CN105958436A - Capacitor failure protection circuit - Google Patents
Capacitor failure protection circuit Download PDFInfo
- Publication number
- CN105958436A CN105958436A CN201610490063.9A CN201610490063A CN105958436A CN 105958436 A CN105958436 A CN 105958436A CN 201610490063 A CN201610490063 A CN 201610490063A CN 105958436 A CN105958436 A CN 105958436A
- Authority
- CN
- China
- Prior art keywords
- generation system
- circuit
- reference voltage
- protection
- bus
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/20—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess voltage
- H02H3/202—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to excess voltage for dc systems
-
- 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
- H02H7/16—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 capacitors
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Inverter Devices (AREA)
Abstract
The invention relates to a capacitor failure protection circuit applied to a power generation system. The power generation system comprises a DC source and a semiconductor inverter which are connected through DC buses, wherein the other end of the inverter is connected with an AC side; two or more capacitors with buffer and filter functions are connected between the DC buses in series; the protection circuit comprises a sampling circuit, a comparator and a reference voltage module; the sampling circuit is connected with series connection points of the DC buses and the series capacitors and carries out voltage sampling; the comparator is connected with the sampling circuit and the reference voltage module separately, carries out protection judgment through judging whether sampling voltage collected by the sampling circuit exceeds a reference voltage range set in the reference voltage module or not, and triggers a protection function if the sampling voltage collected by the sampling circuit exceeds the reference voltage range set in the reference voltage module. When the capacitor failure protection circuit is used, on one hand, a front-stage DC side power supply circuit and a post-stage AC side power supply circuit are cut off, and on the other hand, electric energy in a DC side and an AC side in the power generation system is discharged, so that the electric energy in the DC side and the AC side in the power generation system is prevented from being injected into the remaining capacitors.
Description
Technical field
The present invention relates to a kind of protection circuit, the protection circuit of a kind of capacitive faults, particularly suitable
In grid-connected power generation system.
Background technology
Along with the efficiency of grid-connected power generation system requires little by little to improve, the efficiency to grid-connected power generation system
The semiconductor power converter of vital core component and system line loss propose higher wanting
Ask.And reduce electric current in circuit, it is one of the measure of most effective improving energy efficiency.Then generation of electricity by new energy system
DC bus-bar voltage in system is the most gradually raised, and is lifted to 1000V from 600V, is even improved
1500V, to reduce input current further, reduces line loss, promotes system effectiveness.
Fig. 1 show typical grid-connected power generation system circuit block diagram, mainly by grid-connected power generation system
DC source, electrochemical capacitor CE1 and CE2, and semiconductor inverter three part composition, wherein new forms of energy are sent out
The DC source of electricity system is required for jumbo dc bus electrochemical capacitor with follow-up semiconductor inverter
Buffer and filter.The highest pressure for 500V due to electrolysis condenser, for meeting constantly raise defeated
Entering the requirement of voltage, usual employing can be connected, in Fig. 1 by least 2 500V electrochemical capacitors
Shown in CE1 and CE2, be respectively connecting to after CE1 and CE2 series connection dc bus (+) anode and direct current be female
Line (-) negative terminal, then level is coupled to semiconductor inverter, generates electricity connecting AC.
For meeting 1500V input voltage or the requirement of higher input voltage, it is necessary to multiple 500V
Electrolysis condenser is connected, such as 3,4 series connection or more series connection, as in figure 2 it is shown,
By bridging after the series connection of many electrochemical capacitors of electrochemical capacitor CE1, CE2 ... and CEn and dc bus (+)
Anode and dc bus (-) between negative terminal.
It addition, the semiconductor inverter in Fig. 1 and Fig. 2 can be single-phase inverter, it is also possible to be three
Phase inverter.
Below first as a example by the grid-connected power generation system circuit of 2 electrochemical capacitors concatenation typical shown in Fig. 1,
Illustrate safety failure and life safety problem that current grid-connected power generation system exists.
Broke down, when short circuit phenomenon occurs, as shown in Figure 3 when the electrochemical capacitor CE1 in Fig. 1 loses efficacy.
DC bus-bar voltage will the most all add to CE2, DC side and all of electricity of AC in simultaneity factor
All can gather to electrochemical capacitor CE2, electrochemical capacitor CE2 individually undertake, so can be at least
Cause electrochemical capacitor CE2 over-voltage breakdown to burst, even smolder and phenomenon on fire, cause safety failure and people
Body safety.But, such safety failure is but not enough to trigger electrochemical capacitor prime DC source and partly lead
The protective measure action that body inverter rear class AC is conventional, cuts off unidirectional current source and inverter ac side
Electric energy pour into normal electrolysis condenser CE2.
When CE2 breaks down, and short circuit phenomenon occurs, as shown in Figure 4, also it is same case, direct current
Busbar voltage will the most all add to CE1, and in simultaneity factor, DC side and all of electric energy of AC are complete
Portion can gather to electrochemical capacitor CE1, electrochemical capacitor CE1 individually undertake, and so can at least cause
Electrochemical capacitor CE1 over-voltage breakdown bursts, and even smolders and phenomenon on fire, causes safety failure and person peace
Entirely.But, such safety failure is also not enough to trigger electrochemical capacitor prime DC source and quasiconductor is inverse
Become the protective measure action that device rear class AC is conventional, cut off unidirectional current source and the electricity of inverter ac side
Electrolysis condenser CE1 can be poured into.
Also have another kind of situation that the over-voltage breakdown of electrochemical capacitor also can be caused to burst, ultimately result in and smolder and rise
Fire phenomenon.When electrochemical capacitor CE1 and CE2 elapses over time, and electrolyte can constantly volatilize, and causes
The capacitance of electrochemical capacitor reduces, but CE1 and CE2 capacity minimizing degree is the most different, even if adopting
With equalizer circuit, but after electrochemical capacitor volume change is beyond the limit of power of equalizer circuit, also can cause CE1
Big with the voltage difference mutation that CE2 undertakes, rated voltage 500V that one of them electrolysis condenser exceeds,
The over-voltage breakdown causing relevant electrochemical capacitor bursts phenomenon, also results in and smolders and phenomenon on fire, causes peace
Total failure and personal safety.Same such safety failure is also not enough to trigger conventional protective measure action,
The electric energy cutting off direct current input side and inverter ac side pours into the electrolysis condenser not lost efficacy.
Summary of the invention
It is an object of the invention to provide the protection circuit of a kind of capacitive faults, be mainly used in solving generating system
The safety problem that in system circuit, the failure of removal of the electric capacity of DC side causes, during use, it can give prime
The DC source of electricity generation system and rear class semiconductor inverter send triggering signal and implement electrochemical capacitor protection
Function；When one of them electrochemical capacitor in series capacitance lost efficacy, the direct current on the one hand cutting off prime supplies
The AC supply access of electric pathway and rear class, DC side and AC in electricity generation system of on the other hand releasing
In electric energy, it is to avoid in electricity generation system, the electric energy of DC side and AC pours into remaining electric capacity, occurs
Pressure punctures the phenomenon burst, to realize the protection to remaining electric capacity, it is to avoid more serious safety event occurs
Barrier and human safety issues.
For achieving the above object, the present invention is realized in.
The protection circuit of a kind of capacitive faults, in electricity generation system, described electricity generation system includes passing through
Dc bus connects DC source, semiconductor inverter, and the inverter other end connects AC；Dc bus
Between be in series with more than 2 or 2 there is buffering and the electric capacity of filter function；It is characterized in that: described
Protection circuit includes sample circuit, comparator and reference voltage module；Wherein:
Described sample circuit is attached with the point that concatenates of dc bus and series capacitance, and carries out electricity
Pressure sampling；
Described comparator connects sample circuit and reference voltage module respectively, by judging that sample circuit is adopted
Whether the sampled voltage of collection exceedes the reference voltage range arranged in reference voltage module is done protection judgement,
The most then trigger protection function.
The protection circuit of described capacitive faults, it is characterised in that: described defencive function include by than
The protection that relatively device sends triggers the supply access of the DC source of signal cut prime and the confession of the AC of rear class
Electric pathway.
The protection circuit of described capacitive faults, it is characterised in that: described defencive function include by than
The protection that relatively device sends triggers signal and controls bridging and the transistor of dc bus in rear class semiconductor inverter
The conducting of brachium pontis, the electric energy in DC side and AC in electricity generation system of releasing, it is to avoid in electricity generation system
The electric energy of DC side and AC pours into remaining electric capacity.
The protection circuit of described capacitive faults, it is characterised in that: described semiconductor inverter is single-phase
Inverter or three-phase inverter.
Capacitive faults protection circuit in the electricity generation system that the present invention proposes, can solve the protection circuit of routine
Cannot the defect of identification capacitive faults with device, it is ensured that electricity generation system safe operation；The protection simultaneously increased
The simple and reliable easy realization of circuit, is the solution that a kind of cost performance is high.
Accompanying drawing explanation
Fig. 1 is existing grid-connected power generation system circuit block diagram.
Fig. 2 is the grid-connected power generation system circuit block diagram of existing multiple electrolysis condenser concatenation.
Fig. 3 is the grid-connected power generation system circuit block diagram under CE1 failure of removal short circuit.
Fig. 4 is the grid-connected power generation system circuit block diagram under CE2 failure of removal short circuit.
Fig. 5 is that protection circuit of the present invention is applied to grid-connected power generation system circuit block diagram.
Fig. 6 is the internal circuit block diagram of protection circuit in the present invention.
Fig. 7 is the structural representation of the embodiment of the present invention 1.
Fig. 8 is the structural representation of the embodiment of the present invention 2.
Fig. 9 is the structural representation of the embodiment of the present invention 3.
Figure 10 is the structural representation of the embodiment of the present invention 4.
In figure: A: the DC source of grid-connected power generation system；M: dc bus (+)；N: dc bus (-)；
C: semiconductor inverter (single-phase or three-phase inverter)；B: AC；1: protection circuit；11: touch
Signal；21: electrochemical capacitor CE1；22: electrochemical capacitor CE2；23: electrochemical capacitor CEn-1；
24: electrochemical capacitor CEn；31: reference voltage Vref；32: comparator；33: sample circuit；34:
Protection circuit；51: semiconductor inverter；52: drive circuit；53: panel；61: transistor
Q1；62: transistor Q2；63: transistor Q3；64: transistor Q4；65: inductance L1；66:
Electric capacity C1；71: brachium pontis A；72: brachium pontis B；73: brachium pontis C；81: transistor Qa1；82:
Transistor Qb1；83: transistor Qc1；84: transistor Qa2；85: transistor Qb2；86:
Transistor Qc2；91: inductance La；92: inductance Lb；93: inductance Lc；94: electric capacity Ca；95:
Electric capacity Cb；96: electric capacity Cc.
Detailed description of the invention
The invention discloses the protection circuit of a kind of DC generation side electrochemical capacitor fault, as shown in Figure 5:
This protection circuit is by detecting the junction point voltage V of each series connection electrolysis electric capacity of DC bus-bar voltage Vinc1、
Vc2、Vcn-1And Vcn, scope is set with the protection point in protection circuit and compares, to prime new forms of energy
The DC source of electricity generation system and rear class semiconductor inverter send triggering signal and implement electrochemical capacitor protection
Function；When one of them electrochemical capacitor in series connection electrolysis electric capacity lost efficacy, each junction point voltage can exceed
The protection domain arranged in protection circuit, protection circuit will be to the DC source of prime grid-connected power generation system
Export " triggering signal " with rear class semiconductor inverter, on the one hand cut off prime direct current supply path and
The AC supply access of rear class, controls bridging and direct current in rear class semiconductor inverter the most simultaneously
The conducting of the transistor brachium pontis of bus, in electricity generation system of releasing, the electric energy in DC side and AC, keeps away
Exempt from the electric energy of DC side and AC in electricity generation system and pour into remaining electrochemical capacitor, occur over-voltage breakdown to explode
The phenomenon split, to realize protection to remaining electrochemical capacitor, it is to avoid occur more serious safety failure and
Human safety issues.Semiconductor inverter shown in Fig. 5 can be single-phase inverter, it is also possible to for three-phase
Inverter.
For solving grid-connected power generation system bridges the safety that the electrochemical capacitor failure of removal of dc bus causes
Problem, the present invention proposes the protection circuit of a kind of dc bus electrochemical capacitor failure of removal, sends out with new forms of energy
The concrete connected mode of electricity system as it is shown in fig. 7, wherein protection circuit one end and dc bus (+) voltage
“Vin" and the junction point V of each electrochemical capacitorc2、……Vcn-1And VcnBe connected, the other end respectively with prime
The DC source of grid-connected power generation system and the semiconductor inverter of rear class in panel or the driving of transistor
Dynamic device is connected.
The present invention propose protection circuit by sampling dc bus (+) voltage " Vin" and multiple series electrical
Solve junction point voltage V corresponding between electric capacity CE1, CE2 ... CEn-1 and CEnc2、……Vcn-1
And Vcn, through the comparator within protection circuit, the protection domain that arrange internal with protection circuit compares
Judging, after each junction point voltage is beyond the protection domain arranged, protection circuit will be sent out to prime direct current
The DC source of electricity system and rear class semiconductor inverter output " triggering signal ", on the one hand cut off DC side
Direct current supply path and AC supply access, on the other hand control in rear class semiconductor inverter the most simultaneously
The conducting of transistor brachium pontis between bridging and dc bus, with DC side in grid-connected power generation system of releasing and
The dump energy of AC, it is to avoid in electricity generation system, the dump energy of DC side and AC pours into remaining
Electrochemical capacitor, the phenomenon occurring over-voltage breakdown to burst, cause safety failure and personal safety, right to realize
Remaining electrochemical capacitor is protected, it is to avoid more serious safety failure and human safety issues occur.
Fig. 6 is the internal circuit block diagram of protection circuit, including voltage sampling circuit, reference voltage Vref
With comparator three part.The present invention propose protection circuit by sampling dc bus (+) voltage " Vin”
Junction point voltage V each with electrochemical capacitorc2、……Vcn-1And VcnAfter, connect respectively after sampled processing of circuit
It is connected to comparator, then by comparator and reference voltage VrefThe protection domain arranged compares judgement,
When the protection domain that the sampled voltage of each junction point is arranged beyond protection circuit, comparator will export and " touch
Signal " to the DC source of prime DC power generation system of prime and rear class semiconductor inverter, on the one hand
Cut off direct current supply path and the AC supply access of DC side, control rear class the most simultaneously and partly lead
The conducting of the transistor brachium pontis of bridging and dc bus in body inverter, with DC side in electricity generation system of releasing
Dump energy with AC, it is to avoid in electricity generation system, the dump energy of DC side and AC pours into remaining
Electrochemical capacitor, there is the phenomenon that bursts of over-voltage breakdown, to realize remaining electrochemical capacitor is protected,
Avoid more serious safety failure and human safety issues.
The wherein reference voltage V in Fig. 6refArrange protection domain for from central value be VrefChange in voltage
Scope, such as from 50%VrefTo 150%VrefExcursion.
The wherein reference voltage V in Fig. 6refCan be fixing reference voltage, it is also possible to for Vin/ n, Vin
For DC bus-bar voltage, " n " is number n of bridging and the series connection electrolysis electric capacity of dc bus.Work as benchmark
Voltage Vref=VinDuring/n, reference voltage VrefWill be along with DC bus-bar voltage VinChange and change,
Protection circuit so can be made to be more suitable for large-scale input voltage change application.
Wherein the point of the sampled voltage in Fig. 6 can need not to gather simultaneously dc bus (+) voltage VinWith
All each point voltage V of series connection electrolysis electric capacity junction pointc2、……Vcn-1And VcnEven if only including part
Sampled point can also realize same defencive function.
Wherein the comparator in Fig. 6 can realize multilevel iudge function by hardware, it is also possible to passes through software
Realize multilevel iudge function.
Embodiment 1
Fig. 7 is the block diagram of electrochemical capacitor fault secure circuit in a kind of single-phase new forms of energy DC power generation system band,
Including four parts: the DC source of grid-connected power generation system, electrochemical capacitor CE1 and CE2, quasiconductor
Inverter and protection circuit.After electrochemical capacitor CE1 and CE2 concatenation between bridging and dc bus, electrolysis
The positive pole of electric capacity CE1 connect dc bus (+), the negative pole of electrochemical capacitor CE2 connects positive pole and connects dc bus
(-)；The prime of electrochemical capacitor CE1 and CE2 connects the DC source of grid-connected power generation system, rear class order
Phase full-bridge inverter, then it is connected to AC electrical network by the wave filter of inductance L1 and electric capacity C1 composition
Live wire L and zero line N, or load；The positive pole of electrochemical capacitor CE1 and dc bus (+) junction point
Voltage " Vin", and the concatenation mid-point voltage V of electrochemical capacitor CE1 and CE2c2, it is respectively connecting to protection
Sample circuit in circuit, with reference voltage V after sampled processing of circuitrefThe protection domain arranged is carried out
Whether multilevel iudge goes beyond the scope；In protection circuit, the output of comparator is connected to the straight of grid-connected power generation system
Panel in stream source and semiconductor inverter or drive circuit, power back controlling DC source as required
Road and the cut-out of semiconductor inverter AC current supply circuit, and semiconductor inverter bridge arm transistor
Conducting.
In Fig. 7, semiconductor inverter is single-phase full-bridge inverter, by transistor Q1 and Q4, Q2 and
Q3 separately constitutes between 2 brachium pontis bridgings and dc bus.One be made up of transistor Q1 and Q4
Brachium pontis A, the midpoint of brachium pontis A is connected to electric capacity C1 and AC zero line N；By transistor Q2 and Q3
Another brachium pontis B of composition, after the midpoint of brachium pontis B is connected with inductance L1, through inductance L1 and electric capacity C1
AC live wire L it is connected to after connection.Transistor Q1, Q2, Q3 and Q4 by drive circuit according to control
The signal of plate or protection circuit controls being turned on and off of transistor.
When in Fig. 7 electrochemical capacitor CE1 and CE2 one of them break down inefficacy time, electrochemical capacitor connect
The voltage signal of some Vc1 can exceed reference voltage VrefProtection electricity after the protection domain arranged, in Fig. 7
Comparator in road will export to the DC source of prime DC power generation system and rear class single-phase full-bridge inverter
" triggering signal ", on the one hand cuts off direct current supply path and the AC supply access of DC side, another
Aspect controls bridging and one or 2 transistor bridges of dc bus in rear class single-phase full-bridge inverter simultaneously
The conducting of arm, with DC side in electricity generation system of releasing and the dump energy of AC, it is to avoid in electricity generation system
The dump energy of DC side and AC pours into remaining electrochemical capacitor, and the phenomenon that over-voltage breakdown bursts occurs,
To realize remaining electrochemical capacitor is protected, it is to avoid more serious safety failure and personal safety occur
Problem.
The wherein reference voltage V in Fig. 7refArrange protection domain for from central value be VrefChange in voltage
Scope, such as from 50%VrefTo 150%VrefExcursion.
The wherein reference voltage V in Fig. 7refCan be fixing reference voltage, it is also possible to for Vin/ 2, Vin
For DC bus-bar voltage.Work as reference voltage Vref=VinWhen/2, reference voltage VrefWill be along with dc bus
Voltage VinChange and change, so can make protection circuit be more suitable for large-scale input voltage change
Application.
Wherein the point of the sampled voltage in Fig. 7 can need not to gather simultaneously dc bus (+) voltage VinWith
The V of series connection electrolysis electric capacity junction pointC2Even if only including fractional-sample point voltage and can also realizing same guarantor
Protective function.
Wherein the comparator in Fig. 7 can realize multilevel iudge function by hardware, it is also possible to passes through software
Realize multilevel iudge function.
Embodiment 2
When the DC bus-bar voltage in new forms of energy DC power generation system is increased to use more than 2 electrolysis
Failure of removal inspection when capacitance series reaches dc bus insulation pressure requirement, to concatenation electrochemical capacitor
Survey particularly important, it is necessary to use special protection circuit to carry out failure of removal protection.
Fig. 8 is multiple electrochemical capacitor fault secure circuits in a kind of single-phase new forms of energy DC power generation system band
Block diagram, including four parts: the DC source of grid-connected power generation system, multiple electrochemical capacitor CE1,
CE2 ..., CEn-1 and CEn, semiconductor inverter and protection circuit.Electrochemical capacitor CE1, CE2 ...,
After CEn-1 and CEn concatenation between bridging and dc bus, the positive pole of electrochemical capacitor CE1 connects dc bus
(+), the negative pole of electrochemical capacitor CEn connect positive pole connect dc bus (-)；Electrochemical capacitor CE1 to CEn
The prime of composition electrochemical capacitor string connects the DC source of grid-connected power generation system, and rear class connects single-phase full-bridge inverter,
The wave filter consisted of inductance L1 and electric capacity C1 again is connected to the live wire L and zero line N of AC electrical network,
Or load；The positive pole of electrochemical capacitor CE1 and dc bus (+) junction point voltage Vin, electrochemical capacitor
The concatenation mid-point voltage Vc2 ... of CE1 and CE2, the concatenation midpoint of electrochemical capacitor CEn-2 and CEn-1
The sampling that the concatenation midpoint Vcn of Vcn-1 and electrochemical capacitor CEn-1 and CEn is respectively connected in protection circuit
Circuit, with reference voltage V after sampled processing of circuitrefThe protection domain arranged compares and judges whether
Go beyond the scope；In protection circuit, the output of comparator is connected to DC source and the quasiconductor of grid-connected power generation system
Panel in inverter or drive circuit, inverse to control DC source current supply circuit and quasiconductor as required
Become the cut-out of device AC current supply circuit, and the conducting of semiconductor inverter bridge arm transistor.
In Fig. 8, semiconductor inverter is single-phase full-bridge inverter, by transistor Q1 and Q4, Q2 and
Q3 separately constitutes between 2 brachium pontis bridgings and dc bus.One be made up of transistor Q1 and Q4
Brachium pontis A, the midpoint of brachium pontis A is connected to electric capacity C1 and AC zero line N；By transistor Q2 and Q3
Another brachium pontis B of composition, after the midpoint of brachium pontis B is connected with inductance L1, through inductance L1 and electric capacity C1
AC live wire L it is connected to after connection.Transistor Q1, Q2, Q3 and Q4 by drive circuit according to control
The signal of plate or protection circuit controls being turned on and off of transistor.
One of them electrochemical capacitor in the electrochemical capacitor string of electrochemical capacitor CE1 to CEn composition in Fig. 8
Device break down short-circuit failure time, the voltage signal of the junction point that electrochemical capacitor is corresponding can exceed reference voltage
VrefAfter the protection domain arranged, the comparator in protection circuit in Fig. 8 will be to prime DC generation system
The DC source of system and rear class single-phase full-bridge inverter output " triggering signal ", on the one hand cut off DC side
Direct current supply path and AC supply access, control in rear class single-phase full-bridge inverter the most simultaneously
The conducting of bridging and the transistor brachium pontis of dc bus, with DC side in electricity generation system of releasing and AC
Dump energy, it is to avoid in electricity generation system, the dump energy of DC side and AC pours into remaining electrochemical capacitor,
There is the phenomenon that over-voltage breakdown bursts, to realize remaining electrochemical capacitor is protected, it is to avoid occur more
Serious safety failure and human safety issues.
The wherein reference voltage V in Fig. 8refArrange protection domain for from central value be VrefChange in voltage
Scope, such as from 50%VrefTo 150%VrefExcursion.
The wherein reference voltage V in Fig. 8refCan be fixing reference voltage, it is also possible to for Vin/ n, Vin
For DC bus-bar voltage, " n " is number n of bridging and the series connection electrolysis electric capacity of dc bus.Work as benchmark
Voltage Vref=VinDuring/n, reference voltage VrefWill be along with DC bus-bar voltage VinChange and change,
Protection circuit so can be made to be more suitable for large-scale input voltage change application.
Wherein the point of the sampled voltage in Fig. 8 can need not to gather simultaneously dc bus (+) voltage VinWith
All each point voltage V of series connection electrolysis electric capacity junction pointC2..., Vcn-1 and Vcn, even if only including portion
Divide sampled point can also realize same defencive function.
Wherein the comparator in Fig. 8 can realize multilevel iudge function by hardware, it is also possible to passes through software
Realize multilevel iudge function.
Embodiment 3
Fig. 9 is the block diagram of electrochemical capacitor fault secure circuit in a kind of three-phase new forms of energy DC power generation system band,
Including four parts: the DC source of grid-connected power generation system, electrochemical capacitor CE1 and CE2, quasiconductor
Inverter and protection circuit.After electrochemical capacitor CE1 and CE2 concatenation between bridging and dc bus, electrolysis
The positive pole of electric capacity CE1 connect dc bus (+), the negative pole of electrochemical capacitor CE2 connects positive pole and connects dc bus
(-)；The prime of electrochemical capacitor CE1 and CE2 connects the DC source of grid-connected power generation system, and rear class connects three
Phase full-bridge inverter, then by inductance La, inductance Lb, inductance Lc, electric capacity Ca, electric capacity Cb and electricity
The wave filter holding Cc composition is connected to AC UVW three phase network or load；Electrochemical capacitor CE1 is just
Pole and dc bus (+) junction point voltage Vin and electrochemical capacitor ce1 and ce2 concatenate midpoint electricity
The sample circuit that pressure Vc2 is respectively connected in protection circuit, with reference voltage V after sampled processing of circuitref
The protection domain arranged compares the scope of seeing if fall out；In protection circuit, the output of comparator is connected to
Panel in the DC source of grid-connected power generation system and semiconductor inverter or drive circuit, with according to need
DC source current supply circuit to be cut off and semiconductor inverter AC current supply circuit, and in semiconductor inverter
Turn on while brachium pontis transistor.
In Fig. 9, semiconductor inverter is three-phase full-bridge inverter, by transistor Qa1 and Qa2, Qb1
With Qb2, Qc1 and Qc2 separately constitute 3 brachium pontis A, B and C, between bridging and dc bus；
The brachium pontis A of transistor Qa1 and Qa2 composition, after the midpoint of brachium pontis A is connected with inductance La, through inductance
La and electric capacity Ca, electric capacity Cc and AC U phase are connected；The brachium pontis B of transistor Qb1 and Qb2 composition,
After the midpoint of brachium pontis B is connected with inductance Lb, through inductance Lb and electric capacity Ca, electric capacity Cb and AC V
It is connected；The brachium pontis C of transistor Qc1 and Qc2 composition, after the midpoint of brachium pontis C is connected with inductance Lc,
It is connected through inductance Lb and electric capacity Cb, electric capacity Cc and AC W phase.
Transistor Qa1, Qa2, Qb1, Qb2, Qc1 and Qc2 in Fig. 9, in three-phase full-bridge inverter
Being turned on and off of transistor is controlled according to the signal of panel or protection circuit by drive circuit.
When in Fig. 9 electrochemical capacitor CE1 and CE2 one of them break down inefficacy time, electrochemical capacitor connect
The voltage signal of some Vc2 can exceed reference voltage VrefProtection electricity after the protection domain arranged, in Fig. 9
Comparator in road will export to the DC source of prime DC power generation system and rear class three-phase full-bridge inverter
" triggering signal ", on the one hand cuts off direct current supply path and the AC supply access of DC side, another
Aspect controls bridging and one or more transistor bridges of dc bus in rear class three-phase full-bridge inverter simultaneously
The conducting of arm, with DC side in electricity generation system of releasing and the dump energy of AC, it is to avoid in electricity generation system
The dump energy of DC side and AC pours into remaining electrochemical capacitor, and the phenomenon that over-voltage breakdown bursts occurs,
To realize remaining electrochemical capacitor is protected, it is to avoid more serious safety failure and personal safety occur
Problem.
The wherein reference voltage V in Fig. 9refArrange protection domain for from central value be VrefChange in voltage
Scope, such as from 50%VrefTo 150%VrefExcursion.
The wherein reference voltage V in Fig. 9refCan be fixing reference voltage, it is also possible to for Vin/ 2, Vin
For DC bus-bar voltage.Work as reference voltage Vref=VinWhen/2, reference voltage VrefWill be along with dc bus
Voltage VinChange and change, so can make protection circuit be more suitable for large-scale input voltage change
Application.
Wherein the point of the sampled voltage in Fig. 9 can need not to gather simultaneously dc bus (+) voltage VinWith
The voltage V of series connection electrolysis electric capacity junction pointC2Even if only including fractional-sample point and can also realizing same guarantor
Protective function.
Wherein the comparator in Fig. 9 can realize multilevel iudge function by hardware, it is also possible to passes through software
Realize multilevel iudge function.
Embodiment 4
When the DC bus-bar voltage in new forms of energy DC power generation system is increased to use more than 2 electrolysis
Failure of removal inspection when capacitance series reaches dc bus insulation pressure requirement, to concatenation electrochemical capacitor
Survey particularly important, it is necessary to use special protection circuit to carry out failure of removal protection.
Figure 10 is multiple electrochemical capacitor fault secure circuits in a kind of three-phase new forms of energy DC power generation system band
Block diagram, including four parts: the DC source of grid-connected power generation system, multiple electrochemical capacitor CE1,
CE2 ..., Cn-1 and Cn, semiconductor inverter and protection circuit.Electrochemical capacitor CE1, CE2 ...,
Cn-1 and Cn concatenation after bridging with dc bus between, the positive pole of electrochemical capacitor CE1 connect dc bus (+),
The negative pole of electrochemical capacitor CEn connect positive pole connect dc bus (-)；Electrochemical capacitor CE1 to CEn forms electricity
The prime solving electric capacity string connects the DC source of grid-connected power generation system, and rear class connects three-phase full-bridge inverter, then leads to
Cross the wave filter of inductance La, inductance Lb, inductance Lc, electric capacity Ca, electric capacity Cb and electric capacity Cc composition even
It is connected to AC UVW three phase network or load；Electrochemical capacitor CE1 positive pole and dc bus (+) company
Junction voltage Vin, the concatenation mid-point voltage Vc2 ... of electrochemical capacitor CE1 and CE2, electrochemical capacitor CEn-2
Concatenation mid-point voltage Vcn-1, the concatenation mid-point voltage Vcn of electrochemical capacitor CEn-1 and CEn with CEn-1
The sample circuit being respectively connected in protection circuit, is arranged with reference voltage V ref after sampled processing of circuit
Protection domain compares the scope of seeing if fall out；In protection circuit, the output of comparator is connected to new forms of energy
Panel in the DC source of electricity generation system and semiconductor inverter or drive circuit, to control as required
DC source current supply circuit and the cut-out of semiconductor inverter AC current supply circuit, and in semiconductor inverter
The conducting of brachium pontis transistor.
In Figure 10, semiconductor inverter is three-phase full-bridge inverter, by transistor Qa1 and Qa2, Qb1
With Qb2, Qc1 and Qc2 separately constitute 3 brachium pontis A, B and C, between bridging and dc bus；
The brachium pontis A of transistor Qa1 and Qa2 composition, after the midpoint of brachium pontis A is connected with inductance La, through inductance
La and electric capacity Ca, electric capacity Cc and AC U phase are connected；The brachium pontis B of transistor Qb1 and Qb2 composition,
After the midpoint of brachium pontis B is connected with inductance Lb, through inductance Lb and electric capacity Ca, electric capacity Cb and AC V
It is connected；The brachium pontis C of transistor Qc1 and Qc2 composition, after the midpoint of brachium pontis C is connected with inductance Lc,
It is connected through inductance Lb and electric capacity Cb, electric capacity Cc and AC W phase.
When one of them mistake of breaking down of electrochemical capacitor string of electrochemical capacitor CE1 to CEn composition in Figure 10
During effect, the voltage signal of the junction point that electrochemical capacitor is corresponding can exceed reference voltage VrefThe protection model arranged
After enclosing, the comparator in protection circuit in Figure 10 will to the DC source of prime DC power generation system and after
Level three-phase full-bridge inverter output " triggering signal ", on the one hand cut off DC side direct current supply path and
AC supply access, controls bridging and dc bus in rear class three-phase full-bridge inverter the most simultaneously
The conducting of transistor brachium pontis, with DC side in electricity generation system of releasing and the dump energy of AC, it is to avoid
In electricity generation system, the dump energy of DC side and AC pours into remaining electrochemical capacitor, and over-voltage breakdown occurs
The phenomenon burst, to realize protecting remaining electrochemical capacitor, it is to avoid more serious safety event occurs
Barrier and human safety issues.
The wherein reference voltage V in Figure 10refArrange protection domain for from central value be VrefVoltage become
Change scope, such as from 50%VrefTo 150%VrefExcursion.
The wherein reference voltage V in Figure 10refCan be fixing reference voltage, it is also possible to for Vin/ n,
VinFor DC bus-bar voltage, " n " is number n of bridging and the series connection electrolysis electric capacity of dc bus.Work as base
Quasi-voltage Vref=VinDuring/n, reference voltage VrefWill be along with DC bus-bar voltage VinChange and change,
Protection circuit so can be made to be more suitable for large-scale input voltage change application.
Wherein the point of the sampled voltage in Figure 10 can need not to gather simultaneously dc bus (+) voltage Vin
All each point voltage V with series connection electrolysis electric capacity junction pointC2..., Vcn-1 and Vcn, even if only including
Fractional-sample point can also realize same defencive function.
Wherein the comparator in Figure 10 can realize multilevel iudge function by hardware, it is also possible to passes through software
Realize multilevel iudge function.
It is only presently preferred embodiments of the present invention in sum, is not used for limiting the enforcement model of the present invention
Enclose.The most all equivalence changes made according to the content of scope of the present invention patent and modification, all should be this
Bright technology category.
Claims (4)
1. a protection circuit for capacitive faults, in electricity generation system, described electricity generation system includes leading to
Crossing dc bus and connect DC source, semiconductor inverter, the inverter other end connects AC；Direct current is female
The electric capacity with buffering and filter function it is in series with more than 2 or 2 between line；It is characterized in that: described
Protection circuit include sample circuit, comparator and reference voltage module；Wherein:
Described sample circuit is attached with the point that concatenates of dc bus and series capacitance, and carries out electricity
Pressure sampling；
Described comparator connects sample circuit and reference voltage module respectively, by judging that sample circuit is adopted
Whether the sampled voltage of collection exceedes the reference voltage range arranged in reference voltage module is done protection judgement,
The most then trigger protection function.
The protection circuit of capacitive faults the most according to claim 1, it is characterised in that: described guarantor
Protective function include by comparator send protection trigger signal cut prime DC source supply access and
The supply access of the AC of rear class.
The protection circuit of capacitive faults the most according to claim 1 and 2, it is characterised in that: described
Defencive function include the protection sent by comparator trigger signal control in rear class semiconductor inverter across
Connect the conducting of transistor brachium pontis with dc bus, in electricity generation system of releasing in DC side and AC
Electric energy, it is to avoid in electricity generation system, the electric energy of DC side and AC pours into remaining electric capacity.
The protection circuit of capacitive faults the most according to claim 1, it is characterised in that: described half
Conductor inverter is single-phase inverter or three-phase inverter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610490063.9A CN105958436A (en) | 2016-06-29 | 2016-06-29 | Capacitor failure protection circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610490063.9A CN105958436A (en) | 2016-06-29 | 2016-06-29 | Capacitor failure protection circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105958436A true CN105958436A (en) | 2016-09-21 |
Family
ID=56902921
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610490063.9A Pending CN105958436A (en) | 2016-06-29 | 2016-06-29 | Capacitor failure protection circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105958436A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112350282A (en) * | 2020-11-18 | 2021-02-09 | 深圳市永联科技股份有限公司 | Method for preventing overvoltage leakage liquid failure of aluminum electrolytic capacitor |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0638360A (en) * | 1992-07-20 | 1994-02-10 | Toyota Autom Loom Works Ltd | Deterioration and failure diagnosis system for capacitor |
| EP1858148A1 (en) * | 2006-02-24 | 2007-11-21 | Mitsubishi Denki Kabushiki Kaisha | System-cooperative inverter |
| CN104512274A (en) * | 2013-10-04 | 2015-04-15 | 三星Sdi株式会社 | Electric vehicle power conversion system |
-
2016
- 2016-06-29 CN CN201610490063.9A patent/CN105958436A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0638360A (en) * | 1992-07-20 | 1994-02-10 | Toyota Autom Loom Works Ltd | Deterioration and failure diagnosis system for capacitor |
| EP1858148A1 (en) * | 2006-02-24 | 2007-11-21 | Mitsubishi Denki Kabushiki Kaisha | System-cooperative inverter |
| CN104512274A (en) * | 2013-10-04 | 2015-04-15 | 三星Sdi株式会社 | Electric vehicle power conversion system |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112350282A (en) * | 2020-11-18 | 2021-02-09 | 深圳市永联科技股份有限公司 | Method for preventing overvoltage leakage liquid failure of aluminum electrolytic capacitor |
| CN112350282B (en) * | 2020-11-18 | 2023-07-25 | 深圳市永联科技股份有限公司 | Method for preventing overvoltage and leakage failure of aluminum electrolytic capacitor |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI439024B (en) | Cascade frequency converter and power unit with bypass module thereof | |
| CN102006007B (en) | Motor control system of electric automobile | |
| CN104767194B (en) | A kind of high voltage power transmission current conversion station over-pressure safety device | |
| CN111987706B (en) | Current-limiting type controllable lightning arrester, current converter, power transmission system and control method | |
| CN104730441A (en) | Thyristor fault detecting device | |
| CN103022978A (en) | Under-voltage protection circuit for multi-pulse-wave rectifying circuit | |
| CN106300309A (en) | A kind of flexible direct current electric network fault current limiter with fast restoration capabilities | |
| CN201562962U (en) | Sensor protective circuit | |
| CN103490602B (en) | The suppression circuit of VCE oscillating voltage during IGBT bridgc arm short | |
| CN104810793A (en) | Transformer neutral point direct current blocking device | |
| CN112670961A (en) | Short-circuit protection device and protection method for bus of frequency converter | |
| CN110518545A (en) | Hybrid high voltage DC breaker based on bidirectional current limiting module | |
| CN103647263A (en) | DC circuit breaker based on half-control electric-power electronic devices | |
| CN105958436A (en) | Capacitor failure protection circuit | |
| CN104734185A (en) | Tokamak plasma disruption energy processing device and processing method | |
| CN205811511U (en) | A kind of protection circuit of capacitive faults | |
| CN201378730Y (en) | Power circuit breaker protective circuit | |
| CN204597457U (en) | Transformer neutral point direct current is every straight device | |
| CN209267432U (en) | A kind of LCL filtering gird-connected inverter protection circuit | |
| CN201490917U (en) | Circuit for restraining high-frequency common mode voltage | |
| CN203166469U (en) | Phase sequence protective relay | |
| CN205646810U (en) | Well high voltage electric network arc extinction protection device | |
| CN103490406A (en) | Arc extinction device for solving problem of interphase short circuit according to full resistance method | |
| CN210693443U (en) | Short-circuit protection device for bus of frequency converter | |
| CN203522176U (en) | Arc extinction device for solving problem of interphase short circuit according to full resistance method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20160921 |