CN207559576U - Energy-storage system and energy accumulation current converter - Google Patents
Energy-storage system and energy accumulation current converter Download PDFInfo
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- CN207559576U CN207559576U CN201721828943.9U CN201721828943U CN207559576U CN 207559576 U CN207559576 U CN 207559576U CN 201721828943 U CN201721828943 U CN 201721828943U CN 207559576 U CN207559576 U CN 207559576U
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Abstract
The utility model provides a kind of energy-storage system and energy accumulation current converter.Energy accumulation current converter is mainly by including cascade two-way DC/DC modules and two-way DC/AC modules, the low-pressure side of two-way DC/DC modules is used to access accumulator group, the high-pressure side of two-way DC/AC modules is used to be connected to AC network, two-way DC/DC modules include at least two two-way DC/DC circuits in parallel, each two-way DC/DC circuits with an accumulator for connecting, to realize the charge/discharge function to accumulator.The energy accumulation current converter of the utility model is by the way that two-way DC/DC modules to be arranged to be made of the two-way DC/DC circuits of multiple parallel connections, each two-way DC/DC circuits are for one battery of access, there is two-way DC/DC modules higher boosting when to extend flexibility, so that energy accumulation current converter advantageously accounts for energy storage system capacity allocation problem, cost is reduced, and improves system reliability.
Description
【Technical field】
The utility model is related to power supply control technical field more particularly to a kind of energy accumulation current converter and use the energy storage unsteady flow
The energy-storage system of device.
【Background technology】
With the fast development of distributed generation technology, micro-capacitance sensor and intelligent grid, the effect of energy-storage system is increasingly heavier
Will, wherein bidirectional energy-storage current transformer realizes that bidirectional energy of the DC energy storage battery (such as accumulator group) between AC network passes
It passs, is by the key equipment of energy-storage battery access electric system.The electric energy transfer that energy accumulation current converter can have more than needed by night or on ordinary days
It is stored to energy-storage travelling wave tube, and power grid is fed back to balance power grid peak valley in power grid electric energy deficiency, pass through energy accumulation current converter
Control strategy design, can realize the work(such as charge/discharge management to battery pack, the smooth, islet operation of exchange side load power
Energy.Meanwhile energy accumulation current converter has for wind energy, solar energy, tide etc. in intermittent grid-connected power generation system, it can be very
Smooth generation of electricity by new energy output, improves micro-capacitance sensor power supply quality, makes extensive renewable energy system safe and reliable in big degree
Ground is connected to the grid, and really embodies " green energy transformation ".
In existing energy-storage system, since existing bidirectional energy-storage converter structure is unreasonable, the voltage of single battery is low, holds
Measure it is small, so the battery in energy-storage system is all to get up to form battery cluster by multiple single battery connection in series-parallel, to meet energy storage system
To the requirement of the voltage of battery and capacity in system.However, the parallel-connection structure in battery pack limits the voltage power supply model of accumulator
It encloses, cascaded structure reduces the reliability of system.Since the internal resistance between accumulator is not completely equivalent, so entire accumulator group
Charge/discharge distribution of the total current between each battery it is uneven, cause the equal properties of flow between battery pack bad.This
Outside, the capacity configuration of existing energy-storage system lacks flexibility, can not be adjusted at any time once after the capacity of accumulator group prepares
It is whole, cause in the environment of being run for plurality of groups of storage batteries, need to be equipped with multiple energy accumulation current converters, cost is caused to increase.
【Utility model content】
The primary and foremost purpose of the utility model is to provide a kind of energy storage of convenience to battery number is adjusted in battery pack
Current transformer.
The another object of the utility model is to provide a kind of energy-storage system using above-mentioned energy accumulation current converter.
To realize the purpose, the utility model adopts the following technical solution：
A kind of energy accumulation current converter, including cascade two-way DC/DC modules and two-way DC/AC modules, the two-way DC/DC moulds
For accessing accumulator group, the exchange side of the two-way DC/AC modules is used to be connected to AC network the low-pressure side of block,
In, the two-way DC/DC modules include at least two two-way DC/DC circuits in parallel, and each two-way DC/DC circuits are used for
It is connect with an accumulator.
Preferably, the two-way DC/DC circuits include two step-up/step-down circuits in parallel, and the step-up/step-down circuit includes connecting
Two power devices connect.
Preferably, the two-way DC/DC circuits further include to be connected across first capacitance between accumulator the two poles of the earth；
The power device includes an IGBT, in two IGBT of the step-up/step-down circuit, the emitter and second of first IGBT
The collector of a IGBT is connected；In first step-up/step-down circuit, the line between two IGBT passes through the first energy storage inductor and institute
The anode connection of the first capacitance is stated, the emitter of second IGBT is connect with the cathode of first capacitance；Second buck
In circuit, the line between two IGBT is connect by the second energy storage inductor with the cathode of first capacitance, first IGBT
Collector connect with the anode of first capacitance.
Preferably, the two-way DC/DC circuits, which further include, is connected on high-tension side second electricity of each step-up/step-down circuit
Hold.
Preferably, the two-way DC/AC modules include be sequentially connected in series DC support capacitance, inversion/rectifier circuit and
Exchange side filter circuit；The DC support capacitance is connected across two output terminals of the two-way DC/DC module high voltages side；It is described
Exchange side filter circuit is additionally operable to be connected on AC network.
Preferably, the DC support capacitance include series connection the first Support Capacitor and the second Support Capacitor, described first
Line between Support Capacitor and the second Support Capacitor is additionally operable to connect with a phase line in three-phase AC grid；It is described inverse
Change/rectifier circuit includes two bridge arms, and each bridge arm includes the IGBT of two concatenations, and described two bridge arms are used to correspond to and three
Other two phase lines connection in phase AC network.
Preferably, the inversion/rectifier circuit is Three-Phase PWM Rectifier.
Preferably, the inversion/rectifier circuit is three-phase Half bridge rectifier circuit, including three busbares with AC network
Three bridge arms to connect one to one；One of them described bridge arm is made of the fly-wheel diode of two series connection, other two bridge
Arm includes the IGBT of two concatenations.
Preferably, the exchange side filter circuit is LCL filter circuits.
In addition, a kind of energy-storage system is also provided, the energy storage unsteady flow being electrically connected including accumulator group and with the accumulator group
Device, the energy accumulation current converter are above-mentioned energy accumulation current converter, multiple accumulators and the two-way DC/DC moulds in the accumulator group
Multiple two-way DC/DC circuits in the block connect one to one.
Compared with prior art, the utility model has following advantage：
The energy accumulation current converter of the utility model is mainly made of two-way DC/DC modules and two-way DC/AC module-cascades,
In, the two-way DC/DC moulds each two-way DC/DC circuits in the block are for accessing a battery cell, in two-way DC/DC modules
Each DC/DC circuits between be connected in parallel, can solve entire accumulator group in charge and discharge to avoid the circulation between battery pack
In the process total current distributed between each battery it is uneven and the problem of cause equal properties of flow bad.In addition, needing to battery
When battery number in group is adjusted, the DC/DC circuits presents in the corresponding two-way DC/DC modules of additions and deletions, without additional
Energy accumulation current converter is equipped with, facilitates the flexible configuration to entire energy storage system capacity, and reduce cost.
【Description of the drawings】
Fig. 1 is a kind of circuit diagram of embodiment of the energy-storage system of the utility model；
Fig. 2 is the circuit diagram of the another embodiment of the energy-storage system of the utility model；
Fig. 3 is the circuit diagram of another embodiment of the energy-storage system of the utility model.
【Specific embodiment】
The utility model is further described with exemplary embodiment below in conjunction with the accompanying drawings, it is wherein identical in attached drawing
Label all refers to identical component.In addition, if the detailed description of known technology is for showing the feature of the utility model
It is unnecessary, then omits it.
The utility model discloses a kind of energy-storage system and its energy accumulation current converter of use.Energy accumulation current converter is used to complete electric power storage
Energy conversion between pond group and AC network realizes that AC network charges to accumulator group and accumulator group is to power grid
It discharges.The energy accumulation current converter include by the two-way DC/DC modules that multiple two-way DC/DC circuit in parallel form with it is two-way
DC/AC module-cascades form.
Wherein, each two-way DC/DC circuits realize the discharge charge electric work of the accumulator for accessing an accumulator
Energy.The two-way DC/DC circuits include two step-up/step-down circuits in parallel, the low-pressure side set on the step-up/step-down circuit low-pressure side
Filter circuit and set on the on high-tension side high-pressure side filter circuit of step-up/step-down circuit.The low-pressure side filtering of the two-way DC/DC circuits
Circuit can filter out the current/voltage harmonic wave of low-pressure side radio-frequency component, and inhibit high frequency ripple.
Each step-up/step-down circuit includes two transistors connected and correspondence and two antiparallel afterflows of transistor
Diode.Wherein, the transistor is preferably insulated gate bipolar transistor, and two transistors are configured as one
Boost transistor and a decompression transistor.
The two-way DC/AC modules include DC support capacitance, inversion/rectifier circuit and the exchange side filter being sequentially connected in series
Wave circuit.The DC support capacitance is connected across between the output terminal of the two-way DC/DC module high voltages side, the exchange side filter
Wave circuit is preferably LCL filter circuits, for being connect with AC network, is opened with filtering out the high-frequency harmonic of power grid generation and current transformer
Close the high-frequency harmonic of frequency.
In the energy accumulation current converter of the utility model, by being arranged to two-way DC/DC modules by can access an electric power storage
Multiple two-way DC/DC circuit in parallel compositions in pond, are needing to be adjusted the capacity of accumulator group, that is, are increasing and decreasing accumulator number
When, it can be by the number of two-way DC/DC circuits in parallel in the two-way DC/DC modules of additions and deletions, to be adapted to the access of newly-increased accumulator
Or the removal of accumulator, it realizes the flexible configuration to entire battery energy storage system capacity, is easy to extend, facilitates operational management.Separately
Outside, each accumulator by a two-way DC/DC circuits access energy-storage system rather than multiple accumulators first connect after it is in parallel again
Access energy-storage system in, can to avoid being not completely equivalent due to accumulator internal resistance caused by properties of flow it is bad the problem of.
It should be understood that ground, the energy-storage system further include the transformer being connect with the energy accumulation current converter exchange side.In addition,
Corresponding direct current buffer circuit, lightning protection circuit can be also designed as needed.
The energy-storage system of the utility model and the structure and working principle of energy accumulation current converter for ease of understanding, lead to below
Specific embodiment is crossed to be illustrated.
Embodiment one
As shown in FIG. 1, FIG. 1 is the circuit diagrams of the energy-storage system of the utility model, and the institute of the utility model is shown
State energy accumulation current converter (non-label, similarly hereinafter).The energy accumulation current converter includes cascade two-way DC/DC modules (non-label, similarly hereinafter)
With two-way DC/AC modules 200.
The two-way DC/DC modules include at least two two-way DC/DC circuits 100 in parallel, each two-way DC/DC
Circuit 100 accesses accumulator 500 in the energy-storage system for being connect with an accumulator 500.
The two-way DC/DC circuits 100 include two step-up/step-down circuits 10 in parallel, set on 10 low-pressure side of step-up/step-down circuit
Low-pressure side filter circuit and set on 10 on high-tension side high-pressure side filter circuit of step-up/step-down circuit.
Specifically, each step-up/step-down circuit 10 includes the transistor and two fly-wheel diodes of two series connection, described in two
Transistor is preferably IGBT (Insulate-Gate Bipolar Transistor, insulated gate bipolar transistor), described
IGBT is divided into a boost transistor and a decompression transistor, two fly-wheel diodes and two under the allotment of control strategy
A transistor corresponds inverse parallel connection, thus also corresponding configuration is two poles of booster diode and decompression to two fly-wheel diodes
Pipe, and booster diode and decompression coupled in parallel, buck diode are in parallel with boost transistor.
Wherein, a step-up/step-down circuit 10 includes decompression transistor VT1, boost transistor VT2, booster diode VD1, drop
Press the emitter and collector of the anode and cathode and the decompression transistor VT1 of diode VD2, the booster diode VD1
It is correspondingly connected with, the anode and cathode of the buck diode VD2 is corresponding with the emitter and collector of the boost transistor VT2
Connection.
Another step-up/step-down circuit 10 includes boost transistor VT3, decompression transistor VT4, buck diode VD3, boosting
The anode and cathode of diode VD4, the buck diode VD3 and the emitter and collector pair of the boost transistor VT3
It should connect, the anode and cathode of the booster diode VD4 are corresponding with the emitter and collector of the decompression transistor VT4 to be connected
It connects.
It should be appreciated that the device in two step-up/step-down circuits is identical, connection structure is also identical, and transistor is in control plan
Different on off states is worked under allotment slightly and completes boosting and the buck functionality of circuit, i.e. in first step-up/step-down circuit
First transistor be decompression transistor VT1, when second transistor is boost transistor VT2, second step-up/step-down circuit
First transistor be boost transistor VT3, second transistor is decompression transistor VT4.
The low-pressure side filter circuit includes the first capacitance C1, with the corresponding the two poles of the earth for being connected across accumulator of polarity, and
And the anode of the first capacitance C1 passes through emitters of the first energy storage inductor L1 with the decompression transistor VT1 and the boosting
The collector connection of transistor VT2, the cathode of the first capacitance C1 pass through the transmitting of the second energy storage inductor L2 and boost transistor VT3
Pole is connected with the collector of decompression transistor VT4.In addition, the emitter of VT2 and the collector of VT3 also correspond to and the first electricity respectively
The cathode of appearance is connected with anode.
The high-pressure side filter circuit includes second capacitance C2, C3, anode and the decompression transistor of the second capacitance C2
The collector of VT1 is connected, and cathode is connected with the emitter of boost transistor VT2；The anode and boost transistor of second capacitance C3
The collector of VT3 is connected, and cathode is connected with being depressured the emitter of transistor.The anode and the second capacitance C3 of the second capacitance C2
Cathode be additionally operable to be correspondingly connected with the loads of the two-way DC/DC circuits (in present embodiment, the load be positioned at two-way
The two-way DC/AC modules of DC/DC module next stage) anode and cathode.
In the present embodiment, the two-way DC/AC modules 200 include DC support capacitance, Three-Phase PWM Rectifier 20 and
Positioned at the LCL filter circuits 21 of 20 exchange side of Three-Phase PWM Rectifier.The as above-mentioned inversion of the Three-Phase PWM Rectifier 20/whole
Flow device.The Three-Phase PWM Rectifier 20 is connected to AC network via the LCL filter circuits and transformer 300.
Wherein, the transistor and two and the crystal that each bridge arm of the Three-Phase PWM Rectifier 20 is connected by two
Pipe corresponds to the fly-wheel diode composition of inverse parallel connection, and the both ends of each bridge arm are connected to the DC support electricity by busbar
On the two poles of the earth of appearance, the midpoint of each bridge arm is connected to by the LCL filter circuits in a phase line of AC network.Two-way
When DC/AC modules work, the drive signal of two transistors is complementary above and below each bridge arm, two neighboring bridge arm angle of flow difference
120°。
The operation principle of the energy accumulation current converter of the utility model is：
When accumulator Battrey discharges, two-way DC/DC modules work in pressure-increasning state, load current and predetermined pros
To identical, by the way that boost transistor VT2 and booster diode VD1 is controlled to realize, circuit boosts, by controlling boost transistor VT3
Circuit boosting is realized with booster diode VD4, and accumulator discharges energy by two-way DC/DC modules, two-way DC/AC modules to power grid
Amount；When accumulator Battrey charges, two-way DC/DC modules work in decompression state, load current and predetermined positive direction phase
Instead, control decompression transistor VT1, VT4 and buck diode VD2, VD3 realize circuit decompression, and accumulator passes through two-way DC/DC moulds
Block, two-way DC/AC modules draw energy from power grid.
In the utility model, the transistor is preferably insulated gate bipolar transistor, first capacitance, the second capacitance
For polar capacitor.
Embodiment two
As shown in Fig. 2, in the present embodiment, the energy accumulation current converter is similar in embodiment one, and difference is, institute
State the first DC support capacitance C4 and the second DC support capacitance C5 that DC support capacitance includes series connection, the DC support electricity
A phase line for holding a bridge arm for forming inversion/rectifier and AC network connects.Wherein, the first DC support capacitance
The capacitance of C4 and the second DC support capacitance C5 are identical.
Compared with the current transformer of embodiment one, DC support capacitance has drawn midpoint, by the identical pressure of two groups of capacitances
Capacitance forms a bridge arm of inversion/rectifier, reduces two insulated gate bipolar transistors and two reverse parallel connection afterflows
Diode reduces two sets of driving circuits, and control is further simplified, so as to substantially increase system reliability, cooling fin
Size and two-way DC/AC modules volume can also greatly reduce, and then system cost is greatly reduced.
Embodiment three
As shown in figure 3, in the present embodiment, the energy accumulation current converter is similar in embodiment one, and difference is, institute
The one of bridge arm for stating Three-Phase PWM Rectifier 20 is only made of the fly-wheel diode of two series connection, reduces two insulated gates
Bipolar transistor reduces two sets of driving circuits, and control system further simplifies, reliable so as to substantially increase system
Property, heat sink sizes and two-way DC/AC modules volume can also greatly reduce, and then system cost is greatly reduced.
Although having been illustrated with some exemplary embodiments of the utility model above, those skilled in the art will
Understand, in the case of the principle or spirit for not departing from the utility model, these exemplary embodiments can be made a change, this
The range of utility model is limited by claim and its equivalent.
Claims (10)
1. a kind of energy accumulation current converter, including cascade two-way DC/DC modules and two-way DC/AC modules, the two-way DC/DC modules
Low-pressure side for accessing accumulator group, the exchange side of the two-way DC/AC modules is for being connected to AC network, feature
It is, the two-way DC/DC modules include at least two two-way DC/DC circuits in parallel, and each two-way DC/DC circuits are used
It is connect in an accumulator.
2. energy accumulation current converter according to claim 1, which is characterized in that the two-way DC/DC circuits include in parallel two
A step-up/step-down circuit, the step-up/step-down circuit include two power devices of connection.
3. energy accumulation current converter according to claim 2, which is characterized in that the two-way DC/DC circuits further include for across
First capacitance being connected between accumulator the two poles of the earth；
The power device includes an IGBT, in two IGBT of the step-up/step-down circuit, the emitter of first IGBT with
The collector of second IGBT is connected；In first step-up/step-down circuit, the line between two IGBT passes through the first energy storage inductor
It is connect with the anode of first capacitance, the emitter of second IGBT is connect with the cathode of first capacitance；Second rises
In reduction voltage circuit, the line between two IGBT is connect by the second energy storage inductor with the cathode of first capacitance, first
The collector of IGBT is connect with the anode of first capacitance.
4. energy accumulation current converter according to claim 3, which is characterized in that the two-way DC/DC circuits, which further include, to be connected to
Each on high-tension side second capacitance of step-up/step-down circuit.
5. according to the energy accumulation current converter described in any one of claim 1-4, which is characterized in that the two-way DC/AC modules packet
Include the DC support capacitance being sequentially connected in series, inversion/rectifier circuit and exchange side filter circuit；The DC support capacitance bridging
Two output terminals in the two-way DC/DC module high voltages side；The exchange side filter circuit is additionally operable to be connected to AC network
On.
6. energy accumulation current converter according to claim 5, which is characterized in that the DC support capacitance includes the first of series connection
Support Capacitor and the second Support Capacitor, the line between first Support Capacitor and the second Support Capacitor are additionally operable to intersect with three
Phase line connection in galvanic electricity net；
Inversion/the rectifier circuit includes two bridge arms, and each bridge arm includes the IGBT of two concatenations, and described two bridge arms are used
It is connect in corresponding with two phase lines other in three-phase AC grid.
7. energy accumulation current converter according to claim 5, which is characterized in that the inversion/rectifier circuit is whole for three-phase PWM
Flow device.
8. energy accumulation current converter according to claim 5, which is characterized in that the inversion/rectifier circuit is three-phase half-bridge
Rectification circuit, three bridge arms to connect one to one including three busbares with AC network；One of them described bridge arm is by two
The fly-wheel diode composition of a series connection, other two bridge arm include the IGBT of two concatenations.
9. energy accumulation current converter according to claim 5, which is characterized in that the exchange side filter circuit is LCL filtered electricals
Road.
10. a kind of energy-storage system, the energy accumulation current converter being electrically connected including accumulator group and with the accumulator group, feature exist
In, the energy accumulation current converter be the energy accumulation current converter in claim 1 to 9 described in any one, it is more in the accumulator group
A accumulator connects one to one with two-way DC/DC moulds multiple two-way DC/DC circuits in the block.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721828943.9U CN207559576U (en) | 2017-12-22 | 2017-12-22 | Energy-storage system and energy accumulation current converter |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721828943.9U CN207559576U (en) | 2017-12-22 | 2017-12-22 | Energy-storage system and energy accumulation current converter |
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| CN207559576U true CN207559576U (en) | 2018-06-29 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109116257A (en) * | 2018-09-20 | 2019-01-01 | 江苏为恒智能科技有限公司 | Battery set charge/discharge detection device |
-
2017
- 2017-12-22 CN CN201721828943.9U patent/CN207559576U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109116257A (en) * | 2018-09-20 | 2019-01-01 | 江苏为恒智能科技有限公司 | Battery set charge/discharge detection device |
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