CN1259674A - A. C. electron load simulator - Google Patents
A. C. electron load simulator Download PDFInfo
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- CN1259674A CN1259674A CN 98124698 CN98124698A CN1259674A CN 1259674 A CN1259674 A CN 1259674A CN 98124698 CN98124698 CN 98124698 CN 98124698 A CN98124698 A CN 98124698A CN 1259674 A CN1259674 A CN 1259674A
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Abstract
The present invention relates to A. C. electronic load imitation device, in particular, A. C. electronic load imitation device of different A. C. load, such as resistance, inductance and capacitance. It is characterized in that it includes: a detecting circuit, two input ends are bridge-connected on A. C power source, current wave form producing circuit, voltage current phase control circuit, switch circuit, which includes four cut over switches, one rectification circuit, parallelly connected on two output ends of said switch circuit, a voltage current change-over circuit and is connected to the output end of rectification circuit. Use phase control to produce current control wave shape simitar to lag behind or lead with the power source voltage, thereby can imitate current wave shape of any compound load.
Description
The invention relates to a kind of alternating current electronic load analogue means, but be meant especially that a kind of analog electrical is resistive, inductive, and the alternating current electronic load analogue means of different AC load such as capacitive character.
In modern industry instrument, electrical equipment, often all need to use AC power equipment.Frequent employed AC power equipment in for example present industry member includes uninterrupted power supply (UPS), phase inverter (INVERTER), voltage stabilizer (VOLTAGE REGULATOR), amplifier (AMPLIFIER) etc.These various AC power equipment in order to understand its every electrical specification, often all need to connect actual electrical load after design, assembling are finished, and do test, record, the improvement of every electrical specification.Since must to prepare various alternating current electronic load analogue means, so that be physically connected to this AC power equipment, thus when testing, very inconvenience, work efficiency can't promote.
Therefore, in order to overcome the inconvenience of adopting the entity load to connect in the common technology, so the research and development of alternating current electronic load analogue means are arranged.Yet, in general alternating current electronic load analogue means commonly used, generally only be used for the test of electric heater bulb constant resistance load, and be not suitable for the test of inductive or capacity load, also be not suitable for the current waveform test of compositeness load.And declare to do in fact when testing, problems such as electromagnetic interference (EMI) can be arranged all in the alternating current electronic load analogue means commonly used of inductance life or capacitive character test in part.
Therefore, fundamental purpose of the present invention provides a kind of circuit design of alternating current electronic load analogue means, and it can be simulated various resistive, inductive, reach the alternating current electronic load analogue means of different AC load characteristics such as capacitive character.The present invention is suitable for testing various AC power, for example uninterrupted power supply (UPS), phase inverter (INVERTER), voltage stabilizer (VOLTAGE REGULATOR), amplifier AC power equipment such as (AMPLIFIER).
Another object of the present invention provides a kind of alternating current electronic load analogue means that can adjust the load form arbitrarily.In the present invention, with phase control produce one with supply voltage homophase, backwardness or leading Current Control waveform, cooperate members such as electric current and voltage phase-control circuit, on-off circuit, rectification circuit, voltage-to-current conversion circuit again, and can simulate the current waveform of any compositeness load, comprise that rectified load, rectification and inductive are compound, rectification and capacitive character are compound etc., and the current waveform positive-negative half-cycle symmetry of simulation.Aspect power factor (PF), controllable power factor (PF) reaches-1.000～0～+ 1.000.
Purpose of the present invention can realize by following mode, a kind of alternating current electronic load analogue means of the present invention, it is characterized in that including: a voltage zero-crossing is got over circuit for detecting, two input ends are that cross-over connection is in AC power, with when the positive half cycle of each cycle of AC power, send a metering pulses by its output terminal; One current waveform produces circuit, and receive this voltage zero-crossing and get over the metering pulses that circuit for detecting produces, and the setting of foundation one current phase initialization circuit, produce a phase control signal; One electric current and voltage phase-control circuit receives this current waveform generation phase control signal and voltage zero-crossing that circuit produced respectively and gets over the metering pulses that circuit for detecting produces, and produces first and second switch controlling signal by its output terminal; One on-off circuit, it includes four change-over switches, wherein first change-over switch and the 4th change-over switch are to be configuration, controlled by first switch controlling signal of this electric current and voltage phase-control circuit, and second change-over switch and the 3rd change-over switch are to be configuration, controlled by the second switch control signal of this electric current and voltage phase-control circuit; One rectification circuit is attempted by two output terminals of this on-off circuit, and the AC power that on-off circuit is sent gives rectification, produces a direct current voltage at output terminal; One voltage-to-current conversion circuit is connected the output terminal of rectification circuit, and under the control of phase control signal, the DC voltage that this rectification circuit is exported is converted to a load current.More include the accurate position of electric current control circuit, be connected the output terminal that current waveform produces circuit, in order to regulate the signal level of this current waveform generation phase control waveform that circuit produced.This AC power electric current is the voltage homophase with AC power.This AC power electric current is voltage one phasing degree of backward or leading AC power.
Below will cooperate preferred embodiment circuit diagram of the present invention and oscillogram, the present invention is further illustrated as after, wherein:
Description of drawings:
Fig. 1 is a preferred embodiment circuit diagram of the present invention;
Fig. 2 is the oscillogram of the present invention's each interdependent node when simulating pure resistive loads;
The oscillogram of each interdependent node when Fig. 3 is the load of analog electrical of the present invention perception;
Fig. 4 is the oscillogram of the present invention's each interdependent node when the artificial capacitor load.
Description of drawings:
1 ... AC power 2 ... on-off circuit
3 ... rectification circuit 4 ... voltage-to-current conversion circuit
5 ... voltage zero-crossing is got over circuit for detecting 6 ... current waveform produces circuit
61 ... current phase initialization circuit 7 ... the accurate position of electric current control circuit
71 ... the accurate position setting circuit 8 of electric current ... the electric current and voltage phase-control circuit
As shown in Figure 1, be circuit diagram of the present invention.Alternating current electronic load analogue means of the present invention mainly includes that an on-off circuit 2, a rectification circuit 3, a voltage-to-current conversion circuit 4, a voltage zero-crossing are got over circuit for detecting 5, a current waveform produces circuit 6, a current phase initialization circuit 61, the accurate position of electric current control circuit 7, the accurate position setting circuit 71 of an electric current, an electric current and voltage phase-control circuit 8.
Wherein on-off circuit 2 is that cross-over connection is in AC power 1, it includes four change-over switch SWA～SWD, wherein the first change-over switch SWA and the 4th change-over switch SWD are configuration, and the first switch controlling signal SWAD that exported by electric current and voltage phase-control circuit 8 controls; And the second change-over switch SWB and the 3rd change-over switch SWC are configuration, and the second switch control signal SWBC that exported by electric current and voltage phase-control circuit 8 controls.So, can form a loop via the first change-over switch SWA and the 4th change-over switch SWD as the voltage VS of AC power 1 during at positive half cycle; And, can form a loop via the 3rd change-over switch SWC and the second change-over switch SWB as the voltage VS of AC power 1 during at negative half period.
Rectification circuit 3 is two output terminals that are attempted by this on-off circuit 2, gives rectification in order to the alternating voltage VL that on-off circuit 2 is sent, to produce a direct current voltage VD at output terminal.These rectification circuit 3 inside include four diodes, form a full-wave rectifying circuit.
Voltage-to-current conversion circuit 4 is connected the output terminal of rectification circuit 3, and under the control of phase control signal, the DC voltage VD that this rectification circuit 3 is exported is converted to a load current IL.
Two input ends that voltage zero-crossing is got over circuit for detecting 5 are that cross-over connection is in AC power 1, whenever the phase angle of this AC power 1 is 0 o'clock, can be detected by this circuit for detecting 5, and when AC power 1 is whenever sent a cycle, can send a metering pulses to output terminal by the output terminal that voltage zero-crossing is got over circuit for detecting 5.So can get over a string metering pulses VA of output terminal generation of circuit for detecting 5 at this voltage zero-crossing.
Current waveform produces circuit 6 and receives these voltage zero-crossings and get over the metering pulses VA that circuit for detecting produces, and according to the setting of current phase initialization circuit 61, produce one with voltage VS homophase, backwardness or the leading phase control signal VP of AC power.In an embodiment of the present invention, the inside that this current waveform produces circuit 6 can include a waveform information memory body, counter and numeral to analogy converter, by this circuit structure, can be easy to produce required and AC supply voltage VS homophase, backwardness or leading output waveform.
The phase control signal VP that this current waveform generation circuit 6 is produced can be again via the accurate position of electric current control circuit, in order to regulate the signal level of this phase control signal VP.This function in fact promptly is to set the accurate position of required load current.
Two input ends of electric current and voltage phase-control circuit 8 receive this current waveform respectively and produce phase control signal VP and the voltage zero-crossing that circuit 6 produced and get over the metering pulses VA that circuit for detecting 5 is produced, and produce the first switch controlling signal SWAD and second switch control signal SWBC by its output terminal.
Because AC load may be the load of different qualities such as resistive, inductive, capacitive character, so when simulation one electronic load, must want to meet these characteristics, demand that could be realistic, below will be respectively with pure resistive, inductive, the explanation of capacitive load characteristic as after.
One, resistive load:
The characteristic of resistive load is electric current and voltage homophase.Therefore, required in this inventionly to produce an alternating current IS with AC supply voltage VS homophase.Now consult the circuit of Fig. 1 and waveform shown in Figure 2 simultaneously, be described as follows:
Two input ends that voltage zero-crossing is got over circuit for detecting 5 be cross-over connection in AC power 1, and can send the metering pulses VA of a sequence at its output terminal.Metering pulses VA delivers to current waveform and produces after the circuit 6 owing to be the resistive load of analog electrical, so the time this current phase initialization circuit 61 be to be set at resistive.Therefore, this current waveform produces circuit 6 promptly can be according to the setting of current phase initialization circuit 61, and produce one with the phase control waveform VP of AC supply voltage VS homophase.
This phase control waveform VP and metering pulses VA can deliver in the electric current and voltage phase-control circuit 8 simultaneously, and the output terminal by electric current and voltage phase-control circuit 8 produces one group of switch controlling signal SWAD, SWBC again.In order to obtain this switch controlling signal SWAD, SWBC, this electric current and voltage phase-control circuit 8 can adopt general known logical circuit (for example mutual exclusion or lock) to design.
Switch controlling signal SWAD promptly is used for the first change-over switch SWA, and the on off state of the 4th change-over switch SWD in the gauge tap circuit 2; And switch controlling signal SWBC promptly is used for the second change-over switch SWB, and the on off state of the 3rd change-over switch SWC in the gauge tap circuit 2.
When resistive load, this switch controlling signal SWAD is that perseverance is high state, and switch controlling signal SWBC is the permanent low state that is.Therefore, can produce a voltage waveform VL identical at the output terminal of on-off circuit 2 with the voltage VS of AC power.This voltage waveform VL can do full-wave rectification via rectification circuit 3, and has produced a rectification output waveform VD.
This rectification output waveform VD delivers to the two ends of voltage-to-current conversion circuit 4, then, cooperates the control of aforementioned phase control signal VP ' again, makes this voltage-to-current conversion circuit 4 produce a load current 11.After obtaining this load current IL, because its phase place is the voltage VS homophase with AC power, so in fact promptly be to obtain one and the source current IS of AC supply voltage VS homophase at the AC power end.
Two, lagging load
The characteristic of inductive load is that electric current falls behind a certain phasing degree of voltage.Therefore, the alternating current IS that will produce an a certain phasing degree of backward AC supply voltage VS required in this invention.When lagging load, each waveform correlation as shown in Figure 3.
Two input ends that voltage zero-crossing is got over circuit for detecting 5 be cross-over connection in AC power 1, and can send the metering pulses VA of a sequence at certain output terminal.Metering pulses VA delivers to current waveform and produces after the circuit 6 owing to be the load of analog electrical perception, so the time this current phase initialization circuit 61 be to be set at inductive.Therefore, this current waveform produces circuit 6 promptly can be according to the setting of current phase initialization circuit 61, and produces a phase control waveform VP who lags behind a certain angle θ of AC supply voltage VS.
This phase control waveform VP and metering pulses VA can deliver in the electric current and voltage phase-control circuit 8 simultaneously, and the output terminal by electric current and voltage phase-control circuit 8 produces one group of switch controlling signal SWAD, SWBC again.
This phase control waveform VP and metering pulses VA can deliver in the electric current and voltage phase-control circuit 8 simultaneously, and the output terminal by electric current and voltage phase-control circuit 8 produces one group of switch controlling signal SWAD, SWBC again.
This switch controlling signal SWAD promptly is used for the first change-over switch SWA, and the on off state of the 4th change-over switch SWD in the gauge tap circuit 2; And switch controlling signal SWBC promptly is used for the second change-over switch SWB, and the on off state of the 3rd change-over switch SWC in the gauge tap circuit 2.
When inductive load, the sequential relationship of this switch controlling signal SWAD and SWBC as shown in Figure 3.The result of each change-over switch SWA in switch controlling signal SWAD and SWBC gauge tap circuit 2～SWD action makes the output terminal of this on-off circuit 2 produce voltage waveform VL.For example, be example with first cycle, when the first and the 4th change-over switch SWA and SWD closure and second and third change-over switch SWB and SWC by the time, the voltage VS of AC power 1 is delivered to the input end of rectification circuit 3.And grand to 0 the time as the voltage VS of AC power 1, the first and the 4th change-over switch SWA and SWD are by, second and third change-over switch SWB and SWC closure.During this period, produce the voltage waveform VL ' of a forward at the output terminal of this on-off circuit 2.
Then, when the phase place of electric current was 0, the first and the 4th change-over switch SWA, SWD were closed once again, and second and third change-over switch SWB, SWC then open a way, so the negative half period of this AC supply voltage VS appears at the output terminal of this on-off circuit 2.With this similar operating principle, and obtain as shown in the figure voltage waveform VL at the output terminal of on-off circuit 2.
After above-mentioned waveform processing, this voltage waveform VL does full-wave rectification via rectification circuit 3 again, and has produced a rectification output waveform VD.
This rectification output waveform VD delivers to the two ends of voltage-to-current conversion circuit 4, then, cooperates the control of aforementioned phase control signal VP again, makes this voltage-to-current conversion circuit 4 produce a load current IL.After obtaining this load current IL, because its phase place is the voltage VS one phasing degree θ that falls behind AC power, so in fact promptly be to obtain a source current IS who lags behind a certain phasing degree of AC supply voltage VS at the AC power end.
Three, capacity load
The characteristic of capacity load is a certain phasing degree of electric current leading voltage.Therefore, the alternating current IS that will produce an a certain phasing degree of leading AC supply voltage VS required in this invention.When capacity load, each waveform correlation as shown in Figure 4.
Two input ends that voltage zero-crossing is got over circuit for detecting 5 be cross-over connection in AC power 1, and can send the metering pulses VA of a sequence at its output terminal.Metering pulses VA delivers to current waveform and produces after the circuit 6 owing to be the load of analog electrical capacitive, so the time this current phase initialization circuit 61 be to be set at capacitive character.Therefore, this current waveform produces circuit 6 promptly can be according to the setting of current phase initialization circuit 61, and produces a phase control waveform VP who is ahead of a certain angle θ of AC supply voltage VS.
This phase control waveform VP and metering pulses VA can deliver in the electric current and voltage phase-control circuit 8 simultaneously, and the output terminal by electric current and voltage phase-control circuit 8 produces one group of switch controlling signal SWAD, SWBC again.
This phase control waveform VP and metering pulses VA can deliver in the electric current and voltage phase-control circuit 8 simultaneously, and the output terminal by electric current and voltage phase-control circuit 8 produces one group of switch controlling signal SWAD, SWBC again.
This switch controlling signal SWAD promptly is used for the first change-over switch SWA, and the on off state of the 4th change-over switch SWD in the gauge tap circuit 2; And switch controlling signal SWBC promptly is used for the second change-over switch SWB, and the on off state of the 3rd change-over switch SWC in the gauge tap circuit 2.
When capacity load, the sequential relationship of this switch controlling signal SWAD and SWBC as shown in Figure 4.The result of each change-over switch SWA in switch controlling signal SWAD and SWBC gauge tap circuit 2～SWD action makes the output terminal of this on-off circuit 2 produce a voltage waveform VL.For example, be example with first cycle, when the first and the 4th change-over switch SWA and SWD closure, the voltage VS of AC power 1 is delivered to the input end of rectification circuit 3.And when the voltage VS of AC power 1 reduces to a certain magnitude of voltage (when current value is 0), the first and the 4th change-over switch SWA, SWD end, change by second and third change-over switch SWB, SWC closure, so can produce the waveform VL ＂ of a negative sense at the output terminal of this on-off circuit 2.
Then, after the voltage VS of AC power 1 arrived null value, the first and the 4th change-over switch SWA, SWD were closed once again, and second and third change-over switch SWB, SWC then open a way.So the negative half period of this AC supply voltage VS appears at the output terminal of this on-off circuit 2.With this similar operating principle, and obtain as shown in the figure voltage waveform VL at the output terminal of on-off circuit 2.
After above-mentioned waveform processing, this voltage waveform VL does full-wave rectification via rectification circuit 3 again, and has produced a rectification output waveform VD.
This rectification output waveform VD delivers to the two ends of voltage-to-current conversion circuit 4, then, cooperates the control of aforementioned phase control signal VP again, makes this voltage-to-current conversion circuit 4 produce a load current IL.After obtaining this load current IL, because its phase place is the voltage VS one phasing degree θ of leading AC power, so in fact promptly be to obtain one at the AC power end to be ahead of a certain source current IS that wants parallactic angle of AC supply voltage VS.
Claims (5)
1, a kind of alternating current electronic load analogue means is characterized in that including:
One voltage zero-crossing is got over circuit for detecting, two input ends be cross-over connection in AC power, with when the positive half cycle of each cycle of AC power, send a metering pulses by its output terminal;
One current waveform produces circuit, and receive this voltage zero-crossing and get over the metering pulses that circuit for detecting produces, and the setting of foundation one current phase initialization circuit, produce a phase control signal;
One electric current and voltage phase-control circuit receives this current waveform generation phase control signal and voltage zero-crossing that circuit produced respectively and gets over the metering pulses that circuit for detecting produces, and produces first and second switch controlling signal by its output terminal;
One on-off circuit, it includes four change-over switches, wherein first change-over switch and the 4th change-over switch are to be configuration, controlled by first switch controlling signal of this electric current and voltage phase-control circuit, and second change-over switch and the 3rd change-over switch are to be configuration, controlled by the second switch control signal of this electric current and voltage phase-control circuit;
One rectification circuit is attempted by two output terminals of this on-off circuit, and the AC power that on-off circuit is sent gives rectification, produces a direct current voltage at output terminal;
One voltage-to-current conversion circuit is connected the output terminal of rectification circuit, and under the control of phase control signal, the DC voltage that this rectification circuit is exported is converted to a load current.
2, alternating current electronic load analogue means as claimed in claim 1, it is characterized in that: more include the accurate position of electric current control circuit, be connected the output terminal of current waveform generation circuit, in order to regulate the signal level of this current waveform generation phase control waveform that circuit produced.
3, alternating current electronic load analogue means as claimed in claim 1 is characterized in that: this AC power electric current is the voltage homophase with AC power.
4, alternating current electronic load analogue means as claimed in claim 1 is characterized in that: this AC power electric current is voltage one phasing degree that falls behind AC power.
5, alternating current electronic load analogue means as claimed in claim 1 is characterized in that: voltage one phasing degree that this AC power electric current is leading AC power.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB981246982A CN1137536C (en) | 1998-11-06 | 1998-11-06 | A. C. electron load simulator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB981246982A CN1137536C (en) | 1998-11-06 | 1998-11-06 | A. C. electron load simulator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1259674A true CN1259674A (en) | 2000-07-12 |
| CN1137536C CN1137536C (en) | 2004-02-04 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB981246982A Expired - Fee Related CN1137536C (en) | 1998-11-06 | 1998-11-06 | A. C. electron load simulator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1137536C (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1300922C (en) * | 2002-07-30 | 2007-02-14 | 台达电子工业股份有限公司 | Synchronous rectificating device |
| CN100443906C (en) * | 2002-03-26 | 2008-12-17 | Abb瑞士有限公司 | Quasi-true examination for current mutual-inductor in substation |
| CN100462727C (en) * | 2004-02-24 | 2009-02-18 | 博计电子股份有限公司 | Simulator of AC electronic load suitable to any waveform of AC signal |
| CN101206249B (en) * | 2006-12-22 | 2010-09-29 | 鸿富锦精密工业（深圳）有限公司 | Electronic load device |
| CN101963635B (en) * | 2009-07-23 | 2012-07-04 | 中达电通股份有限公司 | Method and system for judging AC load characteristics as well as light-dimming energy-saving controller |
| CN102915059A (en) * | 2011-08-04 | 2013-02-06 | 特克特朗尼克公司 | Means of providing variable reactive load capability on an electronic load |
| CN104360113A (en) * | 2014-11-24 | 2015-02-18 | 成都唯昂新材料有限公司 | Electronic load device |
| CN113253005A (en) * | 2020-02-07 | 2021-08-13 | 群光电能科技股份有限公司 | Load recognition system |
-
1998
- 1998-11-06 CN CNB981246982A patent/CN1137536C/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100443906C (en) * | 2002-03-26 | 2008-12-17 | Abb瑞士有限公司 | Quasi-true examination for current mutual-inductor in substation |
| CN1300922C (en) * | 2002-07-30 | 2007-02-14 | 台达电子工业股份有限公司 | Synchronous rectificating device |
| CN100462727C (en) * | 2004-02-24 | 2009-02-18 | 博计电子股份有限公司 | Simulator of AC electronic load suitable to any waveform of AC signal |
| CN101206249B (en) * | 2006-12-22 | 2010-09-29 | 鸿富锦精密工业（深圳）有限公司 | Electronic load device |
| CN101963635B (en) * | 2009-07-23 | 2012-07-04 | 中达电通股份有限公司 | Method and system for judging AC load characteristics as well as light-dimming energy-saving controller |
| CN102915059A (en) * | 2011-08-04 | 2013-02-06 | 特克特朗尼克公司 | Means of providing variable reactive load capability on an electronic load |
| CN104360113A (en) * | 2014-11-24 | 2015-02-18 | 成都唯昂新材料有限公司 | Electronic load device |
| CN113253005A (en) * | 2020-02-07 | 2021-08-13 | 群光电能科技股份有限公司 | Load recognition system |
| CN113253005B (en) * | 2020-02-07 | 2024-01-12 | 群光电能科技股份有限公司 | Load identification system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1137536C (en) | 2004-02-04 |
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