakage current in transistor device |
| CN112147427A (en) * | 2019-06-29 | 2020-12-29 | 新疆金风科技股份有限公司 | Fault detection method and fault detection circuit of power module |
| CN111044876A (en) * | 2020-01-19 | 2020-04-21 | 重庆大学 | IGBT module bonding wire state monitoring circuit and half-bridge structure monitoring circuit thereof |
| CN113591336A (en) * | 2021-09-30 | 2021-11-02 | 中南大学 | Method and system for predicting service life of power supply IGBT module under passenger car |
| CN115598485A (en) * | 2022-10-08 | 2023-01-13 | 南京信息工程大学（Cn） | Power tube aging test device of direct current solid-state circuit breaker and test method thereof |
| CN115561560A (en) * | 2022-10-21 | 2023-01-03 | 南京信息工程大学 | Pure hardware implementation control circuit and control method for power device aging test |
Non-Patent Citations (1)
| Title |
|---|
| 杨修杰 等: "一种MOS管自动功率老化测试系统的设计", 计算机测量与控制, no. 1, pages 46 - 48 * |
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