CN103904638B - Direct-current distributed load system based on three-port converter and control method thereof - Google Patents
Direct-current distributed load system based on three-port converter and control method thereof Download PDFInfo
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- CN103904638B CN103904638B CN201410154890.1A CN201410154890A CN103904638B CN 103904638 B CN103904638 B CN 103904638B CN 201410154890 A CN201410154890 A CN 201410154890A CN 103904638 B CN103904638 B CN 103904638B
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Abstract
The invention discloses a direct-current distributed load system based on a three-port converter and a control method thereof and belongs to the field of power electronics conversion and distributed load systems. The system comprises a direct-current input power supply (10), a power conversion unit (20) composed of N three-port sub-converters, and a load (30) composed of N sub-loads, wherein N is a natural number larger than 1, the output end of the direct-current input power supply serves as an input end voltage bus of the system, the input end of each three-port sub-converter is connected to the input end voltage bus, the energy storage end of each three-port sub-converter is connected to an energy storage end voltage bus, and the output end of each three-port sub-converter is connected with a corresponding sub-load in series. According to the system, a hybrid power control strategy that energy storage end current sharing is conducted during charging of an energy storage device and input end power is distributed according to the intensity of output power during discharging of the energy storage device is adopted based on the charging and discharging states of the energy storage device, and stable and reliable operation of the system is achieved.
Description
Technical field
The present invention relates to a kind of direct current distributed terminator system based on three Port Translation devices and its control method, belong to electricity
The conversion of power electronics and distributed terminator system regions.
Background technology
Increasingly serious with energy crisis and problem of environmental pollution, new forms of energy such as solar energy, wind energy, fuel cell and can be again
The development and utilization of the raw energy obtains more and more widely paying close attention to, and grid-connected power generation system has become countries in the world concern and studied
Focus.In same grid-connected power generation system, may there are multiple same natures or multiple of different nature distributed
Load, in order to meet the power demands of distributed terminator simultaneously, common solution is using two-stage type power conversion system,
First pass through one-level dc/dc changer and new forms of energy are changed into direct current output, and be output as with this dc/dc changer public straight
Stream bus, then concatenates a dc/dc changer respectively and is individually powered to each distributed terminator.
Further, since the generation of electricity by new energy device such as solaode to there is supply of electric power unstable, discontinuous and with environment
The shortcomings of condition changes, need be equipped with energy storage device with provide peak power and reclaim excess energy it is ensured that power supply seriality
And reliability.Therefore, also need to two-way dc/dc changer between energy storage device and common DC bus to connect, to realize work(
Rate transmitted in both directions.
However, when adopting said system structure, power is from input source to load, from input source to energy storage device with from energy storage
When device transmits under three kinds of situations such as load, it is required to convert through two stage power, thus reducing the whole efficiency of system.
Content of the invention
Goal of the invention:
The present invention is directed to the deficiencies in the prior art, provides a kind of direct current distributed terminator system based on three Port Translation devices
And its control method.
Technical scheme:
The present invention adopts the following technical scheme that for achieving the above object
The direct current distributed terminator system based on three Port Translation devices of the present invention, becomes including direct-current input power supplying, power
Change unit and load, described power conversion unit includes n sub three Port Translation devices, described load includes n son load, n is
Natural number more than 1, the output of direct-current input power supplying as system input voltage bus, every height three Port Translation device defeated
Enter end and be connected to input terminal voltage bus, the energy storage end of every height three Port Translation device is connected to energy storage terminal voltage bus,
The outfan of every height three Port Translation device all concatenates a son load.
Described direct-current input power supplying is direct voltage source or renewable energy source current, can be that single power supply can also be by many
Individual power supply connection in series-parallel is constituted.
Described three Port Translation devices are isolated form three Port Translation device or non-isolation type three Port Translation device.
Described three Port Translation devices include a DC voltage input end, an outfan and an energy storage end, wherein store up
Can end be bidirectional power port, outfan is unidirectional power port or bidirectional power port.
Based on the control method of above-mentioned direct current distributed terminator system, the control method phase of all sub three Port Translation devices
It is divided into the following two kinds situation with, its control process:
A., when energy storage device is in charged state, each sub three Port Translation devices adopt the control strategy of energy storage end all stream,
Concrete control process is as follows:
Believed using the meansigma methodss of each sub three Port Translation device energy storage end electric currents or maximum as energy storage end current equalizing bus bar voltage
Number ib_bus, this signal as the Setting signal of each sub three Port Translation device energy storage end electric currents, with each sub three Port Translation device energy storage
End current feedback signal ibObtain both error signals v after the equal throttle regulator in energy storage end is adjustedbcs, this error signal with
Reference voltage vinrefAs the Setting signal of this sub three Port Translation device input terminal voltage after superposition, with this sub three Port Translation device
Input terminal voltage feeds back signal vinObtain both error signals v after input terminal voltage actuator is adjustedc, this error signal
As the control signal of input terminal voltage, it is handed over carrier signal and intercepts drive signal, thus realizing this sub three Port Translation
The control of device；
B., when energy storage device is in discharge condition, each sub three Port Translation devices divide using according to respective output size
Join the control strategy of input power, concrete control process is as follows:
Energy storage end electric current i by each sub three Port Translation devicesbDivided by respective output poCarry out standardization, obtain each
The energy storage end electric current perunit value i of sub three Port Translation devices* b, with the meansigma methodss of each sub three Port Translation device energy storage end electric current perunit values
Or maximum is as energy storage end perunit current equalizing bus bar voltage signal i* b_bus, this signal is as each sub three Port Translation device energy storage ends
The Setting signal of perunit electric current, with each sub three Port Translation device energy storage end perunit current signal i* bThrough energy storage end, perunit electric current is equal
Throttle regulator obtains both error signals v after adjustingbcs, this error signal and reference voltage vinrefAs this son three after superposition
The Setting signal of Port Translation device input terminal voltage, with this sub three Port Translation device input terminal voltage feedback signal vinThrough input
Terminal voltage actuator obtains both error signals v after adjustingc, this error signal as the control signal of input terminal voltage, its
Hand over carrier signal and intercept drive signal, thus realizing the control of this sub three Port Translation device.
The invention has the following beneficial effects:
(1) due to using distributed terminator structure, each output loading end can with independent control, reduce each sub- load it
Between influence each other, meet multiple heterogeneitys or demand load while power；
(2) from direct-current input power supplying to load, from direct-current input power supplying to energy storage device and from energy storage device to load etc.
Power conversion under three kinds of situations is single-stage power conversion, improves the whole efficiency of system；
(3) adopt integrated form three Port Translation device as the basic component units of system, simplify the structure of system, improve
The reliability of system；
(4) when being charged using energy storage device, energy storage end is all flowed, energy storage device divides according to respective output size when discharging
Join the Hybrid Power-Aware control strategy of input power it is ensured that stable, reliability service under different operating modes for the system.
Brief description
Accompanying drawing 1 is the direct current distributed terminator system embodiment structural representation based on three Port Translation devices of the present invention；
Accompanying drawing 2 is the electric operation control circuit figure of sub three Port Translation devices during energy storage device charged state of the present invention；
Accompanying drawing 3 is the electric operation control circuit figure of sub three Port Translation devices during energy storage device discharge condition of the present invention；
Accompanying drawing 4 is that the structure of the direct current distributed terminator system that two three Port Translation devices of embodiments of the invention are constituted is shown
It is intended to；
Accompanying drawing 5 is synchronous rectification formula half-bridge three Port Translation device circuit theory diagrams in the present embodiment；
Experimental result when accompanying drawing 6 normally runs for the present embodiment；
Symbol description in the figures above: 10- direct-current input power supplying；20- power conversion unit；30- loads；vin1～vinn-
1～n sub three Port Translation device input terminal voltages；ib1～ibn- the 1～n sub three Port Translation device energy storage end electric currents；vo1
～von- the 1～n sub three Port Translation device output end voltages；io1～ion- the 1～n sub three Port Translation device outfan electricity
Stream；po1～pon- the 1～n sub three Port Translation device outputs；i* b1～i* bn- the 1～n sub three Port Translation device energy storage
End electric current perunit value；ib_bus- three Port Translation device energy storage end current equalizing bus bar voltages；i* b_bus- three Port Translation device energy storage end perunits
Current equalizing bus bar voltage；vinref1～vinrefn- the 1～n sub three Port Translation device input terminal voltage reference values；Bcs1～bcsn-
The equal throttle regulator in energy storage end of 1～n sub three Port Translation devices；Ivr1～ivrn- 1～n sub three Port Translation devices
Input terminal voltage actuator；vbcs1～vbcsnThe energy storage end equal throttle regulator output voltage of-the 1～n sub three Port Translation devices；
vc1～vcn- the 1～n sub three Port Translation device input control voltages；Pv, pv1, pv2- photovoltaic array；c1、c2- input filter
Ripple electric capacity；q1～q4- switching tube；co- output filter capacitor；lo- output inductor；ro、ro1、ro1- output loading；vo- output
Voltage；io- output current；iin- input current.
Specific embodiment
The invention will be further described below in conjunction with the accompanying drawings.
The direct current distributed terminator system structure based on three Port Translation devices of the embodiment of the present invention is as shown in figure 1, include
Direct-current input power supplying 10, power conversion unit 20 and load 30, wherein: direct-current input power supplying 10 adopts in renewable energy source current
Photovoltaic array, power conversion unit 20 includes n sub three Port Translation devices, and load 30 includes n son and loads, and n is more than 1
Natural number, as system input voltage bus, the input of every height three Port Translation device is all connected with for the output of photovoltaic array
To input terminal voltage bus, the energy storage end of every height three Port Translation device is connected to energy storage terminal voltage bus, every height three end
The outfan of mouth changer all concatenates a son load.
The control method of the direct current distributed terminator system based on above-described embodiment, the control of all sub three Port Translation devices
Method is identical, and its control process is divided into the following two kinds situation:
A., when energy storage device is in charged state, each sub three Port Translation devices adopt the control strategy of energy storage end all stream；
B., when energy storage device is in discharge condition, each sub three Port Translation devices divide using according to respective output size
Join the control strategy of input power.
The Power Control side to the direct current distributed terminator system based on above-described embodiment for the 2～accompanying drawing 3 below in conjunction with the accompanying drawings
Method is made a concrete analysis of.
It is the electric operation control circuit figure of sub three Port Translation devices during energy storage device charged state of the present invention as shown in Figure 2.This enforcement
All flow the current equalizing structure of outer shroud, input terminal voltage internal ring, wherein energy storage end current equalizing bus bar voltage generation side using energy storage end in example
Formula is to average, and flow equalizing ring and Voltage loop are all using pi controller structure.
Taking the control of k-th sub three Port Translation device as a example, its in energy storage device charged state energy storage end is discussed in detail
The detailed process of sharing control.
The producing method of energy storage end current equalizing bus bar voltage be average it may be assumed that
This signal is as the Setting signal of each sub three Port Translation device energy storage end electric currents, three Port Translation devices with k-th
Energy storage end current feedback signal (ibk) obtain both error signals after the equal throttle regulator in energy storage end (bcsk) is adjusted
(vbcsk), this error signal and reference voltage (vinrefk) given as this sub three Port Translation device input terminal voltage after superposition
Signal, with this sub three Port Translation device input terminal voltage feedback signal (vink) adjust through input terminal voltage actuator (ivrk)
Obtain both error signals v afterwardsck, as the control signal of input terminal voltage, it is handed over carrier signal and intercepts this error signal
To drive signal, thus realizing the control of this sub three Port Translation device.
It is the electric operation control circuit figure of sub three Port Translation devices during energy storage device discharge condition of the present invention as shown in Figure 3.This enforcement
The current equalizing structure of outer shroud, input terminal voltage internal ring is all flowed using energy storage end perunit electric current, wherein energy storage end perunit all flows mother in example
Line voltage producing method is to average, and flow equalizing ring and Voltage loop are all using pi controller structure.
Taking the control of k-th sub three Port Translation device as a example, it is discussed in detail in energy storage device discharge condition according to each
Distribute the detailed process of input power from output size.
First the energy storage end electric current of each sub three Port Translation device modules is carried out standardization divided by respective output, obtain
To its energy storage end electric current perunit value:
Then Balance route is carried out to each energy storage end electric current perunit value obtaining, using similar energy storage end sharing control knot
Structure, the producing method of energy storage end perunit current equalizing bus bar voltage be average it may be assumed that
This signal becomes as the Setting signal of each sub three Port Translation device energy storage end perunit electric currents, three ports sub with k-th
The energy storage end electric current perunit value (i of parallel operation module* bk) compare, after the equal throttle regulator of energy storage end perunit electric current (bcsk) is adjusted
Obtain both error signal (vbcsk), this error signal and reference voltage (vinrefk) after superposition as this sub three Port Translation
The Setting signal of device input terminal voltage, with this sub three Port Translation device input terminal voltage feedback signal (vink) through input electricity
Pressure actuator (ivrk) obtains both error signals v after adjustingck, this error signal as the control signal of input terminal voltage,
It is handed over carrier signal and intercepts drive signal, thus realizing the control of this sub three Port Translation device.
A kind of embodiment of the present invention is the direct current distributed terminator system being made up of two three Port Translation devices, wherein stores up
Can be accumulator, load as resistive load, its system structure diagram is as shown in Figure 4 by device.Two son three Port Translation devices
Outfan connect respectively two son load ro1And ro2, input and energy storage end are connected in parallel respectively.
In the present embodiment, each sub three Port Translation devices choose synchronous rectification formula half-bridge three Port Translation device topology, physical circuit
Schematic diagram is as shown in Figure 5.Wherein, q3And q4It is respectively q1And q2Synchronous rectifier, respectively control q1And q2Dutycycle come real
Existing input (energy storage end) and the control of output end voltage.
System structure based on the present invention and control method, experimental result such as Fig. 6 institute in normal operation for the present embodiment
Show.In figure, iin1And iin2It is respectively the input electric current of two son three Port Translation devices, ib1And ib2It is respectively two son three ends
The energy storage end electric current of mouth changer, vo1And vo2It is respectively the output end voltage of two son three Port Translation devices, po1For 1# three end
The outfan power of mouth changer.The watt level of system input is 150w, the outfan power of 2# three Port Translation device
It is fixed as 60w, the outfan power of 1# three Port Translation device changes between 70w-120w.It will be appreciated from fig. 6 that at 1# three end
Before the outfan power of mouth changer increases, system is in battery state of charge, now adopts energy storage end sharing control, has ib1
=ib2, i is had according to power relation input electric currentin1＞ iin2；After the outfan power of 1# three Port Translation device increases, store
Battery is in discharge condition, now according to outfan watt level distribution input power (120w/60w), has iin1=2iin2,
Accumulator terminal electric current also meets similarity relation: i simultaneouslyb1=2ib2；Outfan power in 1# three Port Translation device becomes simultaneously
Change moment, the output end voltage of two son three Port Translation devices is all kept approximately constant the stable power-supplying it is ensured that load end.Real
Test result to show, using system structure and the control method of the present invention, it is possible to achieve the stable, reliability service of system.
Claims (1)
1. a kind of control method of the direct current distributed terminator system based on three Port Translation devices, this system includes direct current input electricity
Source (10), power conversion unit (20) and load (30), described power conversion unit (20) includes n sub three Port Translation devices,
Described load (30) includes n son load, and n is the natural number more than 1, and the output of direct-current input power supplying is as system input electricity
Pressure bus, the input of every height three Port Translation device is connected to input terminal voltage bus, every height three Port Translation device
Energy storage end is connected to energy storage terminal voltage bus, and the outfan of every height three Port Translation device all concatenates a son load；Described
Direct-current input power supplying (10) is direct voltage source or renewable energy source current, can be that single power supply can also be by multiple power supply strings
Composition in parallel；Described three Port Translation devices are isolated form three Port Translation device or non-isolation type three Port Translation device；Described three ends
Mouth changer includes a DC voltage input end, an outfan and an energy storage end, and wherein energy storage end is bidirectional power end
Mouthful, outfan is unidirectional power port or bidirectional power port；
The control method of the described direct current distributed terminator system based on three Port Translation devices is as follows: all sub three Port Translation devices
Control method identical, its control process is divided into the following two kinds situation:
A., when energy storage device is in charged state, each sub three Port Translation devices adopt the control strategy of energy storage end all stream, specifically
Control process is as follows:
Using the meansigma methodss of each sub three Port Translation device energy storage end electric currents or maximum as energy storage end current equalizing bus bar voltage signal
ib_bus, this signal as the Setting signal of each sub three Port Translation device energy storage end electric currents, with each sub three Port Translation device energy storage ends
Current feedback signal ibObtain both error signals v after the equal throttle regulator in energy storage end is adjustedbcs, this error signal and base
Quasi- voltage vinrefAs the Setting signal of this sub three Port Translation device input terminal voltage after superposition, defeated with this sub three Port Translation device
Enter terminal voltage feedback signal vinObtain both error signals v after input terminal voltage actuator is adjustedc, this error signal work
For the control signal of input terminal voltage, it is handed over carrier signal and intercepts drive signal, thus realizing this sub three Port Translation device
Control；
B., when energy storage device is in discharge condition, each sub three Port Translation devices are defeated using distributing according to respective output size
Enter to hold the control strategy of power, concrete control process is as follows:
Energy storage end electric current i by each sub three Port Translation devicesbDivided by respective output poCarry out standardization, obtain each sub three
The energy storage end electric current perunit value i of Port Translation device* b, with the meansigma methodss of each sub three Port Translation device energy storage end electric current perunit values or
It is worth as energy storage end perunit current equalizing bus bar voltage signal i greatly* b_bus, this signal is as each sub three Port Translation device energy storage end perunits
The Setting signal of electric current, with each sub three Port Translation device energy storage end perunit current signal i* bThrough energy storage end, perunit electric current all flows tune
Section device obtains both error signals v after adjustingbcs, this error signal and reference voltage vinrefAs this sub three port after superposition
The Setting signal of changer input terminal voltage, with this sub three Port Translation device input terminal voltage feedback signal vinThrough input electricity
Pressure actuator obtains both error signals v after adjustingc, this error signal as the control signal of input terminal voltage, its with carry
Ripple signal is handed over and is intercepted drive signal, thus realizing the control of this sub three Port Translation device.
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| CN106711994B (en) * | 2017-01-09 | 2018-10-12 | 清华大学 | The control method and control system of distributed generation resource electricity generation system |
| CN107749715B (en) * | 2017-11-17 | 2020-11-20 | 东南大学 | Direct-current power spring topology and control method thereof |
| CN108155790A (en) * | 2017-12-29 | 2018-06-12 | 北京天诚同创电气有限公司 | Two-way DC/DC converters and two-way voltage conversion system |
| CN108667337B (en) * | 2018-05-31 | 2024-01-30 | 西南交通大学 | High-power pulse load power supply device with rapid dynamic response and control method thereof |
| CN109980961B (en) * | 2019-03-26 | 2021-01-15 | 深圳市皓文电子有限公司 | Current equalizing method of multi-path parallel Boost type inversion module and inversion module |
| CN110212842B (en) * | 2019-06-06 | 2020-04-28 | 南通大学 | Three-port integrated converter for photovoltaic energy storage system and control method |
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| CN102624234A (en) * | 2012-04-20 | 2012-08-01 | 南京航空航天大学 | Full-bridge three-port direct current converter and control method thereof |
| CN103281009A (en) * | 2013-04-28 | 2013-09-04 | 苏州市职业大学 | Novel control circuit for solar photovoltaic power generation and control method thereof |
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| US8232669B2 (en) * | 2006-09-29 | 2012-07-31 | Ford Global Technologies, Llc | Energy conversion system for a vehicle |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102624234A (en) * | 2012-04-20 | 2012-08-01 | 南京航空航天大学 | Full-bridge three-port direct current converter and control method thereof |
| CN103281009A (en) * | 2013-04-28 | 2013-09-04 | 苏州市职业大学 | Novel control circuit for solar photovoltaic power generation and control method thereof |
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