CN107918058B - Filter inductor detection method and device - Google Patents
Filter inductor detection method and device Download PDFInfo
- Publication number
- CN107918058B CN107918058B CN201711238379.XA CN201711238379A CN107918058B CN 107918058 B CN107918058 B CN 107918058B CN 201711238379 A CN201711238379 A CN 201711238379A CN 107918058 B CN107918058 B CN 107918058B
- Authority
- CN
- China
- Prior art keywords
- filter inductor
- current
- filter
- abnormal
- inductance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/26—Measuring inductance or capacitance; Measuring quality factor, e.g. by using the resonance method; Measuring loss factor; Measuring dielectric constants ; Measuring impedance or related variables
- G01R27/2611—Measuring inductance
Abstract
The invention provides a method for detecting a filter inductor, which comprises the following steps: before grid connection, applying a pulse signal with time t to an inverter circuit switch; sampling the current of the filter inductor at high frequency in real time; and judging whether the filter inductor is abnormal or not based on the acquired current of the filter inductor. The invention can effectively detect whether the filter inductor is invalid or not without adding extra devices. The invention also discloses a detection device of the filter inductor.
Description
Technical Field
The invention relates to the technical field of fault detection, in particular to a method and a device for detecting a filter inductor.
Background
When the direct current is converted into the alternating current, the alternating current filter inductor output by the inverter plays a role in smoothing the alternating current output current, so that the filter inductor plays an important role in the process that the inverter converts the direct current into the alternating current. The filter inductor is a self-made part, and due to the manufacturing process difference, after carrying, installing, vibrating or long-term aging operation, the risk of failure exists, so that the filter inductor needs to be detected to judge whether the filter inductor fails or not.
At present, a temperature sensor is usually added in the filter inductor to determine whether the filter inductor is out of order. And when the temperature detected by the temperature sensor is higher than the normal highest working temperature of the filter inductor, judging that the filter inductor is invalid. Therefore, in the existing mode for detecting the filter inductor, on one hand, the cost is increased due to the addition of the temperature sensor, the process difficulty of filter inductor production and manufacturing is increased, the consistency is difficult to control, the circuit of the temperature sensor is also long, the wiring is difficult, and the risk that other components and parts are damaged due to abnormal temperature is also caused. On the other hand, if the filter inductor of the inverter fails before the complete machine operates, the conventional detection method cannot judge whether the filter inductor fails before the complete machine of the inverter operates.
Therefore, how to effectively judge whether the filter inductor is damaged or failed is an urgent problem to be solved.
Disclosure of Invention
In view of this, the present invention provides a method for detecting a filter inductor, which can effectively detect whether the filter inductor is out of order without adding an additional device.
The invention provides a method for detecting a filter inductor, which comprises the following steps:
before grid connection, applying a pulse signal with time t to an inverter circuit switch;
sampling the current of the filter inductor at high frequency in real time;
and judging whether the filter inductor is abnormal or not based on the acquired current of the filter inductor.
Preferably, the method further comprises:
and generating fault prompt information when the filter inductor is judged to be abnormal.
Preferably, the judging whether the filter inductor is abnormal or not based on the collected current of the filter inductor includes:
judging whether the difference value of the maximum current and the minimum current of the filter inductor meets a preset condition or not;
when the difference value between the maximum current and the minimum current of the filter inductor meets a preset condition, judging whether the difference value between the maximum current and the minimum current of the filter inductor is smaller than a first preset threshold value, if so, enabling the filter inductor to be in a normal state, and if not, enabling the filter inductor to be in a normal state:
and judging whether the difference value of the maximum current and the minimum current of the filter inductor is greater than a second preset threshold value, if so, judging that the filter inductor is abnormal, wherein the second preset threshold value is greater than the first preset threshold value.
Preferably, when the difference between the maximum current and the minimum current of the filter inductor does not satisfy the preset condition, the method further includes:
calculating the reactance inductance quantity of the filter inductor;
and judging whether the filter inductor is abnormal or not based on the reactance inductance of the filter inductor.
Preferably, the determining whether the filter inductance is abnormal based on the reactance inductance of the filter inductance includes:
and judging whether the reactance inductance of the filter inductor is lower than a reactance inductance preset value or not, if so, judging that the filter inductor is abnormal.
A filter inductance detection device, comprising:
the controller is used for applying a pulse signal with time t to the inverter circuit switch before grid connection;
the current detection circuit is used for sampling the current of the filter inductor at high frequency in real time;
and the processor is used for judging whether the filter inductor is abnormal or not based on the acquired current of the filter inductor.
Preferably, the apparatus further comprises:
and the alarm is used for generating fault prompt information when the filter inductor is judged to be abnormal.
Preferably, the processor comprises:
the first judgment module is used for judging whether the difference value of the maximum current and the minimum current of the filter inductor meets a preset condition or not;
the second judging module is configured to, when the difference between the acquired maximum current and the acquired minimum current of the filter inductor meets a preset condition, judge whether the difference between the acquired maximum current and the acquired minimum current of the filter inductor is smaller than a first preset threshold, if yes, the filter inductor is in a normal state, and if not, the second judging module:
and judging whether the difference value of the maximum current and the minimum current of the filter inductor is greater than a second preset threshold value, if so, judging that the filter inductor is abnormal, wherein the second preset threshold value is greater than the first preset threshold value.
Preferably, the processor further comprises:
the calculation module is used for calculating the reactance inductance of the filter inductor when the difference value between the maximum current and the minimum current of the filter inductor does not meet the preset condition;
and the third judgment module is used for judging whether the filter inductor is abnormal or not based on the reactance inductance of the filter inductor.
Preferably, the third determining module is specifically configured to:
and judging whether the reactance inductance of the filter inductor is lower than a reactance inductance preset value or not, if so, judging that the filter inductor is abnormal.
According to the technical scheme, when fault detection needs to be carried out on the filter inductor, firstly, a pulse signal with the time of t is applied to an inverter circuit switch before grid connection, then high-frequency sampling is carried out on the current of the filter inductor in real time, so that reactance current can be collected more really, and whether the filter inductor is abnormal or not is judged according to the collected current of the filter inductor. The filter inductor can be effectively detected whether to fail or not without adding extra devices.
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 some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a flowchart of a method of detecting a filter inductor according to embodiment 1 of the present invention;
fig. 2 is a flowchart of a method of detecting a filter inductor according to embodiment 2 of the present invention;
fig. 3 is a flowchart of a method according to embodiment 3 of a method for detecting a filter inductor disclosed in the present invention;
fig. 4 is a schematic structural diagram of a detection apparatus for a filter inductor according to embodiment 1 of the present disclosure;
fig. 5 is a schematic structural diagram of a detection apparatus for a filter inductor according to embodiment 2 of the present invention;
fig. 6 is a schematic structural diagram of an embodiment 3 of a detection apparatus for a filter inductor according to the present invention;
FIG. 7 is a schematic diagram of a main circuit of a three-phase inverter circuit according to the present disclosure;
fig. 8 is a schematic diagram of an example of a detection apparatus for a filter inductor according to 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.
As shown in fig. 1, which is a flowchart of embodiment 1 of a method for detecting a filter inductance disclosed in the present invention, the method may include the following steps:
s101, applying a pulse signal with time t to an inverter circuit switch before grid connection;
when the filter inductor needs to be detected, a certain direct current voltage is applied to the inverter circuit before the inverter circuit is connected to the grid, namely, between the suction of the alternating current relay, pulse control is carried out on a fixed switch of the inverter circuit, and a pulse signal with the application time of t is applied.
S102, sampling the current of the filter inductor at high frequency in real time;
then, the current flowing through the filter inductor is sampled at high frequency in real time in a switching period, that is, the current of the filter inductor is sampled for a plurality of times in one switching period. Through high frequency sampling, the current that gathers can carry out better analysis. It should be noted that the collected current of the filter inductor includes a maximum value and a minimum value of the collected current.
S103, judging whether the filter inductor is abnormal or not based on the collected current of the filter inductor.
And then, judging the filter inductor according to the acquired current of the filter inductor, thereby detecting whether the filter inductor is abnormal or not.
In summary, in the above embodiment, when the fault detection of the filter inductor is required, firstly, a pulse signal with time t is applied to the inverter circuit switch before grid connection, then, high-frequency sampling is performed on the current of the filter inductor in real time, and whether the filter inductor is abnormal or not is determined according to the collected current of the filter inductor. The filter inductor can be effectively detected whether to fail or not without adding extra devices.
As shown in fig. 2, which is a flowchart of embodiment 2 of a method for detecting a filter inductance disclosed in the present invention, the method may include the following steps:
s201, applying a pulse signal with time t to an inverter circuit switch before grid connection;
when the filter inductor needs to be detected, a certain direct current voltage is applied to the inverter circuit before the inverter circuit is connected to the grid, namely, between the suction of the alternating current relay, pulse control is carried out on a fixed switch of the inverter circuit, and a pulse signal with the application time of t is applied.
S202, sampling the current of the filter inductor at high frequency in real time;
then, the current flowing through the filter inductor is sampled at high frequency in real time in a switching period, that is, the current of the filter inductor is sampled for a plurality of times in one switching period. Through high frequency sampling, the current that gathers can carry out better analysis. It should be noted that the collected current of the filter inductor includes a maximum value and a minimum value of the collected current.
S203, judging whether the difference value of the maximum current and the minimum current of the collected wave inductance meets a preset condition, if so, entering S204:
after the current of the filter inductor is collected in the switching period, the difference value between the maximum current ILmax and the minimum current ILmin of the collected filter inductor is judged, whether the difference value between the maximum current and the minimum current meets a preset condition or not is judged, and whether the difference value between the maximum current and the minimum current exceeds a certain value range or not is judged.
S204, judging whether the difference value of the maximum current and the minimum current of the collected filter inductor is smaller than a first preset threshold value, if so, entering S205, otherwise, entering S206:
when the difference value between the maximum current and the minimum current of the wave inductor meets a preset condition, whether the difference value between the maximum current ILmax and the minimum current ILmin of the filter inductor is smaller than a first preset threshold value Irate1 is further judged. The first preset threshold value Irate1 can be flexibly set according to the actual requirement of detection.
S205, enabling the filter inductor to be in a normal state;
when the difference value between the maximum current ILmax and the minimum current ILmin of the filter inductor is smaller than a first preset threshold value Irate1, the filter inductor is determined to be in a normal state.
S206, judging whether the difference value of the maximum current and the minimum current of the filter inductor is larger than a second preset threshold value, wherein the second preset threshold value is larger than the first preset threshold value, if so, entering S207:
when the difference value between the maximum current and the minimum current of the filter inductor is greater than or equal to a first preset threshold, further determining whether the difference value between the maximum current ILmax and the minimum current ILmin of the filter inductor is greater than a second preset threshold value Irate2, where the second preset threshold value Irate2 may be flexibly set according to the actual detection requirement. In addition, it should be noted that the second preset threshold value Irate2 is much larger than the first preset threshold value Irate1, for example, the second preset threshold value Irate2 is larger than twice the first preset threshold value Irate 1.
S207, enabling the filter inductor to be abnormal;
when the difference value between the maximum current ILmax and the minimum current ILmin of the filter inductor is greater than a second preset threshold value Irate2, the filter inductor is determined to be in an abnormal state.
And S208, generating fault prompt information.
When the filter inductor is judged to be in an abnormal state, fault prompt information can be further generated, so that detection personnel can judge that the filter inductor is abnormal more directly.
In summary, in this embodiment, on the basis of the above embodiment, whether the filter inductor is abnormal is further determined according to the difference between the maximum current and the minimum current of the filter inductor, when the difference between the maximum current and the minimum current of the filter inductor is smaller than a first preset threshold, the filter inductor is in a normal state according to the determination result, when the difference between the maximum current and the minimum current of the filter inductor is greater than a second preset threshold, the filter inductor is abnormal according to the determination result, and when the filter inductor is abnormal, a fault prompt message can be further generated, so that a detector can visually determine that the filter inductor is abnormal.
As shown in fig. 3, which is a flowchart of embodiment 3 of the method for detecting a filter inductance disclosed in the present invention, the method may include the following steps:
s301, applying a pulse signal with time t to an inverter circuit switch before grid connection;
when the filter inductor needs to be detected, a certain direct current voltage is applied to the inverter circuit before the inverter circuit is connected to the grid, namely, between the suction of the alternating current relay, pulse control is carried out on a fixed switch of the inverter circuit, and a pulse signal with the application time of t is applied.
S302, sampling the current of the filter inductor at high frequency in real time;
then, the current flowing through the filter inductor is subjected to high frequency in real time in a switching period, that is, the current of the filter inductor is sampled for a plurality of times in one switching period. By means of the high frequency, a better analysis of the collected current can be performed. It should be noted that the collected current of the filter inductor includes a maximum value and a minimum value of the collected current.
S303, judging whether the difference value of the maximum current and the minimum current of the acquired wave inductor meets a preset condition, if not, entering S304:
after the current of the filter inductor is collected in the switching period, the difference value between the maximum current ILmax and the minimum current ILmin of the collected filter inductor is judged, whether the difference value between the maximum current and the minimum current meets a preset condition or not is judged, and whether the difference value between the maximum current and the minimum current exceeds a certain value range or not is judged.
S304, calculating the reactance inductance of the filter inductor;
when the difference value between the maximum current and the minimum current of the filter inductor does not meet the preset condition, namely the difference value between the maximum current and the minimum current of the wave inductor is small, the fault of the filter inductor cannot be judged by the current of the filter inductor. In this case, the reactance of the filter inductance can be calculated. In calculating the reactance inductance of the filter inductor, taking the three-phase inverter circuit shown in fig. 7 as an example, the reactance of the filter inductor L1 is calculated in such a manner that Ldi/dt is UL, where UL is Ud-Uc2, and the voltage of Uc2 is Ud, where d is a sine wave duty ratio set for an IGBT module in the inverter circuit, Uc2 is the voltage of the filter capacitor c2, and Ud is a bus voltage.
S305, judging whether the filter inductance is abnormal or not based on the reactance inductance of the filter inductance.
And then judging whether the filter inductor is abnormal or not according to the calculated reactance inductance of the filter inductor.
Specifically, when judging whether the filter inductor is abnormal according to the calculated reactance inductance of the filter inductor, when the reactance inductance of the filter inductor is lower than a preset reactance inductance value, the judgment result is that the filter inductor is abnormal. When the filter inductor is abnormal, fault prompt information can be generated, so that a detector can judge that the filter inductor is abnormal more directly.
In summary, in this embodiment, on the basis of the above embodiment, when the filter inductance is not enough to be determined by the difference between the maximum current and the minimum current of the filter inductance, whether the filter inductance is abnormal or not can be determined based on the reactance inductance of the filter inductance by calculating the reactance inductance of the filter inductance, and when the reactance inductance of the filter inductance is lower than the reactance inductance preset value, it indicates that the filter inductance is abnormal.
As shown in fig. 4, which is a schematic structural diagram of an embodiment 1 of a filter inductance detection apparatus disclosed in the present invention, the apparatus may include:
the controller 401 is used for applying a pulse signal with time t to the inverter circuit switch before grid connection;
when the filter inductor needs to be detected, a certain direct current voltage is applied to the inverter circuit before the inverter circuit is connected to the grid, namely, between the suction of the alternating current relay, pulse control is carried out on a fixed switch of the inverter circuit, and a pulse signal with the application time of t is applied.
The current detection circuit 402 is used for sampling the current of the filter inductor at a high frequency in real time;
then, the current flowing through the filter inductor is sampled at high frequency in real time in a switching period, that is, the current of the filter inductor is sampled for a plurality of times in one switching period. Through high frequency sampling, the current that gathers can carry out better analysis. It should be noted that the collected current of the filter inductor includes a maximum value and a minimum value of the collected current.
And the processor 403 is configured to determine whether the filter inductor is abnormal based on the collected current of the filter inductor.
And then, judging the filter inductor according to the acquired current of the filter inductor, thereby detecting whether the filter inductor is abnormal or not.
In summary, in the above embodiment, when the fault detection of the filter inductor is required, firstly, a pulse signal with time t is applied to the inverter circuit switch before grid connection, then, high-frequency sampling is performed on the current of the filter inductor in real time, and whether the filter inductor is abnormal or not is determined according to the collected current of the filter inductor. The filter inductor can be effectively detected whether to fail or not without adding extra devices.
Specifically, in order to more clearly illustrate the above embodiments, a detailed description is given below with reference to a specific example.
Fig. 8 is a schematic diagram of an example of a filter inductor detection device according to the present invention. As shown in the figure, when the filter inductor L1 needs to be detected, a controller in the control circuit applies a certain dc voltage to the inverter circuit, and performs pulse control on a fixed switch of the inverter circuit, applying a pulse signal for time t.
Then, the current detection circuit in the current detection and protection circuit connected to the current detection point CT3 between the inverter circuit and the filter inductor L1 samples the current flowing through the filter inductor at high frequency in real time in a switching period, for example, the current sensor in the current detection circuit samples the current of the filter inductor multiple times in one switching period.
And then, judging the filter inductor according to the current of the filter inductor collected by the current detection circuit through a processor in a control circuit connected with the current detection and protection circuit, thereby detecting whether the filter inductor is abnormal or not.
As shown in fig. 5, which is a schematic structural diagram of an embodiment 2 of a filter inductance detection apparatus disclosed in the present invention, the apparatus may include:
the controller 501 is used for applying a pulse signal with time t to an inverter circuit switch before grid connection;
when the filter inductor needs to be detected, a certain direct current voltage is applied to the inverter circuit before the inverter circuit is connected to the grid, namely, between the suction of the alternating current relay, pulse control is carried out on a fixed switch of the inverter circuit, and a pulse signal with the application time of t is applied.
The current detection circuit 502 is used for sampling the current of the filter inductor at a high frequency in real time;
then, the current flowing through the filter inductor is sampled at high frequency in real time in a switching period, that is, the current of the filter inductor is sampled for a plurality of times in one switching period. Through high frequency sampling, the current that gathers can carry out better analysis. It should be noted that the collected current of the filter inductor includes a maximum value and a minimum value of the collected current.
A first judging module 503, configured to judge whether a difference between a maximum current and a minimum current of the acquired wave inductor satisfies a preset condition;
after the current of the filter inductor is collected in the switching period, the difference value between the maximum current ILmax and the minimum current ILmin of the collected filter inductor is judged, whether the difference value between the maximum current and the minimum current meets a preset condition or not is judged, and whether the difference value between the maximum current and the minimum current exceeds a certain value range or not is judged.
A second determining module 504, configured to determine, when a difference between the maximum current and the minimum current of the filter inductor meets a preset condition, whether the difference between the maximum current and the minimum current of the filter inductor is smaller than a first preset threshold, if so, the filter inductor is in a normal state, otherwise, whether the difference between the maximum current and the minimum current of the filter inductor is greater than a second preset threshold, where the second preset threshold is greater than the first preset threshold, and if so, the filter inductor is abnormal;
when the difference value between the maximum current and the minimum current of the wave inductor meets a preset condition, whether the difference value between the maximum current ILmax and the minimum current ILmin of the filter inductor is smaller than a first preset threshold value Irate1 is further judged. The first preset threshold value Irate1 can be flexibly set according to the actual requirement of detection.
When the difference value between the maximum current ILmax and the minimum current ILmin of the filter inductor is smaller than a first preset threshold value Irate1, the filter inductor is determined to be in a normal state.
When the difference value between the maximum current and the minimum current of the filter inductor is greater than or equal to a first preset threshold, further determining whether the difference value between the maximum current ILmax and the minimum current ILmin of the filter inductor is greater than a second preset threshold value Irate2, where the second preset threshold value Irate2 may be flexibly set according to the actual detection requirement. In addition, it should be noted that the second preset threshold value Irate2 is much larger than the first preset threshold value Irate1, for example, the second preset threshold value Irate2 is larger than twice the first preset threshold value Irate 1.
When the difference value between the maximum current ILmax and the minimum current ILmin of the filter inductor is greater than a second preset threshold value Irate2, the filter inductor is determined to be in an abnormal state.
And the alarm 505 is used for generating fault prompt information.
When the filter inductor is judged to be in an abnormal state, fault prompt information can be further generated, so that detection personnel can judge that the filter inductor is abnormal more directly.
In summary, in this embodiment, on the basis of the above embodiment, whether the filter inductor is abnormal is further determined according to the difference between the maximum current and the minimum current of the filter inductor, when the difference between the maximum current and the minimum current of the filter inductor is smaller than a first preset threshold, the filter inductor is in a normal state according to the determination result, when the difference between the maximum current and the minimum current of the filter inductor is greater than a second preset threshold, the filter inductor is abnormal according to the determination result, and when the filter inductor is abnormal, a fault prompt message can be further generated, so that a detector can visually determine that the filter inductor is abnormal.
As shown in fig. 6, which is a schematic structural diagram of an embodiment 3 of the detection apparatus for a filter inductor disclosed in the present invention, the apparatus may include:
the controller 601 is used for applying a pulse signal with time t to the inverter circuit switch before grid connection;
when the filter inductor needs to be detected, a certain direct current voltage is applied to the inverter circuit before the inverter circuit is connected to the grid, namely, between the suction of the alternating current relay, pulse control is carried out on a fixed switch of the inverter circuit, and a pulse signal with the application time of t is applied.
The current detection circuit 602 is configured to perform high-frequency sampling on the current of the filter inductor in real time;
then, the current flowing through the filter inductor is sampled at high frequency in real time in a switching period, that is, the current of the filter inductor is sampled for a plurality of times in one switching period. Through high frequency sampling, the current that gathers can carry out better analysis. It should be noted that the collected current of the filter inductor includes a maximum value and a minimum value of the collected current.
A first judging module 603, configured to judge whether a difference between a maximum current and a minimum current of the acquired wave inductor satisfies a preset condition;
after the current of the filter inductor is collected in the switching period, the difference value between the maximum current ILmax and the minimum current ILmin of the collected filter inductor is judged, whether the difference value between the maximum current and the minimum current meets a preset condition or not is judged, and whether the difference value between the maximum current and the minimum current exceeds a certain value range or not is judged.
A calculating module 604, configured to calculate a reactance of the filter inductor;
when the difference value between the maximum current and the minimum current of the filter inductor does not meet the preset condition, namely the difference value between the maximum current and the minimum current of the wave inductor is small, the fault of the filter inductor cannot be judged by the current of the filter inductor. In this case, the reactance of the filter inductance can be calculated. In calculating the reactance inductance of the filter inductor, taking the three-phase inverter circuit shown in fig. 7 as an example, the reactance of the filter inductor L1 is calculated in such a manner that Ldi/dt is UL, where UL is Ud-Uc2, and the voltage of Uc2 is Ud, where d is a sine wave duty ratio set for an IGBT module in the inverter circuit, Uc2 is the voltage of the filter capacitor c2, and Ud is a bus voltage.
A third determining module 605, configured to determine whether the filter inductor is abnormal based on the reactance inductance of the filter inductor.
And then judging whether the filter inductor is abnormal or not according to the calculated reactance inductance of the filter inductor.
Specifically, when judging whether the filter inductor is abnormal according to the calculated reactance inductance of the filter inductor, when the reactance inductance of the filter inductor is lower than a preset reactance inductance value, the judgment result is that the filter inductor is abnormal. When the filter inductor is abnormal, fault prompt information can be generated, so that a detector can judge that the filter inductor is abnormal more directly.
In summary, in this embodiment, on the basis of the above embodiment, when the filter inductance is not enough to be determined by the difference between the maximum current and the minimum current of the filter inductance, whether the filter inductance is abnormal or not can be determined based on the reactance inductance of the filter inductance by calculating the reactance inductance of the filter inductance, and when the reactance inductance of the filter inductance is lower than the reactance inductance preset value, it indicates that the filter inductance is abnormal.
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.
Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.
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 (8)
1. A method for detecting a filter inductance, the method comprising:
before grid connection, applying a pulse signal with time t to an inverter circuit switch;
sampling the current of the filter inductor at high frequency in real time;
judging whether the filter inductor is abnormal or not based on the collected current of the filter inductor, wherein the judging whether the filter inductor is abnormal or not based on the collected current of the filter inductor comprises:
judging whether the difference value of the maximum current and the minimum current of the filter inductor meets a preset condition or not;
when the difference value between the maximum current and the minimum current of the filter inductor meets a preset condition, judging whether the difference value between the maximum current and the minimum current of the filter inductor is smaller than a first preset threshold value, if so, enabling the filter inductor to be in a normal state, and if not, enabling the filter inductor to be in a normal state:
and judging whether the difference value of the maximum current and the minimum current of the filter inductor is greater than a second preset threshold value, if so, judging that the filter inductor is abnormal, wherein the second preset threshold value is greater than the first preset threshold value.
2. The method of claim 1, further comprising:
and generating fault prompt information when the filter inductor is judged to be abnormal.
3. The method of claim 1, wherein when the difference between the maximum current and the minimum current of the filter inductor does not satisfy a preset condition, the method further comprises:
calculating the reactance inductance quantity of the filter inductor;
and judging whether the filter inductor is abnormal or not based on the reactance inductance of the filter inductor.
4. The method of claim 3, wherein the determining whether the filter inductance is abnormal based on the reactance inductance of the filter inductance comprises:
and judging whether the reactance inductance of the filter inductor is lower than a reactance inductance preset value or not, if so, judging that the filter inductor is abnormal.
5. A device for detecting a filter inductance, comprising:
the controller is used for applying a pulse signal with time t to the inverter circuit switch before grid connection;
the current detection circuit is used for sampling the current of the filter inductor at high frequency in real time;
the processor is used for judging whether the filter inductor is abnormal or not based on the collected current of the filter inductor, and comprises a first judging module and a second judging module;
the first judgment module is used for judging whether the difference value of the maximum current and the minimum current of the filter inductor meets a preset condition or not;
the second judging module is configured to, when the difference between the acquired maximum current and the acquired minimum current of the filter inductor meets a preset condition, judge whether the difference between the acquired maximum current and the acquired minimum current of the filter inductor is smaller than a first preset threshold, if yes, the filter inductor is in a normal state, and if not, the second judging module:
and judging whether the difference value of the maximum current and the minimum current of the filter inductor is greater than a second preset threshold value, if so, judging that the filter inductor is abnormal, wherein the second preset threshold value is greater than the first preset threshold value.
6. The apparatus of claim 5, further comprising:
and the alarm is used for generating fault prompt information when the filter inductor is judged to be abnormal.
7. The apparatus of claim 5, wherein the processor further comprises:
the calculation module is used for calculating the reactance inductance of the filter inductor when the difference value between the maximum current and the minimum current of the filter inductor does not meet the preset condition;
and the third judgment module is used for judging whether the filter inductor is abnormal or not based on the reactance inductance of the filter inductor.
8. The apparatus according to claim 7, wherein the third determining module is specifically configured to:
and judging whether the reactance inductance of the filter inductor is lower than a reactance inductance preset value or not, if so, judging that the filter inductor is abnormal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711238379.XA CN107918058B (en) | 2017-11-30 | 2017-11-30 | Filter inductor detection method and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711238379.XA CN107918058B (en) | 2017-11-30 | 2017-11-30 | Filter inductor detection method and device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107918058A CN107918058A (en) | 2018-04-17 |
| CN107918058B true CN107918058B (en) | 2020-05-22 |
Family
ID=61897187
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711238379.XA Active CN107918058B (en) | 2017-11-30 | 2017-11-30 | Filter inductor detection method and device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107918058B (en) |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20130095819A (en) * | 2010-12-06 | 2013-08-28 | 미쓰비시덴키 가부시키가이샤 | Inductance measurement device and measurement method for synchronous electric motor |
| CN102714480B (en) * | 2011-03-30 | 2015-03-18 | 深圳市英威腾电气股份有限公司 | Inductance parameter identification method of synchronous motor and implementation system thereof |
| CN104730363B (en) * | 2013-12-20 | 2018-01-12 | 维谛技术有限公司 | A kind of filter detection method and apparatus |
| CN105785173B (en) * | 2016-03-11 | 2019-06-04 | 深圳茂硕电气有限公司 | A kind of intelligent detection device and its detection mode of inverter ac filter inductance |
-
2017
- 2017-11-30 CN CN201711238379.XA patent/CN107918058B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN107918058A (en) | 2018-04-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA2814326C (en) | Power converter resonance detection apparatus and method | |
| AU2010282204B2 (en) | Method for detecting arcs in photovoltaic systems and such a photovoltaic system | |
| CN104038074B (en) | Method and apparatus for ripple and pile defection | |
| JP6164848B2 (en) | Arc detector | |
| US9091742B2 (en) | Fault identification techniques for high resistance grounded systems | |
| CN105093082A (en) | DC fault arc detection method | |
| CN108761319B (en) | Relay failure detection method, device and system for photovoltaic grid-connected inverter | |
| CN109417285B (en) | Direct current electric loop protection device and arc detection method | |
| JP4515937B2 (en) | Voltage drop detection method and apparatus by waveform comparison | |
| CN109655757B (en) | UPS system detection method and system | |
| EP2857852A1 (en) | Systems and methods for detecting partial discharge in electrical components | |
| JP2010286306A (en) | Insulation resistance detector | |
| CN105850024B (en) | Power inverter | |
| CN205193210U (en) | Direct current trouble arc detection device | |
| CN105425055A (en) | Input open-phase detection apparatus and method, and multi-phase AC input electronic device | |
| CN109406890B (en) | Three-phase AC input open-phase detection method, system, equipment and storage medium | |
| CN111398750B (en) | Arc identification method and system for arc identification | |
| CN111103554A (en) | Power failure detection method, device, circuit system and computer storage medium | |
| CN107918058B (en) | Filter inductor detection method and device | |
| KR101277141B1 (en) | Electric watt-hour meter and method for monitoring power distribution system | |
| EP1646525B1 (en) | Monitoring an operation of a converter | |
| CN101938116B (en) | Relay protection method and device | |
| CN104950207A (en) | Short circuit detecting method and device for photovoltaic inverter | |
| EP3509177B1 (en) | Method for detecting earth-fault conditions in a power conversion apparatus | |
| CN104977479B (en) | Three-phase electricity condition detection apparatus, method and electric system |
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 |