CN112505394A - Overcurrent detection method and device - Google Patents
Overcurrent detection method and device Download PDFInfo
- Publication number
- CN112505394A CN112505394A CN202011288690.7A CN202011288690A CN112505394A CN 112505394 A CN112505394 A CN 112505394A CN 202011288690 A CN202011288690 A CN 202011288690A CN 112505394 A CN112505394 A CN 112505394A
- Authority
- CN
- China
- Prior art keywords
- array
- current
- time point
- curve
- judgment time
- 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.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/165—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values
- G01R19/16528—Indicating that current or voltage is either above or below a predetermined value or within or outside a predetermined range of values using digital techniques or performing arithmetic operations
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention provides an overcurrent detection method and device, wherein multiple stages of judgment time points are extracted from an I2T curve, each judgment time point corresponds to one array respectively, the sum of all elements in the previous array is the unit of the square value of sampling current except the first array which takes the sampling period as the unit to store the square value of the sampling current, the sampling current value in each sampling period in the I2T curve does not need to be stored, and the data volume maintained in a sliding window corresponding to the I2T curve is greatly reduced. And only the updated array participates in the current overcurrent judgment, and the I2T curve integral overcurrent judgment in the prior art is replaced by the multi-stage judgment time point overcurrent judgment, so that the calculated amount of overcurrent detection is reduced. On the basis of realizing overcurrent detection in the meaning of I2T, the data storage capacity and the calculated amount are reduced, and the overcurrent detection efficiency is improved.
Description
Technical Field
The invention relates to the technical field of power electronics, in particular to an overcurrent detection method and device.
Background
In order to ensure the safety of the power electronic device, the power electronic control unit needs to quickly and efficiently detect whether the current is over-current, and takes protective measures quickly when the over-current is detected, so that the power electronic device is prevented from being burnt due to over-current.
The common overcurrent detection method is to judge whether overcurrent occurs according to the instantaneous current value, but the power electronic device actually has a certain short-time overload capacity and can bear the short-time current overcurrent, and if overcurrent judgment is carried out according to the instantaneous current value, the actual potential of the power electronic device cannot be exerted, so that the performance of the power electronic system is influenced.
At present, few power electronic control units adopt an overcurrent detection method in the meaning of I2T, which can ensure that a power electronic device is overloaded for a short time and exert the potential of the power electronic device, and can accurately judge when overcurrent protection needs to be carried out on the power electronic device, so that the power electronic control units adopt a corresponding overcurrent protection strategy in time, and the damage of the power electronic device is avoided.
A typical I2T curve is shown in fig. 1 as the SSPC (Solid-State Power Controller) tripping time curve, and the overcurrent detection in the sense of I2T is from the perspective of heat accumulation of Power electronics, and the detection rule is as follows: and calculating an integral value of the square of the collected current in any time segment, and judging that the current is overcurrent if the integral value is larger than a corresponding ordinate threshold value in the I2T curve.
The current overcurrent detection method in the meaning of I2T needs high-speed current collection, and needs to maintain a sliding window corresponding to the whole I2T curve, and is used for integral calculation of current squares in any time segment and comparison and judgment of an integral value and a corresponding threshold value. Because of high-speed current collection, huge current collection data are maintained in a sliding window corresponding to the whole I2T curve, taking a sampling period of 1ms and a sliding window corresponding to an I2T curve of 120s as an example, 120 x 1000 pieces of data need to be maintained, the data volume is huge, the requirement on storage space is high, and because the numerical value in the whole sliding window needs to be updated after each current collection, and then the updated data is used for calculating the integral value of the square of the collected current in any time segment, the calculation amount is large, and the overcurrent detection efficiency is low.
Disclosure of Invention
In view of this, the present invention provides an over-current detection method and apparatus, which, on the basis of implementing over-current detection in the meaning of I2T, require a small data storage space and a small calculation amount, and improve over-current detection efficiency.
In order to achieve the above purpose, the invention provides the following specific technical scheme:
an over-current detection method, comprising:
initializing an array set corresponding to an I2T curve, wherein each array in the array set corresponds to each level of judgment time point in the I2T curve respectively, the each level of judgment time point is calculated by starting point of the I2T curve, the next level of judgment time point is integral multiple of the previous level of judgment time point, the previous level of judgment time point is division value of the next level of judgment time point, the ratio of the time length corresponding to each level of judgment time point in the each level of judgment time point to the division value of the level of judgment time point is the same as the length of the corresponding array, and the length of the first array is the ratio of the time length corresponding to the first level of judgment time point to the sampling period;
in the I2T curve descending segment, updating the loop iteration sub in the first array in the array set according to the acquisition current in each sampling period, wherein each array adopts the position of the current updating element of the loop iteration sub table in the array;
sequentially judging whether each array is updated or not; for each array, updating after the loop iteration sub-loop of the previous array is updated for one round, and updating the loop iteration sub-loop of the array into the sum of all current elements of the previous array;
if the array is updated, judging whether the sum of all elements in the array is larger than the threshold corresponding to the array;
under the condition that the sum value of all elements in the updated array is not larger than the corresponding threshold value of the array, judging that the current is not overcurrent;
and judging that the current is overcurrent under the condition that the sum value of all elements in any array is greater than the threshold value corresponding to the array after the update of the array.
Optionally, the method further includes:
acquiring the instantaneous current value of the electronic device in the switching period at the cross section of the I2T curve;
determining that the current is over-current if the instantaneous current value is greater than an instantaneous current threshold.
Optionally, the updating, in each sampling period, the loop iteration sub in the first array in the array set according to the acquisition current includes:
and updating the loop iteration sub-in the first array in the array set to be the square value of the acquisition current of the sampling period in each sampling period.
Optionally, the updating the loop iteration sub-of the array to the sum of all current elements of the previous array includes:
determining the difference between the sum of all elements before the last element in the previous array is updated and the difference before and after the last element is updated as the sum of all current elements in the previous array;
and updating the loop iteration sub of the array to the sum of all current elements of the previous array.
Optionally, the threshold corresponding to each array is L1*L2*…*LN*I2*Yk 2；
LkThe length of the kth array in the array set is k ═ 1, 2.. times.n, where N is the number of arrays in the array set;
i is rated current;
Ykand the ordinate corresponding to the k-th judging time point in the I2T curve.
An overcurrent detecting apparatus comprising:
the device comprises an array set initialization unit, a sampling unit and a sampling unit, wherein the array set initialization unit is used for initializing an array set corresponding to an I2T curve, each array in the array set corresponds to each stage of judgment time point in the I2T curve respectively, the each stage of judgment time point starts to be calculated by using the starting point of the I2T curve, the next stage of judgment time point is integral multiple of the previous stage of judgment time point, the previous stage of judgment time point is the division value of the next stage of judgment time point, the ratio of the time length corresponding to each stage of judgment time point in the each stage of judgment time point to the division value of the stage of judgment time point is the same as the length of the corresponding array, and the length of the first array is the ratio of the time length corresponding to the;
the array updating unit is used for updating the loop iteration sub in the first array in the array set according to the acquired current in each sampling period at the descending stage of the curve I2T, and each array adopts the position of the current updating element of the loop iteration sub table in the array;
the updating judgment unit is used for sequentially judging whether each array is updated or not; for each array, updating after the loop iteration sub-loop of the previous array is updated for one round, and updating the loop iteration sub-loop of the array into the sum of all current elements of the previous array;
the first overcurrent judging unit is used for judging whether the sum of all elements in the array is larger than the threshold corresponding to the array when the array is updated; under the condition that the sum value of all elements in the updated array is not larger than the corresponding threshold value of the array, judging that the current is not overcurrent; and judging that the current is overcurrent under the condition that the sum value of all elements in any array is greater than the threshold value corresponding to the array after the update of the array.
Optionally, the apparatus further includes a second overcurrent determining unit, specifically configured to:
acquiring the instantaneous current value of the electronic device in the switching period at the cross section of the I2T curve;
determining that the current is over-current if the instantaneous current value is greater than an instantaneous current threshold.
Optionally, the array updating unit is specifically configured to:
and updating the loop iteration sub-in the first array in the array set to be the square value of the acquisition current of the sampling period in each sampling period.
Optionally, the update determining unit is specifically configured to:
determining the difference between the sum of all elements before the last element in the previous array is updated and the difference before and after the last element is updated as the sum of all current elements in the previous array;
and updating the loop iteration sub of the array to the sum of all current elements of the previous array.
Optionally, the threshold corresponding to each array is L1*L2*…*LN*I2*Yk 2；
LkThe length of the kth array in the array set is k ═ 1, 2.. times.n, where N is the number of arrays in the array set;
i is rated current;
Ykand the ordinate corresponding to the k-th judging time point in the I2T curve.
Compared with the prior art, the invention has the following beneficial effects:
the invention discloses an overcurrent detection method, which extracts multi-stage judgment time points from an I2T curve, wherein the next stage judgment time point is integral multiple of the previous stage judgment time point, the previous stage judgment time point is a division value of the next stage judgment time point, each judgment time point corresponds to an array, the ratio of the time length corresponding to each stage judgment time point in each stage judgment time point to the division value of the stage judgment time point is the same as the length of the corresponding array, the cycle iteration sub in the first array is updated according to the collected current in each sampling period at the descending stage of the I2T curve, and for each array, the cycle iteration sub is updated after the cycle iteration sub-cycle of the previous array is updated, and the cycle iteration sub of the array is updated to the sum of all current elements of the previous array. That is, except for the first array storing the square value of the sampling current in sampling period unit, the other arrays store the square value of the sampling current in the unit of the sum of all elements in the previous array, the value of the sampling current in each sampling period in the I2T curve does not need to be stored, and the calculation amount is small while the data amount maintained in the sliding window corresponding to the I2T curve is greatly reduced by adopting multi-level recursive summation and fast summation based on the loop iteration sub-. And only the updated array participates in the current overcurrent judgment, that is, the current overcurrent judgment of the I2T curve in the prior art is replaced by the multistage judgment time point overcurrent judgment, so that a large amount of calculation caused by the overcurrent judgment of the current data corresponding to each time segment in each sampling period by the conventional overcurrent detection method in the I2T sense is avoided, the calculated amount of overcurrent detection is greatly reduced, the data storage amount and the calculated amount are reduced on the basis of realizing the overcurrent detection in the I2T sense, and the overcurrent detection efficiency is improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is a schematic diagram of a typical I2T curve;
fig. 2 is a schematic flow chart of an over-current detection method according to an embodiment of the present invention;
fig. 3 is a schematic flow chart of another over-current detection method disclosed in the embodiment of the present invention;
fig. 4 is a schematic structural diagram of an over-current detection device according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In order to reduce data storage capacity and calculation amount on the basis of implementing overcurrent detection in the meaning of I2T, the embodiment discloses an overcurrent detection method, which is applied to a power electronic control unit, where the electronic control unit can be implemented based on an arm (advanced RISC machines) processor, a DSP (Digital signal processing) processor, an FPGA (Field Programmable Gate Array) processor, and the like, and please refer to fig. 2, the overcurrent detection method includes the following steps:
s101: initializing an array set corresponding to an I2T curve, wherein each array in the array set respectively corresponds to each level of judgment time point in the I2T curve, the judgment time points of each level are calculated from the starting point of the I2T curve, the judgment time point of the next level is integral multiple of the judgment time point of the previous level, the judgment time point of the previous level is a division value of the judgment time point of the next level, the ratio of the time length corresponding to each level of judgment time point in the judgment time points of each level to the division value of the judgment time point of the level is the same as the length of the corresponding array, and the length of the first array is the ratio of the time length corresponding to the first level of judgment time point to the sampling period.
It can be understood that the more the judgment time points, the higher the accuracy of the overcurrent judgment, and the larger the data storage amount and the calculation amount, and conversely, the less the judgment time points, the lower the accuracy of the overcurrent judgment, and the smaller the data storage amount and the calculation amount. Therefore, each stage of judgment points in the I2T curve can be preset according to the actual overcurrent judgment precision requirement, the data storage amount and the calculation amount requirement. It should be noted that the time length corresponding to each stage of judgment time point is not a time interval between adjacent stages of judgment time points, but an accumulated time length counted from the same starting time. The time length corresponding to the first-level judgment time is within the coordinate range of the horizontal line segment of the I2T curve.
The judging time points of each stage are calculated from the starting point of the I2T curve, and the judging time point of the later stage is integral multiple of the judging time point of the previous stage. In one embodiment, the sampling period may be a millisecond-scale period, such as 1ms, the first-stage determination time point is 125ms, the second-stage determination time point is 1s, the third-stage determination time point is 5s, the fourth-stage determination time point is 30s, and the fifth-stage determination time point is 120s, but not limited thereto. For example, the sampling period is 1ms, the first-stage determination time point is 150ms, the second-stage determination time point is 1.5s, the third-stage determination time point is 9s, the fourth-stage determination time point is 36s, and the fifth-stage determination time point is 108 s.
Each array in the array set corresponds to each level of judgment time point in the I2T curve, the previous level of judgment time point is the division value of the next level of judgment time point, the ratio of the time length corresponding to each level of judgment time point in each level of judgment time point to the division value of the level of judgment time point is the same as the length of the corresponding array, the length of the first array is the ratio of the time length corresponding to the first level of judgment time point to the sampling period, and the value of the element in each array in the array set is 0 in the initial state. Taking the fifth-level determination time point as an example, the length of the first array is 125, the length of the second array is 8, the length of the third array is 5, the length of the fourth array is 6, and the length of the fifth array is 4, and the array set disclosed in this embodiment does not need to store the sampling current value in each sampling period in the I2T curve, thereby greatly reducing the data amount maintained in the sliding window corresponding to the I2T curve.
S102: and in the I2T curve descending segment, updating the loop iteration child in the first array in the array set according to the acquisition current in each sampling period, wherein each array adopts the position of the current updating element in the loop iteration child table in the array.
Specifically, taking the fifth-stage judgment time point as an example, after the sampling current value is obtained for the first time, the first element in the first array is updated, after the sampling current value is obtained for the second time, the second element in the first array is updated … …, after the sampling current value is obtained for the 125 th time, the last element in the first array is updated, and after the sampling current value is obtained for the 126 th time, the first element in the first array is updated. That is, for each array, when the last element is updated, the next update is performed from the first element, and for each array, the update is sequentially circulated from the first element to the last element.
S103: sequentially judging whether each array is updated or not; for each array, updating occurs after one round of the loop iteration sub-loop updating of the previous array, and the loop iteration sub-loop updating of the array is updated to the sum of all current elements of the previous array.
And when the last element in the first array is updated, updating the loop iteration sub in the second array to the sum of all elements in the first array, and when the last element in the second array is updated, updating the loop iteration sub in the third array to the sum of all elements in the second array, and so on.
Further, in order to improve the efficiency of calculating the sum of all loop iteration sub-loops in the array, in this embodiment, a fast calculation method is provided, where for each array, the update occurs after the loop iteration sub-loop of the previous array is updated for one round, and the loop iteration sub-loop of the array is updated to be the sum of all current elements in the previous array, specifically, the difference between the sum of all current elements in the previous array before the last element is updated and the difference before and after the last element is updated is determined to be the sum of all current elements in the previous array. In other words, the sum of all the elements before the last element in the previous array is summed with the updated element change value, which is equal to the value after the last element is updated minus the value before the last element is updated, to determine the sum as the sum of all the current elements in the previous array. Of course, in other embodiments, the sum of all elements of the array may be calculated after each update of the array.
S104: and judging whether the sum of all elements in the array subjected to updating is larger than the threshold corresponding to the array.
Taking the above five-stage judgment time point as an example, the first array is updated every sampling period, the second array is updated every 125 sampling periods, the third array is updated every 125 × 8 sampling periods, the fourth array is updated every 125 × 8 × 5 sampling periods, and the fifth array is updated every 125 × 8 × 5 sampling periods.
That is to say, the first array performs overcurrent judgment every sampling period, the second array performs overcurrent judgment every 125 sampling periods, the third array performs overcurrent judgment every 125 × 8 sampling periods, the fourth array performs overcurrent judgment every 125 × 8 × 5 sampling periods, and the fifth array performs overcurrent judgment every 125 × 8 × 5 sampling periods, so that a large amount of calculations caused by overcurrent judgment on current data corresponding to each time segment in each sampling period by the conventional overcurrent detection method in the sense of I2T are avoided, and the calculation amount of overcurrent detection is greatly reduced.
Wherein, the corresponding threshold value of each array is L1*L2*…*LN*I2*Yk 2；
LkThe number of loop iterators in the kth array in the sampling current array set is k ═ 1, 2.. multidot.n, and N is the number of arrays in the sampling current array set;
i is rated current;
Ykand is the ordinate corresponding to the upper limit value of the kth judgment time interval in the curve I2T.
If the sum of all elements in the updated array is not greater than the threshold corresponding to the array, S105 is executed: the current is determined to be not overcurrent.
That is, in the case where the sum of all elements in the array where the update occurs is not greater than the threshold corresponding to the array, it is determined that no current overcurrent has occurred.
When the sum of all elements in any array is greater than the threshold corresponding to the array after the update of the array, S106 is executed: and judging that the current is over-current.
It can be seen that, in the overcurrent detection method disclosed in this embodiment, multiple stages of determination time points are extracted from the I2T curve, each determination time point corresponds to one array, and except that the first array stores the square value of the sampling current in a unit of a sampling period, the sum of all elements in the previous array stores the square value of the sampling current in a unit of the sum of all elements in the previous array, so that the value of the sampling current in each sampling period in the I2T curve does not need to be stored, and the data amount maintained in the sliding window corresponding to the I2T curve is greatly reduced. And only the updated array participates in the current overcurrent judgment, and the I2T curve integral overcurrent judgment in the prior art is replaced by the multi-stage judgment time point overcurrent judgment, so that the calculated amount of overcurrent detection is reduced. On the basis of realizing overcurrent detection in the meaning of I2T, the data storage capacity and the calculated amount are reduced, and the overcurrent detection efficiency is improved.
Further, in order to simultaneously determine whether to perform overcurrent according to the instantaneous current value and perform overcurrent detection in the meaning of I2T, the embodiment discloses another overcurrent detection method, please refer to fig. 3, which specifically includes the following steps:
s201: initializing an array set corresponding to an I2T curve, wherein each array in the array set respectively corresponds to each level of judgment time point in the I2T curve, the judgment time points of each level are calculated from the starting point of the I2T curve, the judgment time point of the next level is integral multiple of the judgment time point of the previous level, the judgment time point of the previous level is a division value of the judgment time point of the next level, the ratio of the time length corresponding to each level of judgment time point in the judgment time points of each level to the division value of the judgment time point of the level is the same as the length of the corresponding array, and the length of the first array is the ratio of the time length corresponding to the first level of judgment time point to the sampling period.
S202: and acquiring the instantaneous current value in the switching period of the electronic device in the cross section of the I2T curve.
Wherein the switching period of the electronic device is less than the sampling period.
S203: it is determined whether the instantaneous current value is greater than the instantaneous current threshold.
In one embodiment, the instantaneous current threshold may be 6 times the rated current. Of course, in other embodiments, the instantaneous current threshold may be 5 times, 7 times, etc. of the rated current, or even a non-integer multiple, where the specific multiple is determined by the characteristics of the electronic device itself, and may be an empirical value or a calibrated value.
If yes, S204: and judging that the current is over-current.
If not, S205: and in the I2T curve descending segment, updating the loop iteration child in the first array in the array set according to the acquisition current in each sampling period, wherein each array adopts the position of the current updating element in the loop iteration child table in the array.
S206: sequentially judging whether each array is updated or not; for each array, updating occurs after one round of the loop iteration sub-loop updating of the previous array, and the loop iteration sub-loop updating of the array is updated to the sum of all current elements of the previous array.
S207: and judging whether the sum of all elements in the array subjected to updating is larger than the threshold corresponding to the array.
If the sum of all elements in the updated array is not greater than the threshold corresponding to the array, S208 is executed: the current is determined to be not overcurrent.
And executing S204 when the sum of all elements in any array is greater than the threshold corresponding to the array after the update of the array.
Based on the over-current detection method disclosed in the above embodiments, the present embodiment correspondingly discloses an over-current detection device, please refer to fig. 4, and the over-current detection device includes:
the array set initialization unit 100 is configured to initialize an array set corresponding to an I2T curve, where each array in the array set corresponds to each stage of judgment time point in the I2T curve, the each stage of judgment time point is calculated from a starting point of the I2T curve, a next stage of judgment time point is an integer multiple of a previous stage of judgment time point, the previous stage of judgment time point is a division value of the next stage of judgment time point, a ratio of a time length corresponding to each stage of judgment time point in the each stage of judgment time point to the division value of the stage of judgment time point is the same as a length of the corresponding array, and the length of the first array is a ratio of a time length corresponding to the first stage of judgment time point to a sampling period;
the array updating unit 200 is configured to update the loop iteration sub in the first array in the array set according to the acquired current in each sampling period at the I2T curve descending stage, where each array uses the position of the current updating element in the loop iteration sub table in the array;
an update determining unit 300, configured to sequentially determine whether each array is updated; for each array, updating after the loop iteration sub-loop of the previous array is updated for one round, and updating the loop iteration sub-loop of the array into the sum of all current elements of the previous array;
a first overcurrent determining unit 400, configured to determine, when an array is updated, whether a sum of all elements in the array is greater than a threshold corresponding to the array; under the condition that the sum value of all elements in the updated array is not larger than the corresponding threshold value of the array, judging that the current is not overcurrent; and judging that the current is overcurrent under the condition that the sum value of all elements in any array is greater than the threshold value corresponding to the array after the update of the array.
Optionally, the apparatus further includes a second overcurrent determining unit, specifically configured to:
acquiring the instantaneous current value of the electronic device in the switching period at the cross section of the I2T curve;
determining that the current is over-current if the instantaneous current value is greater than an instantaneous current threshold.
Optionally, the array updating unit 200 is specifically configured to:
and updating the loop iteration sub-in the first array in the array set to be the square value of the acquisition current of the sampling period in each sampling period.
Optionally, the update determining unit 300 is specifically configured to:
determining the difference between the sum of all elements before the last element in the previous array is updated and the difference before and after the last element is updated as the sum of all current elements in the previous array;
and updating the loop iteration sub of the array to the sum of all current elements of the previous array.
Optionally, the threshold corresponding to each array is L1*L2*…*LN*I2*Yk 2；
LkThe length of the kth array in the array set is k ═ 1,2, …, N, where N is the number of arrays in the array set;
i is rated current;
Ykand the ordinate corresponding to the k-th judging time point in the I2T curve.
In the over-current detection device disclosed in this embodiment, a plurality of stages of judgment time points are extracted from an I2T curve, a next stage of judgment time point is an integral multiple of a previous stage of judgment time point, the previous stage of judgment time point is a division value of the next stage of judgment time point, each judgment time point corresponds to an array, a ratio of a time length corresponding to each stage of judgment time point in each stage of judgment time point to the division value of the stage of judgment time point is the same as the length of the corresponding array, at a descending stage of the I2T curve, a loop iteration sub in a first array is updated according to an acquisition current in each sampling period, for each array, the update occurs after a loop iteration sub-loop of the previous array is updated, and the loop iteration sub of the array is updated to a sum of all current elements of the previous array. That is, except for the first array storing the square value of the sampling current in sampling period unit, the other arrays store the square value of the sampling current in the unit of the sum of all elements in the previous array, the value of the sampling current in each sampling period in the I2T curve does not need to be stored, and the calculation amount is small while the data amount maintained in the sliding window corresponding to the I2T curve is greatly reduced by adopting multi-level recursive summation and fast summation based on the loop iteration sub-. And only the updated array participates in the current overcurrent judgment, that is, the current overcurrent judgment of the I2T curve in the prior art is replaced by the multistage judgment time point overcurrent judgment, so that a large amount of calculation caused by the overcurrent judgment of the current data corresponding to each time segment in each sampling period by the conventional overcurrent detection method in the I2T sense is avoided, the calculated amount of overcurrent detection is greatly reduced, the data storage amount and the calculated amount are reduced on the basis of realizing the overcurrent detection in the I2T sense, and the overcurrent detection efficiency is improved.
The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.
It is further noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in Random Access Memory (RAM), memory, Read Only Memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (10)
1. An over-current detection method, comprising:
initializing an array set corresponding to an I2T curve, wherein each array in the array set corresponds to each level of judgment time point in the I2T curve respectively, the each level of judgment time point is calculated by starting point of the I2T curve, the next level of judgment time point is integral multiple of the previous level of judgment time point, the previous level of judgment time point is division value of the next level of judgment time point, the ratio of the time length corresponding to each level of judgment time point in the each level of judgment time point to the division value of the level of judgment time point is the same as the length of the corresponding array, and the length of the first array is the ratio of the time length corresponding to the first level of judgment time point to the sampling period;
in the I2T curve descending segment, updating the loop iteration sub in the first array in the array set according to the acquisition current in each sampling period, wherein each array adopts the position of the current updating element of the loop iteration sub table in the array;
sequentially judging whether each array is updated or not; for each array, updating after the loop iteration sub-loop of the previous array is updated for one round, and updating the loop iteration sub-loop of the array into the sum of all current elements of the previous array;
if the array is updated, judging whether the sum of all elements in the array is larger than the threshold corresponding to the array;
under the condition that the sum value of all elements in the updated array is not larger than the corresponding threshold value of the array, judging that the current is not overcurrent;
and judging that the current is overcurrent under the condition that the sum value of all elements in any array is greater than the threshold value corresponding to the array after the update of the array.
2. The method of claim 1, further comprising:
acquiring the instantaneous current value of the electronic device in the switching period at the cross section of the I2T curve;
determining that the current is over-current if the instantaneous current value is greater than an instantaneous current threshold.
3. The method of claim 1, wherein updating the loop iteration subset in the first array of the array set according to the acquisition current at each sampling period comprises:
and updating the loop iteration sub-in the first array in the array set to be the square value of the acquisition current of the sampling period in each sampling period.
4. The method of claim 1, wherein sub-updating the loop iteration of the array to the sum of all current elements of the previous array comprises:
determining the difference between the sum of all elements before the last element in the previous array is updated and the difference before and after the last element is updated as the sum of all current elements in the previous array;
and updating the loop iteration sub of the array to the sum of all current elements of the previous array.
5. The method of claim 1, wherein the threshold value for each array is L1*L2*…*LN*I2*Yk 2；
LkThe length of the kth array in the array set is k ═ 1, 2.. times.n, where N is the number of arrays in the array set;
i is rated current;
Ykand the ordinate corresponding to the k-th judging time point in the I2T curve.
6. An overcurrent detection apparatus, comprising:
the device comprises an array set initialization unit, a sampling unit and a sampling unit, wherein the array set initialization unit is used for initializing an array set corresponding to an I2T curve, each array in the array set corresponds to each stage of judgment time point in the I2T curve respectively, the each stage of judgment time point starts to be calculated by using the starting point of the I2T curve, the next stage of judgment time point is integral multiple of the previous stage of judgment time point, the previous stage of judgment time point is the division value of the next stage of judgment time point, the ratio of the time length corresponding to each stage of judgment time point in the each stage of judgment time point to the division value of the stage of judgment time point is the same as the length of the corresponding array, and the length of the first array is the ratio of the time length corresponding to the;
the array updating unit is used for updating the loop iteration sub in the first array in the array set according to the acquired current in each sampling period at the descending stage of the curve I2T, and each array adopts the position of the current updating element of the loop iteration sub table in the array;
the updating judgment unit is used for sequentially judging whether each array is updated or not; for each array, updating after the loop iteration sub-loop of the previous array is updated for one round, and updating the loop iteration sub-loop of the array into the sum of all current elements of the previous array;
the first overcurrent judging unit is used for judging whether the sum of all elements in the array is larger than the threshold corresponding to the array when the array is updated; under the condition that the sum value of all elements in the updated array is not larger than the corresponding threshold value of the array, judging that the current is not overcurrent; and judging that the current is overcurrent under the condition that the sum value of all elements in any array is greater than the threshold value corresponding to the array after the update of the array.
7. The apparatus according to claim 6, further comprising a second over-current determining unit, specifically configured to:
acquiring the instantaneous current value of the electronic device in the switching period at the cross section of the I2T curve;
determining that the current is over-current if the instantaneous current value is greater than an instantaneous current threshold.
8. The apparatus of claim 6, wherein the array update unit is specifically configured to:
and updating the loop iteration sub-in the first array in the array set to be the square value of the acquisition current of the sampling period in each sampling period.
9. The apparatus according to claim 6, wherein the update determining unit is specifically configured to:
determining the difference between the sum of all elements before the last element in the previous array is updated and the difference before and after the last element is updated as the sum of all current elements in the previous array;
and updating the loop iteration sub of the array to the sum of all current elements of the previous array.
10. The apparatus of claim 6, wherein the threshold value for each array is L1*L2*…*LN*I2*Yk 2；
LkThe length of the kth array in the array set is k ═ 1, 2.. times.n, where N is the number of arrays in the array set;
i is rated current;
Ykand the ordinate corresponding to the k-th judging time point in the I2T curve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011288690.7A CN112505394B (en) | 2020-11-17 | 2020-11-17 | Overcurrent detection method and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011288690.7A CN112505394B (en) | 2020-11-17 | 2020-11-17 | Overcurrent detection method and device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112505394A true CN112505394A (en) | 2021-03-16 |
| CN112505394B CN112505394B (en) | 2022-09-20 |
Family
ID=74956630
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011288690.7A Active CN112505394B (en) | 2020-11-17 | 2020-11-17 | Overcurrent detection method and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112505394B (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080165461A1 (en) * | 2007-01-05 | 2008-07-10 | Namwook Paik | System and method for circuit overcurrent protection |
| CN103414150A (en) * | 2013-08-23 | 2013-11-27 | 上海新时达电气股份有限公司 | Inverse time limit protection method |
| US20150057822A1 (en) * | 2013-08-26 | 2015-02-26 | Micropac Industries, Inc. | Power controller |
| CN105940582A (en) * | 2014-01-20 | 2016-09-14 | 罗伯特·博世有限公司 | Overload monitoring device and method for monitoring overload |
| CN106370922A (en) * | 2016-08-31 | 2017-02-01 | 中国科学院空间应用工程与技术中心 | Solid state power controller and fault current record method |
| CN107346965A (en) * | 2017-07-18 | 2017-11-14 | 深圳市航天新源科技有限公司 | Possesses the current limliting time delayed turn-off on-off circuit of the repeatable triggering of excessively stream memory function |
-
2020
- 2020-11-17 CN CN202011288690.7A patent/CN112505394B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20080165461A1 (en) * | 2007-01-05 | 2008-07-10 | Namwook Paik | System and method for circuit overcurrent protection |
| CN103414150A (en) * | 2013-08-23 | 2013-11-27 | 上海新时达电气股份有限公司 | Inverse time limit protection method |
| US20150057822A1 (en) * | 2013-08-26 | 2015-02-26 | Micropac Industries, Inc. | Power controller |
| CN105940582A (en) * | 2014-01-20 | 2016-09-14 | 罗伯特·博世有限公司 | Overload monitoring device and method for monitoring overload |
| US20160356827A1 (en) * | 2014-01-20 | 2016-12-08 | Robert Bosch Gmbh | Overload monitoring device and method for overload monitoring |
| CN106370922A (en) * | 2016-08-31 | 2017-02-01 | 中国科学院空间应用工程与技术中心 | Solid state power controller and fault current record method |
| CN107346965A (en) * | 2017-07-18 | 2017-11-14 | 深圳市航天新源科技有限公司 | Possesses the current limliting time delayed turn-off on-off circuit of the repeatable triggering of excessively stream memory function |
Non-Patent Citations (5)
| Title |
|---|
| 刘超等: "KGG-1M型固体功率控制器", 《机电元件》 * |
| 解伟等: "基于LabView的交直流智能接触器(EMPC)测试系统设计", 《计算机测量与控制》 * |
| 郑志洪等: "基于FPGA的直流固态功率控制器的设计", 《机电元件》 * |
| 阮立刚等: "基于混合信号状态机的交流固态功率控制器功能模型", 《航空学报》 * |
| 马海君等: "智能断路器的保护作用与实现方法探析", 《科技信息》 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112505394B (en) | 2022-09-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104466277A (en) | Self-discharging screening method of lithium ion battery | |
| CN112505394B (en) | Overcurrent detection method and device | |
| EP3065066A1 (en) | Method and device for calculating degree of similarity between files pertaining to different fields | |
| CN105698815B (en) | Count the adjusting method and device of step data | |
| US20100097133A1 (en) | Signal Processing | |
| CN110544039A (en) | Method and device for identifying shadow occlusion of photovoltaic string | |
| EP3014722A1 (en) | Adaptive arc fault detection trip decision buffer | |
| CN110618387B (en) | Lithium battery failure analysis method and device, electronic equipment and storage medium | |
| CN117233645B (en) | Energy storage inverter battery abnormality judging method, system and medium | |
| Ninagawa | Power spectral analysis of elementary cellular automata | |
| CN108983034B (en) | Internal short circuit detection method and device | |
| EP3570398A1 (en) | Method and apparatus for determining a direction of an intermittent grounding fault in a power grid | |
| CN111245367B (en) | IV curve acquisition method and device and related components | |
| CN109816165A (en) | Wind-powered electricity generation ultra-short term power forecasting method and system | |
| CN111707295A (en) | Method and device for treating temperature drift | |
| CN113359028B (en) | Motor operation detection method and device, storage medium and electronic equipment | |
| CN108008183B (en) | Electric quantity measuring method, system, equipment and computer storage medium | |
| CN114818907A (en) | State monitoring method, device and equipment of power transmission line and storage medium | |
| CN108696955B (en) | Pot dry-cooking judgment method and device for electric cooker and electric cooker | |
| CN116008836A (en) | Short circuit detection method and device for battery and storage medium | |
| CN110134048B (en) | Alarm method, alarm device, storage medium and processor | |
| CN114872554A (en) | Fault processing method and device of battery module, electronic equipment and storage medium | |
| CN107576840B (en) | Phase shifter load identification method and device and power utilization protection system | |
| CN107797031B (en) | Arc fault detection method and device | |
| CN107783013A (en) | A kind of detection method and device of arc fault |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |