CN108599094A - A kind of current protecting circuit and electric machine controller - Google Patents
A kind of current protecting circuit and electric machine controller Download PDFInfo
- Publication number
- CN108599094A CN108599094A CN201810247716.XA CN201810247716A CN108599094A CN 108599094 A CN108599094 A CN 108599094A CN 201810247716 A CN201810247716 A CN 201810247716A CN 108599094 A CN108599094 A CN 108599094A
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- current
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Classifications
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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
-
- 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
- H02H7/122—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 inverters, i.e. dc/ac converters
- H02H7/1227—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 inverters, i.e. dc/ac converters responsive to abnormalities in the output circuit, e.g. short circuit
Abstract
The invention discloses a kind of current protecting circuits; apply to three-phase inverter; including the current-sensing circuit in the U phases and W phases of three-phase inverter is arranged; the current signal of V phase output terminals is calculated using computing circuit; using analysis circuit when third current signal is more than the judgement signal of reference signal circuit input, triggering three-phase inverter carries out current protection operation.Technical scheme of the present invention reduces equipment cost, improves the accuracy of current detecting.
Description
Technical field
The present invention relates to electric motor protecting control field more particularly to a kind of current protecting circuit and electric machine controllers.
Background technology
With the development of pure electric automobile, the core component electric machine controller as pure electric automobile becomes research weight
Point.Existing electric machine controller carries out motor control using three-phase inverter, thus, three-phase inverter output end current is carried out
The technology of monitoring and current protection, is of great significance for the stability of pure electric automobile.
Existing current monitoring and current protection to three-phase inverter passes through sample motor respectively using current sensor
Electric current in controller on three-phase, to be effectively protected in real time to three-phase output.But it while detecting the electric current of three-phase and leads
Higher equipment cost is caused, and the electric current of three-phase can not mutually contrast reference, be unfavorable for the accuracy of current monitoring.
Invention content
For the above problem existing for electric machine controller field in the prior art, a kind of current protecting circuit and electricity are now provided
Machine controller.
Specific technical solution is as follows：
A kind of current protecting circuit is suitable for three-phase inverter, including：
The input terminal of first current-sensing circuit, first current-sensing circuit connects the U phases of the three-phase inverter
Output end, the first current signal for obtaining the U phase output terminals；
The input terminal of second current-sensing circuit, second current-sensing circuit connects the W phases of the three-phase inverter
Output end, the second current signal for obtaining the W phase output terminals；
The input terminal of computing circuit, the computing circuit is separately connected output end and the institute of first current-sensing circuit
The output end of the second current-sensing circuit is stated, institute is obtained for first current signal to be added with second current signal
State the third current signal of the V phase output terminals of three-phase inverter；
Analysis circuit connects the output end of the computing circuit, judges electric current for being more than in the third current signal
When signal, triggers the three-phase inverter and carry out current protection operation
The input terminal of reference signal circuit, the reference signal circuit connects a constant voltage source, the reference signal circuit
Output end connect the analysis circuit, for generating the judgement current signal.
Preferably, first current-sensing circuit and second current-sensing circuit are identical electric current induced electricity
Road,
Each current-sensing circuit includes respectively an inductor, the conducting wire of the U phase output terminals and the W phase output terminals
Conducting wire be each passed through the induction coil in the corresponding inductor.
Preferably, the current-sensing circuit further includes：
First capacitance, both ends are separately connected first node and second node；
First resistor, both ends are separately connected the first node and third node；
Second capacitance, both ends are separately connected the third node and fourth node；
Second resistance, both ends are separately connected the third node and the 5th node；
Third capacitance, both ends are separately connected the second node and the 6th node；
4th capacitance, both ends are separately connected the fourth node and the 6th node；
The signal output end of the inductor connects the first node, the ground terminal connection described second of the inductor
The power input of node, the inductor connects the 6th node；
6th node is also connected with the constant voltage source, and the third node connects the output of the current-sensing circuit
End, the 5th node ground connection；
The fourth node is separately connected the second node and the 5th node.
Preferably, the computing circuit includes：
Comparator, it is described to obtain for first current signal and second current signal to be summed up operation
Third current signal；
3rd resistor, both ends are separately connected the output end and the 7th node of first current-sensing circuit；
4th resistance, both ends are separately connected the output end and the 7th node of second current-sensing circuit；
5th resistance, both ends are separately connected the 7th node and the 8th node；
5th capacitance, both ends are separately connected the 7th node and the 8th node；
6th capacitance, both ends are separately connected the 9th node and protelum point；
The normal phase input end of the comparator connects the output end of a biasing circuit, and the negative-phase input of the comparator connects
The 7th node is connect, the positive voltage input terminal of the comparator connects the 9th node, and the negative voltage of the comparator is defeated
Enter end and connect the protelum point, the output end of the comparator connects the 8th node；
9th node connects the constant voltage source, the protelum point ground connection, and the 8th node connects the fortune
Calculate the output end of circuit.
Preferably, the biasing circuit includes：
Controlled rectifier connects the 11st node, anode the 13rd node of connection, control pole connection the 12nd described in cathode
Node；
7th capacitance, both ends are separately connected the 12nd node and the 13rd node；
6th resistance, both ends are separately connected the 12nd node and a constant voltage source.
The 13rd node ground connection, the 11st node connect the output end of the biasing circuit.
Preferably, the analysis circuit includes：
Signal receiving module is separately connected the output end of the output end and the reference signal circuit of the computing circuit,
For obtaining the third current signal and the judgement current signal；
Signal analysis module is separately connected the signal receiving module and the three-phase inverter, is used for the third
Current signal and the judgement current signal are compared, and when the third current signal is more than the judgement current signal
The level signal that saltus step is exported to the three-phase inverter, to control the three-phase inverter trigger current protection operation.
Preferably, a kind of electric machine controller, including a three-phase inverter, the three-phase inverter include any of the above-described described
Current protecting circuit.
Above-mentioned technical proposal has the following advantages that or advantageous effect：
Using real-time sampling biphase current, biphase current is added to obtain the electric current of third phase, according to third phase electricity
The instantaneous value of stream is compared judgement with threshold value, and current protection is carried out when realizing current signal exception.Said program, which reduces, to be set
Standby cost, improves the accuracy of current detecting.
Description of the drawings
With reference to appended attached drawing, more fully to describe the embodiment of the present invention.However, appended attached drawing be merely to illustrate and
It illustrates, and is not meant to limit the scope of the invention.
Fig. 1 is a kind of overall structure diagram of current protecting circuit embodiment of the present invention；
Fig. 2 is the electrical block diagram of current-sensing circuit in the embodiment of the present invention；
Fig. 3 is the electrical block diagram of computing circuit in the embodiment of the present invention；
Fig. 4 is the structural schematic diagram of analysis circuit in the embodiment of the present invention.
Specific implementation mode
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation describes, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, those of ordinary skill in the art obtained under the premise of not making creative work it is all its
His embodiment, shall fall within the protection scope of the present invention.
It should be noted that in the absence of conflict, the feature in embodiment and embodiment in the present invention can phase
Mutually combination.
The invention will be further described in the following with reference to the drawings and specific embodiments, but not as limiting to the invention.
In a kind of preferably implementation of the invention, according to Fig. 1 and Fig. 4, a kind of current protecting circuit is suitable for three contraries
Become device, including：
The U phases of first current-sensing circuit 11, the input terminal connection three-phase inverter of the first current-sensing circuit 11 export
End, the first current signal for obtaining U phase output terminals；
The W phases of second current-sensing circuit 12, the input terminal connection three-phase inverter of the second current-sensing circuit 12 export
End, the second current signal for obtaining W phase output terminals；
The input terminal of computing circuit 3, computing circuit 3 is separately connected the output end and the second electricity of the first current-sensing circuit 11
The output end for flowing sensor circuit 12, the V for obtaining three-phase inverter according to the first current signal and the second current signal operation
The third current signal of phase output terminal；
Analysis circuit 4 connects the output end of computing circuit 3, is used for when third current signal is more than current signal is judged,
It triggers three-phase inverter and carries out current protection operation；
The input terminal of reference signal circuit 42, reference signal circuit 42 connects a constant voltage source VDD, reference signal circuit 42
Output end linking parsing circuit 4, for generate judge current signal.
Specifically, in the present embodiment, three-phase is obtained by the first current-sensing circuit 11 and the second current-sensing circuit 12
The biphase current of inverter obtains the electric current of third phase by computing circuit 3, by analysis circuit 4 judge whether to need into
Row current protection.
In a kind of preferably implementation of the invention, according to Fig.2, the first current-sensing circuit 11 and the second electric current induced electricity
Road 12 is identical current-sensing circuit；
Each current-sensing circuit includes respectively the conducting wire of inductor M1, U a phase output terminal and the conducting wire difference of W phase output terminals
Induction coil in corresponding inductor M1.
Specifically, in the present embodiment, the first current-sensing circuit 11 and the second current-sensing circuit 12 use identical electricity
Line structure and sensing device so that the error between the current signal of the two-phase detected reduces.The current signal of two-phase passes through
Identical test environment obtains so that the current signal of two-phase need not carry out signal conversion and debugging, be directly inputted into logic
Operation is carried out in circuit obtains the current signal of third phase.Using the conducting wire and W phase output terminals of induction coil and U phase output terminals
Conducting wire is attached, and the input terminal for being equivalent to computing circuit 3 in above-mentioned technical proposal is separately connected the first current-sensing circuit 11
Output end and the second current-sensing circuit 12 output end, induction coil is considered as the input terminal of computing circuit 3.
In a kind of preferably implementation of the invention, according to Fig.2, current-sensing circuit further includes：
First capacitance C1, both ends are separately connected first node N1 and second node N2；
First resistor R1, both ends are separately connected first node N1 and third node N3；
Second capacitance C2, both ends are separately connected third node N3 and fourth node N4；
Second resistance R1, both ends are separately connected third node N3 and the 5th node N5；
Third capacitance C3, both ends are separately connected second node N2 and the 6th node N6；
4th capacitance C4, both ends are separately connected fourth node N4 and the 6th node N6；
The ground terminal of signal output end a1 connections the first node N1, inductor M1 of inductor M1 connect second node N2,
The 6th node N6 of power input a3 connections of inductor M1；
6th node N6 is also connected with constant voltage source VDD, the output end I1 of third node N3 connection current-sensing circuits, and the 5th
Node N5 ground connection；
Fourth node N4 is separately connected second node N2 and the 5th node N5.
Specifically, in the present embodiment, inductor M1 is current sensor device, and U phase output terminals are exchanged with W phase output terminals
Electricity can induce electromotive force, the signal that electromotive force passes through inductor M1 in the induction coil of inductor M1 when being exported by conducting wire
Output end a1 is measured, and is exported by the output end I1 of current-sensing circuit and is carried out operation into computing circuit 3.Constant voltage source
VDD uses 5V voltages.
In a kind of preferably implementation of the invention, according to Fig.3, computing circuit 3 includes：
Comparator, for the first current signal and the second current signal to be summed up operation to obtain third electric current letter
Number；
3rd resistor R3, both ends are separately connected the output end I11 and the 7th node N7 of the first current-sensing circuit 11；
4th resistance R4, both ends are separately connected the output end I12 and the 7th node N7 of the second current-sensing circuit 12；
5th resistance R5, both ends are separately connected the 7th node N7 and the 8th node N8；
5th capacitance C5, both ends are separately connected the 7th node N7 and the 8th node N8；
6th capacitance C6, both ends are separately connected the 9th node N9 and protelum point N10；
One biasing circuit of normal phase input end b1 connections of comparator M2, Section seven of the negative-phase input b2 connections of comparator M2
The negative voltage input terminal b4 connections the tenth of positive voltage input terminal b3 connections the 9th node N9, comparator M2 of point N7, comparator M2
The 8th node N8 of output end b5 connections of node N10, comparator M2；
9th node N9 connection constant voltage source VDD, protelum point N10 ground connection, the 8th node N8 connections computing circuit 3 it is defeated
Outlet I13.
Specifically, in the present embodiment, using comparator M2 as operational amplifier in computing circuit 3, in computing circuit 3
It is used as adder, the voltage of U, W two-phase is added, the knot being added according to Kirchhoff's law, U, W biphase current value
Fruit is the current value of V phases.
The constant voltage source of the positive voltage input terminal b3 connections 5V of comparator M2 is powered, the negative voltage input of comparator M2
B4 ground connection, the normal phase input end b1 of comparator M2 is held to connect the biasing circuit of constant input 2.5V, the negative input of comparator M2
B2 is held to access the first current signal and the second current signal, the signal of the output end b5 outputs of comparator M2 is believed for third electric current
Number.
In a kind of preferably implementation of the invention, according to Fig.3, biasing circuit includes：
Controlled rectifier D1, cathode connect the 11st node N11, anode the 13rd node N13 of connection, control pole connection the
12 node N12；
7th capacitance C7, both ends are separately connected the 12nd node N12 and the 13rd node N13；
6th resistance R6, both ends are separately connected the 12nd node N12 and a constant voltage source VDD.
13rd node N13 ground connection, the 11st node N11 connections connect the output end of biasing circuit.
Specifically, in the present embodiment, the bias voltage of 2.5V is provided using above-mentioned biasing circuit.
In a kind of preferably implementation of the invention, according to Fig.4, analysis circuit 4 includes：
Signal receiving module 41 is separately connected the output end of the output end I13 and reference signal circuit 42 of computing circuit 3,
For obtaining third current signal and judging signal；
Signal analysis module 43 is separately connected signal receiving module 41 and three-phase inverter, is used for third current signal
With judge that signal is compared, and the level letter of saltus step is exported to three-phase inverter when third current signal is more than reference signal
Number, to control the protection operation of three-phase inverter trigger current.
Specifically, in the present embodiment, reference signal be judge third current signal whether the signal value of overcurrent, third electricity
It flows signal and is more than reference signal, three-phase inverter is in over-current state at this time, and signal analysis module 43 exports the level letter of saltus step
Number, three-phase inverter is able to trigger circuit protection operation.
It is of the invention a kind of preferably to implement, a kind of electric machine controller, including a three-phase inverter, three-phase inverter include
Any of the above-described current protecting circuit.
The foregoing is merely preferred embodiments of the present invention, are not intended to limit embodiments of the present invention and protection model
It encloses, to those skilled in the art, should can appreciate that all with made by description of the invention and diagramatic content
Equivalent replacement and obviously change obtained scheme, should all be included within the scope of the present invention.
Claims (7)
1. a kind of current protecting circuit, which is characterized in that it is suitable for three-phase inverter, including：
First current-sensing circuit, the U phases that the input terminal of first current-sensing circuit connects the three-phase inverter export
End, the first current signal for obtaining the U phase output terminals；
Second current-sensing circuit, the W phases that the input terminal of second current-sensing circuit connects the three-phase inverter export
End, the second current signal for obtaining the W phase output terminals；
The input terminal of computing circuit, the computing circuit is separately connected the output end and described of first current-sensing circuit
The output end of two current-sensing circuits, for first current signal to be added to acquisition described three with second current signal
The third current signal of the V phase output terminals of phase inverter；
Analysis circuit connects the output end of the computing circuit, judges current signal for being more than in the third current signal
When, it triggers the three-phase inverter and carries out current protection operation；
Reference signal circuit, the input terminal of the reference signal circuit connect a constant voltage source, the reference signal circuit it is defeated
Outlet connects the analysis circuit, for generating the judgement current signal.
2. current protecting circuit according to claim 1, which is characterized in that first current-sensing circuit and described the
Two current-sensing circuits are identical current-sensing circuit,
Each current-sensing circuit includes respectively an inductor, the conducting wire of the U phase output terminals and leading for the W phase output terminals
Line is each passed through the induction coil in the corresponding inductor.
3. current protecting circuit according to claim 2, which is characterized in that the current-sensing circuit further includes：
First capacitance, both ends are separately connected first node and second node；
First resistor, both ends are separately connected the first node and third node；
Second capacitance, both ends are separately connected the third node and fourth node；
Second resistance, both ends are separately connected the third node and the 5th node；
Third capacitance, both ends are separately connected the second node and the 6th node；
4th capacitance, both ends are separately connected the fourth node and the 6th node；
The signal output end of the inductor connects the first node, ground terminal connection second section of the inductor
The power input of point, the inductor connects the 6th node；
6th node is also connected with the constant voltage source, and the third node connects the output end of the current-sensing circuit,
The 5th node ground connection；
The fourth node is separately connected the second node and the 5th node.
4. current protecting circuit according to claim 1, which is characterized in that the computing circuit includes：
Comparator, for first current signal and second current signal to be summed up operation to obtain the third
Current signal；
3rd resistor, both ends are separately connected the output end and the 7th node of first current-sensing circuit；
4th resistance, both ends are separately connected the output end and the 7th node of second current-sensing circuit；
5th resistance, both ends are separately connected the 7th node and the 8th node；
5th capacitance, both ends are separately connected the 7th node and the 8th node；
6th capacitance, both ends are separately connected the 9th node and protelum point；
The normal phase input end of the comparator connects the output end of a biasing circuit, and the negative-phase input of the comparator connects institute
The 7th node is stated, the positive voltage input terminal of the comparator connects the 9th node, the negative voltage input terminal of the comparator
The protelum point is connected, the output end of the comparator connects the 8th node；
9th node connects the constant voltage source, the protelum point ground connection, and the 8th node connects the operation electricity
The output end on road.
5. current protecting circuit according to claim 4, which is characterized in that the biasing circuit includes：
Controlled rectifier connects the 11st node, anode the 13rd node of connection, the 12nd section of control pole connection described in cathode
Point；
7th capacitance, both ends are separately connected the 12nd node and the 13rd node；
6th resistance, both ends are separately connected the 12nd node and a constant voltage source.
The 13rd node ground connection, the 11st node connect the output end of the biasing circuit.
6. current protecting circuit according to claim 1, which is characterized in that the analysis circuit includes：
Signal receiving module is separately connected the output end of the output end and the reference signal circuit of the computing circuit, is used for
Obtain the third current signal and the judgement current signal；
Signal analysis module is separately connected the signal receiving module and the three-phase inverter, is used for the third electric current
Signal and the judgement current signal are compared, and when the third current signal is more than the judgement current signal to institute
The level signal for stating three-phase inverter output saltus step, to control the three-phase inverter trigger current protection operation.
7. a kind of electric machine controller, which is characterized in that including a three-phase inverter, the three-phase inverter includes such as claim
Any current protecting circuit in 1-6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810247716.XA CN108599094A (en) | 2018-03-23 | 2018-03-23 | A kind of current protecting circuit and electric machine controller |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810247716.XA CN108599094A (en) | 2018-03-23 | 2018-03-23 | A kind of current protecting circuit and electric machine controller |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108599094A true CN108599094A (en) | 2018-09-28 |
Family
ID=63627401
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810247716.XA Pending CN108599094A (en) | 2018-03-23 | 2018-03-23 | A kind of current protecting circuit and electric machine controller |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108599094A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1957521A (en) * | 2004-06-22 | 2007-05-02 | Smc电子产品有限公司 | Inverter bridge controller implementing short-circuit protection scheme |
| CN201860286U (en) * | 2010-08-03 | 2011-06-08 | 戴薇 | Control system for pumping unit in oil field |
| CN107611935A (en) * | 2017-09-28 | 2018-01-19 | 佛山市索尔电子实业有限公司 | A kind of inverter circuit with overcurrent protection function |
-
2018
- 2018-03-23 CN CN201810247716.XA patent/CN108599094A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1957521A (en) * | 2004-06-22 | 2007-05-02 | Smc电子产品有限公司 | Inverter bridge controller implementing short-circuit protection scheme |
| CN201860286U (en) * | 2010-08-03 | 2011-06-08 | 戴薇 | Control system for pumping unit in oil field |
| CN107611935A (en) * | 2017-09-28 | 2018-01-19 | 佛山市索尔电子实业有限公司 | A kind of inverter circuit with overcurrent protection function |
Non-Patent Citations (1)
| Title |
|---|
| 秦海鸥，严仰光: "《多电飞机的电气系统》", 31 March 2016, 北京航空航天大学出版社 * |
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