CN202535041U - Short-circuit protecting circuit of high-power photovoltaic inverter - Google Patents
Short-circuit protecting circuit of high-power photovoltaic inverter Download PDFInfo
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- CN202535041U CN202535041U CN2012201266422U CN201220126642U CN202535041U CN 202535041 U CN202535041 U CN 202535041U CN 2012201266422 U CN2012201266422 U CN 2012201266422U CN 201220126642 U CN201220126642 U CN 201220126642U CN 202535041 U CN202535041 U CN 202535041U
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Abstract
Disclosed in the utility model is a short-circuit protecting circuit of a high-power photovoltaic inverter, wherein the short-circuit protecting circuit comprises a high-power photovoltaic inverter, an alternating current sampling circuit, a signal conditioning circuit, an absolute value and maximum value solving circuit, a reference voltage generating circuit, a current threshold detection circuit, an optical coupling isolation circuit, a DSP control module, and a switch tube driving module. The current sampling device includes hall current sensors and sampling resistors; and the reference voltage generating circuit includes a plurality of reference voltage divider resistors. According to the utility model, the hall current sensors with fast responding speeds and high measuring precision are utilized to carry out sampling on output instantaneous current values of the inverter. The whole protecting circuit is formed by conventional hardware circuits; the motion speed is fast and secure and reliable performances are realized; the utilization of a general integrated current protection module can be avoided. The short-circuit protecting circuit can be used for photovoltaic inverters with different power grades and can be used to solve short-circuit faults of different types; and the circuit has advantages of high detection sensitivity, fast protection motion and reliable execution.
Description
Technical field
The utility model relates generally to the photovoltaic new energy field, is specifically related to the short-circuit protection technology of high-power photovoltaic DC-to-AC converter.
Background technology
In the high-power photovoltaic DC-to-AC converter; In circuit since control circuit be interfered or load faulty causes the bridge arm direct pass short circuit; Need to cut off, if untimely, energy stored will discharge through short-circuit component in a short period of time on the capacitor at once; If this discharging current surpasses when running through the surge capacity of short-circuit component, will make component wear.Short-circuit protection circuit is a kind of a kind of circuit that the protection entire circuit is not damaged it during big electric current of in circuit, flowing through.
1. the prior art scheme one directly related with the present invention:
1.1 the content of prior art scheme one
The short-circuit protection that photovoltaic DC-to-AC converter is commonly used at present mainly contains two kinds of schemes, and wherein scheme one is as shown in Figure 1, is indirect voltage method.Fig. 1 is the short-circuit protection circuit that the principle of the Vce increase of IGBT when utilizing the IGBT overcurrent realizes.
As shown in Figure 1, short-circuit protection circuit comprises IC1, IC2, VD1 etc., and wherein, IC1 is a comparator, and described IC1 can be LM339; IC2 is the special-purpose drive circuit that is used for IGBT, and described IC2 can be EXB841; VD1, VD2 are fast recovery diodes.The EXB841 internal circuit can be accomplished well and fall grid voltage and soft shutoff, and has the internal latency function, disturbs the misoperation that produces to eliminate.
As shown in Figure 1, described short-circuit protection circuit carries out short circuit through the Vce voltage swing that detects corresponding IGBT between the driving pulse high period and judges; Characteristic by IGBT can be known; When IGBT opened, its C, E voltage and its electric current that passes through had linear relationship, and the Vce when detecting overcurrent or short circuit also compares with preset threshold; With the shutoff of the output control Driver Circuit of comparator, can accomplish overcurrent protection.
As shown in Figure 1, if be short-circuited, contain the IGBT collector voltage that Vce that IGBT crosses stream information directly do not deliver to IC2 and keep watch on pin---on 6 pin; But turn-off VD1 fast, and so that make the V+ voltage of comparator IC1 greater than V-voltage, comparator output high level; Deliver to 6 pin of IC2 by VD2; Its objective is in order to eliminate the VD1 forward voltage drop differently and different, adopt threshold value comparator IC1, improve the accuracy of current detecting with electric current.
As shown in Figure 1; If generation overcurrent; Start and to fall grid voltage and soft breaking circuit in the IC2 internal circuit, thereby the low speed of driver IC 2 cuts off circuit the 3 pin current potentials of IC2 are also progressively descended, and then turn-off IGBT at a slow speed; Both avoid the collector current spike to damage IGBT, accomplished the IGBT short-circuit protection again.
1.2 the shortcoming of prior art scheme 1
Saturation voltage drop Vce through detecting IGBT realizes short-circuit protection; It often need cooperate drive circuit IC2, and for example EXB841 realizes; This makes underaction when circuit design; Simultaneously Vce detects and can not protect fully short circuit or overcurrent, and this is because load such as the motor of overcurrent after to IGBT etc. are unallowable, and the very big rising of forward voltage drop is limited by desaturation function only; If this pressure drop does not reach critical point, controlled function just is not sure of short circuit has been taken place.
2. the prior art scheme two directly related with the present invention:
2.1 the content of prior art scheme two
The short-circuit protection scheme two of photovoltaic DC-to-AC converter, as shown in Figure 2, for detecting the bus current method.
Fig. 2 is the bridge arm direct pass short-circuit protection circuit, and it comprises three-phase alternating-current supply ea, eb, ec, DC power supply DC+, DC-, and IGBT switch transistor T 1, T2, T3, T4, T5, T6, AC side Hall current sensor IT1, IT2, IT3 reach inductance L a, Lb, Lc etc.Wherein Ip is the brachium pontis bus current; Ia, ib, ic are three-phase alternating current.
As shown in Figure 2, when detecting, short-circuit protection circuit just thinks when brachium pontis bus current Ip increases to the certain multiple rated current suddenly the bridge arm direct pass fault takes place that the driving that block all IGBT this moment eliminating fault, thereby avoids IGBT to burn.
2.2 the shortcoming of prior art scheme two
The testing circuit of scheme two is applicable in the single-phase low capacity converter.For three-phase inverter or big capacity converter, because the rated current of brachium pontis bus current Ip is bigger, during single-phase bridge arm direct pass, before IGBT damaged, brachium pontis bus current Ip changed not too obvious, can not implement effective protection.
3. brief summary:
In sum, to the deficiency of current foldback circuit in the prior art, in order to solve the short-circuit protection problem of high-power photovoltaic DC-to-AC converter, it is high to propose a kind of detection sensitivity, and the protection action is fast, carries out reliable short-circuit protection circuit, becomes problem demanding prompt solution.
Summary of the invention
The purpose of the utility model is, to the deficiency of current foldback circuit in the prior art, in order to solve the short-circuit protection problem of high-power photovoltaic DC-to-AC converter, and it is high to propose a kind of detection sensitivity, and the protection action is fast, carries out reliable short-circuit protection circuit.
For realizing above-mentioned purpose; The openly following technical scheme of the utility model: a kind of short-circuit protection circuit of high-power photovoltaic DC-to-AC converter; It comprises high-power photovoltaic DC-to-AC converter, alternating current sample circuit, signal conditioning circuit, asks absolute value and maximum value circuit, and reference voltage produces circuit, current threshold testing circuit; Optical coupling isolation circuit reaches DSP control module, switching tube driver module;
Wherein, described high-power photovoltaic DC-to-AC converter comprises a plurality of IGBT switching tubes;
The A of described high-power photovoltaic DC-to-AC converter, B, C three-phase output end are electrical connected with A, B, the C three-phase input end of described alternating current sample circuit respectively;
The A of described alternating current sample circuit, B, C three-phase output end are electrical connected with A, B, the C three-phase input end of described signal conditioning circuit respectively;
The A of described signal conditioning circuit, B, C three-phase output end are electrical connected with described A, B, the C three-phase input end of absolute value and maximum value circuit asked respectively;
Described reference voltage produces the output of circuit and second input of described current threshold testing circuit is electrical connected;
The described output of absolute value and maximum value circuit and the first input end of described current threshold testing circuit asked is electrical connected;
The output of described current threshold testing circuit and described optical coupling isolation circuit input are electrical connected;
The input of described optical coupling isolation circuit output and described DSP control module is electrical connected;
A plurality of PWM output pins of described DSP control module link to each other with the input pin of described switching tube driver module;
The grid of a plurality of IGBT switching tubes in the output pin of described switching tube driver module and the described high-power photovoltaic DC-to-AC converter links to each other respectively.
The short-circuit protection circuit of described high-power photovoltaic DC-to-AC converter, wherein, described alternating current sample circuit comprises a plurality of AC side Hall current sensors, a plurality of sampling resistor, a plurality of resistance, a plurality of electric capacity; Wherein, described a plurality of AC side Hall current sensor comprises first Hall current sensor, second Hall current sensor, the 3rd Hall current sensor; Described a plurality of sampling resistor comprises first resistance, the 11 resistance, the 21 resistance; Described a plurality of resistance comprises second resistance R 2, the 12 resistance, the 22 resistance, and described a plurality of electric capacity comprise first capacitor C 1, the 11 electric capacity, the 21 electric capacity;
Wherein, first end of first Hall current sensor is the A phase input of alternating current sample circuit; Second end of first Hall current sensor links to each other with first end of first end of first resistance and second resistance; The second end ground connection of first resistance; The second end ground connection of first electric capacity; Second end of second resistance links to each other the back as the A phase output terminal of alternating current sample circuit with first end of first electric capacity;
First end of second Hall current sensor is the B phase input of alternating current sample circuit; Second end of second Hall current sensor links to each other with first end of the 11 resistance and first end of the 12 resistance; The second end ground connection of the 11 resistance; The second end ground connection of the 11 electric capacity; Second end of the 12 resistance links to each other the back as the B phase output terminal of alternating current sample circuit with first end of the 11 electric capacity;
First end of the 3rd Hall current sensor is the C phase input of alternating current sample circuit; Second end of the 3rd Hall current sensor links to each other with first end of the 21 resistance and first end of the 22 resistance; The second end ground connection of the 21 resistance; The second end ground connection of the 21 electric capacity; Second end of the 22 resistance links to each other the back as the C phase output terminal of alternating current sample circuit with first end of the 21 electric capacity.
The short-circuit protection circuit of described high-power photovoltaic DC-to-AC converter wherein, comprises A phase computing amplifying return circuit, B phase computing amplifying return circuit, C phase computing amplifying return circuit and a plurality of voltage follower in the described signal conditioning circuit; Wherein, voltage follower comprises second amplifier, the 12 amplifier, the 22 amplifier; A phase computing amplifying return circuit comprises first amplifier, the 3rd resistance, the 4th resistance; B phase computing amplifying return circuit comprises the 11 amplifier, the 13 resistance, the 14 resistance, and C phase computing amplifying return circuit comprises the 21 amplifier, the 23 resistance, the 24 resistance;
Wherein, first amplifier, the 11 amplifier, the 21 amplifier and second amplifier, the 12 amplifier, the 22 amplifier are LM258;
The in-phase end of first amplifier is the A phase input of signal conditioning circuit; First end of the 3rd resistance links to each other with first end of the end of oppisite phase of first amplifier and the 4th resistance; The second end ground connection of the 3rd resistance; Second end of the 4th resistance links to each other with the in-phase end of the output of first amplifier and second amplifier; The second end ground connection of the 5th resistance; The end of oppisite phase of second amplifier links to each other with the output of second amplifier and first end of the 5th resistance, and as the A phase output terminal of signal conditioning circuit;
The in-phase end of the 11 amplifier is the B phase input of signal conditioning circuit; First end of the 13 resistance links to each other with the end of oppisite phase of the 11 amplifier and first end of the 14 resistance; The second end ground connection of the 13 resistance; Second end of the 14 resistance links to each other with the output of the 11 amplifier and the in-phase end of the 12 amplifier; The second end ground connection of the 15 resistance; The end of oppisite phase of the 12 amplifier links to each other with first end of the output of the 12 amplifier and the 15 resistance, and as the B phase output terminal of signal conditioning circuit;
The in-phase end of the 21 amplifier is the C phase input of signal conditioning circuit; First end of the 23 resistance links to each other with the end of oppisite phase of the 21 amplifier and first end of the 24 resistance; The second end ground connection of the 23 resistance; Second end of the 24 resistance links to each other with the output of the 21 amplifier and the in-phase end of the 22 amplifier; The second end ground connection of the 25 resistance; The end of oppisite phase of the 22 amplifier links to each other with first end of the output of the 22 amplifier and the 25 resistance, and as the C phase output terminal of signal conditioning circuit.
The short-circuit protection circuit of described high-power photovoltaic DC-to-AC converter, wherein, described reference voltage produces circuit and comprises a plurality of reference voltage divider resistances, reference voltage chip and an operational amplifier---the 41 amplifier; Wherein, described reference voltage chip is LM236AZ5; Described a plurality of reference voltage divider resistance comprises the 43 resistance, the 44 resistance;
The first pin ground connection of reference voltage chip; The 3rd pin open circuit of reference voltage chip; Second pin of reference voltage chip links to each other with first end of first end of the 39 resistance, the 7th electric capacity and first end of the 40 resistance; Second end of the 39 resistance links to each other with+15 voltage sources; The second end ground connection of the 7th electric capacity; The in-phase end of the 41 amplifier links to each other with second end of the 40 resistance; The end of oppisite phase of the 41 amplifier links to each other with first end of second end of the 41 resistance and the 42 resistance; The first end ground connection of the 41 resistance; The output of the 41 amplifier links to each other with first end of second end of the 42 resistance and the 43 resistance; The second end ground connection of the 44 resistance; Second end of the 43 resistance links to each other with first end of the 44 resistance, produces the output of circuit as reference voltage.
The short-circuit protection circuit of described high-power photovoltaic DC-to-AC converter; Wherein, Described current threshold testing circuit comprises a voltage comparator---the 5th amplifier, a plurality of resistance and an electric capacity---the 9th electric capacity, wherein, voltage comparator---the 5th amplifier is comparator LM2903; Described a plurality of resistance does---the tenth resistance, the 45 resistance;
The tenth resistance first end is the first input end of current threshold testing circuit; Second end of the tenth resistance links to each other with the end of oppisite phase of first end of the 9th electric capacity and the 5th amplifier; The second end ground connection of the 9th electric capacity; First end of the 45 resistance is second input of current threshold testing circuit; First end of the 45 resistance links to each other with the output of the 5th amplifier, as the output of current threshold testing circuit.
The short-circuit protection circuit of described high-power photovoltaic DC-to-AC converter, wherein, described optical coupling isolation circuit can comprise rapid light coupling chip, the 3rd diode, the 4th diode and the 46 resistance; Wherein, described rapid light coupling chip is TLP559;
The input of optical coupling isolation circuit is the negative pole of the 3rd diode; The output of current threshold testing circuit links to each other with the negative pole of the 3rd diode; The positive pole of the 3rd diode links to each other with the former limit light-emitting diode negative pole end of rapid light coupling chip and the positive pole of the 4th diode; Former limit light-emitting diode positive terminal and the negative pole of the 4th diode and first end of the 46 resistance of rapid light coupling chip links to each other; Second end of the 46 resistance links to each other with+15V power supply; The grounded emitter of the secondary phototriode of rapid light coupling chip; Second end of the 47 resistance links to each other with+5V power supply; The collector electrode of the secondary phototriode of rapid light coupling chip links to each other with first end of the 46 resistance, as the output of optical coupling isolation circuit.
The short-circuit protection circuit of described high-power photovoltaic DC-to-AC converter, wherein, described DSP control module comprises level transferring chip and dsp chip;
Wherein, level transferring chip is 74LVC4245, and dsp chip is TMS320F2812;
First end of level transferring chip is the input of DSP control module; Second end of level transferring chip links to each other with the PDPINTA pin of dsp chip;
The output that a plurality of PWM output pins of described dsp chip are described DSP control modules.
The beneficial effect of the utility model is, to the deficiency of current foldback circuit in the prior art, in order to solve the short-circuit protection problem of high-power photovoltaic DC-to-AC converter, and it is high to have proposed a kind of detection sensitivity, and the protection action is fast, carries out reliable short-circuit protection circuit.The utility model comes high-power photovoltaic DC-to-AC converter is carried out short-circuit protection through direct current detecting, can effectively prevent short circuit and overcurrent, has improved fail safe greatly, has reduced cost; When the inverter output short-circuit, can block the IGBT switching tube of conducting fast, miscellaneous equipments such as protection IGBT switching tube are without prejudice, and short-circuit protection is timely, and reliability is high.
Description of drawings
Fig. 1 is that the Vce of IGBT when utilizing overcurrent increases the short-circuit protection circuit sketch map of realizing;
Fig. 2 is a bridge arm direct pass short-circuit protection circuit sketch map;
Fig. 3 is a photovoltaic DC-to-AC converter short-circuit protection block diagram;
Fig. 4 is a photovoltaic DC-to-AC converter short-circuit protection detailed circuit schematic.
Embodiment
Below in conjunction with accompanying drawing, do more detailed explanation with other technical characterictic and advantage to the utility model is above-mentioned.
See also Fig. 3; As shown in Figure 3, the present invention discloses a kind of short-circuit protection circuit of high-power photovoltaic DC-to-AC converter, and it comprises high-power photovoltaic DC-to-AC converter 300, alternating current sample circuit 301, signal conditioning circuit 302, asks absolute value and maximum value circuit 303; Reference voltage produces circuit 304; Current threshold testing circuit 305, optical coupling isolation circuit 306 reaches DSP control module 307, switching tube driver module 308;
Wherein, described high-power photovoltaic DC-to-AC converter 300 comprises a plurality of IGBT switching tubes;
Described high-power photovoltaic DC-to-AC converter 300 is electrical connected with described alternating current sample circuit 301;
Described alternating current sample circuit 301 is electrical connected with described signal conditioning circuit 302;
Described signal conditioning circuit 302 is electrical connected with described absolute value and the maximum value circuit 303 asked;
Described reference voltage produces circuit 304 and is electrical connected with described current threshold testing circuit 305;
Described absolute value and the maximum value circuit 303 asked is electrical connected with described current threshold testing circuit 30;
Described current threshold testing circuit 305 is electrical connected with described optical coupling isolation circuit 306;
Described optical coupling isolation circuit 306 is electrical connected with described DSP control module 307.
A plurality of PWM output pins of described DSP control module 307 link to each other with the input pin of described switching tube driver module 308;
The grid of a plurality of IGBT switching tubes in the output pin of described switching tube driver module 308 and the described high-power photovoltaic DC-to-AC converter 300 links to each other respectively.
(1) high-power photovoltaic DC-to-AC converter 300:
As shown in Figure 4, the transient current ia of high-power photovoltaic DC-to-AC converter 300 output A, B, C three-phase, ib, ic are to alternating current sample circuit 301;
Fig. 4 is the embodiment of Fig. 3.See also the short-circuit protection circuit of the high-power photovoltaic DC-to-AC converter of Fig. 3 and Fig. 4 below, wherein, described high power contravariant device 300 comprises a direct current power supply and an inverter; Described DC power supply comprises a solar generator SG (figure does not show) and a capacitor C 1, and described DC power supply, its positive pole are designated as DC+, its negative pole is designated as DC-; Described inverter 2 comprises: six IGBT switching tubes---first switch transistor T 1, second switch pipe T2, the 3rd switch transistor T 3, the 4th switch transistor T 4, the 5th switch transistor T 5, the 6th switch transistor T 6 and six diodes---the 101 diode D101, the 102 diode D102, the 103 diode D103, the 104 diode D104, the 105 diode D105, the 106 diode D106; Wherein, Described six diodes---the 101 diode D101, the 102 diode D102, the 103 diode D103, the 104 diode D104, the 105 diode D105, the 106 diode D106; Be connected anti-parallel to described six IGBT switching tubes respectively---the two ends of first switch transistor T 1, second switch pipe T2, the 3rd switch transistor T 3, the 4th switch transistor T 4, the 5th switch transistor T 5, the 6th switch transistor T 6, promptly the 101 diode D101 is connected anti-parallel to the two ends of first switch transistor T 1, the two ends that the 102 diode D102 is connected anti-parallel to second switch pipe T2, the two ends that the 103 diode D103 is connected anti-parallel to the 3rd switch transistor T 3, the two ends that the 104 diode D104 is connected anti-parallel to the 4th switch transistor T 4, the two ends that the 105 diode D105 is connected anti-parallel to the 5th switch transistor T 5, the two ends that the 106 diode D106 is connected anti-parallel to the 6th switch transistor T 6;
Said six IGBT switching tubes---first switch transistor T 1, second switch pipe T2, the 3rd switch transistor T 3, the 4th switch transistor T 4, the 5th switch transistor T 5, the 6th switch transistor T 6 have an one source pole and a drain electrode respectively,
The anodal DC+ of described DC power supply links to each other with the drain electrode of the drain electrode of first end of described capacitor C 1, said first switch transistor T 1, said second switch pipe T2, the drain electrode of said the 3rd switch transistor T 3;
The negative pole DC-of described DC power supply links to each other with the source electrode of the source electrode of second end of described capacitor C 1, described the 4th switch transistor T 4, described the 5th switch transistor T 5, the source electrode of described the 6th switch transistor T 6;
After the drain electrode of the source electrode of said first switch transistor T 1 and described the 4th switch transistor T 4 is electrical connected,, export the A phase output current ia of described high-power photovoltaic DC-to-AC converter 300 as the A phase output terminal of high-power photovoltaic DC-to-AC converter 300;
After the source electrode of said second switch pipe T2 and the drain electrode of described the 5th switch transistor T 5 are electrical connected,, export the B phase output current ib of described high-power photovoltaic DC-to-AC converter 300 as the B phase output terminal of high-power photovoltaic DC-to-AC converter 300;
After the drain electrode of the source electrode of said the 3rd switch transistor T 3 and described the 6th switch transistor T 6 is electrical connected,, export the C phase output current ic of described high-power photovoltaic DC-to-AC converter 300 as the C phase output terminal of high-power photovoltaic DC-to-AC converter 300.
(2) the alternating current sample circuit 301:
As shown in Figure 4; After a plurality of Hall current sensors of alternating current sample circuit 301---the first Hall current sensor IT1, the second Hall current sensor IT2, the 3rd Hall current sensor IT3 sample to described A, B, the transient current ia of C three-phase, ib, ic respectively; Receive sampled value and also deliver to the sample circuit of A, B, C three-phase respectively; Alternating current sample circuit 301 is through sampling resistor---first resistance R 1 (ia sampling resistor); The 11 resistance R 11 (ib sampling resistor); The 21 resistance R 21 (ic sampling resistor), with described sampled value be converted into-5 of A, B, C three-phase～+ voltage signal of 5V, wherein; To the photovoltaic DC-to-AC converter of different capacity, only need revise sampling resistor---the resistance of first resistance R the 1, the 11 resistance R 11, the 21 resistance R 21 can realize short-circuit protection function; Described then-5～+ the 5V voltage signal is through second resistance R 2, first capacitor C 1 (ia filtering); The 12 resistance R the 12, the 11 capacitor C 11 (ib filtering) outputs to signal conditioning circuit 302 after the 21, the 21 capacitor C 21 (ic filtering) filtering of the 21 resistance R;
Fig. 4 is the embodiment of Fig. 3.See also the short-circuit protection circuit of the high-power photovoltaic DC-to-AC converter of Fig. 3 and Fig. 4 below, wherein, described alternating current sample circuit 301 comprises a plurality of AC side Hall current sensors, a plurality of sampling resistor, a plurality of resistance, a plurality of electric capacity; Wherein, a plurality of AC side Hall current sensors comprise the first Hall current sensor IT1, the second Hall current sensor IT2, the 3rd Hall current sensor IT3; A plurality of sampling resistors comprise first resistance R the 1, the 11 resistance R the 11, the 21 resistance R 21; A plurality of resistance comprise second resistance R the 2, the 12 resistance R the 12, the 22 resistance R 22, and a plurality of electric capacity comprise first capacitor C the 1, the 11 capacitor C the 11, the 21 capacitor C 21;
First end of the first Hall current sensor IT1 is the A phase input of alternating current sample circuit; The A phase output terminal of high-power photovoltaic DC-to-AC converter 300 links to each other with first end of the first Hall current sensor IT1; Second end of the first Hall current sensor IT1 links to each other with first end of first resistance R 1 and first end of second resistance R 2; The second end ground connection of first resistance R 1; The second end ground connection of first capacitor C 1; Second end of second resistance R 2 links to each other the back as the A phase output terminal of alternating current sample circuit 301 with first end of first capacitor C 1; Wherein, In the A of alternating current sample circuit 301 phase branch road; After the first Hall current sensor IT1 samples to the transient current ia of described A phase, receive sampled value and deliver to the sample circuit of A phase, alternating current sample circuit 301 is sampled through 1 couple of ia of first resistance R; With described sampled value be converted into-5 of A phase～+ voltage signal of 5V; Wherein, to the photovoltaic DC-to-AC converter of different capacity, only need revising, the resistance of sampling resistor first resistance R 1 can realize short-circuit protection function; Described then-5～+ the 5V voltage signal carries out outputing to signal conditioning circuit 302 after the ia filtering through second resistance R 2,1 pair of first capacitor C;
First end of the second Hall current sensor IT2 is the B phase input of alternating current sample circuit; The B phase output terminal of high-power photovoltaic DC-to-AC converter 300 links to each other with first end of the second Hall current sensor IT2; Second end of the second Hall current sensor IT2 links to each other with first end of first end of the 11 resistance R 11 and the 12 resistance R 12; The second end ground connection of the 11 resistance R 11; The second end ground connection of the 11 capacitor C 11; Second end of the 12 resistance R 12 links to each other the back as the B phase output terminal of alternating current sample circuit 301 with first end of the 11 capacitor C 11; Wherein, In the B of alternating current sample circuit 301 phase branch road; After the second Hall current sensor IT2 samples to the transient current ib of described B phase, receive sampled value and deliver to the sample circuit of B phase, alternating current sample circuit 301 is sampled through 11 couples of ib of the 11 resistance R; With described sampled value be converted into-5 of B phase～+ voltage signal of 5V; Wherein, to the photovoltaic DC-to-AC converter of different capacity, only need revising, the resistance of sampling resistor the 11 resistance R 11 can realize short-circuit protection function; Described then-5～+ the 5V voltage signal carries out outputing to signal conditioning circuit 302 after the ib filtering through the 12 resistance R the 12, the 11 11 pairs of capacitor C;
First end of the 3rd Hall current sensor IT3 is the C phase input of alternating current sample circuit; The C phase output terminal of high-power photovoltaic DC-to-AC converter 300 links to each other with first end of the 3rd Hall current sensor IT3; Second end of the 3rd Hall current sensor IT3 links to each other with first end of first end of the 21 resistance R 21 and the 22 resistance R 22; The second end ground connection of the 21 resistance R 21; The second end ground connection of the 21 capacitor C 21; Second end of the 22 resistance R 22 links to each other the back as the C phase output terminal of alternating current sample circuit 301 with first end of the 21 capacitor C 21; Wherein, In the C of alternating current sample circuit 301 phase branch road; After the 3rd Hall current sensor IT3 samples to the transient current ic of described C phase, receive sampled value and deliver to the sample circuit of C phase, alternating current sample circuit 301 is sampled through 21 couples of ic of the 21 resistance R; With described sampled value be converted into-5 of C phase～+ voltage signal of 5V; Wherein, to the photovoltaic DC-to-AC converter of different capacity, only need revising, the resistance of sampling resistor the 21 resistance R 21 can realize short-circuit protection function; Described then-5～+ the 5V voltage signal carries out outputing to signal conditioning circuit 302 after the ic filtering through the 22 resistance R the 22, the 21 21 pairs of capacitor C.
(3) signal conditioning circuit 302:
As shown in Figure 4; Signal conditioning circuit 302 receive described alternating current sample circuit 301 outputs A, B, C three-phase-5～+ the 5V voltage signal after; After carrying out the computing processing and amplifying through three-phase computing amplifying return circuit respectively, with-5 of described A, B, C three-phase～+ the 5V voltage signal be converted into-10 of A, B, C three-phase～+ voltage signal of 10V; Then-10 of A, B, C three-phase～+ voltage signal of 10V delivers to the voltage follower second amplifier U2, the 12 amplifier U12, the 22 amplifier U22 with after improving input impedance, reducing output impedance ,-10 of output A, B, C three-phase～+ voltage signal of 10V is to asking absolute value and maximum value circuit 303;
Fig. 4 is the embodiment of Fig. 3.See also the short-circuit protection circuit of the high-power photovoltaic DC-to-AC converter of Fig. 3 and Fig. 4 below, wherein, comprise A phase computing amplifying return circuit in the described signal conditioning circuit 302, B phase computing amplifying return circuit, C phase computing amplifying return circuit and a plurality of voltage follower; Wherein, voltage follower comprises the second amplifier U2, the 12 amplifier U12, the 22 amplifier U22; A phase computing amplifying return circuit comprises the first amplifier U1, the 3rd resistance R 3, the 4th resistance R 4; B phase computing amplifying return circuit comprises the 11 amplifier U11, the 13 resistance R the 13, the 14 resistance R 14, and C phase computing amplifying return circuit comprises the 21 amplifier U21, the 23 resistance R the 23, the 24 resistance R 24;
Wherein, the first amplifier U1, the 11 amplifier U11, the 21 amplifier U21 and the second amplifier U2, the 12 amplifier U12, the 22 amplifier U22 can be LM258.
The in-phase end of the first amplifier U1 is the A phase input of signal conditioning circuit; The A phase output terminal of alternating current sample circuit 301 links to each other with the in-phase end of the first amplifier U1, and first end of the 3rd resistance R 3 links to each other with first end of the end of oppisite phase of the first amplifier U1 with the 4th resistance R 4; The second end ground connection of the 3rd resistance R 3; Second end of the 4th resistance R 4 links to each other with the in-phase end of the output of the first amplifier U1 and the second amplifier U2; The second end ground connection of the 5th resistance R 5; The end of oppisite phase of the second amplifier U2 links to each other with the output of the second amplifier U2 and first end of the 5th resistance R 5, and as the A phase output terminal of signal conditioning circuit 302.Wherein, As shown in Figure 4; Signal conditioning circuit 302 receive described alternating current sample circuit 301 outputs the A phase-5～+ the 5V voltage signal after; After carrying out the computing processing and amplifying through the A phase computing amplifying return circuit of forming by the first amplifier U1, the 3rd resistance R 3, the 4th resistance R 4, with-5 of described A phase～+ the 5V voltage signal be converted into-10 of A phase～+ voltage signal of 10V; Then-10 of A phase～+ voltage signal of 10V delivers to the voltage follower second amplifier U2 with after improving input impedance, reducing output impedance ,-10 of output A phase～+ voltage signal of 10V is to the A that asks absolute value and maximum value circuit 303 input mutually.
The in-phase end of the 11 amplifier U11 is the B phase input of signal conditioning circuit; The B phase output terminal of alternating current sample circuit 301 links to each other with the in-phase end of the 11 amplifier U11, and first end of the 13 resistance R 13 links to each other with first end of the end of oppisite phase of the 11 amplifier U11 and the 14 resistance R 14; The second end ground connection of the 13 resistance R 13; Second end of the 14 resistance R 14 links to each other with the output of the 11 amplifier U11 and the in-phase end of the 12 amplifier U12; The second end ground connection of the 15 resistance R 15; The end of oppisite phase of the 12 amplifier U12 links to each other with first end of the output of the 12 amplifier U12 and the 15 resistance R 15, and as the B phase output terminal of signal conditioning circuit 302.Wherein, As shown in Figure 4; Signal conditioning circuit 302 receive described alternating current sample circuit 301 outputs the B phase-5～+ the 5V voltage signal after; After carrying out the computing processing and amplifying through the B phase computing amplifying return circuit of forming by the 11 amplifier U11, the 13 resistance R the 13, the 14 resistance R 14, with-5 of described B phase～+ the 5V voltage signal be converted into-10 of B phase～+ voltage signal of 10V; Then-10 of B phase～+ voltage signal of 10V delivers to voltage follower the 12 amplifier U12 with after improving input impedance, reducing output impedance ,-10 of output B phase～+ voltage signal of 10V is to the B that asks absolute value and maximum value circuit 303 input mutually.
The in-phase end of the 21 amplifier U21 is the C phase input of signal conditioning circuit; The C phase output terminal of alternating current sample circuit 301 links to each other with the in-phase end of the 21 amplifier U21, and first end of the 23 resistance R 23 links to each other with first end of the end of oppisite phase of the 21 amplifier U21 and the 24 resistance R 24; The second end ground connection of the 23 resistance R 23; Second end of the 24 resistance R 24 links to each other with the output of the 21 amplifier U21 and the in-phase end of the 22 amplifier U22; The second end ground connection of the 25 resistance R 25; The end of oppisite phase of the 22 amplifier U22 links to each other with first end of the output of the 22 amplifier U22 and the 25 resistance R 25, and as the C phase output terminal of signal conditioning circuit 302.Wherein, As shown in Figure 4; Signal conditioning circuit 302 receive described alternating current sample circuit 301 outputs the C phase-5～+ the 5V voltage signal after; After carrying out the computing processing and amplifying through the C phase computing amplifying return circuit of forming by the 21 amplifier U21, the 23 resistance R the 23, the 24 resistance R 24, with-5 of described C phase～+ the 5V voltage signal be converted into-10 of C phase～+ voltage signal of 10V; Then-10 of C phase～+ voltage signal of 10V delivers to voltage follower the 22 amplifier U22 with after improving input impedance, reducing output impedance ,-10 of output C phase～+ voltage signal of 10V is to the B that asks absolute value and maximum value circuit 303 input mutually.
(4) ask absolute value and maximum value circuit 303:
As shown in Figure 4; Ask absolute value and maximum value circuit 303 to receive the voltage follower second amplifier U2 of described signal conditioning circuit 302; The 12 amplifier U12;-10 of the A of the 22 amplifier U22 output, B, C three-phase～+ signal of 10V after, earlier-10 of A, B, C three-phase～+ voltage signal of 10V be converted into 0 of A, B, C three-phase～+ voltage signal (promptly being converted into the steamed bun ripple) of 10V by sine wave; Ask absolute value and maximum value circuit 303 again to 0 of described A, B, C three-phase～+ the voltage signal maximizing of 10V, the maximum value signal of obtaining is outputed to current threshold testing circuit 305;
The A of described signal conditioning circuit 302, B, C three-phase output end are electrical connected with described A, B, the C three-phase input end of absolute value and maximum value circuit 303 asked respectively;
The described output of absolute value and maximum value circuit 303 and the first input end of described current threshold testing circuit 304 asked is electrical connected.
(5) the current threshold testing circuit 305:
As shown in Figure 4; After current threshold testing circuit 305 receives the described maximum value signal of asking 303 outputs of absolute value and maximum value circuit; The tenth resistance R 10, the 9th capacitor C 9 are earlier to the input voltage comparator---and the maximum value signal before the 5th amplifier U5 carries out filtering; Filtering spike burr, the false alarm of avoiding the spike burr to cause; Voltage comparator the 5th amplifier U5 of current threshold testing circuit 305 compares filtered maximum value signal and given reference voltage level; When described maximum value signal during greater than described given reference voltage level; Saltus step can take place in the output level of voltage comparator the 5th amplifier U5 of current threshold testing circuit 305; Become low level signal, output to optical coupling isolation circuit 306;
Fig. 4 is the embodiment of Fig. 3.See also the short-circuit protection circuit of the high-power photovoltaic DC-to-AC converter of Fig. 3 and Fig. 4 below; Wherein, The 9th capacitor C 9 that described current threshold testing circuit 305 comprises a voltage comparator---the 5th amplifier U5, a plurality of resistance and an electric capacity---; Wherein, voltage comparator---the 5th amplifier U5 can be comparator LM2903; Described a plurality of resistance does---the tenth resistance R the 10, the 45 resistance R 45; Wherein, the 45 resistance R 45 also is a reference voltage divider resistance.
First end of the tenth resistance R 10 is the first input end of current threshold testing circuit 305, and it links to each other with the output of maximum value circuit with asking absolute value; Ask the maximum value signal of absolute value and maximum value circuit 303 outputs promptly from then on to hold inflow current threshold detection circuit 305; Second end of the tenth resistance R 10 links to each other with first end of the 9th capacitor C 9 and the end of oppisite phase of the 5th amplifier U5; The second end ground connection of the 9th capacitor C 9; First end of the 45 resistance R 45 is second input of current threshold testing circuit 305; It links to each other with the output that reference voltage produces circuit 304, i.e. the output of reference voltage generation circuit 304 links to each other with first end of the 45 resistance R 45; First end of the 45 resistance R 45 links to each other with the output of the 5th amplifier U5, as the output of current threshold testing circuit 305.
(6) reference voltage produces circuit 304:
Fig. 4 is the embodiment of Fig. 3.See also the short-circuit protection circuit of the high-power photovoltaic DC-to-AC converter of Fig. 3 and Fig. 4 below; Wherein, described reference voltage produces circuit 304 and comprises a plurality of reference voltage divider resistances, reference voltage chip and an operational amplifier---the 41 amplifier U41; Wherein, described reference voltage chip can be LM236AZ5; Described a plurality of reference voltage divider resistance comprises the 43 resistance R the 43, the 44 resistance R 44.
First pin, 1 ground connection of reference voltage chip; The 3rd pin 3 open circuits of reference voltage chip; Second pin 2 of reference voltage chip links to each other with first end of first end of the 39 resistance R 39, the 7th capacitor C 7 and first end of the 40 resistance R 40; Second end of the 39 resistance R 39 links to each other with+15 voltage sources; The second end ground connection of the 7th capacitor C 7; The in-phase end of the 41 amplifier U41 links to each other with second end of the 40 resistance R 40; The end of oppisite phase of the 41 amplifier U41 links to each other with second end of the 41 resistance R 41 and first end of the 42 resistance R 42; The first end ground connection of the 41 resistance R 41; The output of the 41 amplifier U41 links to each other with second end of the 42 resistance R 42 and first end of the 43 resistance R 43; The second end ground connection of the 44 resistance R 44; Second end of the 43 resistance R 43 links to each other with first end of the 44 resistance R 44, produces the output of circuit 304 as reference voltage.
As shown in Figure 4, reference voltage produces circuit 304 provides 10V for current threshold testing circuit 305 reference voltage; Its principle is to export the 5V reference voltage to operational amplifier by second pin, 2 pin of reference voltage chip LM236AZ5---the 41 amplifier U41; After amplifying 2 times, the described 5V reference voltage that operational amplifier---the 41 amplifier U41 will receive becomes the 44 resistance R 44 places that the 10V reference voltage outputs to current threshold testing circuit 305; Then through the 43 resistance R 43; The 44 resistance R 44; The 45 resistance R 45 proportionate relationships are obtained the comparator in the current threshold testing circuit 305---and the reference voltage of the 5th amplifier U5 outputs to light-coupled isolation electric current 306 in the optical coupling isolation circuit 306; Wherein, the resistance of---the 43 resistance R 43, the 44 resistance R 44, the 45 resistance R 45---can realize short-circuit protection function to the photovoltaic DC-to-AC converter of different capacity, only need to revise reference voltage divider resistance; Wherein, if comparator U5 realizes that with LM2903 then the output in-phase input end of comparator the 5th amplifier U5 is equivalent to the 3rd pin 3 pin of comparator LM2903; The inverting input of comparator the 5th amplifier U5 is equivalent to second pin 2 of comparator LM2903; The output of comparator the 5th amplifier U5 is equivalent to first pin 1 of comparator LM2903.
(7) optical coupling isolation circuit 306:
Fig. 4 is the embodiment of Fig. 3.See also the short-circuit protection circuit of the high-power photovoltaic DC-to-AC converter of Fig. 3 and Fig. 4 below, wherein, described optical coupling isolation circuit 306 can comprise rapid light coupling chip, the 3rd diode D3, the 4th diode D4 and the 46 resistance R 46; Wherein, described rapid light coupling chip can be TLP559;
The input of optical coupling isolation circuit 306 is the negative pole of the 3rd diode D3; The output of current threshold testing circuit 305 links to each other with the negative pole of the 3rd diode D3; The positive pole of the 3rd diode D3 links to each other with the former limit light-emitting diode negative pole end of rapid light coupling chip and the positive pole of the 4th diode D4; Former limit light-emitting diode positive terminal and the negative pole of the 4th diode D4 and first end of the 46 resistance R 46 of rapid light coupling chip links to each other; Second end of the 46 resistance R 46 links to each other with+15V power supply; The grounded emitter of the secondary phototriode of rapid light coupling chip; Second end of the 47 resistance R 47 links to each other with+5V power supply; The collector electrode of the secondary phototriode of rapid light coupling chip links to each other with first end of the 46 resistance R 46, as the output of optical coupling isolation circuit 306, is electrical connected with the input of described DSP control module.
As shown in Figure 4, after optical coupling isolation circuit 306 received the low level signal of current threshold testing circuit 305 outputs, wherein, optical coupling isolation circuit 306 adopted rapid light coupling chip TLP559 that guard signal is isolated; Concrete principle is: when the output of comparator the 5th amplifier U5 was output as low level, the rapid light coupling chip made the conducting of former limit through the 3rd diode D3, and secondary output becomes low level, and system gets into guard mode.Low level signal through optocoupler output is outputed to DSP control module 307.
(8) DSP control module 307 and switching tube driver module 308:
Fig. 4 is the embodiment of Fig. 3.See also the short-circuit protection circuit of the high-power photovoltaic DC-to-AC converter of Fig. 3 and Fig. 4 below, wherein, described DSP control module 307 can comprise that dsp chip and level shift chip;
Wherein, dsp chip can be TMS320F2812, and level transferring chip can be 74LVC4245;
Wherein, TMS320F2812 comprises I/O mouth, PDPINTA pin and a plurality of PWM output pin (as shown in Figure 4); First end of level transferring chip 74LVC4245 is the input of DSP control module 307; Second end of level transferring chip 74LVC4245 links to each other with the PDPINTA pin of dsp chip TMS320F2812.
A plurality of PWM output pins (as shown in Figure 4) of described DSP control module 307 (like Fig. 3, shown in Figure 4) link to each other with the input pin of described switching tube driver module 308 (as shown in Figure 3, Fig. 4 does not show);
The grid of six IGBT switching tubes in the output pin of described switching tube driver module 308 and the described high-power photovoltaic DC-to-AC converter 300---first switch transistor T 1, second switch pipe T2, the 3rd switch transistor T 3, the 4th switch transistor T 4, the 5th switch transistor T 5, the 6th switch transistor T 6 links to each other respectively.
Wherein, be circuit safety reliably working in the assurance system, TMS320F2812 provides PDPINTA input signal, utilizes it can realize defencive function easily.As shown in Figure 4, the level transferring chip 74LVC4245 in the DSP control module 307 changes into signal on the PDPINTA pin of delivering to DSP behind the 3.3V level; When having any malfunction to occur; The level transferring chip 74LVC4245 of optical coupling isolation circuit 306 process DSP control modules 307 is to the dsp chip TMS320F2812 of DSP control module 307 input pin---and PDPINTA pin output low level, PDPINTA pin are also drawn to be low level; At this moment, the timer in the TMS320F2812 stops counting immediately, and all PWM output pins all are high-impedance state. and produce interrupt signal simultaneously, the CPU of notice TMS320F2812 has abnormal conditions to take place.Whole process does not need the program intervention, all accomplishes automatically, and this is very useful to the fast processing that realizes various malfunctions.
Wherein, PWM output pin high-impedance state is described PWM output pin and is cut-off state.
As shown in Figure 4; Because the I/O mouth of the TMS320F2812 in the described DSP control module 307 is 3.3V level (figure does not show); So the low level signal of optical coupling isolation circuit 306 outputs needs through receiving the PDPINTA pin of TMS320F2812 after the level transferring chip 74LVC4245 conversion; This PDPINTA pin interrupts to the TMS320F2812 application when low level, and when low level, a plurality of PWM output pin PWM1 of TMS320F2812, PWM2......PWMn (as shown in Figure 4) can be changed to high-impedance state simultaneously; Thereby directly block pwm pulse, promptly all PWM output pins all are high-impedance state.The output that a plurality of PWM output pins of described dsp chip are described DSP control modules.
Because a plurality of PWM output pins (as shown in Figure 4) of described DSP control module 307 link to each other with the input pin of described switching tube driver module 308; So when the PWM output pin was high-impedance state, the output pin of switching tube driver module 308 also was high-impedance state.
And then; Because the grid of six IGBT switching tubes in the output pin of described switching tube driver module 308 and the described high-power photovoltaic DC-to-AC converter 300---first switch transistor T 1, second switch pipe T2, the 3rd switch transistor T 3, the 4th switch transistor T 4, the 5th switch transistor T 5, the 6th switch transistor T 6 links to each other respectively; So; Just six IGBT switching tubes in the high-power photovoltaic DC-to-AC converter 300 of conducting end subsequently---and promptly first switch transistor T 1, second switch pipe T2, the 3rd switch transistor T 3, the 4th switch transistor T 4, the 5th switch transistor T 5, the 6th switch transistor T 6 are ended; Make circuit get into the afterflow state; Thereby play the short-circuit protection effect; Thereby force electric current to descend, and then protect six IGBT switching tubes---first switch transistor T 1, second switch pipe T2, the 3rd switch transistor T 3, the 4th switch transistor T 4, the 5th switch transistor T 5, the 6th switch transistor T 6 are not damaged.
Wherein, Described afterflow state refers to; When six IGBT switching tubes in the high-power photovoltaic DC-to-AC converter 300---after first switch transistor T 1, second switch pipe T2, the 3rd switch transistor T 3, the 4th switch transistor T 4, the 5th switch transistor T 5, the 6th switch transistor T 6 are ended; Short circuit current can---be that short circuit current is through described six diodes---through fly-wheel diode repid discharge as shown in Figure 4 the 101 diode D101, the 102 diode D102, the 103 diode D103, the 104 diode D104, the 105 diode D105, the 106 diode D106 repid discharge, thus electric current is descended fast.
In sum, this programme has following characteristics with respect to the technical scheme of prior art:
1. utilize the Hall current sensor that response speed is fast, certainty of measurement is high that inverter output transient current value is sampled:
The described high-power photovoltaic DC-to-AC converter fast short-circuit protective circuit of the utility model; Its current sampling data is respectively A, B, C three-phase alternating current side transient current value; In order to guarantee that response speed is fast and certainty of measurement is high; Current sampling device is to adopt a plurality of Hall current sensors---the first Hall current sensor IT1, the second Hall current sensor IT2, the 3rd Hall current sensor IT3 realize that the current transformer sample rate current of prior art is judged the mode of blocking inverter bridge through transformation ratio more relatively; Has higher sensitivity, quicker response.
2. protective circuit all is made up of conventional hardware circuit, and good reliability, cost are low:
The described circuit of the utility model, the realization of its defencive function are realized by conventional hardware circuit that fully it is formed components and parts and is common component; Quick action, security reliability is good, compares with using general integrated current protection module; The utility model has been simplified design cycle; Having reduced design cost, had better economy, is a kind of short-circuit protection circuit of practicality.
3. protection speed fast (directly stopping the ripple of sending out of PWM):
The described circuit of the utility model, its short-circuit protection are to realize protecting through the PWM output pin that blocks control chip, are not to realize through the PWM output pin of lockout switch pipe driver module.
Because; If realize through the PWM output pin of lockout switch pipe driver module 308; Just needing to drive earlier switching tube driver module 308 inner corresponding processing procedures and just can turn-off six IGBT switching tubes---first switch transistor T 1, second switch pipe T2, the 3rd switch transistor T 3, the 4th switch transistor T 4, the 5th switch transistor T 5, the 6th switch transistor T 6 have certain operating lag.
So the described short-circuit protection circuit of the utility model is to realize protecting through the PWM output pin that blocks control chip, its protection speed faster (directly stopping the ripple of sending out of PWM).
4, can both use dissimilar short troubles:
The described short-circuit protection circuit of the utility model; Be to realize protecting through the PWM output pin that blocks control chip; No matter to load short circuits still is the straight-through short circuit that causes of IGBT upper and lower bridge arm; Can both suppress the growth of electric current in the circuit fast, well protect the IGBT switching tube to cause overtemperature to damage because of electric current is excessive.
5. all can adopt to different capacity grade photovoltaic DC-to-AC converter, highly versatile, flexible design:
As shown in Figure 4; The described circuit versatility of the utility model is stronger; Photovoltaic DC-to-AC converter to different capacity;---resistance of the resistance and the reference voltage divider resistance of first resistance R the 1, the 11 resistance R 11, the 21 resistance R 21---the 43 resistance R 43, the 44 resistance R 44, the 45 resistance R 45---can realize short-circuit protection function only need to revise sampling resistor.
6. detection speed is fast:
The utlity model has current threshold testing circuit 305, therefore have the fast characteristics of detection speed.
7. adopted the Filtering Processing of guard signal, avoided because the mistake that the spike burr causes is protected, reliability is high:
As shown in Figure 4, the maximum value signal before the tenth resistance R 10 in the current threshold testing circuit 305,9 pairs of input voltage comparators of the 9th capacitor C---the 5th amplifier U5 carries out filtering, filtering spike burr, the false alarm of avoiding the spike burr to cause.
The more than just preferred embodiment of the utility model of explanation, just illustrative as far as the utility model, and nonrestrictive; Those of ordinary skills understand, under the situation that does not break away from spirit that the utility model accompanying claims limited and scope, through analysis, reasoning or limited experiment; Can make many modifications, change, or equivalence; Obtain a plurality of technical schemes, but these technical schemes will fall in the protection range of the utility model all.
Claims (7)
1. the short-circuit protection circuit of a high-power photovoltaic DC-to-AC converter; It is characterized in that; It comprises high-power photovoltaic DC-to-AC converter, alternating current sample circuit, signal conditioning circuit, asks absolute value and maximum value circuit, and reference voltage produces circuit, current threshold testing circuit; Optical coupling isolation circuit reaches DSP control module, switching tube driver module;
Wherein, described high-power photovoltaic DC-to-AC converter comprises a plurality of IGBT switching tubes;
The A of described high-power photovoltaic DC-to-AC converter, B, C three-phase output end are electrical connected with A, B, the C three-phase input end of described alternating current sample circuit respectively;
The A of described alternating current sample circuit, B, C three-phase output end are electrical connected with A, B, the C three-phase input end of described signal conditioning circuit respectively;
The A of described signal conditioning circuit, B, C three-phase output end are electrical connected with described A, B, the C three-phase input end of absolute value and maximum value circuit asked respectively;
Described reference voltage produces the output of circuit and second input of described current threshold testing circuit is electrical connected;
The described output of absolute value and maximum value circuit and the first input end of described current threshold testing circuit asked is electrical connected;
The output of described current threshold testing circuit and described optical coupling isolation circuit input are electrical connected;
The input of described optical coupling isolation circuit output and described DSP control module is electrical connected;
A plurality of PWM output pins of described DSP control module link to each other with the input pin of described switching tube driver module;
The grid of a plurality of IGBT switching tubes in the output pin of described switching tube driver module and the described high-power photovoltaic DC-to-AC converter links to each other respectively.
2. the short-circuit protection circuit of high-power photovoltaic DC-to-AC converter as claimed in claim 1 is characterized in that, described alternating current sample circuit comprises a plurality of AC side Hall current sensors, a plurality of sampling resistor, a plurality of resistance, a plurality of electric capacity; Wherein, described a plurality of AC side Hall current sensor comprises first Hall current sensor, second Hall current sensor, the 3rd Hall current sensor; Described a plurality of sampling resistor comprises first resistance, the 11 resistance, the 21 resistance; Described a plurality of resistance comprises second resistance R 2, the 12 resistance, the 22 resistance, and described a plurality of electric capacity comprise first capacitor C 1, the 11 electric capacity, the 21 electric capacity;
Wherein, first end of first Hall current sensor is the A phase input of alternating current sample circuit; Second end of first Hall current sensor links to each other with first end of first end of first resistance and second resistance; The second end ground connection of first resistance; The second end ground connection of first electric capacity; Second end of second resistance links to each other the back as the A phase output terminal of alternating current sample circuit with first end of first electric capacity;
First end of second Hall current sensor is the B phase input of alternating current sample circuit; Second end of second Hall current sensor links to each other with first end of the 11 resistance and first end of the 12 resistance; The second end ground connection of the 11 resistance; The second end ground connection of the 11 electric capacity; Second end of the 12 resistance links to each other the back as the B phase output terminal of alternating current sample circuit with first end of the 11 electric capacity;
First end of the 3rd Hall current sensor is the C phase input of alternating current sample circuit; Second end of the 3rd Hall current sensor links to each other with first end of the 21 resistance and first end of the 22 resistance; The second end ground connection of the 21 resistance; The second end ground connection of the 21 electric capacity; Second end of the 22 resistance links to each other the back as the C phase output terminal of alternating current sample circuit with first end of the 21 electric capacity.
3. the short-circuit protection circuit of high-power photovoltaic DC-to-AC converter as claimed in claim 1 is characterized in that, comprises A phase computing amplifying return circuit in the described signal conditioning circuit, B phase computing amplifying return circuit, C phase computing amplifying return circuit and a plurality of voltage follower; Wherein, voltage follower comprises second amplifier, the 12 amplifier, the 22 amplifier; A phase computing amplifying return circuit comprises first amplifier, the 3rd resistance, the 4th resistance; B phase computing amplifying return circuit comprises the 11 amplifier, the 13 resistance, the 14 resistance, and C phase computing amplifying return circuit comprises the 21 amplifier, the 23 resistance, the 24 resistance;
Wherein, first amplifier, the 11 amplifier, the 21 amplifier and second amplifier, the 12 amplifier, the 22 amplifier are LM258;
The in-phase end of first amplifier is the A phase input of signal conditioning circuit; First end of the 3rd resistance links to each other with first end of the end of oppisite phase of first amplifier and the 4th resistance; The second end ground connection of the 3rd resistance; Second end of the 4th resistance links to each other with the in-phase end of the output of first amplifier and second amplifier; The second end ground connection of the 5th resistance; The end of oppisite phase of second amplifier links to each other with the output of second amplifier and first end of the 5th resistance, and as the A phase output terminal of signal conditioning circuit;
The in-phase end of the 11 amplifier is the B phase input of signal conditioning circuit; First end of the 13 resistance links to each other with the end of oppisite phase of the 11 amplifier and first end of the 14 resistance; The second end ground connection of the 13 resistance; Second end of the 14 resistance links to each other with the output of the 11 amplifier and the in-phase end of the 12 amplifier; The second end ground connection of the 15 resistance; The end of oppisite phase of the 12 amplifier links to each other with first end of the output of the 12 amplifier and the 15 resistance, and as the B phase output terminal of signal conditioning circuit;
The in-phase end of the 21 amplifier is the C phase input of signal conditioning circuit; First end of the 23 resistance links to each other with the end of oppisite phase of the 21 amplifier and first end of the 24 resistance; The second end ground connection of the 23 resistance; Second end of the 24 resistance links to each other with the output of the 21 amplifier and the in-phase end of the 22 amplifier; The second end ground connection of the 25 resistance; The end of oppisite phase of the 22 amplifier links to each other with first end of the output of the 22 amplifier and the 25 resistance, and as the C phase output terminal of signal conditioning circuit.
4. the short-circuit protection circuit of high-power photovoltaic DC-to-AC converter as claimed in claim 1; It is characterized in that described reference voltage produces circuit and comprises a plurality of reference voltage divider resistances, reference voltage chip and an operational amplifier---the 41 amplifier; Wherein, described reference voltage chip is LM236AZ5; Described a plurality of reference voltage divider resistance comprises the 43 resistance, the 44 resistance;
The first pin ground connection of reference voltage chip; The 3rd pin open circuit of reference voltage chip; Second pin of reference voltage chip links to each other with first end of first end of the 39 resistance, the 7th electric capacity and first end of the 40 resistance; Second end of the 39 resistance links to each other with+15 voltage sources; The second end ground connection of the 7th electric capacity; The in-phase end of the 41 amplifier links to each other with second end of the 40 resistance; The end of oppisite phase of the 41 amplifier links to each other with first end of second end of the 41 resistance and the 42 resistance; The first end ground connection of the 41 resistance; The output of the 41 amplifier links to each other with first end of second end of the 42 resistance and the 43 resistance; The second end ground connection of the 44 resistance; Second end of the 43 resistance links to each other with first end of the 44 resistance, produces the output of circuit as reference voltage.
5. the short-circuit protection circuit of high-power photovoltaic DC-to-AC converter as claimed in claim 1; It is characterized in that; Described current threshold testing circuit comprises a voltage comparator---the 5th amplifier, a plurality of resistance and an electric capacity---the 9th electric capacity; Wherein, voltage comparator---the 5th amplifier is comparator LM2903; Described a plurality of resistance does---the tenth resistance, the 45 resistance;
The tenth resistance first end is the first input end of current threshold testing circuit; Second end of the tenth resistance links to each other with the end of oppisite phase of first end of the 9th electric capacity and the 5th amplifier; The second end ground connection of the 9th electric capacity; First end of the 45 resistance is second input of current threshold testing circuit; First end of the 45 resistance links to each other with the output of the 5th amplifier, as the output of current threshold testing circuit.
6. the short-circuit protection circuit of high-power photovoltaic DC-to-AC converter as claimed in claim 1 is characterized in that, described optical coupling isolation circuit can comprise rapid light coupling chip, the 3rd diode, the 4th diode and the 46 resistance; Wherein, described rapid light coupling chip is TLP559;
The input of optical coupling isolation circuit is the negative pole of the 3rd diode; The output of current threshold testing circuit links to each other with the negative pole of the 3rd diode; The positive pole of the 3rd diode links to each other with the former limit light-emitting diode negative pole end of rapid light coupling chip and the positive pole of the 4th diode; Former limit light-emitting diode positive terminal and the negative pole of the 4th diode and first end of the 46 resistance of rapid light coupling chip links to each other; Second end of the 46 resistance links to each other with+15V power supply; The grounded emitter of the secondary phototriode of rapid light coupling chip; Second end of the 47 resistance links to each other with+5V power supply; The collector electrode of the secondary phototriode of rapid light coupling chip links to each other with first end of the 46 resistance, as the output of optical coupling isolation circuit.
7. the short-circuit protection circuit of high-power photovoltaic DC-to-AC converter as claimed in claim 1 is characterized in that, described DSP control module comprises level transferring chip and dsp chip;
Wherein, level transferring chip is 74LVC4245, and dsp chip is TMS320F2812;
First end of level transferring chip is the input of DSP control module; Second end of level transferring chip links to each other with the PDPINTA pin of dsp chip;
The output that a plurality of PWM output pins of described dsp chip are described DSP control modules.
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| CN2012201266422U CN202535041U (en) | 2012-03-29 | 2012-03-29 | Short-circuit protecting circuit of high-power photovoltaic inverter |
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| CN2012201266422U CN202535041U (en) | 2012-03-29 | 2012-03-29 | Short-circuit protecting circuit of high-power photovoltaic inverter |
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Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103022976A (en) * | 2012-12-13 | 2013-04-03 | 广州三晶电气有限公司 | Frequency converter output short circuit protection circuit and protection method |
| CN103066819A (en) * | 2012-12-03 | 2013-04-24 | 深圳市汇川技术股份有限公司 | Insulated gate bipolar transistor (IGBT) over-current protection circuit |
| CN103715662A (en) * | 2014-01-09 | 2014-04-09 | 惠州天能源科技有限公司 | Short circuit and overload protection circuit of photovoltaic energy storage inverse control all-in-one machine |
| CN103986347A (en) * | 2014-05-12 | 2014-08-13 | 东南大学 | Three-phase bridge-type half-control rectification trigger circuit with protection function |
| CN104950207A (en) * | 2014-03-25 | 2015-09-30 | 艾默生网络能源有限公司 | Short circuit detecting method and device for photovoltaic inverter |
| CN105048856A (en) * | 2015-06-17 | 2015-11-11 | 中国石油大学(北京) | Sine pulse crude oil electric dehydration power supply based on PWM and generation method thereof |
| CN107069667A (en) * | 2016-12-28 | 2017-08-18 | 株洲中车时代电气股份有限公司 | A kind of IGBT protection circuit for possessing AF panel |
| CN107492868A (en) * | 2017-10-13 | 2017-12-19 | 陕西科技大学 | Three-phase inverter Over Current Protection System and method |
| CN107748501A (en) * | 2017-11-22 | 2018-03-02 | 国网湖南节能服务有限公司 | A kind of wisdom home energy source central controller and its control method |
| CN109599843A (en) * | 2019-01-09 | 2019-04-09 | 深圳市德兰明海科技有限公司 | A kind of current foldback circuit and inverter of light-coupled isolation |
| CN110535100A (en) * | 2019-10-14 | 2019-12-03 | 江苏为恒智能科技有限公司 | Protection circuit of inverter based on BUS voltage stepping |
| CN110729705A (en) * | 2019-09-09 | 2020-01-24 | 中国南方电网有限责任公司超高压输电公司昆明局 | Short-circuit protection method for direct-current transmission converter valve |
| CN110794328A (en) * | 2019-10-30 | 2020-02-14 | 汉中一零一航空电子设备有限公司 | Detection circuit and detection method for detecting overload or short-circuit fault |
| CN111725788A (en) * | 2020-05-22 | 2020-09-29 | 深圳供电局有限公司 | Overcurrent protection device of energy storage converter |
| CN112649661A (en) * | 2020-12-30 | 2021-04-13 | 无锡市同飞科技有限公司 | Current detection circuit based on Hall sensor |
| CN112910221A (en) * | 2021-02-01 | 2021-06-04 | 西北工业大学 | Dual-redundancy hidden power supply system suitable for electrochromic glass |
-
2012
- 2012-03-29 CN CN2012201266422U patent/CN202535041U/en not_active Expired - Fee Related
Cited By (26)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103066819A (en) * | 2012-12-03 | 2013-04-24 | 深圳市汇川技术股份有限公司 | Insulated gate bipolar transistor (IGBT) over-current protection circuit |
| CN103022976B (en) * | 2012-12-13 | 2015-10-28 | 广州三晶电气有限公司 | A kind of frequency converter output short circuit protection circuit and guard method |
| CN103022976A (en) * | 2012-12-13 | 2013-04-03 | 广州三晶电气有限公司 | Frequency converter output short circuit protection circuit and protection method |
| CN103715662A (en) * | 2014-01-09 | 2014-04-09 | 惠州天能源科技有限公司 | Short circuit and overload protection circuit of photovoltaic energy storage inverse control all-in-one machine |
| CN104950207B (en) * | 2014-03-25 | 2017-08-29 | 艾默生网络能源有限公司 | The method for detecting short circuit and device of a kind of photovoltaic DC-to-AC converter |
| CN104950207A (en) * | 2014-03-25 | 2015-09-30 | 艾默生网络能源有限公司 | Short circuit detecting method and device for photovoltaic inverter |
| CN103986347A (en) * | 2014-05-12 | 2014-08-13 | 东南大学 | Three-phase bridge-type half-control rectification trigger circuit with protection function |
| CN103986347B (en) * | 2014-05-12 | 2016-09-14 | 东南大学 | A kind of three-phase semi-controlled bridge type rectification triggering circuit with defencive function |
| CN105048856B (en) * | 2015-06-17 | 2018-09-21 | 中国石油大学(北京) | A kind of sinusoidal impulse crude oil electric dewatering power supply and its production method based on PWM |
| CN105048856A (en) * | 2015-06-17 | 2015-11-11 | 中国石油大学(北京) | Sine pulse crude oil electric dehydration power supply based on PWM and generation method thereof |
| CN107069667A (en) * | 2016-12-28 | 2017-08-18 | 株洲中车时代电气股份有限公司 | A kind of IGBT protection circuit for possessing AF panel |
| CN107492868A (en) * | 2017-10-13 | 2017-12-19 | 陕西科技大学 | Three-phase inverter Over Current Protection System and method |
| CN107492868B (en) * | 2017-10-13 | 2019-09-17 | 陕西科技大学 | Three-phase inverter Over Current Protection System and method |
| CN107748501A (en) * | 2017-11-22 | 2018-03-02 | 国网湖南节能服务有限公司 | A kind of wisdom home energy source central controller and its control method |
| CN109599843A (en) * | 2019-01-09 | 2019-04-09 | 深圳市德兰明海科技有限公司 | A kind of current foldback circuit and inverter of light-coupled isolation |
| CN109599843B (en) * | 2019-01-09 | 2024-09-10 | 深圳市德兰明海新能源股份有限公司 | Over-current protection circuit and inverter isolated by optical coupler |
| CN110729705B (en) * | 2019-09-09 | 2021-06-25 | 中国南方电网有限责任公司超高压输电公司昆明局 | Short-circuit protection method for direct-current transmission converter valve |
| CN110729705A (en) * | 2019-09-09 | 2020-01-24 | 中国南方电网有限责任公司超高压输电公司昆明局 | Short-circuit protection method for direct-current transmission converter valve |
| CN110535100A (en) * | 2019-10-14 | 2019-12-03 | 江苏为恒智能科技有限公司 | Protection circuit of inverter based on BUS voltage stepping |
| CN110794328A (en) * | 2019-10-30 | 2020-02-14 | 汉中一零一航空电子设备有限公司 | Detection circuit and detection method for detecting overload or short-circuit fault |
| CN111725788A (en) * | 2020-05-22 | 2020-09-29 | 深圳供电局有限公司 | Overcurrent protection device of energy storage converter |
| CN111725788B (en) * | 2020-05-22 | 2023-01-24 | 深圳供电局有限公司 | Overcurrent protection device of energy storage converter |
| CN112649661A (en) * | 2020-12-30 | 2021-04-13 | 无锡市同飞科技有限公司 | Current detection circuit based on Hall sensor |
| CN112649661B (en) * | 2020-12-30 | 2023-09-26 | 无锡市同飞科技有限公司 | Current detection circuit based on Hall sensor |
| CN112910221A (en) * | 2021-02-01 | 2021-06-04 | 西北工业大学 | Dual-redundancy hidden power supply system suitable for electrochromic glass |
| CN112910221B (en) * | 2021-02-01 | 2024-02-02 | 西北工业大学 | Dual-redundancy hidden power supply system suitable for electrochromic glass |
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