CN110474366A - A kind of control system for three-phase tri-level photovoltaic combining inverter - Google Patents
A kind of control system for three-phase tri-level photovoltaic combining inverter Download PDFInfo
- Publication number
- CN110474366A CN110474366A CN201910716888.1A CN201910716888A CN110474366A CN 110474366 A CN110474366 A CN 110474366A CN 201910716888 A CN201910716888 A CN 201910716888A CN 110474366 A CN110474366 A CN 110474366A
- Authority
- CN
- China
- Prior art keywords
- circuit
- voltage
- driving
- plate
- control system
- 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
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M7/00—Conversion of ac power input into dc power output; Conversion of dc power input into ac power output
- H02M7/42—Conversion of dc power input into ac power output without possibility of reversal
- H02M7/44—Conversion of dc power input into ac power output without possibility of reversal by static converters
- H02M7/48—Conversion of dc power input into ac power output without possibility of reversal by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M7/483—Converters with outputs that each can have more than two voltages levels
- H02M7/487—Neutral point clamped inverters
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A30/00—Adapting or protecting infrastructure or their operation
- Y02A30/60—Planning or developing urban green infrastructure
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/56—Power conversion systems, e.g. maximum power point trackers
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Inverter Devices (AREA)
Abstract
The present invention discloses a kind of control system for three-phase tri-level photovoltaic combining inverter comprising main power amplifier board, driving plate, isolation drive power panel, voltage and current sampling plate and DSP control system composition；Driving plate is equipped with driving circuit；Isolation drive power panel is inserted in driving plate board connector by plate, for four driving IC power supply in driving plate, then driving plate is inserted on main power amplifier board board connector by plate drives each IGBT module again, main power amplifier board is connect after inductance filter with voltage and current sampling plate, sampling plate is equipped with the sample circuit of acquisition network voltage and grid-connected current and soft opens circuit, for the soft circuit that opens for being pre-charged to the dc-link capacitance on main power amplifier board, DC-bus voltage sampling circuit acquires the DC voltage of DC bus top and bottom capacitor respectively.Each hardware is constituted standardization, modularization by the application, its independent isolating is come, the development of photovoltaic DC-to-AC converter product is more advantageous to.
Description
Technical field
The present invention relates to the control system of inverter, especially a kind of control for three-phase tri-level photovoltaic combining inverter
System processed.
Background technique
As environment, energy problem become increasingly conspicuous, the utilization of renewable energy is the common focus that countries in the world are concerned about.
And power electronics, transformation of electrical energy technology are basis and the key link of its development, China's power electronic technique, transformation of electrical energy technology
After decades of development, significant effect is had been achieved for, the new energy electrical energy changer such as photovoltaic DC-to-AC converter is ripe day by day,
High efficiency, modularization, customization, greenization become its inexorable trend developed.
To obtain higher transfer efficiency and power grid quality, photovoltaic DC-to-AC converter is specifically related to following key technology:
(1) converter New Topological technology
Power electronic devices is the basis of converter, and the technological level of power electronic devices is not able to satisfy some spies still at present
Determine the needs of occasion, such as high-power field high frequency, high pressure and low EMI, is still a challenge to inversion transformation technique.Therefore, development is new
Circuit structure, study new control technology, improving the efficiency of power inverter, improving grid-connected quality is also parallel network reverse technology
The important directions of development.For at present, high-efficiency photovoltaic inverter uses the tri-level inversion structure of single-stage, and uses resonance soft
Efficiency can be improved in switching technique, reduces device pressure resistance, reduces harmonic wave, simplifies filter design, is current high-efficiency photovoltaic inversion
The research and development direction of device.
(2) optimisation technique of performance and cost
The performance and cost of photovoltaic DC-to-AC converter, which have become photovoltaic system, cannot be neglected important indicator, therefore, using height
The Technology of Power Conversion of effect, the system performance index design of optimization, by efficient, high performance photovoltaic DC-to-AC converter products application in light
Photovoltaic grid-connected field improves the utilization rate of photovoltaic energy, reduces loss, reduces inverter production and maintenance cost, is mesh
The research and development direction of preceding high-power photovoltaic inverter.High-efficiency photovoltaic inverter uses modularized design, can simplify design,
It is easy to maintain, it accomplishes scale production, to reduce production cost and research and development cost, pushes and realize high-power photovoltaic inverter
Industrial application.
(3) digital control strategy
It is digital control to have the characteristics that flexible, stable, easily scalable, simplified hardware circuit, therefore digital control technology exists
Photovoltaic DC-to-AC converter is rapidly developed.Under certain topological circuit basis, some Advanced Control Strategies and control method are drawn
Enter photovoltaic DC-to-AC converter, improve the dynamic property of photovoltaic DC-to-AC converter transformation of electrical energy, such as the control of locking phase loop voltag, vector controlled, solution
The control strategies such as coupling control, neural network, sliding moding structure play in terms of improving photovoltaic DC-to-AC converter dynamic property, improving efficiency
Good effect.
In order to improve transfer efficiency and improve grid-connected performance, meet the application of high-power occasion, and shorten exploitation
Period accelerates the research and development of product, reduces exploitation investment, mainly passes through following several technical approach.This is also that the industry is ground later
The direction studied carefully and technological difficulties.
(1) photovoltaic inverting system distribution module formula designing technique difficult point
The modularization of Photovoltaic Inverter, standardization can greatly reduce Photovoltaic Inverter research and development of products investment, accelerate to grind
Hair process.Technological difficulties and research emphasis are how to realize the segmentation of distributed converters itself, develop the big of 100kW grade
Power inverting module.The basic unit of bottom is its hardware foundation, and suitable basic unit is very important.Therefore, module
Change, standard customization are the Main Trends of The Development of photovoltaic DC-to-AC converter product, and the research of the relevant technologies is also the crucial difficult of quasi- breakthrough
Point.
(2) photovoltaic generating system OVERALL OPTIMIZA-TION DESIGN FOR technological difficulties
The selection of traditional design of photovoltaic power station, photovoltaic cell and photovoltaic DC-to-AC converter is to separate evaluation, generally requires visitor
Family is examined by multiple combinations test and for a long time, can separate superiority and inferiority, but the photovoltaic DC-to-AC converter of standard be can not be according to choosing
What photovoltaic cell characteristic and local climate actual conditions optimized, that is, it is unable to reach the optimum performance of system configuration.
Summary of the invention
The brief overview about the embodiment of the present invention is given below, in order to provide about certain aspects of the invention
Basic comprehension.It should be appreciated that outlined below is not about exhaustive general introduction of the invention.It is not intended to determine this hair
Bright key or pith, nor is it intended to limit the scope of the present invention.Its purpose only provides certain in simplified form
A little concepts, taking this as a prelude to a more detailed description discussed later.
According to the one aspect of the application, a kind of control system for three-phase tri-level photovoltaic combining inverter is provided,
The system includes main power amplifier board, driving plate, isolation drive power panel, voltage and current sampling plate and DSP control system composition；It drives
Movable plate is equipped with driving circuit；Isolation drive power panel is inserted in driving plate board connector by plate, is four in driving plate
A driving IC power supply, then driving plate is inserted on main power amplifier board board connector by plate drives each IGBT module again, main function
Rate plate connect after inductance filter with voltage and current sampling plate, and sampling plate is equipped with acquisition network voltage and grid-connected current is adopted
Sample circuit and it is soft open circuit, the soft circuit that opens is for being pre-charged the dc-link capacitance on main power amplifier board, DC bus
Voltage sampling circuit acquires the DC voltage of DC bus top and bottom capacitor respectively.
It wherein, include outside the drivings such as three level IGBT modules, dc-link capacitance and gate driving resistance on main power amplifier board
It encloses；In order to reduce the parasitic inductance of DC bus, system performance is improved, main power amplifier board uses four layers of pcb board structure, eliminates suction
Receive circuit, the plate arrangement layer of four layers of pcb board of main circuit is as follows: signals layer and three-phase alternating current of the upper layer for driving interface circuit are defeated
Cabling out, internal planes 1 are direct-flow positive pole plane, and internal planes 2 are used as direct current midpoint plane, and bottom is direct current cathode plane.Directly
Stream input terminal, three level IGBT modules, dc-link capacitance are directly connected in each power plane, the parasitism electricity of DC side
Sense is controlled in the range of very little, and the due to voltage spikes on DC bus is effectively reduced.
Preferably, three level IGBT modules choose the three level IGBT function of F3L75R07W2E3_B11 type of Infineon company
Rate module is realized.
680 μ F/400V alminium electrolytic condensers of the selection EPCOS company of dc-link capacitance, two strings two and rear pressure resistance are
800V, equivalent capacitance are 680 μ F.
Since each bridge arm (module) needs the driving of four tunnels, need using the driving suitable for selected three level IGBT module
The peripheral assembly of circuit design, driving chip should lack as far as possible, guarantee lesser PCB size.The protection that driving circuit has
Function such as under-voltage locking and short-circuit protection etc. will match with three level IGBT modules.Typical IGBT drive circuit should have simultaneously
There are input, the output signal function of isolation, and requires signal in driving circuit without transmission delay or delay very little, the application
The driving chip ACPL-332J of selection can easily meet these requirements.
It samples as follows with protecting circuit designed:
For DC-bus voltage sampling circuit: in order to be monitored in real time to DC bus lateral capacitance neutral balance situation
And overvoltage protection is provided, it needs to carry out voltage sample to two lateral capacitance of DC bus respectively.The sample circuit of DC bus-bar voltage
It is made of the difference channel that multiple 1% precision resistances bleeder circuit in series and high-operational amplifier TL074 are constituted.
For grid-connected current sample circuit: current sensor is realizing the feedback control of photovoltaic combining inverter, system guarantor
Shield, parameter, which shows etc. in multiple functions, plays extremely important effect, so must focus on it when selecting current transformer accurately
Degree and stability.The application samples grid-connected current using the 4644-X300 type current sensor of VAC company, Germany, should
Current transformer is replaced on the basis of traditional closed-loop Hall current sensor using the amorphous soft magnet piece with patented technology
Traditional Hall plate, to obtain brilliant performance, compared with conventional Hall current sensor, it has accuracy height, temperature
The advantages that characteristic is good, corresponding speed is fast, frequency range is wide.Sensor use ± 15V the dual power supply is electric current output side
Formula, so its output signal need to first pass through sampling resistor and carry out the conversion of one voltage of electric current, then through impedance matching, ratio, voltage
It is promoted, filtering is converted into the signal that can be received by DSP.
For line voltage sample circuit: gird-connected inverter realizes that another important link of cutting-in control is network voltage
Sampling, the accuracy and stability of voltage transformer are also particularly important.The application uses the TV19G type voltage of the Dechang Yao Hua company
Mutual inductor, the mutual inductor are that vacuum epoxy is filling, are directly welded in PCB circuit board, totally-enclosed, and dielectric strength reaches 10KV, and
Using slope film alloy-iron core, the linearity is better than 0.2%.Equally, which is also the electric current way of output, at following stage
Reason is similar to output current sampling circuit.
In addition, the control system of the application has carried out following design also directed to power supply:
The hardware system of photovoltaic combining inverter is made of multiple circuit boards, and a variety of direct currents are required on each circuit board
Source, each road power supply have different stability requirements, even need the different pcb boards of identical DC voltage, the electricity needed
It is also not identical to flow size, using the power source design of single module multiple-channel output, is difficult to meet this requirement, the road modular power source Zhong Ge is defeated
There are cross jammings between out, can not guarantee the stability of each road power supply output simultaneously.The application uses distributed DC power system
System, the power-supply system are made of an AC/DC Switching Power Supply (exchange leading portion power module) and multiple DC/DC conversion modules, hand over
Exchange is converted to the DC voltage of 12V, the bus as distributed DC power by stream leading portion.Dc bus is connected to inversion
On the different pcb boards of device hardware system, then the different DC voltages that each functional circuit needs are generated by onboard DC/DC module,
Such as 3.3V, ± 15V, 5V etc..
Distributed DC power system suitability is strong, has fine reliability and Electro Magnetic Compatibility, each section electricity of system
Source is independent, and partial power is smaller, not high to the power quality requirements of dc bus, and the DC/DC module of rear end ensure that output electricity
The stability of pressure, each subsystem are powered on the spot, and power supply loop is small, and the influence of line impedance is small, strong antijamming capability, and each power supply is whole
The current fluctuation at end will not influence each other, and not have rush of current interference between each other.
The DSP that the application is suitable for three-phase tri-level photovoltaic combining inverter also directed to above-mentioned hardware Construction designing is controlled
System, the DSP control system using the TMS320F28335 of TI company as control core, control system by DSP28335 core board and
Bottom plate composition, the pinboard (AdapterBoard) of bottom plate functioned as between control core and inverter, in pinboard
On devise the human-computer interaction interface interface of signal conditioning circuit and PWM interface circuit and system, as serial communication, keyboard,
Display etc..It is required according to the dead zone of 12 road pwm signal features of three-phase tri-level inverter and three level bridge arms, it is defeated to DSP
Pwm signal out has carried out reasonable configuration.
The application through the above scheme, compared with prior art, have the advantages that by each hardware constitute standardization,
Modularization comes its independent isolating, is more advantageous to the development of photovoltaic DC-to-AC converter product；In addition, traditional design of photovoltaic power station,
The selection of photovoltaic cell and photovoltaic DC-to-AC converter is to separate evaluation, generally requires client and examines by multiple combinations test and for a long time
Core, can separate superiority and inferiority, but the photovoltaic DC-to-AC converter of standard be can not be real according to the photovoltaic cell characteristic and local climate of selection
Border situation optimizes, that is, is unable to reach the optimum performance of system configuration, and the application is by by the inversion of photovoltaic generating system
The design of device system and power plant application configuration design synthesis consider, carry out whole design, and combine system design, structure design, heat
Design, EMC design etc., realize the best performance and Optimum cost of photovoltaic generating system entirety.
Detailed description of the invention
The present invention can be by reference to being better understood, wherein in institute below in association with description given by attached drawing
Have and has used the same or similar appended drawing reference in attached drawing to indicate same or similar component.The attached drawing is together with following
It is described in detail together comprising in the present specification and forming a part of this specification, and is used to that this is further illustrated
The preferred embodiment and explanation the principle of the present invention and advantage of invention.In the accompanying drawings:
Fig. 1 is Control system architecture block diagram of the invention；
Fig. 2 is main power circuit topological structure；
Fig. 3 is the driving circuit of IGBT module outer tube；
Fig. 4 is the driving circuit of IGBT module inner tube；
Fig. 5 is signal timing diagram；
Fig. 6 is down tube because parasitic turn-on occurs for miller capacitance；
Fig. 7 is isolation drive power circuit；
Fig. 8 is DC-bus voltage sampling circuit；
Fig. 9 is output current sampling circuit；
Figure 10 is line voltage sample circuit；
Figure 11 is current foldback circuit；
Figure 12 is the failure mechanism that three-level inverter is likely to occur；
Figure 13 is DSP control system structural block diagram；
Figure 14 is signal conditioning circuit；
Figure 15 is that the pwm signal of A phase bridge arm switching tube distributes.
Specific embodiment
Illustrate the embodiment of the present invention below with reference to accompanying drawings.In an attached drawing of the invention or a kind of embodiment
The elements and features of description can be combined with elements and features shown in one or more other attached drawings or embodiment.
It should be noted that for purposes of clarity, unrelated to the invention, those of ordinary skill in the art have been omitted in attached drawing and explanation
The expression and description of the component and processing known.
The overall structure block diagram of the three-phase tri-level photovoltaic combining inverter of the application is as shown in Figure 1, entire hardware platform
By main power amplifier board, driving plate, isolation drive power panel, voltage and current sampling plate, DSP control system composition.Three level are carried out
The type selecting of IGBT module, mounting process and pcb board design；IGBT driving and its power supply design is isolated；Voltage and current sample circuit,
The design of the functional circuits such as current foldback circuit and the reliability of the hardware system and electromagnetic compatibility are studied, and is implemented on tool
During the design and pcb board of body circuit are drawn.
Wherein, isolation drive power panel is inserted in driving plate as four driving IC in driving plate board connector by plate
Power supply, then driving plate is inserted on main power amplifier board board connector by plate drives each IGBT module again, and main power amplifier board is through electricity
It connect after sense filter with voltage and current sampling plate, in addition to network voltage on sampling plate, outside the sample circuit of grid-connected current, also wraps
Include it is soft open circuit to be pre-charged for the dc-link capacitance on main power amplifier board, DC-bus voltage sampling circuit is adopted respectively
Collect the DC voltage and hardware current foldback circuit of DC bus top and bottom capacitor, grid-connected control relay etc..This
Zhang Chongdian is the design of main circuit and whole in main power amplifier board, driving plate, isolation drive power panel and voltage and current sampling plate
Reliability and EMC Design main points of a system etc..
1, the design of main power circuit
It include three level IGBT modules on main power amplifier board, dc-link capacitance, the driving such as gate driving resistance is peripheral, in order to
The parasitic inductance of DC bus is reduced, system performance is improved, main power amplifier board uses four layers of pcb board structure, eliminates absorbing circuit,
The plate arrangement layer of four layers of pcb board of main circuit is as follows: walking for what the signals layer and three-phase alternating current of driving interface circuit exported on upper layer
Line, internal planes 1 are direct-flow positive pole plane, and internal planes 2 are used as direct current midpoint plane, and bottom is direct current cathode plane.Direct current input
Terminal, three level IGBT modules, dc-link capacitance are directly connected in each power plane, and the parasitic inductance of DC side is controlled
To a very small extent, the due to voltage spikes on DC bus is effectively reduced in system.
1.1, the selection of IGBT module
The application uses topological structure for the three-level inverter of diode clamp formula, as shown in Figure 2.To reduce stray electrical
Sense, inverter bridge use modularized design, design power 10kW.DC bus-bar voltage is 600V, in each bridge arm, average each master
The forward blocking voltage that switching tube is born is the half of DC bus-bar voltage, considers at least twice allowance, selects three level moulds
The voltage rating of block main switch is 650V, and the application chooses three level of F3L75R07W2E3_B11 type of Infineon company
IGBT power module.
The module is encapsulated using EasyPACK2B type, is integrated with a complete tri- level block bridge arm of 75A in the module,
In addition, the module is also integrated with a NTC thermistor in inside, it can be used for the temperature detection design of module.
The module can be used crimp technology and carry out unleaded installation, this makes installation procedure very succinct, and crimp weldering
It is compatible with soldering, crimping installation cannot be being carried out after removing using the module of crimping installation, but can install by soldering.This Shen
The main power amplifier board that please be designed installs IGBT module using crimp technology.
The IGBT module provides auxiliary emitter electrode terminal, ideal connection type may be implemented, it is ensured that IGBT high
Speed switch.Power supply terminal is in parallel by multiple terminals, it is ensured that obtains nominal rated current, while being also beneficial to reduce stray inductance
With PCB temperature rise.
1.2, the selection of dc-link capacitance
It to be powered on container in inverter input terminal, for absorbing ripple current, support DC bus-bar voltage.With aluminium electroloysis electricity
Based on appearance, but alminium electrolytic condenser can only absorb low-frequency ripple electric current, and helpless to high frequency ripple, at this moment increase noninductive suction
Capacitor is received, its main feature is that high frequency characteristics is good.The quality of electrolytic capacitor is to determine the key point of photovoltaic combining inverter reliability,
Dc-link capacitance in photovoltaic combining inverter will meet following features: high voltage withstanding, high resistance to ripple ability, service life are long.This
Application uses 680 μ F/400V alminium electrolytic condensers of EPCOS company, and two strings two and rear pressure resistance are 800V, and equivalent capacitance is 680 μ F.
2, the design of driving circuit
Since each bridge arm (module) needs the driving of four tunnels, need using the driving suitable for selected three level IGBT module
The peripheral assembly of circuit design, driving chip should lack as far as possible, guarantee lesser PCB size.The protection that driving circuit has
Function such as under-voltage locking and short-circuit protection etc. will match with three level IGBT modules.Typical IGBT drive circuit should have simultaneously
There are input, the output signal function of isolation, and requires signal in driving circuit without transmission delay or delay very little, the application
The driving chip ACPL-332J of selection can easily meet these requirements.
ACPL-332J is a advanced with 2.5A peak-peak output electric current, easy-to-use intelligent door driving light
Coupling, its integrated function include desaturation detection, under-voltage locking, IGBT soft switching, the error feedback output of isolation and active rice
Clamper is strangled, this makes the design of driving circuit very flexibly succinct.Its main feature is as follows:
(1) AIGaAsLED is included, power stage output end is directly coupled to by optics, saves buffer, in entire temperature
In range, maximum traffic delay 250ns, maximum pulse width distortion is only 100ns；
(2) active Miller clamper function is integrated；
(3) open collector FAULT signal is fed back；
(4) FAULT signal can be resetted by pwm signal (rising edge) after the failure occurred；
(5) SO-16 patch encapsulates；
(6) it is minimum 50KV/us, Vcm=1500V that common-mode voltage, which inhibits (CMR),；
(7) 15~30V of wide scope power supply Vcc range, supply current Iccmax < 5mA.
The driver circuit schematic diagram of the application design is as shown in Figure 3, Figure 4, and the 5V that 332J input side needs is by driving plate plate
The 5V power supply power supply of load, the power supply use ZSR500G power supply chip, main electricity 12V are switched to 5V.The side of two 0.1uF
Road capacitor can provide required transient current in switch conversion, and open collector FAULT exports the pull-up resistor for meeting a 2K2
With the filtering ceramic disc capacitor of a 1000pF.The PWM input side for working normally lower 332J controls driving by the electric current IF for flowing through LED
Export Vout.By R102 and R103, the PWM input signal and driving output Vout that amplitude is 12V are inverse relationship.
The protection function of under-voltage locking and IGBT soft switching is integrated in the ACPL-332J driving optocoupler selected in driving circuit
Can, in chip power up, under-voltage locking unit (UVLO) in 332J, which can be dragged down by will export pressure, prevents IGBT
Gate drive voltage it is insufficient because IGBT can work in linear zone when driving voltage deficiency, IGBT power consumption is caused sharply to increase
Add, when the output of driving is high, DESAT (VCE) protection of 332J can monitor the both ends C, E pressure drop of IGBT, when VCE is more than valve
When value, illustrate that short trouble has occurred, 332J can carry out IGBT " soft switching " operation, i.e., driving signal is slow is down to zero, reduce
Current changing rate.As it can be seen that the under-voltage locking and IGBT soft switching of 332J are cooperated to protect IGBT.It is worth noting that
The FAULT signal of 332J automatically resets, and when IGBT soft switching protection act, 332J can feed back a low effective failure letter
Number, after notifying digital processing unit to have short trouble, DSP judgement to break down, PWM wave should be blocked immediately.It is defeated again
PWM wave will be such that FAULT signal resets out.The protection signal sequence of 332J is as shown in Figure 5.
The design of driving circuit IGBT short-circuit protection and two-level inverter are different in three-level inverter, one
The Vce detection protection of 2 inner tubes must shield in a three level bridge arm, and only need to two outer tubes be carried out with short-circuit protection, former
Because being, when two inner tubes simultaneously turn on, that is, export zero level, due to the clamping action of diode, two inner tube both ends electricity
Pressure is zero, will not occur straight-through and short-circuit, and more important point is, if the driving of inner tube has a short-circuit protection, an inner tube because
Protection act and be first turned off, it would be possible to cause entire DC bus-bar voltage to be added on an outer tube, IGBT caused to damage because of over-voltage
It is bad.
So the DESET pin of inner tube driving optocoupler 332J is ground connection in the drive module of a bridge arm, to shield
Short-circuit protection, for driving the driving FAULT signal of two outer tubes on the one hand intuitively to show fault bit by LED circuit respectively
It sets, on the other hand exports after ULN2003 chip to rear class.ULN2003 has two o'clock effect herein: (1) through ULN2003 after, letter
Number amplitude increases, anti-interference ability enhancing；(2) ULN2003 is equivalent to NOT gate, is convenient for late-class circuit to pass through ULN2003 after reverse phase
By six road fault-signals of three drive modules " mutually with ".When working properly, six road FLT signals are low level, 2003
Output DR_FLT is height, and when any FLT signal is high, 2003 output DR_FLT is low, expression driving protection act.
Currently, guarantee IGBT safe shutdown using negative grid voltage in 100A use above, for cost consideration,
For the considerations of reducing cost, the list using 15V/0V is more likely in middle low power (100A or less) grade power inverter
Polarity power replaces bipolar power supply+15V/-9V.But the major issue faced is posted caused by IGBT miller capacitance
Raw conducting phenomenon.Illustrate parasitic turn-on phenomenon with half-bridge circuit, as shown in fig. 6, S2 pipe both ends will appear very when opening S1
High dVce/dt.At this moment the interior of parasitic miller capacitance Ccg of the electric current along S2 pipe, driving resistance Rg and driving IC is had
It is flowed through in the circuit that resistance Rdriver is formed, current path is as shown in fig. 7, the electric current can be estimated by following formula.
Pressure drop on the current causing resistance will generate parasitism if this voltage is more than IGBT gate drive voltage
Conducting.332J has the function of active Miller clamper, effectively inhibits the parasitic turn-on phenomenon under high dV/dt environment, Miller clamper
It can be effectively reduced the pressure drop as caused by Miller electric current, turn off IGBT, In so as to which negative grid voltage need not be used
During IGBT is turned off, 332J can detect grid voltage, be clamped when grid voltage reaches threshold values, and parasitic turn-on phenomenon is prevented
Generation.
When driving the electricity shortage of IC, the shutdown timing of all IGBT is correct, that is to say, that ensure that two outer tubes are wanted
Be first turned off, the way of the application be guarantee to for driving IC power 4 road isolated power supplies export voltage be it is almost the same, so
It has connected in the secondary side energization pins of the driving IC of top tube and down tube respectively afterwards the diode of a high conduction voltage drop.It is equivalent to
An additional pressure drop is provided in under-voltage fault, it is ensured that the driving IC close to the IGBT of DC bus first carries out under-voltage locking
Movement, i.e., two outer tubes are first turned off.
Stable power supply is the basis that IGBT is worked normally, in three-level inverter, the driving of each three level block
Plate needs 4 road isolated power supplies to power for it, arranges two groups of identical power circuits on the isolation drive power panel of the application design,
Every group of power circuit generates two-way isolated power supply, powers for the driving plate of each module.Drive power circuit such as Fig. 7 institute of IC
Show.
The power circuit is semi-bridge type DC-DC conversion circuit, and strong antijamming capability, secondary side is without filter inductance, input impedance
Low, in the driving power supply for needing big peak current output, electric power output voltage still can be more stable.
3, sampling and protecting circuit designed
(1) DC-bus voltage sampling circuit
In order to be monitored and provided in real time overvoltage protection to DC bus lateral capacitance neutral balance situation, it is right respectively to need
Two lateral capacitance of DC bus carries out voltage sample.The sample circuit of DC bus-bar voltage is in series by multiple 1% precision resistances
Bleeder circuit and the difference channel composition that constitutes of high-operational amplifier TL074, upside dc bus sample circuit is as shown in Figure 8.
The forward and reverse end of OP07 all concatenates the 1/8W resistance that 8 resistance values are 220K.In this way, AD is adopted when DC bus-bar voltage is 600V
The voltage of the upper end dc-link capacitance of collection are as follows:
Meet the requirement of 0~3V of AD analog input requirement, the so more resistance series connection of use is from realization strong and weak electricity
From the point of view of the power that isolation and resistance can bear.
(2) grid-connected current sample circuit
Current sensor the multiple functions such as shows in feedback control, system protection, the parameter for realizing photovoltaic combining inverter
In play extremely important effect, so its accuracy and stability must be focused on when selecting current transformer.The application uses
The 4644-X300 type current sensor of German VAC company samples grid-connected current, and the current transformer is in traditional closed loop
On the basis of Hall current sensor, traditional Hall plate is replaced using the amorphous soft magnet piece with patented technology, to obtain
Brilliant performance, compared with conventional Hall current sensor, it have accuracy height, good temp characteristic, corresponding speed fastly, frequency band
The advantages that range is wide.Sensor use ± 15V the dual power supply is the electric current way of output, so its output signal needs elder generation
The conversion of one voltage of electric current is carried out by sampling resistor, being then converted into through impedance matching, ratio, voltage increase, filtering can be by DSP
The signal received.It is as shown in Figure 9 to export current sampling circuit.
5 pairs of input terminals of the current sensor can there are many connection types, and then different input and output may be implemented
Than measurement electric current 1A to 25A is adjustable, and the application is used in parallel by 5 pairs of input terminals, as shown in figure 9, to obtain input and output electricity
Stream ratio is 1000:1, i.e., when input terminal flows through 25A electric current, output current signal 25mA, sampling resistor R1 value is 100
Europe, such 25A current versus voltage are 2.5V, peak-to-peak value 5V.Sampling resistor rear class connects level-one by the single amplifier OP07 of high-precision
The voltage follower of composition improves input impedance and carrying load ability, that is, plays the role of impedance matching.
(3) line voltage sample circuit
Gird-connected inverter realize cutting-in control another important link be network voltage sampling, voltage transformer it is accurate
Degree and stability are also particularly important.The application uses the TV19G type voltage transformer of the Dechang Yao Hua company, which is vacuum
Epoxy is filling, is directly welded in PCB circuit board, totally-enclosed, and dielectric strength reaches 10KV, and uses slope film alloy-iron core, line
Property degree be better than 0.2%.Equally, which is also the electric current way of output, following stage processing and output current sampling circuit
It is similar.Line voltage sample circuit is as shown in Figure 10.
The specified input current of the voltage transformer is 5mA, and power grid three-phase voltage rating is AC380V, considers 10% wave
Dynamic, network voltage maximum amplitude is about 600V, then it is 120 kilo-ohms that input side current-limiting resistance, which selects resistance value, 1% essence that power is 3W
Resistance is spent, because DSP, which needs to sample AD, carries out zero correction, controls three voltage transformers with a three-phase electrical relay
With the on-off of network voltage, when carrying out AD timing, relay normally closed contact is closed, and the input terminal of three voltage transformers is mutual
It is shorted, i.e., input is zero；When acquiring network voltage, relay normally open contact closure, the input terminal and power grid of voltage transformer
Connection.
4, the design of current foldback circuit
In addition to the defencive function that driving circuit integrates, this system is also provided with the hardware overcurrent protection of output electric current, circuit
As shown in figure 11, No. three sample circuits output representative output electric current voltage signal after three-phase uncontrollable rectifier with I_REF
It is compared.When signal after rectification is less than I_REF, comparator output is+15V, conversely, comparator output is -15V, this
When optocoupler 2561L-1 LEDs ON, and then receiving end triode is connected, and XINT becomes low electricity from high level 3.3V
It is flat.If current foldback circuit fails, and short trouble occurs, i.e., when DR_FLT becomes low, XINT can also become low level.
5, the reliability and EMC Design of system
(1) timing of same bridge arm IGBT shutdown
For common two-level inverter, when shutdown is two switching tubes simultaneously turned off on each bridge arm, but in three electricity
When flat inverter carries out power-off operation, if still may result in serious problems using this way.With as shown in figure 12
Situation come illustrate power-off operation there are the problem of, at this time the switch state of the bridge arm be [1100], current direction be outflow inversion
Device.
When carrying out power-off operation, if the driving signal of T1 and T2 is lower by height to turn off the two switching tubes simultaneously,
Then it is likely used only to occur T2 because of the asymmetry of switching tube parameter itself and have been switched off, the state that T1 is still connected, and
At this moment free wheeling path is anti-paralleled diode D4 and D3, and DC bus-bar voltage entire in this way can be added in switch transistor T 2, makes this
Switching tube fails because of over-voltage.So, to ensure safety, being wanted before turning off inner tube when three-level inverter carries out power-off operation
Guarantee that outer tube has completely turned off.Therefore, inner tube is not provided with hardware protection in the design protection of three level block driving circuits
(driving circuit directly turns off the switch pipe), while delay process is also carried out in the power-off operation of DSP program, it is ensured that correctly close
Machine timing.
(2) current-carrying capability of high-power pcb board lines
Copper conductor figure on PCB can generate heat when the current flows since there are resistance for itself, if electric current is in milliampere grade
Or when following, heating problem be can be ignored, but cannot be ignored when there is high current (hundred milliamperes of grades or more) to pass through,
Heat dissipation problem solution is bad, necessarily causes the raising of temperature-sensitive device temperature in circuit, leads to the drift of circuit operating point, performance refers to
Mark reduces, and influences the reliability and stability of entire circuit.When the electric current flowed through on PCB is seriously more than the current-carrying energy of conductor lines
When power, conducting bar temperature can be made to rise rapidly, when temperature is more than 85 degree, PCB insulating materials starts to turn to be yellow, and electric current continues to flow through,
Last lines fusing.
The photovoltaic combining inverter power of the application design is 10KW, and output rated current is 15A, and so big electric current is wanted
It circulates on PCB, it has to be noted that the width of corresponding cabling makes temperature rise control in reasonable range, printed circuit board current-carrying energy
Power is codetermined by the temperature rise that trace width, copper film thickness and PCB allow.
(3) in pcb board decoupling capacitor and storage capacitor effect
The element of period switching must carry out RF and move back idol, and method is proximate to power elements pin placement high frequency and moves back even capacitor
(usually low-capacitance ceramic disc capacitor).Otherwise switching energy impact can be circulated into power supply and ground connection distribution system, and with common mode
Or the form of differential mode travels to circuit other parts, causes interference.
The direct current supply of element not only needs to place high frequency nearby and moves back even capacitor, but also will be in some positions in whole PCB
Placing storage capacitor reduces the influence of power distribution network such as electrolytic capacitor or tantalum capacitor.The logic of each element on pcb board
State can cause the fluctuation of supply current when switching over, this fluctuation will lead to power supply and drop and influence other elements, very
To cisco unity malfunction, storage capacitor is circuit energy reserve, and voltage and current is made to be maintained at best stabilized state.
Storage capacitor is placed according to the following rules: near the power supply interface of PCB；Near power output terminal；Greatly
Near power component；Near the farther away power elements of power input.
(4) the power supply design of system
The hardware system of photovoltaic combining inverter is made of multiple circuit boards, and a variety of direct currents are required on each circuit board
Source, each road power supply have different stability requirements, even need the different pcb boards of identical DC voltage, the electricity needed
It is also not identical to flow size, using the power source design of single module multiple-channel output, is difficult to meet this requirement, the road modular power source Zhong Ge is defeated
There are cross jammings between out, can not guarantee the stability of each road power supply output simultaneously.The application uses distributed DC power system
System, the power-supply system are made of an AC/DC Switching Power Supply (exchange leading portion power module) and multiple DC/DC conversion modules, hand over
Exchange is converted to the DC voltage of 12V, the bus as distributed DC power by stream leading portion.Dc bus is connected to inversion
On the different pcb boards of device hardware system, then the different DC voltages that each functional circuit needs are generated by onboard DC/DC module,
Such as 3.3V, ± 15V, 5V etc..
Distributed DC power system suitability is strong, has fine reliability and Electro Magnetic Compatibility, each section electricity of system
Source is independent, and partial power is smaller, not high to the power quality requirements of dc bus, and the DC/DC module of rear end ensure that output electricity
The stability of pressure, each subsystem are powered on the spot, and power supply loop is small, and the influence of line impedance is small, strong antijamming capability, and each power supply is whole
The current fluctuation at end will not influence each other, and not have rush of current interference between each other.
6, the DSP control system for being suitable for three-phase tri-level photovoltaic combining inverter is devised
The DSP control system is using the TMS320F28335 of TI company as control core, and control system is by DSP28335 core
Plate and bottom plate composition, the pinboard (AdapterBoard) of bottom plate functioned as between control core and inverter are turning
The human-computer interaction interface interface that signal conditioning circuit and PWM interface circuit and system are devised on fishplate bar, such as serial communication, key
Disk, display etc..It is required according to the dead zone of 12 road pwm signal features of three-phase tri-level inverter and three level bridge arms, to DSP
The pwm signal of output has carried out reasonable configuration.
6.1, TMS320F28335 core board
TMS320F28335 be 32 floating point number signal processors, instruction cycle 6.67ns, dominant frequency 150MHz,
The abbreviated functional description of DSP28335 relevant to the application is as follows:
1. different by task manager (EV) generation pwm signal from 281X series DSP, 28335 series use enhanced PWM
Module (ePWM) generates pwm signal, and PWM output function of the ePWM module relative to EV is greatly improved, and 28335 have 6
A ePWM module, can produce 6 pairs of independent complementary PWM signals, and each ePWM module can be independently programmable use.
2. being internally integrated one 12 A/D converters, it is logical that two multidiameter option switch (MUX) expand 16 inputs
Road, tool provide internal reference voltage and external reference voltage input pin, input simulation there are two sampling and keeping (S/H) device
Voltage range: 0~3V, conversion rate are up to 80ns.
3.8 external interrupts, and the external interrupt pin unlike DSP281X series is not fixed, and can flexibly be divided
It is assigned to GPIO0~GPIO63.
The application selects 28335 minimum system plates of Yan Xu company as core using TMS320F28335 as control core
Plate, the core board are six veneer structures, and strong antijamming capability, reliability and stability is high, and are that DSP extends a structure and is
The high speed Flash of 512*16 and a 8M capacity, the low-power consumption high-speed SRAM that structure is 512*16 word lengths；The core board
It is DSP using specially designed dual output voltage source managing chip that power supply, which uses TI company, keeps DSP powered stable reliable；
The 28335 functional pin of institute draws plate interface by plate, carries out detailed programs exploitation convenient for design bottom plate.
6.2, the pinboard design of DSP28335 core board
In the application, the bottom plate of core board is the pinboard connected between DSP core core and inverter other hardware systems
(AdapterBoard), major function includes signal condition, PWM output, SCI serial communication, in-circuit emulation of DSP etc., DSP
The overall structure of control system is as shown in figure 13.
(1) analog signal conditioner interface circuit
The voltage signal that the AD of DSP28335 allows to input is 0 unipolar signal for arriving 3.0V, line voltage sample circuit
Signal with output current sampling circuit output is AC signal and peak-to-peak value is greater than 3V, to carry out ratio to these signals
AD can be sent into after transformation and voltage increase to be sampled.Signal conditioning circuit is as shown in figure 14, and prime amplifier composition becomes
Circuit is changed, by the peak-to-peak value of input signal, is adjusted to 3V hereinafter, rear class amplifier composition add circuit, prime amplifier is exported
Signal boost 1.5V, makes output signal become unipolar signal, to avoid inputting negative voltage to AD.To prevent signal amplitude from overflowing
Out, a clamp circuit being made of two low conduction voltage drop diodes is added in the output end of sample circuit, clamper exists respectively
0V and 3V, further protects AD.
(2) pwm signal interface
It is sent by the winding displacement of certain length to the main power amplifier board of inverter in view of pwm signal is DSP control panel, to improve
Anti-interference ability, the ULN2003 chip that the pwm signal that the amplitude of DSP output is 3.3V first passes through DSP bottom plate export again, main function
Rate circuit drives plate Shang Zaiduige road pwm signal adds pull-up resistor, and the pwm signal amplitude transmitted on winding displacement in this way is 12V, makes
Signal reliable transmission in the environment of high electromagnetic noise, improves the interference free performance of system.Due to 2003 have inverting function,
So the input of IGBT drive circuit and gate driving output are configured to rp mode, the pwm signal and driving circuit of such DSP
Gate driving output be same phase relation.
(3) other function interface
The DSP control panel bottom plate of the application design is on the basis of the DSP28335 of Yan Xu company practical plate to adapt to three
Level hardware platform courses demand improves, and remains some utility function interfaces of master, such as serial communication interface
(can connect touch screen), SD memory card interface are defeated with the CPLD interfaces such as LCD, keyboard expanded and some unused DSP pins
Entering/output interface, these interfaces can be used for the machine Interaction Interface Design of three-level inverter and the functions expanding of system,
Allowance is left for further deeply developing for whole system.
6.3, the PWM of DSP exports configuration
Three-level inverter needs 12 road pwm signals, wherein there is 6 tunnels to be independent from each other, 28335 have 6 it is mutually indepedent
EPWM module, can produce 6 pairs of complementary pwm signals, can be used as just 12 tunnel of three-level inverter driving PWM letter
Number.The only interruption of enabled ePWM1, SVPWM algorithm routine is write in the interruption and obtains six ePWM modules in 6 ePWM modules
Comparand register fiducial value, the update condition of the comparand register of ePWM1 to ePWM6 is identical, by taking A phase bridge arm as an example, PWM
The distribution of signal is as shown in figure 15, and as seen from the figure, PWM1A drives 1 pipe of A phase bridge arm, and PWM1B drives 3 pipes of A phase bridge arm,
PWM2A drives 2 pipes of A phase bridge arm, and PWM2B drives 4 pipes of A phase bridge arm, and the rest may be inferred for B, C phase bridge arm.
In two-level inverter, to avoid two power switch tubes for being connected on same bridge arm straight-through, a pair of of band is needed
The conducting period for having the pwm signal of " dead time (dead-time) " to control the two devices correctly to ensure two devices
It is not overlapped centainly.It to be inserted into a time interval between the shutdown and the conducting of another switching tube of a switching tube, this is
Dead time.This section of delay is determined by the switching characteristic and load characteristic of switching tube.The purpose for designing dead zone unit is any
In the case of, it is ensured that the phase of opening of upper arm device and lower arm device is not overlapped.It is equally also required to be arranged in three-level inverter
Dead zone.
The output of three-level inverter is respectively there are three types of state: 1 [1100], 0 [0110], -1 [0011], output level
Change between 1,0, -1, and is not in 1 to -1 or -1 to 1 step, the transition between only 1 and 0 or -1 and 0.Such as 1
It [1100], will between 1 pipe and 2 pipes if 3 pipes have been turned on when 1 pipe does not complete switch off also during becoming 0 [0110]
Short circuit due to straight-through, and entire DC bus-bar voltage can be added on 4 pipes, and 4 pipes are damaged because of over-voltage.So to be carried out to DSP
The dead time, dead time is set by the corresponding counts register of Dead-band (DB) module in ePWM module in 28335
It sets, the count value of register is determined by dead time size and switching frequency.
Although being had been disclosed above by the description to specific embodiments of the present invention to the present invention, it answers
The understanding, above-mentioned all embodiments and example are exemplary, and not restrictive.Those skilled in the art can be in institute
Design is to various modifications of the invention, improvement or equivalent in attached spirit and scope of the claims.These modification, improve or
Person's equivalent should also be as being to be considered as included in protection scope of the present invention.
Claims (8)
1. a kind of control system for three-phase tri-level photovoltaic combining inverter, it is characterised in that: the system includes main power
Plate, driving plate, isolation drive power panel, voltage and current sampling plate and DSP control system composition；Driving plate is equipped with driving electricity
Road；
Wherein, isolation drive power panel is inserted in driving plate board connector by plate, is that four driving IC in driving plate are supplied
Electricity, then driving plate is inserted on main power amplifier board board connector by plate drives each IGBT module again, and main power amplifier board is through inductance
Connect after filter with voltage and current sampling plate, sampling plate be equipped with acquisition network voltage and grid-connected current sample circuit, with
And it is soft open circuit, the soft circuit that opens is for being pre-charged the dc-link capacitance on main power amplifier board, DC bus-bar voltage sampling
Circuit acquires the DC voltage of DC bus top and bottom capacitor respectively.
2. control system according to claim 1, it is characterised in that: include three level IGBT moulds on the main power amplifier board
Block, dc-link capacitance and gate driving resistance.
3. control system according to claim 2, it is characterised in that: the main power amplifier board uses four layers of pcb board structure, plate
Arrangement layer is as follows: cabling of the upper layer for signals layer and the three-phase alternating current output of driving interface circuit, internal planes 1 are direct-flow positive pole
Plane, internal planes 2 are used as direct current midpoint plane, and bottom is direct current cathode plane；
DC input terminal, three level IGBT modules, dc-link capacitance are directly connected in each power plane.
4. control system according to claim 2, it is characterised in that: it is public that the three level IGBT module chooses Infineon
The three level IGBT power module of F3L75R07W2E3_B11 type of department is realized.
5. control system according to claim 1, it is characterised in that: the selection EPCOS company of the dc-link capacitance
680 μ F/400V alminium electrolytic condensers.
6. control system according to claim 1, it is characterised in that: the driving circuit uses chip model for ACPL-
The driving chip of 332J is realized.
7. control system according to claim 1, it is characterised in that: the isolation drive power panel uses distributed DC
Power-supply system realizes that the power-supply system is made of an AC/DC Switching Power Supply and multiple DC/DC conversion modules, and exchange leading portion will
Exchange is converted to the DC voltage of 12V, the bus as distributed DC power；Dc bus is connected to inverter hardware system
On the different pcb boards of system, then the different DC voltages that each functional circuit needs are generated by onboard DC/DC module.
8. control system according to claim 1, it is characterised in that: the DSP control system is with TI company
TMS320F28335 is control core, is made of DSP28335 core board and bottom plate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910716888.1A CN110474366A (en) | 2019-08-05 | 2019-08-05 | A kind of control system for three-phase tri-level photovoltaic combining inverter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910716888.1A CN110474366A (en) | 2019-08-05 | 2019-08-05 | A kind of control system for three-phase tri-level photovoltaic combining inverter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110474366A true CN110474366A (en) | 2019-11-19 |
Family
ID=68509375
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910716888.1A Pending CN110474366A (en) | 2019-08-05 | 2019-08-05 | A kind of control system for three-phase tri-level photovoltaic combining inverter |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110474366A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110854935A (en) * | 2019-12-08 | 2020-02-28 | 国网山西省电力公司电力科学研究院 | Photovoltaic power station active power automatic control method with sample plate inverter |
| CN111342692A (en) * | 2019-12-24 | 2020-06-26 | 兰州飞行控制有限责任公司 | Low-power three-phase inverter power circuit |
| CN112152489A (en) * | 2020-09-23 | 2020-12-29 | 南京信息工程大学 | High-low voltage direct current dual-output integrated three-phase PWM rectifier converter and control method |
| CN112234702A (en) * | 2020-09-30 | 2021-01-15 | 漳州科华技术有限责任公司 | Power supply device and UPS |
| CN113013919A (en) * | 2021-03-04 | 2021-06-22 | 河北工业大学 | Symmetrical double-mode photovoltaic inverter device |
-
2019
- 2019-08-05 CN CN201910716888.1A patent/CN110474366A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110854935A (en) * | 2019-12-08 | 2020-02-28 | 国网山西省电力公司电力科学研究院 | Photovoltaic power station active power automatic control method with sample plate inverter |
| CN110854935B (en) * | 2019-12-08 | 2022-07-12 | 国网山西省电力公司电力科学研究院 | Photovoltaic power station active power automatic control method with sample plate inverter |
| CN111342692A (en) * | 2019-12-24 | 2020-06-26 | 兰州飞行控制有限责任公司 | Low-power three-phase inverter power circuit |
| CN111342692B (en) * | 2019-12-24 | 2023-09-22 | 兰州飞行控制有限责任公司 | Low-power three-phase inverter circuit |
| CN112152489A (en) * | 2020-09-23 | 2020-12-29 | 南京信息工程大学 | High-low voltage direct current dual-output integrated three-phase PWM rectifier converter and control method |
| CN112234702A (en) * | 2020-09-30 | 2021-01-15 | 漳州科华技术有限责任公司 | Power supply device and UPS |
| CN113013919A (en) * | 2021-03-04 | 2021-06-22 | 河北工业大学 | Symmetrical double-mode photovoltaic inverter device |
| CN113013919B (en) * | 2021-03-04 | 2023-06-30 | 河北工业大学 | Symmetrical dual-mode photovoltaic inverter device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110474366A (en) | A kind of control system for three-phase tri-level photovoltaic combining inverter | |
| CN203405559U (en) | Electronic load of electric energy feedback type | |
| CN104052079A (en) | Electric energy feedback type electronic load | |
| CN104578865A (en) | Tri-level four-leg T-shaped fault-tolerant converter and control method thereof | |
| CN106655853A (en) | Three-level inverter | |
| CN105743378B (en) | A kind of T-shaped three-level inverter parallel system and its decoupling control method | |
| CN207518331U (en) | A kind of onboard charger based on LLC half bridge resonant | |
| CN103722277B (en) | A kind of DC arc welding machine | |
| CN105763162A (en) | Power Amplifiers Coupled In Series | |
| CN203352454U (en) | Voltage-type high-frequency constant current source | |
| CN102510276A (en) | Big-power module high-frequency driver with non-neural advance mechanism | |
| CN110401354B (en) | High-power GaN half-bridge LLC charging module for new energy automobile | |
| CN105242149A (en) | IGCT phase module circuit with inductor voltage state detection | |
| CN206024154U (en) | LED light modulating devices and LED drive power | |
| CN2834102Y (en) | X-ray tube control circuit for X-ray instrument | |
| CN112953235A (en) | High-power isolated multi-module parallel charging power supply for super-capacitor bus | |
| CN105978372A (en) | Topological circuit, half-bridge topological circuit and three-phase full-bridge topological circuit | |
| CN107911033B (en) | Design method for optimizing total stray inductance of main circuit and locomotive variable-current power unit | |
| CN109873570A (en) | Three level T font topological structures of one kind and single-phase inverter and three-phase inverter | |
| CN114113861A (en) | Load current adjustable flexible straight half-bridge module short circuit test loop and test method | |
| CN209709969U (en) | Three level T font topological structures of one kind and single-phase inverter and three-phase inverter | |
| CN104270890A (en) | Electric-system universal electric quantity signal protective board based on modular design | |
| CN201002166Y (en) | High-frequency IGBT inversion type hand welding power source | |
| CN103795279B (en) | Time difference control power supply transformation circuit | |
| CN208623560U (en) | A kind of high-performance electric source circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| WD01 | Invention patent application deemed withdrawn after publication | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20191119 |