CN114167970A - Overcurrent protection method and related assembly - Google Patents
Overcurrent protection method and related assembly Download PDFInfo
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- CN114167970A CN114167970A CN202111501616.3A CN202111501616A CN114167970A CN 114167970 A CN114167970 A CN 114167970A CN 202111501616 A CN202111501616 A CN 202111501616A CN 114167970 A CN114167970 A CN 114167970A
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- 238000000034 method Methods 0.000 title claims abstract description 44
- 238000004590 computer program Methods 0.000 claims description 11
- 238000010586 diagram Methods 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 230000000630 rising effect Effects 0.000 description 2
- 238000001914 filtration Methods 0.000 description 1
- 230000016507 interphase Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000011897 real-time detection Methods 0.000 description 1
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F1/00—Details not covered by groups G06F3/00 - G06F13/00 and G06F21/00
- G06F1/26—Power supply means, e.g. regulation thereof
- G06F1/30—Means for acting in the event of power-supply failure or interruption, e.g. power-supply fluctuations
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F1/00—Details not covered by groups G06F3/00 - G06F13/00 and G06F21/00
- G06F1/04—Generating or distributing clock signals or signals derived directly therefrom
- G06F1/08—Clock generators with changeable or programmable clock frequency
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H1/00—Details of emergency protective circuit arrangements
- H02H1/0007—Details of emergency protective circuit arrangements concerning the detecting means
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/10—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers
- H02H7/12—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/10—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers
- H02H7/12—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers
- H02H7/1216—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for converters; for rectifiers for static converters or rectifiers for AC-AC converters
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M1/00—Details of apparatus for conversion
- H02M1/32—Means for protecting converters other than automatic disconnection
Abstract
The invention discloses an overcurrent protection method and a related component, in the scheme, because an overcurrent protection device is used for outputting an overcurrent protection signal when detecting that the input current of the overcurrent protection device is larger than an overcurrent protection value, specifically, when the overcurrent time is shorter and is not larger than the preset overcurrent time, the overcurrent protection signal can be judged to be output because the overcurrent protection device is interfered, at the moment, a frequency converter can normally work, otherwise, the overcurrent protection signal is output because of the fault overcurrent output of the frequency converter, at the moment, the frequency converter is required to be controlled to stop outputting, so that the frequency converter and a load are prevented from being burnt. In summary, in the present application, the magnitude of the overcurrent time when the overcurrent protection device outputs the overcurrent protection signal is compared with the preset overcurrent time to determine whether the overcurrent protection device outputs the overcurrent protection signal due to detecting the fault of the frequency converter or due to the interference, so as to perform corresponding control, and avoid the control of stopping the frequency converter due to the error caused by the interference.
Description
Technical Field
The present invention relates to the field of circuit protection, and in particular, to an overcurrent protection method and related components.
Background
The frequency converter is a device integrating rectification (alternating current to direct current), filtering, inversion (direct current to alternating current), a brake unit, a drive unit, a detection unit and a micro-processing unit, and can provide required voltage for the load according to the actual requirement of the load.
The frequency converter in the prior art is usually provided with an overcurrent protection device, which mainly samples an output current signal of the frequency converter, compares the output current signal with an overcurrent protection threshold value, and outputs the overcurrent protection signal to a processor for controlling the frequency converter if the output current signal of the frequency converter is greater than the overcurrent protection threshold value, so that the processor controls the frequency converter to stop working, and the frequency converter and a load are prevented from being burnt out due to overcurrent output of the frequency converter.
However, in order to enable the overcurrent protection device to respond in time to output an overcurrent protection signal and immediately stop the operation of the frequency converter when the current suddenly increases in a short time (microsecond or millisecond level), such as an inter-phase short circuit, a ground short circuit, and the like, the overcurrent protection device is required to have a fast response speed, so that the overcurrent protection device is sensitive, and therefore the overcurrent protection device is easily interfered to generate false alarm, and the frequency converter cannot normally operate.
Therefore, how to improve an effective and accurate over-current protection method is an urgent problem to be solved.
Disclosure of Invention
The invention aims to provide an overcurrent protection method and a related component, wherein the overcurrent time of an overcurrent protection signal output by an overcurrent protection device is compared with the preset overcurrent time to judge whether the overcurrent protection device outputs the overcurrent protection signal due to the detection of the fault overcurrent output of a frequency converter or the self interference, so that the corresponding control is carried out, and the control of stopping the frequency converter due to the error caused by the interference is avoided.
In order to solve the above technical problem, the present invention provides an overcurrent protection method, wherein an input terminal of an overcurrent protection device is connected to an output terminal of a frequency converter, and is configured to output an overcurrent protection signal when detecting that a self input current is greater than an overcurrent protection value, and output an overcurrent stop signal when detecting that the self input current is not greater than the overcurrent protection value, the method including:
determining the overcurrent time of the overcurrent protection device for outputting the overcurrent protection signal based on the overcurrent protection signal and the overcurrent stop signal;
judging whether the overcurrent time is greater than preset overcurrent time or not;
if so, judging the fault overcurrent output of the frequency converter, and controlling the frequency converter to stop outputting;
if not, judging that the overcurrent protection device is interfered, and controlling the frequency converter to continue working.
Preferably, determining the overcurrent time of the overcurrent protection device outputting the overcurrent protection signal based on the overcurrent protection signal and the overcurrent stop signal includes:
s201: initializing the accumulated clock count value to be 0;
s202: when the overcurrent protection signal is received, recording a first current count value of a system clock, marking the position of an overcurrent mark as 1, and marking the position of an overcurrent cycle as 1;
s203: when the overcurrent stop signal is received, recording a second current count value of the system clock, positioning the overcurrent flag at 0, and updating the accumulated clock count value based on a difference value obtained by subtracting the first current count value from the second current count value;
s204: when receiving the over-current determination signal, determining whether the over-current period flag bit is 1, if so, entering step S205, and if not, entering step S209;
s205: judging whether the over-current flag bit is 1, if so, entering step S206, and if not, entering step S207;
s206: updating the accumulated clock count value based on a difference value obtained by subtracting the first current count value from a third current count value of the system clock and the accumulated clock count value before updating;
s207: judging whether the updated accumulated clock count value is larger than a preset over-current accumulated count value or not, and if not, entering the step S208;
s208: initializing the flag bit of the overcurrent cycle to be 0, controlling the frequency converter to restart, and returning to the step S202;
s29: judging whether the overcurrent protection signal is not received after a preset time since the overcurrent stop signal is received last time, if so, entering the step S210;
s210: and multiplying the updated accumulated clock count value by the period of the system clock to set the updated accumulated clock count value as the overcurrent time.
Preferably, after determining whether the updated accumulated clock count value is greater than a preset overcurrent accumulated count value, the method further includes:
if yes, initializing the overcurrent cycle flag bit to be 0, judging the fault overcurrent output of the frequency converter, and controlling the frequency converter to stop outputting.
Preferably, after the updated accumulated clock count value is multiplied by the period of the system clock and is set as the overcurrent time, the method further includes:
and entering a step of judging whether the overcurrent time is greater than preset overcurrent time.
Preferably, after determining whether the overcurrent protection signal is not received after a preset time elapses since the overcurrent stop signal is received last time, the method further includes:
if not, returning to the step of recording the first current count value of the system clock, marking the position 1 of the overcurrent flag, and marking the position 1 of the overcurrent cycle when the overcurrent protection signal is received.
In order to solve the above technical problem, the present invention provides an overcurrent protection system, in which an overcurrent protection device is configured to output an overcurrent protection signal when detecting that its own input current is greater than an overcurrent protection value, and to stop outputting the overcurrent protection signal when detecting that its own input current is not greater than the overcurrent protection value, the system including:
the determining unit is used for determining the overcurrent time of the overcurrent protection device for outputting the overcurrent protection signal after receiving the overcurrent protection signal;
the judging unit is used for judging whether the overcurrent time is greater than the preset overcurrent time;
the first control unit is used for judging fault overcurrent output of the frequency converter when the overcurrent time is greater than the preset overcurrent time, and controlling the frequency converter to stop outputting;
and the second control unit is used for judging that the overcurrent protection device is interfered and controlling the frequency converter to continue working when the overcurrent time is not more than the preset overcurrent time.
In order to solve the above technical problem, the present invention provides an overcurrent protection apparatus, including:
a memory for storing a computer program;
and the processor is used for realizing the steps of the overcurrent protection method when executing the computer program.
In order to solve the above technical problem, the present invention provides a computer-readable storage medium, on which a computer program is stored, and the computer program, when executed by a processor, implements the steps of the over-current protection method as described above.
The application discloses an overcurrent protection method and a related assembly, in the scheme, because an overcurrent protection device is used for outputting an overcurrent protection signal when detecting that the input current of the overcurrent protection device is larger than an overcurrent protection value, specifically, when the overcurrent time is shorter and is not larger than the preset overcurrent time, the overcurrent protection signal can be judged to be output because the overcurrent protection device is interfered, at the moment, a frequency converter can normally work, otherwise, the overcurrent protection signal is output by the overcurrent protection device due to the fault of the frequency converter, the frequency converter needs to be controlled to stop outputting, and the frequency converter and a load are prevented from being burnt. In summary, in the present application, the magnitude of the overcurrent time when the overcurrent protection device outputs the overcurrent protection signal is compared with the preset overcurrent time to determine whether the overcurrent protection device outputs the overcurrent protection signal due to detecting the fault of the frequency converter or due to the interference, so as to perform corresponding control, and avoid the control of stopping the frequency converter due to the error caused by the interference.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed in the prior art and the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
Fig. 1 is a schematic flow chart of an overcurrent protection method according to the present invention;
fig. 2 is a schematic flow chart of a specific overcurrent protection method according to the present invention;
fig. 3 is a schematic structural diagram of an overcurrent protection system according to the present invention;
fig. 4 is a schematic structural diagram of an overcurrent protection apparatus provided in the present invention.
Detailed Description
The core of the invention is to provide an overcurrent protection method and related components, wherein the overcurrent protection device is judged whether the overcurrent protection device outputs the overcurrent protection signal due to the detection of the fault overcurrent output of the frequency converter or the self interference by comparing the magnitude between the overcurrent time of the overcurrent protection signal output by the overcurrent protection device and the preset overcurrent time, so that the corresponding control is carried out, and the control of stopping the frequency converter due to the error caused by the interference is avoided.
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, 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 some, but not all, embodiments of the present invention. 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.
Referring to fig. 1, fig. 1 is a schematic flow chart of an overcurrent protection method provided by the present invention, in which an input end of an overcurrent protection device is connected to an output end of a frequency converter, and is configured to output an overcurrent protection signal when detecting that its own input current is greater than an overcurrent protection value, and output an overcurrent stop signal when detecting that its own input current is not greater than the overcurrent protection value, the method includes:
s101: determining the overcurrent time of the overcurrent protection device for outputting the overcurrent protection signal based on the overcurrent protection signal and the overcurrent stop signal;
in this embodiment, the applicant considers that, when the overcurrent protection device in the prior art detects whether the frequency converter fails and outputs overcurrent, in order to ensure the sensitivity of the overcurrent protection device, the frequency converter can be timely controlled to stop working when the frequency converter fails and outputs overcurrent, and the frequency converter and the load are prevented from being burned out.
In order to solve the above technical problems, in the prior art, a circuit is usually added additionally to improve the anti-interference performance of the over-current protection device, but the additional addition of the circuit causes the increase of the cost, and the over-current protection device has certain requirements on the size of the over-current protection circuit, and is inconvenient to install; another way is to add software filtering to filter out short-time interference glitches, but this way can only filter out the interference glitches generated by the doublet and needs higher sampling frequency to implement, which also causes the increase of cost.
The overcurrent protection device outputs an overcurrent protection signal when detecting that the input current of the overcurrent protection device is larger than an overcurrent protection value, and outputs an overcurrent stop signal when detecting that the input current of the overcurrent protection device is not larger than the overcurrent protection value, wherein the input current of the overcurrent protection device can be the output current of the frequency converter, or can be the output current of the frequency converter and an interference signal.
It should be noted that, after the overcurrent protection device outputs the overcurrent protection signal, if it is not detected that the input current of the overcurrent protection device is not greater than the overcurrent protection value, the overcurrent protection signal is continuously output, and when it is detected that the input current of the overcurrent protection device is not greater than the overcurrent protection value, the overcurrent stop signal is output, and when it is not detected that the input current of the overcurrent protection device is greater than the overcurrent protection value, the overcurrent stop signal is continuously output, and based on this, the overcurrent time can be determined.
In addition, the over-current protection device outputs an over-current protection signal which can be but is not limited to TZ or brake interrupt of the processor, an over-current stop signal which can be but is not limited to external IO interrupt of the processor, and an over-current protection signal which can be but is not limited to falling edge trigger, and accordingly, the over-current stop signal is rising edge trigger.
S102: judging whether the overcurrent time is greater than the preset overcurrent time or not;
the applicant considers that when the frequency converter fails and outputs overcurrent, if the frequency converter is not controlled to stop outputting or solve the problem of the fault and overcurrent faults, the frequency converter can continuously output the fault and overcurrent, so that the overcurrent protection device continuously outputs overcurrent protection signals, when interference exists, the interference is sporadic signals and can not continuously occur in a short time, therefore, the occurrence time of the interference is less than the fault and overcurrent time, on the basis, whether the overcurrent time is greater than the preset overcurrent time is judged, and the reason why the overcurrent protection circuit outputs the overcurrent protection signals can be determined.
S103: if the overcurrent time is greater than the preset overcurrent time, judging the fault overcurrent output of the frequency converter, and controlling the frequency converter to stop outputting;
if the overcurrent time is greater than the preset overcurrent time, the fault overcurrent output of the frequency converter can be judged, and the frequency converter is controlled to stop outputting at the moment so as to avoid the load from being burnt out.
S104: and if the overcurrent time is not more than the preset overcurrent time, judging that the overcurrent protection device is interfered, and controlling the frequency converter to continue working.
If the overcurrent time is not greater than the preset overcurrent time, it can be determined that the overcurrent protection device outputs an overcurrent protection signal because the overcurrent protection device is interfered, and at the moment, the frequency converter does not have fault and overcurrent output, and the frequency converter is controlled to continue to normally work in order to meet the requirements of users.
In summary, in the present application, the magnitude of the overcurrent time when the overcurrent protection device outputs the overcurrent protection signal is compared with the preset overcurrent time to determine whether the overcurrent protection device outputs the overcurrent protection signal due to detecting the fault of the frequency converter or due to the interference, so as to perform corresponding control, and avoid the control of stopping the frequency converter due to the error caused by the interference.
On the basis of the above-described embodiment:
referring to fig. 2, fig. 2 is a specific flowchart of an overcurrent protection method according to the present invention.
As a preferred embodiment, the determining the overcurrent time when the overcurrent protection device outputs the overcurrent protection signal based on the overcurrent protection signal and the overcurrent stop signal includes:
s201: initializing the accumulated clock count value to be 0;
s202: when an overcurrent protection signal is received, recording a first current count value of a system clock, marking the position of an overcurrent mark as 1, and marking the position of an overcurrent cycle as 1;
s203: when an overcurrent stop signal is received, recording a second current count value of a system clock, marking the position of an overcurrent mark as 0, and updating the count value of the accumulated clock based on the difference value obtained by subtracting the first current count value from the second current count value;
s204: when receiving the over-current determination signal, determining whether the over-current period flag bit is 1, if so, entering step S205, and if not, entering step S209;
s205: judging whether the over-current flag bit is 1, if so, entering step S206, otherwise, entering step S207;
s206: updating the accumulated clock count value based on a difference value obtained by subtracting the first current count value from the third current count value of the system clock and the accumulated clock count value before updating;
s207: judging whether the updated accumulated clock count value is greater than a preset over-current accumulated count value or not, and if not, entering step S208;
s208: initializing an overcurrent cycle flag bit to be 0, controlling the frequency converter to restart, and returning to the step S202;
s209: judging whether the overcurrent protection signal is not received after the overcurrent stop signal is received for the last time and the preset time, if so, entering the step S210;
s210: and multiplying the updated accumulated clock count value by the period of the system clock to set the overcurrent time.
In this embodiment, in a shutdown state of the processor, the accumulated clock count value is 0, the overcurrent flag is 0, and the overcurrent cycle flag is 0, where the accumulated clock count value is used to record a clock count value between receiving the overcurrent protection signal and receiving the overcurrent stop signal, the overcurrent flag is used to indicate whether the overcurrent protection signal is currently received, and the overcurrent cycle flag is used to indicate whether the overcurrent protection signal is received in an overcurrent determination cycle.
Specifically, after receiving an overcurrent protection signal, setting an overcurrent flag position to 1, setting an overcurrent cycle flag position to 1, and recording a first current count value of a system clock when the overcurrent protection signal is received; after receiving the overcurrent stop signal, the overcurrent flag is set to 0, but this time is not a condition for setting the overcurrent cycle flag to 0.
Although the output of the PWM (Pulse width modulation) signal is stopped after receiving the overcurrent protection signal, the processor determines whether the overcurrent protection device outputs the overcurrent protection signal or not when the PWM triggers an interrupt program according to a set carrier frequency period, that is, when the processor receives the overcurrent determination signal, and determines the reason causing the overcurrent protection circuit to output the overcurrent protection signal when receiving the overcurrent protection signal.
After receiving the overcurrent judging signal, if the flag bit of the overcurrent period is 1, indicating that the processor receives the overcurrent protection signal in the current overcurrent judging period, and then judging whether the processor is in a state of receiving the overcurrent protection signal at present, namely whether the flag bit of the overcurrent is 1; if the over-current flag bit is 1, determining the count value of the current system clock, namely the third current count value, and the first current count value is the count value of the system clock at the time of TZ or brake interrupt falling edge triggering, if the overcurrent protection signal is received for the first time, the overcurrent stop signal is not received between the first current count value and the third current count value, the accumulated clock count value is still 0, the difference value obtained by subtracting the first current count value from the third current count value is assigned as the accumulated clock count value, so as to realize the update of the accumulated clock count value, however, if the overcurrent protection signal is not received for the first time, the accumulated clock count value is not 0, and the accumulated clock count value is updated by assigning a difference value obtained by subtracting the first current count value from the third current count value to the accumulated clock count value. However, if the over-current flag bit is not 1, the over-current stop signal is received at this time, and when the over-current stop signal is received, that is, when an external IO interrupt rising edge is triggered, the count value of the system clock is determined, that is, the second current count value is determined, if the over-current stop signal is received for the first time at this time, the accumulated clock count value is still 0, the difference value obtained by subtracting the first current count value from the second current count value is assigned as the accumulated clock count value, so that the update of the accumulated clock count value can be achieved.
After updating the accumulated clock count value, it can be obtained that the updated accumulated clock count value is the overcurrent time from the first time when the overcurrent protection signal is received to the current time, the judgment of whether the overcurrent time is greater than the preset overcurrent time can be realized by judging whether the updated accumulated clock count value is greater than the preset overcurrent accumulated count value, if the updated accumulated clock count value is not greater than the preset overcurrent accumulated count value, the flag bit of the overcurrent period is initialized to 0, and the frequency converter is controlled to restart again, if the overcurrent protection signal is output by the overcurrent protection device due to the fault and overcurrent of the frequency converter, the fault and overcurrent output still occurs after the frequency converter is restarted, after returning to step S202, the processor still receives the overcurrent protection signal sent by the overcurrent protection device, thereby recording the first current count value of the system clock when the overcurrent protection signal is received this time, and (4) resetting the overcurrent mark position 1 and the overcurrent period mark position 1 into a cycle. If the overcurrent protection device outputs an overcurrent protection signal due to interference, the interference is eliminated after the frequency converter is restarted, the processor cannot receive the overcurrent protection signal any more, the flag bit of the overcurrent period is 0, and if the overcurrent protection signal is not received again after the overcurrent stop signal is received for the last time, the current overcurrent is finished, the period of multiplying the updated accumulated clock count value by the system clock is set as the overcurrent time, and whether the frequency converter fails or not can be judged by judging whether the overcurrent time is greater than the preset overcurrent time or not.
It should be noted that, when determining whether the overcurrent protection signal is not received after the preset time has elapsed since the overcurrent stop signal was last received, the timing may be, but is not limited to, performed by a 100-microsecond clock in the system, so as to determine the time when no overcurrent occurs since the overcurrent stop signal was last received, and the preset time may be, but is not limited to, 3 ms.
In addition, the frequency converter is controlled to restart after overcurrent judgment every time, interference can be conveniently identified, and damage to a load or the frequency converter caused by continuous output of the frequency converter during fault overcurrent output can be avoided.
As a preferred embodiment, after determining whether the updated accumulated clock count value is greater than the preset overcurrent accumulated count value, the method further includes:
if yes, initializing an overcurrent cycle flag bit to be 0, and entering the step of judging the fault overcurrent output of the frequency converter and controlling the frequency converter to stop outputting.
When the updated accumulated clock count value is judged to be greater than the preset overcurrent accumulated count value, the updated accumulated clock count value is the overcurrent time from the first time when the overcurrent protection signal is received to the current time, and if the updated accumulated clock count value is greater than the preset overcurrent accumulated count value, the overcurrent protection signal output by the overcurrent protection device due to the fault and overcurrent output of the frequency converter can be judged, and the frequency converter is controlled to stop outputting, so that the load is prevented from being burnt out due to overcurrent of the frequency converter.
As a preferred embodiment, after the step of multiplying the updated accumulated clock count value by the period of the system clock is set as the overcurrent time, the method further includes:
and entering a step of judging whether the overcurrent time is greater than the preset overcurrent time.
In this embodiment, after the overcurrent time is determined, whether the overcurrent protection device outputs the overcurrent protection signal due to the fault overcurrent output of the frequency converter or the overcurrent protection signal due to the interference is determined by judging whether the overcurrent time is greater than the preset overcurrent time.
As a preferred embodiment, after determining whether the overcurrent protection signal is not received after the preset time has elapsed since the overcurrent stop signal was last received, the method further includes:
if not, returning to the step of recording the first current count value of the system clock, marking the position 1 of the overcurrent flag, and marking the position 1 of the overcurrent cycle when the overcurrent protection signal is received.
In this embodiment, if the current overcurrent cycle flag is 0 and the overcurrent protection signal is received before the preset time has elapsed since the overcurrent stop signal was received last time, it indicates that the current overcurrent fault or interference has not been removed, and it is necessary to continuously determine the reason for the overcurrent protection device to output the overcurrent protection signal according to the time from the time when the overcurrent protection signal is received to the current time or the time when the overcurrent stop signal is received.
It should be noted that, no matter the result is that the frequency converter fails and outputs overcurrent or the overcurrent protection device is interfered, whether the overcurrent protection signal is received or not is detected again after the frequency converter works normally, so that the real-time detection and protection of the frequency converter are performed.
Referring to fig. 3, fig. 3 is a schematic structural diagram of an overcurrent protection system according to the present invention, in which an overcurrent protection device is configured to output an overcurrent protection signal when detecting that its own input current is greater than an overcurrent protection value, and to stop outputting the overcurrent protection signal when detecting that its own input current is not greater than the overcurrent protection value, and the system includes:
the determining unit 301 is configured to determine, after receiving the overcurrent protection signal, an overcurrent time at which the overcurrent protection device outputs the overcurrent protection signal;
a judging unit 302, configured to judge whether the overcurrent time is greater than a preset overcurrent time;
the first control unit 303 is configured to determine that the frequency converter has a fault and performs overcurrent output when the overcurrent time is greater than a preset overcurrent time, and control the frequency converter to stop outputting;
and the second control unit 304 is configured to determine that the overcurrent protection device is interfered when the overcurrent time is not greater than the preset overcurrent time, and control the frequency converter to continue to operate.
For the introduction of the over-current protection system provided by the present invention, please refer to the above method embodiments, which are not described herein again.
Referring to fig. 4, fig. 4 is a schematic structural diagram of an overcurrent protection apparatus provided in the present invention, the apparatus includes:
a memory 401 for storing a computer program;
the processor 401 is configured to implement the steps of the overcurrent protection method when executing the computer program.
For the introduction of the over-current protection device provided by the present invention, please refer to the above method embodiments, which are not described herein again.
The computer readable storage medium in the present invention stores thereon a computer program, which when executed by the processor 401, implements the steps of the over-current protection method as described above.
For the introduction of the computer-readable storage medium provided by the present invention, please refer to the above method embodiments, which are not repeated herein.
It is further noted that, in the present specification, relational terms such as first and second, and the like are 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 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 (8)
1. An overcurrent protection method is characterized in that an input end of an overcurrent protection device is connected with an output end of a frequency converter and used for outputting an overcurrent protection signal when detecting that own input current is larger than an overcurrent protection value and outputting an overcurrent stop signal when detecting that own input current is not larger than the overcurrent protection value, and the method comprises the following steps:
determining the overcurrent time of the overcurrent protection device for outputting the overcurrent protection signal based on the overcurrent protection signal and the overcurrent stop signal;
judging whether the overcurrent time is greater than preset overcurrent time or not;
if so, judging the fault overcurrent output of the frequency converter, and controlling the frequency converter to stop outputting;
if not, judging that the overcurrent protection device is interfered, and controlling the frequency converter to continue working.
2. The overcurrent protection method of claim 1, wherein determining an overcurrent time for the overcurrent protection device to output the overcurrent protection signal based on the overcurrent protection signal and the overcurrent stop signal comprises:
s201: initializing the accumulated clock count value to be 0;
s202: when the overcurrent protection signal is received, recording a first current count value of a system clock, marking the position of an overcurrent mark as 1, and marking the position of an overcurrent cycle as 1;
s203: when the overcurrent stop signal is received, recording a second current count value of the system clock, positioning the overcurrent flag at 0, and updating the accumulated clock count value based on a difference value obtained by subtracting the first current count value from the second current count value;
s204: when receiving the over-current determination signal, determining whether the over-current period flag bit is 1, if so, entering step S205, and if not, entering step S209;
s205: judging whether the over-current flag bit is 1, if so, entering step S206, and if not, entering step S207;
s206: updating the accumulated clock count value based on a difference value obtained by subtracting the first current count value from a third current count value of the system clock and the accumulated clock count value before updating;
s207: judging whether the updated accumulated clock count value is larger than a preset over-current accumulated count value or not, and if not, entering the step S208;
s208: initializing the flag bit of the overcurrent cycle to be 0, controlling the frequency converter to restart, and returning to the step S202;
s209: judging whether the overcurrent protection signal is not received after a preset time since the overcurrent stop signal is received last time, if so, entering the step S210;
s210: and multiplying the updated accumulated clock count value by the period of the system clock to set the updated accumulated clock count value as the overcurrent time.
3. The overcurrent protection method according to claim 2, wherein after determining whether the updated accumulated clock count value is greater than a preset overcurrent accumulated count value, the method further comprises:
if yes, initializing the overcurrent cycle flag bit to be 0, judging the fault overcurrent output of the frequency converter, and controlling the frequency converter to stop outputting.
4. The overcurrent protection method according to claim 2, wherein, after the updated accumulated clock count value multiplied by the period of the system clock is set as the overcurrent time, further comprising:
and entering a step of judging whether the overcurrent time is greater than preset overcurrent time.
5. The overcurrent protection method according to claim 2, wherein after determining whether the overcurrent protection signal is not received after a preset time has elapsed since the overcurrent stop signal was last received, the method further comprises:
if not, returning to the step of recording the first current count value of the system clock, marking the position 1 of the overcurrent flag, and marking the position 1 of the overcurrent cycle when the overcurrent protection signal is received.
6. An overcurrent protection system, wherein the overcurrent protection device is configured to output an overcurrent protection signal when detecting that its own input current is greater than an overcurrent protection value, and to stop outputting the overcurrent protection signal when detecting that its own input current is not greater than the overcurrent protection value, the system comprising:
the determining unit is used for determining the overcurrent time of the overcurrent protection device for outputting the overcurrent protection signal after receiving the overcurrent protection signal;
the judging unit is used for judging whether the overcurrent time is greater than the preset overcurrent time;
the first control unit is used for judging fault overcurrent output of the frequency converter when the overcurrent time is greater than the preset overcurrent time, and controlling the frequency converter to stop outputting;
and the second control unit is used for judging that the overcurrent protection device is interfered and controlling the frequency converter to continue working when the overcurrent time is not more than the preset overcurrent time.
7. An overcurrent protection device, comprising:
a memory for storing a computer program;
a processor for implementing the steps of the overcurrent protection method as claimed in any one of claims 1 to 5 when executing the computer program.
8. A computer-readable storage medium, characterized in that a computer program is stored on the computer-readable storage medium, which computer program, when being executed by a processor, carries out the steps of the overcurrent protection method as set forth in any one of claims 1 to 5.
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Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110075307A1 (en) * | 2009-09-30 | 2011-03-31 | Fujitsu Ten Limited | Overcurrent protection circuit and in-vehicle display device |
| CN103490396A (en) * | 2013-09-25 | 2014-01-01 | 无锡中星微电子有限公司 | Current limiting circuit |
| CN104167716A (en) * | 2014-08-07 | 2014-11-26 | 珠海格力电器股份有限公司 | Protection control method and system of power factor correction circuit |
| WO2016037511A1 (en) * | 2014-09-10 | 2016-03-17 | 广州金升阳科技有限公司 | Power supply protection and control method |
| CN106054016A (en) * | 2016-08-17 | 2016-10-26 | 科博达技术有限公司 | Method for judging short circuit fault of inverter |
| CN106160440A (en) * | 2016-07-25 | 2016-11-23 | 阳光电源股份有限公司 | A kind of straight-flow system and control unit thereof and detection method |
| CN106230244A (en) * | 2016-08-18 | 2016-12-14 | 株洲中车时代电气股份有限公司 | A kind of converter over-current protection method, device and converter |
| CN106410759A (en) * | 2015-07-29 | 2017-02-15 | 青岛海尔空调电子有限公司 | Method and device for communication overcurrent protection of AC wire controller |
| CN107508252A (en) * | 2017-09-20 | 2017-12-22 | 深圳市华星光电技术有限公司 | A kind of current foldback circuit and display panel |
| CN107959277A (en) * | 2017-12-05 | 2018-04-24 | 上海空间电源研究所 | Satellite load input terminal Over Current Protection System |
| CN108736451A (en) * | 2017-04-24 | 2018-11-02 | 廊坊优尼珀焊接设备有限公司 | Overcurrent protection method and device for large power inverter power source |
| CN109066579A (en) * | 2018-09-20 | 2018-12-21 | 重庆惠科金渝光电科技有限公司 | A kind of over-voltage protection method and device |
| CN111063290A (en) * | 2019-12-25 | 2020-04-24 | Tcl华星光电技术有限公司 | Driving circuit, driving method and display panel |
| US20200153230A1 (en) * | 2018-11-14 | 2020-05-14 | Hewlett Packard Enterprise Development Lp | Systems and methods for input overcurrent protection |
| CN111181127A (en) * | 2020-02-13 | 2020-05-19 | 海信（山东）空调有限公司 | Circuit control device and method |
| CN112670957A (en) * | 2020-12-29 | 2021-04-16 | 联合汽车电子有限公司 | Vehicle-mounted DC/DC overcurrent diagnosis method and device and computer readable storage medium |
| CN113280468A (en) * | 2021-06-15 | 2021-08-20 | 佛山市顺德区美的电子科技有限公司 | Operation control method of air conditioner, air conditioner and computer readable storage medium |
| CN113572126A (en) * | 2021-09-23 | 2021-10-29 | 苏州浪潮智能科技有限公司 | Overcurrent protection method and device and power supply circuit |
-
2021
- 2021-12-09 CN CN202111501616.3A patent/CN114167970A/en active Pending
Patent Citations (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110075307A1 (en) * | 2009-09-30 | 2011-03-31 | Fujitsu Ten Limited | Overcurrent protection circuit and in-vehicle display device |
| CN103490396A (en) * | 2013-09-25 | 2014-01-01 | 无锡中星微电子有限公司 | Current limiting circuit |
| CN104167716A (en) * | 2014-08-07 | 2014-11-26 | 珠海格力电器股份有限公司 | Protection control method and system of power factor correction circuit |
| WO2016037511A1 (en) * | 2014-09-10 | 2016-03-17 | 广州金升阳科技有限公司 | Power supply protection and control method |
| CN106410759A (en) * | 2015-07-29 | 2017-02-15 | 青岛海尔空调电子有限公司 | Method and device for communication overcurrent protection of AC wire controller |
| CN106160440A (en) * | 2016-07-25 | 2016-11-23 | 阳光电源股份有限公司 | A kind of straight-flow system and control unit thereof and detection method |
| CN106054016A (en) * | 2016-08-17 | 2016-10-26 | 科博达技术有限公司 | Method for judging short circuit fault of inverter |
| CN106230244A (en) * | 2016-08-18 | 2016-12-14 | 株洲中车时代电气股份有限公司 | A kind of converter over-current protection method, device and converter |
| CN108736451A (en) * | 2017-04-24 | 2018-11-02 | 廊坊优尼珀焊接设备有限公司 | Overcurrent protection method and device for large power inverter power source |
| CN107508252A (en) * | 2017-09-20 | 2017-12-22 | 深圳市华星光电技术有限公司 | A kind of current foldback circuit and display panel |
| CN107959277A (en) * | 2017-12-05 | 2018-04-24 | 上海空间电源研究所 | Satellite load input terminal Over Current Protection System |
| CN109066579A (en) * | 2018-09-20 | 2018-12-21 | 重庆惠科金渝光电科技有限公司 | A kind of over-voltage protection method and device |
| US20200153230A1 (en) * | 2018-11-14 | 2020-05-14 | Hewlett Packard Enterprise Development Lp | Systems and methods for input overcurrent protection |
| CN111063290A (en) * | 2019-12-25 | 2020-04-24 | Tcl华星光电技术有限公司 | Driving circuit, driving method and display panel |
| CN111181127A (en) * | 2020-02-13 | 2020-05-19 | 海信（山东）空调有限公司 | Circuit control device and method |
| CN112670957A (en) * | 2020-12-29 | 2021-04-16 | 联合汽车电子有限公司 | Vehicle-mounted DC/DC overcurrent diagnosis method and device and computer readable storage medium |
| CN113280468A (en) * | 2021-06-15 | 2021-08-20 | 佛山市顺德区美的电子科技有限公司 | Operation control method of air conditioner, air conditioner and computer readable storage medium |
| CN113572126A (en) * | 2021-09-23 | 2021-10-29 | 苏州浪潮智能科技有限公司 | Overcurrent protection method and device and power supply circuit |
Non-Patent Citations (1)
| Title |
|---|
| 方佩敏;: "[负载开关设计(三)] 有电流限制的负载开关设计", 电子世界, no. 05, 1 May 2008 (2008-05-01), pages 11 - 13 * |
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