CN100538385C - Electronic load device and emulation mode thereof - Google Patents
Electronic load device and emulation mode thereof Download PDFInfo
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- CN100538385C CN100538385C CN 200610156635 CN200610156635A CN100538385C CN 100538385 C CN100538385 C CN 100538385C CN 200610156635 CN200610156635 CN 200610156635 CN 200610156635 A CN200610156635 A CN 200610156635A CN 100538385 C CN100538385 C CN 100538385C
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Abstract
The invention provides a kind of electronic load device and emulation mode thereof, be applicable to emulation one circuit unit, a supply unit is carried out electric power draw a year test.This electronic load device comprises a power consumption unit, an electric power detecting unit and a digital signal processor; The power consumption unit is connected in this supply unit, and it has the mechanism of an adjustable variable current, carries in order to this supply unit is drawn; The electric power detecting unit is coupled between power consumption unit and the supply unit, can measure the power consumption unit supply unit is drawn magnitude of voltage and the current value that carries, and export one first voltage value signal and one first current value signal in the very first time; Digital signal processor can receive this first voltage value signal and this first current value signal, and according to the equiva lent impedance parameter of its inner stored this circuit unit, calculate out magnitude of voltage and the current value of second time, and then export an impedance modulating signal to the power consumption unit, with the current value of the mechanism of adjusting this adjustable variable current.
Description
Technical field
The present invention is applicable to that especially in regard to a kind of power supply unit is carried out electric power draws year electronic load device of test and relevant emulation mode thereof about a kind of electronic load device.
Background technology
Supply unit is widely used in daily life, its range of application contains general information, communication, consumer electronics, transportation equipment, commercial unit and military field, its function is for driving each circuit unit and keeping voltage quasi position, for keeping the key factor of system's normal operation.Therefore, the main considerations of supply unit design, except reducing cost, first heavy high-reliability.
Electronic load device is in supply unit exploitation and the manufacture process, basic and important instrument and equipment.The combination of its alternative actual resistance, electric capacity, the load condition of assistance emulation supply unit output terminal is to provide relevant research and development, QC and production line Test Application.Present electronic load device provides the pattern of four kinds of artificial circuit unit, comprising constant current mode, constant voltage mode, decide power mode and decide resistance mode.Yet, constant current mode, constant voltage mode and supply unit electric power is drawn the situation of carrying when decide power mode and being difficult to simulate the general circuit unit activating, therefore, at present more than to decide the state of activation of resistance mode artificial circuit unit.
Deciding under the resistance mode, electronic load device draws the current value that carries, along with magnitude of voltage is made linear change, yet, in general circuit unit, practical impedance has also comprised the composition of electric capacity and inductance except resistance, described composition all can cause pulling load current to change, and this is for deciding the disappearance that resistance mode can't satisfy.
See also Fig. 1, Fig. 1 is the voltage and current waveform of a circuit unit.Second channel among the figure (ch2) is the current waveform of circuit unit for this reason, at T start-up time
ONTo time T
1Between, circuit unit is in state of activation, and between A point on the figure and B point, electric current presents curve state and rises, and therefore, can obviously find out the action of charging of electric capacity in this circuit unit.As seen during the deciding resistance mode and can't simulate this state of activation of electronic load, circuit unit carries a situation to drawing of supply unit electric power, therefore, can't guarantee the fiduciary level of supply unit.On the other hand, if therefore improve the output power of supply unit, also will cause the anxiety of energy dissipation and raising cost of products.
This case inventor is because the disappearance of above-mentioned existing electronic load device, and think of and electronic load device are digitized as the trend that promotes its fiduciary level, and the operation efficiency of signal processor (Digital SignalProcessor) is also with the development of semiconductor fabrication now, constantly upwards promote, the present invention is proposed, phase is improved the disappearance of existing technology by the proposition of this case, with beneficial to the relevant design manufacturer.
Summary of the invention
A purpose of the present invention is to provide a kind of electronic load device, and it goes out the impedance operator of a circuit unit by dynamic simulation, a supply unit is carried out electric power draw and carry test, can promote the design correctness of supply unit.
Another object of the present invention is to provide a kind of emulation mode of electronic load device,, can correctly simulate a circuit unit drawing of one supply unit carried situation by the quick calculation function of digital signal processor.
Another purpose of the present invention is to provide a kind of electronic load device, and it can promote the design correctness of supply unit, and and then reduces the cost of supply unit and energy-conservation.
The invention provides a kind of electronic load device, be applicable to emulation one circuit unit, a supply unit is carried out electric power draw a year test.This electronic load device comprises a power consumption unit, an electric power detecting unit and a digital signal processor.The power consumption unit is connected in this supply unit, and it has the mechanism of an adjustable variable current, carries in order to this supply unit is drawn.The electric power detecting unit is coupled between power consumption unit and the supply unit, can measure the power consumption unit supply unit is drawn magnitude of voltage and the current value that carries, and export one first voltage value signal and one first current value signal in a very first time.The interior reservoir of digital signal processor has the equiva lent impedance parameter of this circuit unit, it can receive this first voltage value signal and this first current value signal, and according to this circuit unit equiva lent impedance parameter, calculate out magnitude of voltage and the current value of one second time, and then export an impedance modulating signal to the power consumption unit, with the current value of the mechanism of adjusting this adjustable variable current, wherein this second time is continuously in this very first time.
Described this digital signal processor in the magnitude of voltage of this very first time and the load module function of current value, calculates out magnitude of voltage and the current value of this second time according to a strain.
Described equiva lent impedance parameter has comprised the equivalent resistance of this circuit unit, and can further comprise the equivalent capacitance value of this circuit unit and this circuit unit equivalent resistance both, or both one of them.And, but this equivalence impedance parameter strain at least one particular variables, this particular variables can be the magnitude of voltage of a time value, this electronic load device or the current value of this electronic load device.
The present invention also discloses a kind of emulation mode of electronic load device, be applicable to an electronic load device emulation one circuit unit, one supply unit is drawn a year test, and the step of this emulation mode comprises: at first, measure this electronic load device in magnitude of voltage and the current value of a very first time.Secondly, a digital signal processor calculates out magnitude of voltage and the current value of one second time according to magnitude of voltage and the current value of this very first time, and wherein this second time is continuously in this very first time.Subsequently, adjust the resistance value of this electronic load device, make this electronic load device draw the current value that carries this second time.
In described this emulation mode,, also comprise the step of the equiva lent impedance parameter of importing this circuit unit measuring this electronic load device before the step of the magnitude of voltage of this very first time and current value.
In described this emulation mode, at magnitude of voltage and the current value of this digital signal processor according to this very first time, calculate out in the step of the magnitude of voltage of this second time and current value, this digital signal processor is simultaneously according to this equivalence impedance parameter, with magnitude of voltage and the current value that calculates out this second time.
Described this digital signal processor in the magnitude of voltage of this very first time and the load module function of current value, calculates out magnitude of voltage and the current value of this second time according to a strain.
Describedly should comprise the equivalent resistance of this circuit unit by the equivalence impedance parameter, and can further comprise the equivalent capacitance value of this circuit unit and this circuit unit equivalent resistance both, or both one of them.And, but this equivalence impedance parameter strain at least one particular variables, this particular variables can be the magnitude of voltage of a time value, this electronic load device or the current value of this electronic load device.
As seen, by disclosed electronic load device and emulation mode thereof, utilize digital signal processor, according to the equiva lent impedance parameter of the circuit unit of this electronic load device institute emulation, with magnitude of voltage and the current value of the very first time, calculate out magnitude of voltage and the current value of second time.Thus, electronic load device can simulate this circuit unit more accurately and the electric power of supply unit be drawn the impedance operator of carrying, can apply to the design process of supply unit, make the electricity needs of deviser at load, design and meet the specification and product cheaply, and can promote the fiduciary level that the product QC detects.Compared to prior art, because of correct dummy load is drawn the situation of carrying to supply unit, and use the higher supply unit of power, by the present invention, can reach energy savings, with the effect that reduces cost.
Description of drawings
Fig. 1 is the voltage and current waveform of a circuit unit;
Fig. 2 is the equivalent circuit diagram that a circuit unit is connected in a supply unit;
Fig. 3 is the system architecture synoptic diagram of electronic load device of the present invention;
Fig. 4 is the system architecture synoptic diagram of an embodiment of electronic load device of the present invention;
Fig. 5 is the flow chart of steps of the emulation mode of electronic load device of the present invention;
Fig. 6 is the voltage and current waveform of this circuit unit that utilizes the emulation mode analogous diagram 1 of electronic load device of the present invention.
The main element symbol description:
1: electronic load device 3: the electric power detecting unit
2: power consumption unit 4: digital signal processor
5: set interface 8: circuit unit
9: supply unit 31: voltmeter
20: variable-impedance load 32: galvanometer
21: D/A conversion unit 33: analog digital converting unit
S100～S120: each steps flow chart
A, B: indicate some C
L: load capacitance
I
S: input current R
L1, R
L2: pull-up resistor
V
0: output voltage T
ON, T
1: the time
L
S: series inductance R
S: resistance in series
V
S: input voltage
Embodiment
The present invention is described in detail below in conjunction with accompanying drawing.
At first, please consult Fig. 2 earlier, this figure is the equivalent circuit diagram that a circuit unit 8 is connected in a supply unit 9, and this figure has shown the load module of a typical switched power supplier.Among Fig. 2, the equivalent electrical circuit of circuit unit 8 is by a load capacitance C
LWith two pull-up resistor R
L1, R
L2Institute in parallel constitutes, generally is designed to be connected in the circuit unit 8 of supply unit 9, mostly can with one or the individual electric capacity of majority reach the purpose of voltage stabilizing, this load capacitance C
LPromptly be meant its equivalent capacity; Pull-up resistor R
L1, R
L2Be respectively the power termination that resistor and transistor constituted of circuit unit 8.Simultaneously, series inductance L
SWith resistance in series R
SThe line of electric force that is connected in supply unit 9 in circuit unit 8 forms.
Load capacitance C in this elder generation with Fig. 2
L, pull-up resistor R
L1, R
L2, series inductance L
SWith resistance in series R
SBe defined as the equiva lent impedance parameter of circuit unit 8, in order to statement the present invention.
Be via the input current I in the load module of Kirchhoff electric current and voltage law (KCL, KVL) analysis chart 2
SAnd input voltage V
S, can obtain following (1), (2) formula respectively:
I
S(n)＝C
L[V
0(n)-V
0(n-1)]/Δt+V
0(n)/R
L...(1)
V
S(n)-V
0(n)＝L
S[I
S(n)-I
S(n-1)]/Δt+R
SI
S(n)...(2)
Wherein, Δ t is a sampling frequency, R
LBe pull-up resistor R
L1, R
L2Equivalent resistance, V
S(n-1), I
S(n-1), V
0(n-1) be input voltage, electric current and the output voltage of the very first time, V
S(n), I
S(n), V
0(n) be input voltage, electric current and the output voltage of second time.Separate above (1), (2) formula, can get following load module function (3), (4):
I
S(n)＝[Y
L_CR×(V
S(n)+Z
LS×I
S(n-1))-Y
CLV
0(n-1)]/[Y
L_CR×(Z
LS+R
S)+1]
...(3)
V
0(n)＝V
S(n)-Z
LS×(I
S(n)-I
S(n-1))-R
SI
S(n)...(4)
Wherein, Y
L_CRBe C
LWith R
LElectricity in parallel is led Z
LSBe L
SResistance value, Y
CLBe C
LElectricity lead.
Y
L_CR＝C
L/Δt+1/R
L
Z
LS＝L
S/Δt
Y
CL＝CL/Δt
By above result as can be known, by the equiva lent impedance parameter of circuit unit 8, and input voltage Vs (n-1), the input current I of the very first time
S(n-1), output voltage V
0(n-1) with the input voltage Vs (n) of second time, can deduce out in second time, 8 pairs of supply units 9 of circuit unit draw magnitude of voltage Is (n) and the current value Vo (n) that carries.
Wherein, the input voltage Vs (n) of second time utilizes a voltmeter directly to measure and learns, above-mentioned (3) formula of substitution and obtain Is (n) again, and then Vs (n) and above-mentioned (4) formula of Is (n) substitution obtained Vo (n).
In addition, the input voltage Vs (n) of second time also can calculate by the extrapolation mode, because the input voltage before second time is known, therefore can get its first two input voltage Vs (n-1) and Vs (n-2), above-mentioned two input voltage values are known, therefore as long as utilize extrapolation just can calculate Vs (n) again, substitution above-mentioned (3) and (4) formula respectively just can be obtained Is (n) and Vo (n) again.
Then, see also Fig. 3, Fig. 3 is the system architecture synoptic diagram of electronic load device of the present invention, and this case inventor results in based on above-mentioned, proposes the system architecture of the electronic load device 1 of this figure, carries situation with drawing of 8 pairs one supply units 9 in artificial circuit unit.As shown in the drawing, an electronic load device 1 is connected in a supply unit 9, and 8 pairs of supply units in artificial circuit unit 9 carry out electric power and draw a year test.This electronic load device 1 comprises a power consumption unit 2, an electric power detecting unit 3 and a digital signal processor 4.
Digital signal processor 4 is according to load module function (3), (4), input voltage, electric current and output voltage according to the very first time, and the equiva lent impedance parameter of circuit unit 8, deduce out in second time, 8 pairs of supply units 9 of circuit unit draw magnitude of voltage Vo (n) and the current value I s (n) that carries.
The equiva lent impedance parameter of circuit unit 8 has comprised the equivalent resistance of this circuit unit 8, and can further comprise the equivalent capacitance value of this circuit unit 8 and this circuit unit 8 equivalent resistance both, or both one of them.In addition, this equivalence impedance parameter can non-certain value, and it can be the function of strain at least one particular variables.In addition, this particular variables can be the magnitude of voltage or the current value of a time value, this electronic load device 1.
See also Fig. 4, Fig. 4 is the system architecture synoptic diagram of an embodiment of electronic load device of the present invention.Among this figure, electronic load device 1 comprises that also one sets interface 5, electric power detecting unit 3 has comprised a voltmeter 31, a galvanometer 32 and an analog digital converting unit 33, and power consumption unit 2 has comprised a D/A conversion unit 21 and a variable-impedance load 20.
The voltmeter 31 of electric power detecting unit 3 and galvanometer 32 are connected to the line of electric force between this electronic load device and this supply unit, with magnitude of voltage and the current value that measures this very first time, and the result imported analog digital converting unit 33, analog digital converting unit 33 again should the very first time magnitude of voltage and current value be converted to digitized first voltage value signal and this first current value signal, and export this binary signal to digital signal processor 4.
As previously mentioned, digital signal processor 4 is after receiving this first voltage value signal and this first current value signal, will be according to the equiva lent impedance parameter of this circuit unit 8, calculate out magnitude of voltage and the current value of one second time, and then export the D/A conversion unit 21 of an impedance modulating signal to power consumption unit 2, to control the resistance value of this variable-impedance load 20, make this variable-impedance load 20 that the electric power of supply unit 9 is drawn to carry and be the magnitude of voltage Vo (n) of this second time and current value I s (n).Variable-impedance load 20 does not herein just remake at this and gives unnecessary details for having now.
Then, see also Fig. 5, this figure is the flow chart of steps of the emulation mode of electronic load device of the present invention, is applicable to electronic load device 1 emulation one circuit unit 8, supply unit 9 is carried out electric power draw a year test, and relevant system architecture is please consulted Fig. 3 simultaneously.The step of this emulation mode comprises: at first, measure this electronic load device 1 in magnitude of voltage and the current value (seeing step S100) of a very first time.Secondly, digital signal processor 4 calculates out magnitude of voltage and the current value of one second time according to magnitude of voltage and the current value of this very first time, and wherein this second time is continuously in this very first time (seeing step S110).Subsequently, adjust the resistance value of power consumption unit 2 in this electronic load device 1, make this electronic load device 1 that the electric power of supply unit 9 is drawn to carry and be the current value of this second time (seeing step S120).
In the above-mentioned emulation mode, before step S100, also comprise the step of the equiva lent impedance parameter of importing this circuit unit 8.
In the above-mentioned emulation mode, in step S120, digital signal processor 4 is according to load module function (3), (4) of strain in magnitude of voltage and the current value of this very first time, and the equiva lent impedance parameter, calculates out magnitude of voltage and the current value of this second time.
The artificial affirmation of this case invention feasibility of the present invention is also carried out actual emulation according to the system architecture of Fig. 3.See also Fig. 6, this figure is the voltage and current waveform of this circuit unit that utilizes the emulation mode analogous diagram 1 of electronic load device of the present invention.The inventor estimates that to the equiva lent impedance parameter of the circuit unit of Fig. 1 with substitution load function, the method for the equiva lent impedance parameter of this estimation circuit unit and result are not emphasis of the present invention in advance, therefore, does not just remake at this and to give unnecessary details.As seen from Figure 6, (Fig. 1 indicates an A, B) electric capacity carried a situation to drawing of electric power when the present invention can simulate and activate, and this be existing constant current mode, decide resistance mode, constant voltage mode reaches the electronic load of deciding power mode and all can't reach.
As seen, by the electronic load device that the invention described above disclosed and the illustrated example and the checking of emulation mode thereof, the electric power that the described electronic load device 1 of this case can simulate 8 pairs of supply units 9 of circuit unit exactly draws the impedance operator of carrying, therefore real all beneficial to design, the QC of supply unit product, can reach the fiduciary level that improves the supply unit product and reduce many effects such as cost of products.
Though the present invention illustrates as above with preferred embodiments, yet it is not in order to limit spirit of the present invention and the invention entity only terminates in the foregoing description.But the modification of being done in not breaking away from spirit of the present invention and scope all should be included in the following claim.
Claims (10)
1. an electronic load device is applicable to emulation one circuit unit, a supply unit is carried out electric power draw a year test, it is characterized in that described electronic load device comprises:
One power consumption unit is connected in described supply unit, and it has the mechanism of an adjustable variable current, carries in order to described supply unit is drawn;
One electric power detecting unit, be coupled between described power consumption unit and the described supply unit, in a very first time, measure described power consumption unit described supply unit is drawn magnitude of voltage and the current value that carries, and export one first voltage value signal and one first current value signal; And
One digital signal processor, store the equiva lent impedance parameter of described circuit unit, described digital signal processor receives described first voltage value signal and the first current value signal, and according to described equiva lent impedance parameter, calculate out magnitude of voltage and the current value of one second time, and then export an impedance modulating signal to described power consumption unit, with the current value of the mechanism of adjusting described adjustable variable current.
2. electronic load device according to claim 1 is characterized in that, the strain of described equiva lent impedance parameter is at least one particular variables, and described particular variables is the magnitude of voltage of a time value, described electronic load device or the current value of described electronic load device.
3. electronic load device according to claim 1 is characterized in that, described digital signal processor in the magnitude of voltage of the described very first time and the load module function of current value, calculates out magnitude of voltage and the current value of described second time according to a strain.
4. electronic load device according to claim 1, it is characterized in that, described electric power detecting unit has comprised that a voltage takes into account a galvanometer, described voltmeter is connected between described electronic load device and the described supply unit, and described galvanometer is connected in series with in the loop of described electronic load device and described supply unit, with magnitude of voltage and the current value that measures the described very first time.
5. electronic load device according to claim 1, it is characterized in that, described power consumption unit has comprised a D/A conversion unit and a variable-impedance load, described D/A conversion unit receives described impedance modulating signal, to control the current value of described variable-impedance load, make described variable-impedance load draw the current value that carries described second time.
6. the emulation mode of an electronic load device is applicable to an electronic load device emulation one circuit unit, a supply unit is drawn carry test, it is characterized in that described emulation mode may further comprise the steps:
Measure described electronic load device in magnitude of voltage and the current value of a very first time;
One digital signal processor calculates out magnitude of voltage and the current value of one second time according to magnitude of voltage and the current value of the described very first time, and wherein said second time is continuously in the described very first time; And
Adjust the resistance value of described electronic load device, make described electronic load device draw the current value that carries described second time according to the impedance that sets.
7. emulation mode according to claim 6 is characterized in that, is measuring described electronic load device before the step of the magnitude of voltage of the described very first time and current value, and is further comprising the steps of:
Import the equiva lent impedance parameter of described circuit unit.
8. emulation mode according to claim 7, it is characterized in that, at magnitude of voltage and the current value of described digital signal processor according to the described very first time, calculate out in the step of the magnitude of voltage of described second time and current value, described digital signal processor is simultaneously according to described equiva lent impedance parameter, with magnitude of voltage and the current value that calculates out described second time.
9. emulation mode according to claim 7 is characterized in that, the strain of described equiva lent impedance parameter is at least one particular variables, and described particular variables is the magnitude of voltage of a time value, described electronic load device or the current value of described electronic load device.
10. emulation mode according to claim 7, it is characterized in that, at magnitude of voltage and the current value of described digital signal processor according to the described very first time, calculate out in the step of the magnitude of voltage of described second time and current value, described digital signal processor in the magnitude of voltage of the described very first time and the load module function of current value, calculates out magnitude of voltage and the current value of described second time according to a strain.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200610156635 CN100538385C (en) | 2006-12-29 | 2006-12-29 | Electronic load device and emulation mode thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200610156635 CN100538385C (en) | 2006-12-29 | 2006-12-29 | Electronic load device and emulation mode thereof |
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| CN100538385C true CN100538385C (en) | 2009-09-09 |
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Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102033146A (en) * | 2009-09-29 | 2011-04-27 | 致茂电子(苏州)有限公司 | Electronic load with light emitting diode simulation characteristic and light emitting diode characteristic simulation method |
| CN101949962A (en) * | 2010-05-27 | 2011-01-19 | 东莞市锐源仪器有限公司 | Programmable electronic load |
| US8664921B2 (en) * | 2011-08-04 | 2014-03-04 | Tektronix, Inc. | Means of providing variable reactive load capability on an electronic load |
| CN103698562B (en) * | 2013-12-26 | 2016-03-16 | 艾德克斯电子（南京）有限公司 | A kind of electronic load device and emulation mode thereof |
| CN104360291A (en) * | 2014-12-04 | 2015-02-18 | 艾德克斯电子（南京）有限公司 | Electronic load device for testing LED (Light Emitting Diode) driving power supply and test method thereof |
| CN107908135B (en) * | 2017-11-29 | 2020-09-08 | 常州同惠电子股份有限公司 | Digital implementation method for soft start of direct current electronic load |
| CN109030947B (en) * | 2018-07-18 | 2021-02-26 | 常州同惠电子股份有限公司 | Method for calculating equivalent impedance of electronic load simulation direct current motor |
| CN113094230B (en) * | 2021-03-31 | 2024-03-12 | 宁畅信息产业(北京)有限公司 | Power consumption monitoring method and power consumption monitoring main board |
| CN114281180A (en) * | 2021-12-21 | 2022-04-05 | 海光信息技术股份有限公司 | Integrated circuit load adjusting method and related device |
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| CN101210956A (en) | 2008-07-02 |
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