CN107994642A - A kind of seamless power supply and load transfer system and method - Google Patents
A kind of seamless power supply and load transfer system and method Download PDFInfo
- Publication number
- CN107994642A CN107994642A CN201711370752.7A CN201711370752A CN107994642A CN 107994642 A CN107994642 A CN 107994642A CN 201711370752 A CN201711370752 A CN 201711370752A CN 107994642 A CN107994642 A CN 107994642A
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- power
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- 238000012546 transfer Methods 0.000 title claims abstract description 17
- 238000000034 method Methods 0.000 title claims abstract description 15
- 238000012544 monitoring process Methods 0.000 claims abstract description 31
- 238000010521 absorption reaction Methods 0.000 claims abstract description 14
- 238000005259 measurement Methods 0.000 claims abstract description 13
- 238000006243 chemical reaction Methods 0.000 claims description 18
- 230000002457 bidirectional effect Effects 0.000 claims description 6
- 230000002441 reversible effect Effects 0.000 claims description 6
- 230000001360 synchronised effect Effects 0.000 claims description 5
- 230000005611 electricity Effects 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 4
- 230000006641 stabilisation Effects 0.000 claims description 3
- 238000011105 stabilization Methods 0.000 claims description 3
- 230000004913 activation Effects 0.000 claims description 2
- 230000005669 field effect Effects 0.000 claims description 2
- 238000012360 testing method Methods 0.000 abstract description 8
- 230000008859 change Effects 0.000 description 6
- 238000001514 detection method Methods 0.000 description 6
- 238000004088 simulation Methods 0.000 description 4
- 230000000903 blocking effect Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000005404 monopole Effects 0.000 description 3
- 230000007547 defect Effects 0.000 description 2
- 230000009977 dual effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000007792 addition Methods 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 230000002045 lasting effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 230000001052 transient effect Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
- H02J7/0068—Battery or charger load switching, e.g. concurrent charging and load supply
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
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- H02J7/045—
Abstract
The invention discloses a kind of seamless power supply and load transfer system and method, belong to power supply and load transfer field, present system includes AC DC modular converters, descends programming module, two-way DC DC modular converters, voltage and current monitoring module, measurement module, sensing monitoring module and digital control module automatically.The present invention solves the problems, such as that DC power supply and electronic load configuration power output and power absorption is used alone；Avoid and DC power supply and load is applied in combination there are the shortcomings of dead zone voltage and system complex and nonrepeatability；More solve power supply and load switching problem, output power and absorbed power function perfectly switch so that the present invention can be good in the test applied to various active measured pieces, have certain application value and the prospect of marketing.
Description
Technical field
The invention belongs to power supply and load transfer field, and in particular to a kind of seamless power supply and load transfer system and side
Method.
Background technology
In the research and development and production test procedure of the system of progress and instrument, not only need to provide power input for measured piece,
Also to absorb the energy that measured piece discharges, to reach this purpose, a kind of common method be use single power supply for
Measured piece is powered, then the energy discharged with load absorption measured piece.The defects of this method is can not to realize power supply and bear
Carry the continuous conversion of function.In order to absorb the energy of measured piece, it is necessary to use the member such as powerful switch, relay in systems
Device, allows system to become extremely complex, and the reliability of system and repeatability all do not reach requirement.
For single DC power supply, can continuously output power, and electronic load can continuously absorb work(
Rate, and have outstanding DC precision, stability and quick dynamic response.Because measured piece has active and dynamic spy
Point, according to its state and operating condition, DC power supply and load combinations are got up, and are turned between output power and absorbed power
Change.
As shown in Figure 1, a kind of typical battery simulation device system (BSS), is exactly by DC power supply and electronic load combination
Get up, be powered and absorb.
VElectronic load>(VDC power supply-VDiode)。
DC power supply is in output state, measured piece absorbed power：VMeasured piece=(VDC power supply-VDiode)。
Measured piece is in output state, and electronic load absorbs electric current：VMeasured piece=VLoad。
Battery simulation device system is typical electrical voltage system；DC power supply and electronic load are all operated in constant pressure (CV) pattern
Under.The voltage of electronic load, which is set, is larger than DC power supply, between them there are a voltage difference, can cause a dead band
Voltage, makes battery simulation system can not work in this region.When measured piece absorbs electric current, voltage is by supply voltage
Maintain.When measured piece output current, its voltage rises, and the output of DC power supply will end, meanwhile, electronic load can enter
The work pattern of CV, and by voltage clamp on slightly higher level.Under normal conditions, it is necessary to add one in DC power output end
Blocking diode, with prevent measured piece start output power when, reverse current pours in down a chimney into power supply.But this testing scheme
There is following some unavoidable defects：
1st, DC power supply can not use distal end to sense, because if the distal end line of induction will in diode end, blocking diode
DC power supply can be caused unstable；
2nd, there are high impedance for the voltage dead band between power output and absorption.Need to DC power supply and electronic load difference
Voltage-programming instruction is sent, them is mutually tracked when BSS voltages change；
3rd, in order to coordinate the working status of DC power supply and electronic load in testing, it usually needs increasingly complex configuration；
4th, electronic load is had to the saltus step between cut-off and CV operating modes, can when electric current and temperature change,
The pressure drop of blocking diode can change, and cause between DC power supply and electronic load voltage, it is necessary to increase by hundreds of millivolts
Dead zone voltage.
3 and 4 two factors, limit flexibility and the precision of dual quadrant work, and have impact on the quiescent operation of system
Performance., can upper and lower tune as requested in order to compensate for the dead zone voltage under quiescent operation, it is necessary to control BSS voltage-programmings
It is whole, make magnitude of voltage closer to required voltage.However, since dead zone voltage is there are intrinsic dynamic transients, and then can be with electricity
Sub- load C V model transition weave in.
It is foregoing caused by non-overlapped operation interval to avoid using the completely overlapped method of operation interval
The problems such as dead zone voltage.
Fig. 2 is to be configured to operation interval completely overlapped DC power supply and electronic load.
ILoad>(IAbsorption maximum), fixed level.
VMeasured piece=VDC power supply。
Measured piece absorbed power：IDC power supply=(ILoad+ISupply)。
Measured piece supplies power：IDC power supply=(IAbsorption/negative value+ISupply)。
Electronic load works under CC patterns rather than CV patterns.The electric current of electronic load is arranged to fixed value, more than tested
The current maxima that part can provide.Electronic load will be remained under CC patterns, absorb fixed horizontal electric current and power,
The cross-cutting issue of pattern need not be tackled.DC power supply remains in cv mode, and supplies electric current all the time.Therefore no longer need
Want diode.This BSS configurations be in CV patterns all the time in whole supply and absorption region, without electronic load pattern intersect with
Dead zone voltage transient, would not also influence the BSS configurations comprising non-overlapped work.But this method is lacked there is also following
Point：
1st, DC power supply needs very big, so as to the required maximum current of measured piece and power are supplied at the same time, with
And the full current of electronic load continuous absorption.
2nd, electronic load often consumes whole power, and this point is must take into account for big system.
3rd, measurement needs to read the electric current of DC power supply and electronic load and seeks difference, is often subtracted each other with two big value
To a small value.Measurement accuracy can be affected at this time.
The content of the invention
For above-mentioned technical problem existing in the prior art, the present invention proposes a kind of seamless power supply and load transfer
System and method, design is reasonable, overcomes the deficiencies in the prior art, has good effect.
To achieve these goals, the present invention adopts the following technical scheme that：
A kind of seamless power supply and load transfer system, including AC-DC conversion module, programming module, two-way DC- are descended automatically
DC modular converters, voltage and current monitoring module, measurement module, sensing monitoring module and digital control module；
AC-DC conversion module, is configurable for providing the input direct voltage of 48V for system, exchanges the voltage of input
Scope is 100VAC-240VAC；
Automatically lower programming module, is configurable for, by carrying load absorption electric current, controlling the anti-of bi-directional DC-DC module
To circulation voltage, the stabilization of holding AC-DC output voltages；
Bi-directional DC-DC modular converter, is configurable for 48V direct current signals being converted into the voltage and electricity of user demand
Stream, while solve the bidirectional flow general character of power；
Voltage and current monitoring module, is configurable for providing feedback control loop for output voltage and electric current, there is provided voltage
With the feedback signal of electric current to digital control module；
Measurement module, the system of being configurable for provide a user the real-time measurement of the signals such as display voltage, electric current, power
Value.
Sense monitoring module, be configured as the extension to system voltage and current monitoring module, it is ensured that measured piece is located always
In guard mode.
Digital control module, is configurable for realizing the closed loop of the signal including output voltage, electric current and power
Control, completes corresponding closed loop control algorithm.
Preferably, carry load absorption rated power the 10% of automatic lower programming module, when needing larger electric current,
External power dissipation module.
Preferably, bi-directional DC-DC modular converter, including two-way full-bridge, synchronous rectifier and multiple filter, are imitated using field
Should pipe substitute diode and realize two-way full-bridge and synchronous rectification, make the power there is the bidirectional flow general character；Using Multi-stage precise member device
Part realizes multiple-stage filtering, the power output is had low-down noise.
In addition, the present invention is it is also mentioned that a kind of seamless power supply and load transfer method, this method use as described above one
The power supply and load transfer system that kind is seamless, specifically comprise the following steps：
Step 1：To system electrification, the direct current of 48V is provided by AC-DC conversion module for system, meets system standby
Operation；
Step 2：The operating mode of initialization system is CC operating modes (if system operating mode is arranged to CV Working moulds
Formula, then system will only be operated in first quartile)；
Step 3：Activation system, voltage and current monitoring module and sensing monitoring module operation, system is according to voltage and electricity
Flow monitoring module and sensing monitoring module judge the working status of measured piece；
If：Judging result is measured piece absorbed power, then measured piece is load, and system provides power input for it, automatically
Lower programming module does not work, AC-DC conversion module, bi-directional DC-DC modular converter, voltage and current monitoring module, measurement module,
Sense monitoring module and digital control module forms closed control circuit, carry out closed-loop control, system is operated in first quartile；
Or judging result is measured piece output power, then measured piece is source, and system is switched to load, absorbs measured piece release
Energy out, lower programming module and AC-DC conversion module, bi-directional DC-DC modular converter, voltage and current monitor mould automatically
Block, measurement module, sensing monitoring module and digital control module form closed control circuit, carry out closed-loop control, system work
In the second quadrant；
Step 4：Realize the bumpless transfer of source and loading functional.
Advantageous effects caused by the present invention：
The present invention solves the problems, such as that DC power supply and electronic load configuration power output and power absorption is used alone；Keep away
Exempt from DC power supply and load is applied in combination that there are the shortcomings of dead zone voltage and system complex and nonrepeatability；More solve
Power supply and load switching problem, output power and absorbed power function perfectly switch so that the present invention can be good at applying
In the test of various active measured pieces, there is certain application value and the prospect of marketing.
Brief description of the drawings
Fig. 1 is common DC power supply and electronic load testing scheme schematic diagram.
Fig. 2 is that the DC power supply and electronic load testing scheme for battery simulation device system for carrying out overlapping work are illustrated
Figure.
Fig. 3 is the I/V images of four-quadrant.
Fig. 4 is the functional block diagram of the method for the present invention.
Embodiment
Below in conjunction with the accompanying drawings and embodiment is described in further detail the present invention：
As shown in figure 3, in this four-quadrant, I in figure of monopole, the electric current of bi-directional power, voltage power supply region and
II quadrants.Monopole, bi-directional power can export and absorb electric current, but voltage must be positive voltage.Monopole, bi-directional power both can be with
As DC power supply, and electronic load can be used as, be a kind of dual quadrant DC power supply.Fig. 4 is the principle of the present invention block diagram.
Present system is operated in I and II quadrants, according to the active nature of measured piece, automatically switches in I and II quadrants.Quilt
When surveying part to carry, system provides power input for it, and system is operated in first quartile；When measured piece is source, system is switched to negative
Carry, absorb the energy that measured piece discharges, system is operated in the second quadrant.
The principle of the present invention as shown in figure 4, by AC-DC conversion module, descend programming module, bi-directional DC-DC modulus of conversion automatically
Block, voltage and current monitoring module, measurement module, sensing monitoring module and digital control module composition.
AC-DC conversion module, mainly provides the input direct voltage of 48V for system, and the voltage range for exchanging input is
100VAC to 240VAC, frequency can be 50Hz to 60Hz and 400Hz.
48V direct current signals, are mainly converted into the voltage and current of user demand, at the same time by bi-directional DC-DC modular converter
The bidirectional flow general character of power is solved, mainly including function modules such as two-way full-bridge, synchronous rectification, multiple-stage filterings.Two-way full-bridge is same
Step commutation technique is to substitute diode using field-effect tube so that power has the bidirectional flow general character, in the case of dynamic load, carries
For more preferable power output stability.Multiple-stage filtering is realized using Multi-stage precise component so that power output has very
Low noise, and the capacitance quantity of power output end is reduced, relatively low power supply output capacitance, it is allowed to which power supply output is quick to be become
Change, using this technology, a fast testing system can be set up.
Automatically lower programming module, mainly realizes absorbed inside and the exterior control absorbed.Due to the pre- Voltage stabilizing module of the first order
Realize that AC-DC conversions are one-way flows, when measured piece is energy stores component, if tested voltage is higher than programming value
When, electric current will cause the voltage of AC-DC conversion module to rise, descend programming Control automatically in bi-directional DC-DC intermodule reverse circulated
Module will be by carrying load absorption electric current, while controls the voltage of the reverse circulated of bi-directional DC-DC module, keeps AC-DC defeated
Go out the stabilization of voltage, and make to descend programming Control module only energy of the dissipation measured piece through bi-directional DC-DC module reverse circulated automatically.
The 10% of rated power can only be absorbed by carrying loading functional, when needing larger electric current, need external power dissipation module, automatically
Lower programming module can protect measured piece well by allowing this function of power supply absorption electric current.If voltage on measured piece
That drops is lower, it will prevent or slow down the reduction of voltage.
Voltage and current monitoring module, there is provided the feedback signal of voltage and current to digital control module.This module is
Output voltage and electric current provide feedback control loop, further include bi-directional DC-DC modulus of conversion detection voltage in filter circuit part in the block
With the embedded loop of electric current, in whole voltage and current opereating specification, these embedded loops carry these embedded loops for power supply
Consistent output characteristics has been supplied, has been not in any fortuitous event in test therefore.For output electric current measure, selection makes
Analogue loop is substituted with digital current control loop, therefore using nonlinear adjustment technology.Change suddenly in load
When, this technology causes power supply to be enable to respond quickly, and makes measured piece preferably be protected and export more to stablize.
Sense monitoring module, it is allowed to which user is to system out connector to appointing between measured piece DUT and between this 2 points
It is where square, adjusting is extended to system output, this is the expansion technique to voltage and current detection module.Sense monitoring module
Using lasting detection technique so that after output signal is opened, detection line can also be continued to monitor.This technology is simultaneously
From the influence of power supply output, detection line is monitored always, it is ensured that measured piece is constantly in guard mode.This module is also
Reverse, the short-circuit conditions of detection line can be monitored, measured piece is obtained the protection of maximum.
Certainly, described above is not limitation of the present invention, and the present invention is also not limited to the example above, this technology neck
The variations, modifications, additions or substitutions that the technical staff in domain is made in the essential scope of the present invention, should also belong to the present invention's
Protection domain.
Claims (4)
1. a kind of seamless power supply and load transfer system, it is characterised in that：Including AC-DC conversion module, automatic lower programming mould
Block, bi-directional DC-DC modular converter, voltage and current monitoring module, measurement module, sensing monitoring module and digital control module；
AC-DC conversion module, is configurable for providing the input direct voltage of 48V for system, exchanges the voltage range of input
For 100VAC-240VAC；
Automatically lower programming module, is configurable for, by carrying load absorption electric current, controlling the reverse flow of bi-directional DC-DC module
Be powered pressure, keeps the stabilization of AC-DC output voltages；
Bi-directional DC-DC modular converter, is configurable for 48V direct current signals being converted into the voltage and current of user demand, together
When solve power the bidirectional flow general character；
Voltage and current monitoring module, is configurable for providing feedback control loop for output voltage and electric current, there is provided voltage and electricity
The feedback signal of stream is to digital control module；
Measurement module, the system of being configurable for provide a user the real-time measurement values of the signals such as display voltage, electric current, power.
Sense monitoring module, be configured as the extension to system voltage and current monitoring module, it is ensured that measured piece is constantly in guarantor
Shield state.
Digital control module, is configurable for realizing the closed-loop control of the signal including output voltage, electric current and power,
Complete corresponding closed loop control algorithm.
2. seamless power supply according to claim 1 and load transfer system, it is characterised in that：Automatic lower programming module
The 10% of load absorption rated power is carried, when needing larger electric current, external power dissipation module.
3. seamless power supply according to claim 1 and load transfer system, it is characterised in that：Bi-directional DC-DC modulus of conversion
Block, including two-way full-bridge, synchronous rectifier and multiple filter, using field-effect tube substitute diode come realize two-way full-bridge and
Synchronous rectification, makes power have the bidirectional flow general character；Multiple-stage filtering is realized using Multi-stage precise component, there is power output
Low-down noise.
4. a kind of seamless power supply and load transfer method, it is characterised in that：Using as claimed in claim 1 a kind of seamless
Power supply and load transfer system, specifically comprise the following steps：
Step 1：To system electrification, the direct current of 48V is provided by AC-DC conversion module for system, meets that system standby is run；
Step 2：The operating mode of initialization system is CC operating modes；
Step 3：Activation system, voltage and current monitoring module and sensing monitoring module operation, system are supervised according to voltage and current
Control module and sensing monitoring module judge the working status of measured piece；
If：Judging result is measured piece absorbed power, then measured piece is load, and system provides power input for it, automatic lower volume
Journey module does not work, AC-DC conversion module, bi-directional DC-DC modular converter, voltage and current monitoring module, measurement module, sensing
Monitoring module and digital control module form closed control circuit, carry out closed-loop control, and system is operated in first quartile；
Or judging result is measured piece output power, then measured piece is source, and system is switched to load, absorbs measured piece and discharges
Energy, automatically lower programming module and AC-DC conversion module, bi-directional DC-DC modular converter, voltage and current monitoring module, survey
Measure module, sensing monitoring module and digital control module and form closed control circuit, carry out closed-loop control, system is operated in second
Quadrant；
Step 4：Realize the bumpless transfer of source and loading functional.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711370752.7A CN107994642A (en) | 2017-12-19 | 2017-12-19 | A kind of seamless power supply and load transfer system and method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711370752.7A CN107994642A (en) | 2017-12-19 | 2017-12-19 | A kind of seamless power supply and load transfer system and method |
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| Publication Number | Publication Date |
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| CN107994642A true CN107994642A (en) | 2018-05-04 |
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ID=62039137
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| CN201711370752.7A Pending CN107994642A (en) | 2017-12-19 | 2017-12-19 | A kind of seamless power supply and load transfer system and method |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6542385B1 (en) * | 2000-11-22 | 2003-04-01 | Teradyne, Inc. | DUT power supply having improved switching DC-DC converter |
| CN101813755A (en) * | 2010-04-09 | 2010-08-25 | 福州福光电子有限公司 | Charge and discharge test equipment for full on-line storage battery pack |
| CN104410363A (en) * | 2014-12-03 | 2015-03-11 | 黄河科技学院 | Solar battery simulator |
| CN204216790U (en) * | 2014-11-10 | 2015-03-18 | 台州学院 | A kind of scanning power supply able to programme |
-
2017
- 2017-12-19 CN CN201711370752.7A patent/CN107994642A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6542385B1 (en) * | 2000-11-22 | 2003-04-01 | Teradyne, Inc. | DUT power supply having improved switching DC-DC converter |
| CN101813755A (en) * | 2010-04-09 | 2010-08-25 | 福州福光电子有限公司 | Charge and discharge test equipment for full on-line storage battery pack |
| CN204216790U (en) * | 2014-11-10 | 2015-03-18 | 台州学院 | A kind of scanning power supply able to programme |
| CN104410363A (en) * | 2014-12-03 | 2015-03-11 | 黄河科技学院 | Solar battery simulator |
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Application publication date: 20180504 |
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