CN104198781B - A kind of method and device for controlling AC signal to export - Google Patents
A kind of method and device for controlling AC signal to export Download PDFInfo
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- CN104198781B CN104198781B CN201410453882.7A CN201410453882A CN104198781B CN 104198781 B CN104198781 B CN 104198781B CN 201410453882 A CN201410453882 A CN 201410453882A CN 104198781 B CN104198781 B CN 104198781B
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Abstract
The invention discloses a kind of method and device for controlling AC signal to export, obtain pulse signal, the cycle of the pulse signal and the cycle phase of the AC signal are same, and the first phase angle value at the time of pulse signal changes to the second amplitude by first amplitude with the AC signal is corresponding；According to the first phase angle value and the cycle of the AC signal, the phase angle for calculating the AC signal is changed to the interval time of preset phase angle value by the first phase angle value；Since the timing detecting at the time of the pulse signal changes to the second amplitude by first amplitude, after the interval time, controlling the AC signal output.The present invention solves the defect of traditional method of testing, can control the starting phase angle of AC signal output voltage, improves the efficiency of test and the accuracy of test result.
Description
Technical field
The present invention relates to electricity field, more particularly to a kind of method and device for controlling AC signal to export.
Background technology
The R＆D process of Switching Power Supply is related to the project much tested, such as available machine time, retention time and surge current.And
The test value of available machine time, retention time and surge current depend not only on the size of AC signal output voltage virtual value,
Additionally depend on the starting phase angle of output voltage.
Available machine time is most long when the starting phase angle of AC signal output voltage is 0 or 180 degree, at 90 or 270 degree
It is most short.The test available machine time needs just measure the maximum duration of start when starting phase angle is 0 or 180 degree.And switch electricity
The retention time in source is most short when the starting phase angle of output voltage is 0 or 180 degree, most long at 90 or 270 degree.Test is kept
Time needs just measure the most short retention time when starting phase angle is 0 or 180 degree.Most Switching Power Supply is due to depositing
In the input filter capacitor that capacity is larger, booting moment produces very big peak point current, i.e. surge current.Surge current is in exchange
The starting phase angle of signal output voltage reaches maximum when being 90 or 270 degree, it is therefore desirable to switch power source output voltage
Starting phase angle is measured when being 90 or 270 degree, otherwise will influence the accuracy of measurement.
But, traditional method of testing has no idea to control the starting phase angle of AC signal output voltage, can only be not
The switching on and shutting down stopped, play at some game of chance to realize, reduce the efficiency of test.Simultaneously as exchange letter can not be more accurately controlled
The starting phase angle of number output voltage, when measuring each project, does not ensure that AC signal in the phase required for correspondence
Exported during angle, so as to cause test result to there is larger error.
The content of the invention
It is an object of the invention to provide a kind of method and device for controlling AC signal to export, it is therefore intended that solves conventional measurement
In examination because cause testing efficiency low can not controlling the starting phase angle of AC signal output voltage and test result exist it is larger
The problem of error.
In order to solve the above technical problems, the invention provides a kind of method for controlling AC signal output, including：
Pulse signal is obtained, the cycle of the pulse signal and the cycle phase of the AC signal are same, the pulse signal
First phase angle value at the time of changing to the second amplitude by first amplitude with the AC signal is corresponding；
According to the first phase angle value and the cycle of the AC signal, the phase angle of the AC signal is calculated by institute
State the interval time that first phase angle value changes to preset phase angle value；
The timing since detecting at the time of the pulse signal changes to the second amplitude by first amplitude, by described
After interval time, the AC signal output is controlled.
Wherein, the acquisition pulse signal includes：The AC signal is converted into pulse signal.
Wherein, the pulse signal is square-wave signal.
Wherein, it is corresponding for square-wave signal trailing edge at the time of the pulse signal changes to the second amplitude by first amplitude
Moment.
Wherein, preset phase angle is changed to by the first phase angle value at the phase angle for calculating the AC signal
Before the interval time of value, in addition to：
The cycle of the square-wave signal is calculated, the cycle of the square-wave signal is the cycle of the AC signal.
Wherein, preset phase angle is changed to by the first phase angle value at the phase angle for calculating the AC signal
Before the interval time of value, in addition to：Receive the preset phase angle value.
Wherein, in addition to：Show the preset phase angle value.
Present invention also offers a kind of device for controlling AC signal to export, including：Acquisition module, processing computing module with
And output control module, wherein：
The acquisition module, for obtaining pulse signal, the cycle of the pulse signal and the cycle of the AC signal
It is identical, with the first phase angle value phase of the AC signal at the time of pulse signal changes to the second amplitude by first amplitude
Correspondence；
The processing computing module, for the cycle according to the first phase angle value and the AC signal, calculates institute
The phase angle for stating AC signal is changed to the interval time of preset phase angle value by the first phase angle value；
The control output module, for from detect the pulse signal by first amplitude change to the second amplitude when
Carve and start timing, after the interval time, controlling the AC signal output.
Wherein, the acquisition module includes：
The AC signal is converted to component in the waveform changing circuit of square-wave signal, the waveform changing circuit
Annexation includes：
Resistance R1, resistance R2 connect with resistance R3, and diode D1 is in parallel after being connected with light emitting diode with resistance R2, institute
The negative electrode for stating diode D1 is connected with the anode of the light emitting diode, and light emitting diode constitutes isolation circuit with phototriode
U1, the colelctor electrode of the phototriode is connected with power supply, and emitter stage is grounded after being connected with resistance R4 and resistance R5, triode Q1
Base stage be connected to the resistance R4 and resistance R5 centre, the colelctor electrode of the triode Q1 connected with resistance R6 after with power supply
It is connected, the grounded emitter of the triode Q1.
Wherein, the control output module is used to change to the second amplitude from detecting the pulse signal by first amplitude
At the time of start timing and include：
Since the control output module specifically for the timing detecting at the time of the square-wave signal trailing edge is corresponded to.
Wherein, in addition to：Receiving module, for receiving the preset phase angle value.
Wherein, in addition to：Display module, for showing the preset phase angle value.
A kind of method and device for controlling AC signal to export provided by the present invention, obtains the week with the AC signal
Phase identical pulse signal because at the time of the pulse signal changes to the second amplitude by first amplitude with the AC signal
First phase angle value it is corresponding, so according to the first phase angle value and the cycle of the AC signal, can calculate
The phase angle of the AC signal is changed to the interval time of preset phase angle value by the first phase angle value, thus will be pre-
If the angle difference of phase angle and first phase angle value is converted to the spacing value on output time, therefore from detecting the arteries and veins
Timing rushing at the time of signal changes to the second amplitude by first amplitude, after the interval time, AC signal
Phase angle is just preset phase angle, now controls AC signal output, and the original phase angle values of the AC signal of output are
Preset phase angle value.It can thus be seen that the present invention solves the defect of traditional method of testing, AC signal can be controlled defeated
Go out the starting phase angle of voltage, improve the efficiency of test and the accuracy of test result.
Brief description of the drawings
Fig. 1 is a kind of flow chart of control AC signal output intent disclosed in the embodiment of the present invention；
Fig. 2 is the flow chart of another control AC signal output intent disclosed in the embodiment of the present invention；
Fig. 3 is the circuit diagram of another control AC signal output intent disclosed in the embodiment of the present invention；
Fig. 4 is the partial circuit diagram of another control AC signal output intent disclosed in the embodiment of the present invention；
Fig. 5 is that another control AC signal output intent is illustrated in the waveform of A points and B points disclosed in the embodiment of the present invention
Figure；
Fig. 6 is the structural representation of the disclosed control AC signal output device of the embodiment of the present invention.
Embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present application, the technical scheme in the embodiment of the present application is carried out clear, complete
Site preparation is described, it is clear that described embodiment is only some embodiments of the present application, rather than whole embodiments.It is based on
Embodiment in the application, it is every other that those of ordinary skill in the art are obtained under the premise of creative work is not made
Embodiment, belongs to the scope of the application protection.
The invention provides it is a kind of control AC signal output intent embodiment, as shown in figure 1, the embodiment include with
Lower step：
S101：Obtain pulse signal.
The cycle of the pulse signal acquired and the cycle phase of the AC signal are same, and the pulse signal is by first
Amplitude changes to corresponding with the first phase angle value of the AC signal at the time of the second amplitude.
S102：When the phase angle for calculating the AC signal changes to the interval of preset phase angle value by first phase angle value
Between.
According to the first phase angle value and the cycle of the AC signal, the phase angle of the AC signal is calculated by institute
State the interval time that first phase angle value changes to preset phase angle value；
S103：The timing since detecting at the time of the pulse signal changes to the second amplitude by first amplitude, in warp
Cross after the interval time, control the AC signal output.
A kind of method for controlling AC signal output is present embodiments provided, acquisition and the cycle phase of the AC signal are same
Pulse signal because with the first of the AC signal at the time of pulse signal changes to the second amplitude by first amplitude
Phase angle is corresponding, so according to the first phase angle value and the cycle of the AC signal, can calculate the friendship
The phase angle of stream signal is changed to the interval time of preset phase angle value by the first phase angle value, thus by preset phase
The angle difference of angle value and first phase angle value is converted to the spacing value on output time, therefore from detecting the pulse signal
Timing at the time of changing to the second amplitude by first amplitude, after the interval time, the phase angle of AC signal
It is just preset phase angle, now controls AC signal output, the original phase angle values of the AC signal of output are default phase
Parallactic angle value.It can thus be seen that the present invention solves the defect of traditional method of testing, AC signal output voltage can be controlled
Starting phase angle, improve the efficiency of test and the accuracy of test result.
The invention provides a kind of another embodiment of control AC signal output intent, Fig. 2 and Fig. 3 are refer to, Fig. 2 is
The flow chart of the another embodiment of the application, Fig. 3 is the circuit diagram of the another embodiment of the application, and the embodiment comprises the following steps：
S201：AC sine signal is converted into square-wave signal.
Fig. 4 is refer to, AC sine signal is reduced voltage by R1, R2 and R3 partial pressure, D1 is used for one-way conduction, U1
For isolating.When R1 ends is just, R3 ends are the high electricity of transistor emitter output inside negative, the diode current flow inside U1, U1
Flat, Q1 conductings, Q1 colelctor electrode output is low.When R1 ends are negative, R3 ends is just, D1 end, the diode reverse cut-off inside U1,
Transistor emitter output inside triode cut-off inside U1, U1 is low, and Q1 cut-offs, Q1 colelctor electrodes output is high.Utilize D1's
One-way conduction characteristic, can be converted to AC sine signal (A points waveform) square-wave signal (B points waveform), as shown in Figure 5.It is described
The cycle phase of AC sine signal and the square-wave signal is same, and the rising edge and trailing edge of the square-wave signal correspond to institute respectively
State 0 degree of phase angle of AC sine signal and 180 degree phase angle.By taking trailing edge as an example, the trailing edge of the square-wave signal with
The AC signal 180 degree phase angle is corresponding.
The existing method that AC signal is converted into square-wave signal is a lot, however it is not limited to such a method, as long as can realize
The method of the function, this does not affect the realization of the present invention.
In addition, the pulse signal that the present embodiment is acquired is specially square-wave signal, it is necessary to which explanation, other can expire
The pulse signal of sufficient condition can similarly realize the present invention, it should be not limited to such a square-wave signal.
S202：The frequency of alternating current is calculated, the cycle is calculated by frequency.
Its frequency is calculated by the obtained square-wave signals of step S201, and then obtains the frequency of the AC signal.
The frequency for obtaining AC signal can also be calculated in the step by gathering the voltage of AC signal.If using
Such a method, then step S202 can be exchanged with step S201 order, have no effect on the present invention realization.But pass through square wave
The method for calculating frequency can be simpler.
S203：The phase angle for calculating the AC sine signal changes to preset phase angle value by 180 degree phase angle
Interval time.
According to the first phase angle value and the cycle of the AC signal, the phase angle of the AC sine signal is calculated
The interval time of preset phase angle value is changed to by 180 degree phase angle.For example, a complete sine wave is 360 degree, if
It is 1Hz to calculate obtained frequency.So the cycle is 1s.When preset phase angle value is 270 degree, it can be obtained with reference to Fig. 5, it is described to hand over
The phase angle of stream signal is needed by a quarter cycle, i.e. 0.25s when changing to 270 degree by 180 degree.
S204:When CPU detects the trailing edge of the square wave, start timer and start timing, pass through the interval
After time, the AC signal output is controlled.
As shown in figure 5, when phase angle is 180 degree, there is trailing edge in square wave.Now the CPU in single-chip microcomputer is detected
Trailing edge, starts to start timer timing, when the time of CPU timing is 0.25s, outputs signal to Q2, Q2 driving relays
Closure, makes output end export AC signal.The starting phase angle of the AC signal now exported is preset phase angle value 270
Degree.
Alternatively, the reception to the preset phase angle value is also included before step S203.
In addition, the present embodiment also includes showing the preset phase angle value, so user can be avoided to forget to set
The preset phase angle numerical value put, influences the work of next step.Certainly, do not show that the preset phase angle value is also possible,
The realization of the present invention is not interfered with.
The embodiment of the present application can be used for the survey to available machine time, retention time and surge current in Switching Power Supply R＆D process
Examination., it is necessary to test its most long available machine time such as when testing the available machine time of Switching Power Supply, and in output voltage starting phase angle
The available machine time is most long during for 0 or 180 degree, and this is accomplished by controlling AC signal to export when phase angle is 0 or 180 degree.Utilize this
Apply for the method that embodiment is provided, the output of the AC signal at respective phase angle can be controlled, it is to avoid multiple switching machine is carried out
Test, improves the efficiency of test.Meanwhile, this method can more be accurately controlled the initial phase of AC signal output voltage
Angle, ensure that AC signal, in the phase angle output required for correspondence, improves the accuracy rate of test result in test.
As shown in fig. 6, present invention also offers a kind of embodiment of control AC signal output device, including：
Acquisition module 100, for obtaining pulse signal, the cycle of the pulse signal and the cycle phase of the AC signal
Together, it is relative with the first phase angle value of the AC signal at the time of pulse signal changes to the second amplitude by first amplitude
Should；
Computing module 200 is handled, for the cycle according to the first phase angle value and the AC signal, calculates described
The phase angle of AC signal is changed to the interval time of preset phase angle value by the first phase angle value；
Control output module 300, for from detect the pulse signal by first amplitude change to the second amplitude when
Carve and start timing, after the interval time, controlling the AC signal output.
A kind of device for controlling AC signal to export provided by the present invention, the device obtains the week with the AC signal
Phase identical pulse signal because at the time of the pulse signal changes to the second amplitude by first amplitude with the AC signal
First phase angle value it is corresponding, so according to the first phase angle value and the cycle of the AC signal, can calculate
The phase angle of the AC signal is changed to the interval time of preset phase angle value by the first phase angle value, thus will be pre-
If the angle difference of phase angle and first phase angle value is converted to the spacing value on output time, therefore from detecting the arteries and veins
Timing rushing at the time of signal changes to the second amplitude by first amplitude, after the interval time, AC signal
Phase angle is just preset phase angle, now controls AC signal output, and the original phase angle values of the AC signal of output are
Preset phase angle value.It can thus be seen that the present invention solves the defect of traditional method of testing, AC signal can be controlled defeated
Go out the starting phase angle of voltage, improve the efficiency of test and the accuracy of test result.
A kind of another embodiment for controlling AC signal output device provided by the present invention is as shown in Figure 4.In embodiment
In, the acquisition module includes the waveform changing circuit that AC sine signal is converted to square-wave signal, the waveform conversion electricity
The annexation of component includes in road：
Resistance R1, resistance R2 connect with resistance R3, and diode D1 is in parallel after being connected with light emitting diode with resistance R2, institute
The negative electrode for stating diode D1 is connected with the anode of the light emitting diode, and light emitting diode constitutes isolation circuit with phototriode
U1, the colelctor electrode of the phototriode is connected with power supply, and emitter stage is grounded after being connected with resistance R4 and resistance R5, triode Q1
Base stage be connected to the resistance R4 and resistance R5 centre, the colelctor electrode of the triode Q1 connected with resistance R6 after with power supply
It is connected, the grounded emitter of the triode Q1.
The processing computing module is specifically as follows single-chip microcomputer (MCU), and the single-chip microcomputer includes CPU, for detecting square wave
Trailing edge.It is pointed out that trailing edge can also be rising edge herein, herein only by taking trailing edge as an example.
The output control module includes timer, relay and Q2, and the timer is used to detect trailing edge in CPU
When start timing, the relay and Q2 are used for the output for controlling AC signal.
The device also includes receiving module and display module (being not drawn into figure), for being carried out to the preset phase angle value
Receive and display.
The operation principle of circuit described in the present embodiment is：The AC sine signal of input is divided into two-way synchronizing signal, led to
Road one is converted to square-wave signal through acquisition module and is sent to single-chip microcomputer (MCU) as AC signal to be output, path two, and MCU passes through
Square wave calculates the frequency of AC sine signal, and its cycle is calculated by frequency, and the preset phase angle is obtained further according to the cycle
The interval time of value phase angle corresponding with the trailing edge, timer starts timing when CPU detects trailing edge, through institute
State after time interval, the AC signal to be output output in Q2 driving relay closures, control access one.
The method and device to control AC signal output provided by the present invention is described in detail above.Herein
Apply specific case to be set forth the principle and embodiment of the present invention, the explanation of above example is only intended to help
Understand the method and its core concept of the present invention.It should be pointed out that for those skilled in the art, not taking off
On the premise of from the principle of the invention, some improvement and modification can also be carried out to the present invention, these are improved and modification also falls into this
In invention scope of the claims.
Claims (7)
1. a kind of method for controlling AC signal output, it is characterised in that including：
Pulse signal is obtained, the cycle phase of the cycle of the pulse signal and the AC signal is same, the pulse signal is by the
One amplitude changes to corresponding with the first phase angle value of the AC signal at the time of the second amplitude；Wherein, the acquisition arteries and veins
Rushing signal includes：AC sine signal is converted to by waveform changing circuit first in square-wave signal, the waveform changing circuit
The annexation of device includes：
Resistance R1, resistance R2 connect with resistance R3, and diode D1 is in parallel after being connected with light emitting diode with resistance R2, and described two
Pole pipe D1 negative electrode is connected with the anode of the light emitting diode, and light emitting diode constitutes isolation circuit U1 with phototriode,
The colelctor electrode of the phototriode is connected with power supply, and emitter stage is grounded after being connected with resistance R4 and resistance R5, triode Q1's
Base stage is connected to the resistance R4 and the resistance R5 centre, the colelctor electrode of the triode Q1 connected with resistance R6 after with electricity
Source is connected, the grounded emitter of the triode Q1；
Receive preset phase angle value；
According to the first phase angle value and the cycle of the AC signal, the phase angle of the AC signal is calculated by described the
One phase angle changes to the interval time of the preset phase angle value；
Since the timing detecting at the time of the pulse signal changes to the second amplitude by first amplitude, passing through the interval
After time, the AC signal output is controlled.
2. the method that control AC signal is exported as claimed in claim 1, it is characterised in that the pulse signal is by the first width
At the time of value changes are at the time of the second amplitude for square-wave signal trailing edge correspondence.
3. the method that control AC signal is exported as claimed in claim 1, it is characterised in that calculate the exchange letter described
Number phase angle changed to by the first phase angle value before the interval time of the preset phase angle value, in addition to：
The cycle of the square-wave signal is calculated, the cycle of the square-wave signal is the cycle of the AC signal.
4. the method that control AC signal is exported as claimed in claim 1, it is characterised in that also include：
Show the preset phase angle value.
5. a kind of device for controlling AC signal to export, it is characterised in that including：Acquisition module, receiving module, processing calculate mould
Block and output control module, wherein：
The acquisition module, for obtaining pulse signal, the cycle of the pulse signal and the cycle phase of the AC signal are same,
First phase angle value at the time of the pulse signal changes to the second amplitude by first amplitude with the AC signal is corresponding；
The receiving module, for receiving preset phase angle value；
The processing computing module, for the cycle according to the first phase angle value and the AC signal, calculates described hand over
The phase angle of stream signal is changed to the interval time of the preset phase angle value by the first phase angle value；
The control output module, for opening from detecting at the time of the pulse signal changes to the second amplitude by first amplitude
Beginning timing, after the interval time, is controlling the AC signal output；
Wherein, the acquisition module includes：
The AC signal is converted to the connection of component in the waveform changing circuit of square-wave signal, the waveform changing circuit
Relation includes：
Resistance R1, resistance R2 connect with resistance R3, and diode D1 is in parallel after being connected with light emitting diode with resistance R2, and described two
Pole pipe D1 negative electrode is connected with the anode of the light emitting diode, and the light emitting diode constitutes isolation circuit with phototriode
U1, the colelctor electrode of the phototriode is connected with power supply, and emitter stage is grounded after being connected with resistance R4 and resistance R5, triode Q1
Base stage be connected to the resistance R4 and resistance R5 centre, the colelctor electrode of the triode Q1 connected with resistance R6 after with
Power supply is connected, the grounded emitter of the triode Q1.
6. the device that control AC signal is exported as claimed in claim 5, it is characterised in that the control output module is used for
Timing includes since detecting at the time of the pulse signal changes to the second amplitude by first amplitude：
Since the control output module specifically for the timing detecting at the time of the square-wave signal trailing edge is corresponded to.
7. the device that control AC signal is exported as claimed in claim 5, it is characterised in that also include：
Display module, for showing the preset phase angle value.
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| CN201410453882.7A CN104198781B (en) | 2014-09-05 | 2014-09-05 | A kind of method and device for controlling AC signal to export |
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| CN201410453882.7A CN104198781B (en) | 2014-09-05 | 2014-09-05 | A kind of method and device for controlling AC signal to export |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103488220A (en) * | 2013-09-28 | 2014-01-01 | 迈普通信技术股份有限公司 | Power supply device and power supply method |
| CN103701436A (en) * | 2012-09-27 | 2014-04-02 | 浙江大华技术股份有限公司 | External synchronous trigger signal generating method and equipment |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5752321A (en) * | 1980-09-10 | 1982-03-27 | Mitsubishi Electric Corp | Phase discriminator |
| EP1912398B1 (en) * | 2006-02-03 | 2014-11-12 | Anritsu Corporation | Phase control device |
| US8102683B2 (en) * | 2010-02-09 | 2012-01-24 | Power Integrations, Inc. | Phase angle measurement of a dimming circuit for a switching power supply |
| CN102548122B (en) * | 2010-10-24 | 2015-09-02 | 理察·蓝德立·葛瑞 | Configuration setup control device and control method thereof |
| CN103825587B (en) * | 2014-03-19 | 2017-05-24 | 成都引众数字设备有限公司 | Circuit for extracting square wave signal corresponding to high-amplitude sine wave |
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Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103701436A (en) * | 2012-09-27 | 2014-04-02 | 浙江大华技术股份有限公司 | External synchronous trigger signal generating method and equipment |
| CN103488220A (en) * | 2013-09-28 | 2014-01-01 | 迈普通信技术股份有限公司 | Power supply device and power supply method |
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