CN106998203A - A kind of phase-lock technique and device - Google Patents
A kind of phase-lock technique and device Download PDFInfo
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- CN106998203A CN106998203A CN201610045684.6A CN201610045684A CN106998203A CN 106998203 A CN106998203 A CN 106998203A CN 201610045684 A CN201610045684 A CN 201610045684A CN 106998203 A CN106998203 A CN 106998203A
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- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
- H03L7/00—Automatic control of frequency or phase; Synchronisation
- H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
- H03L7/08—Details of the phase-locked loop
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- 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
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
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- Stabilization Of Oscillater, Synchronisation, Frequency Synthesizers (AREA)
Abstract
The invention provides a kind of phase-lock technique and device, wherein, methods described includes：Phase-locking device carries out voltage division processing to the line voltage of input, and square-wave signal is generated according to the line voltage after the partial pressure；According to the square-wave signal, the first frequency of the line voltage of the input is determined；The line voltage of the input is sampled, to the voltage progress first integral processing sampled and obtained, the first result is obtained；Park transforms are carried out to first result, second processing result is obtained；The second frequency of the line voltage is calculated according to the second processing result and the first frequency；Voltage-phase is calculated according to the second frequency and first frequency.When the line voltage that the present invention solves input is influenceed by factors such as harmonic waves, it is impossible to the problem of ensureing higher lock phase precision, the technique effect for the stability for ensureing lock phase precision is achieved.
Description
Technical field
The present invention relates to Phase Lock Technique field, in particular to a kind of phase-lock technique and device.
Background technology
Phaselocked loop section in single-phase electric system is that the quality of single-phase inverter, the basis of Power Quality Detection, therefore phase locking unit performance is directly connected to the performance of the said equipment.Lock is mutually a kind of technology for making to be controlled by standard signal or extraneous signal by the phase of controlled oscillator, and it is used for realizing the frequency or phase with extraneous signal Phase synchronization, or tracking extraneous signal.
At present, phase-lock technique generally uses digital closed loop Phase Lock Technique, and method mainly has：Phase Lock Technique based on zero passage detection, based on the Phase Lock Technique of multiplication phase demodulation, based on Fast Fourier Transform (FFT) (DFT) Phase Lock Technique, and Phase Lock Technique based on synchronous rotating angle etc..The operation such as rotating coordinate transformation generally can be further carried out using Hilbert (Hilbert) conversion or Parker (park) inverse transformation generation vertical signal.The structure of different Phase Lock Techniques is generally substantially similar, and Main Differences are the acquisition differed.
But, lock phase precision often relies on the accuracy of detection to the line voltage frequency of input, and when the line voltage of input is influenceed by factors such as harmonic waves, the frequency accuracy of the line voltage detected may be not accurate enough, then cannot ensure higher lock phase precision.
For how to solve the problem of existing lock phase precision is unstable, effective settling mode is not yet proposed at present.
The content of the invention
The embodiments of the invention provide a kind of phase-lock technique and device, to ensure the stability for locking phase precision.
In one embodiment, a kind of phase-lock technique, including：
Phase-locking device carries out voltage division processing to the line voltage of input, and square-wave signal is generated according to the line voltage after the partial pressure；
According to the square-wave signal, the first frequency of the line voltage of the input is determined；
The line voltage of the input is sampled, to the voltage progress first integral processing sampled and obtained, the first result is obtained；
Park transforms are carried out to first result, second processing result is obtained；
The second frequency of the line voltage is calculated according to the second processing result and the first frequency；
Voltage-phase is calculated according to the second frequency and first frequency.
In one embodiment, the line voltage according to after partial pressure generates square-wave signal, is realized using zero-crossing comparator or hysteresis loop comparator.
In one embodiment, described pair of obtained voltage of sampling, which carries out first integral processing, includes：Second order improper integral processing is carried out to the voltage that sampling is obtained.
In one embodiment, first result includes：Two orthogonal AC signals.
In one embodiment, the second processing result is two direct current signals；The value of one of direct current signal is 0.
In one embodiment, the second frequency that the line voltage is calculated according to second processing result and first frequency, is specifically included：According to the first frequency, carry out proportional plus integral control to the second processing result, signal of the generation with second frequency, using the second frequency as line voltage actual frequency.
In one embodiment, before the second frequency is calculated, methods described also includes：According to the second processing result, the amplitude and virtual value of the line voltage are calculated.
In one embodiment, before the second frequency is calculated, methods described also includes：Judge whether the amplitude and virtual value meet grid-connected requirement；If judged result is meets, the second frequency of the line voltage is calculated according to the second processing result and the first frequency.
In one embodiment, before the voltage-phase is calculated, methods described also includes：Judge whether the second line voltage frequency meets grid-connected requirement；If judged result is meets, voltage-phase is calculated according to the second frequency and first frequency.
In one embodiment, a kind of phase-locking device, including：Square-wave signal generation module, first frequency determining module, sampling filter processing module, park transforms processing module, second frequency computing module and voltage-phase computing module；Wherein,
The square-wave signal generation module, carries out voltage division processing for the line voltage to input, square-wave signal is generated according to the line voltage after the partial pressure；
The first frequency determining module, for the square-wave signal generated according to the square-wave signal generation module, determines the first frequency of the line voltage of the input；
The sampling filter processing module, samples for the line voltage to the input, to the voltage progress first integral processing sampled and obtained, obtains the first result；The first integral processing includes：The processing of second order improper integral；
The park transforms processing module, the first result for being obtained to the sampling filter processing module carries out park transforms, obtains second processing result；
The second frequency computing module, for the second processing result and the first frequency determining module obtained according to the park transforms processing module, obtained first frequency calculates the second frequency of the line voltage；
The voltage-phase computing module, the first frequency obtained for the second frequency obtained according to the second frequency computing module and the first frequency determining module calculates voltage-phase.
In one embodiment, the phase-locking device also includes：Amplitude computing module, for the second processing result obtained according to the park transforms processing module, calculates the amplitude and virtual value of the line voltage.
In one embodiment, the phase-locking device also includes：First judge module, for judging whether amplitude that the amplitude computing module obtains and virtual value meet grid-connected requirement.
In one embodiment, the phase-locking device also includes：Second judge module, for judging whether the second line voltage frequency that the second frequency computing module is obtained meets grid-connected requirement.
In the above-described embodiments, employ second order improper integral to handle obtained voltage of sampling, obtaining the colleague of quadrature component, can also realize and the line voltage is filtered, it is ensured that the stability of lock phase precision.Even if power grid environment is severe, when line voltage receives the influence of the factors such as harmonic wave, the phase-lock technique and device provided using the embodiment of the present application still can ensure to lock phase precision.On the other hand, the embodiment of the present application is provided phase-lock technique and device, with filter effect, it is not necessary to the extra filtering for carrying out hardware, can reduce the difficulty of hardware design, the cost of hardware facility be saved, at the same time it can also the delay for avoiding hardware filtering from causing.
Brief description of the drawings
The accompanying drawing for constituting the part of the application is used for providing a further understanding of the present invention, and schematic description and description of the invention is used to explain the present invention, does not constitute inappropriate limitation of the present invention.In the accompanying drawings：
Fig. 1 is the flow chart of phase-lock technique according to embodiments of the present invention；
Fig. 2 is the module map of phase-locking device according to embodiments of the present invention.
Embodiment
For the object, technical solutions and advantages of the present invention are more clearly understood, with reference to embodiment and accompanying drawing, the present invention is described in further details.Here, the exemplary embodiment of the present invention and its illustrate to be used to explain the present invention, it is but not as a limitation of the invention.
Fig. 1 is the flow chart of phase-lock technique according to embodiments of the present invention.As shown in figure 1, the phase-lock technique can include：
S101：Phase-locking device carries out voltage division processing to the line voltage of input, and square-wave signal is generated according to the line voltage after the partial pressure.
The line voltage according to after partial pressure generates square-wave signal, it is possible to use zero-crossing comparator or hysteresis loop comparator are realized.
S102：According to the square-wave signal, the first frequency of the line voltage of the input is determined.
The first frequency of the line voltage that the input is determined according to square-wave signal can be realized using control chip DSP.Specifically, the square-wave signal can be inputted to the ECAP pins of the dsp chip, ECAP modules can measure the frequency of square-wave signal in real time.The frequency of such as described line voltage can be 50 hertz (HZ) or 60HZ, then the number of times of ECAP module renewal frequencies can be 50 times per second or per second 60 times.
S103：The line voltage of the input is sampled, to the voltage progress first integral processing sampled and obtained, the first result is obtained.
The line voltage of the input can be sampled, during sampling, sample frequency can be set as arbitrary value.Generally, the value of the sample frequency is higher, and response speed is faster.
The first integral processing can include：The processing of second order improper integral.Handled by the second order improper integral, quadrature component can be produced, the filter effect to the line voltage can also be realized.It can ensure that lock phase precision is not influenceed by factors such as Voltage Harmonics.
Therefore, first result can be two orthogonal AC signals.
S104：Park transforms are carried out to first result, second processing result is obtained.
Parker (park) can be carried out to first result to change, can obtain second processing result.The second processing result can be two direct current signals.Wherein, the value for having a direct current signal can be 0.
S105：The second frequency of the line voltage is calculated according to the second processing result and first frequency.
In another embodiment, before the second frequency is calculated, methods described can also include：According to the second processing result, the amplitude and virtual value of the line voltage are calculated.
Further, before the second frequency is calculated, methods described can also include：Judge whether the amplitude and virtual value meet grid-connected requirement, if judged result can perform step S105 to meet.Further, if judged result can switch to combining inverter off-network state to be unsatisfactory for.
The second frequency that the line voltage is calculated according to second processing result and first frequency, can specifically include：According to the first frequency, can to the second processing result carry out PI controls (proportional plus integral control), generation with second frequency signal, using the second frequency as line voltage actual frequency.
S106：Voltage-phase is calculated according to the second frequency and first frequency.
In another way of example, before the voltage-phase is calculated, methods described can also include：Judge whether the second line voltage frequency meets grid-connected requirement.If judged result can perform step S106 to meet.Further, if judged result can be converted to combining inverter off-network state to be unsatisfactory for.
As can be seen from the above description, the embodiment of the present invention realizes following technique effect：Employ second order improper integral to handle obtained voltage of sampling, obtaining the colleague of quadrature component, can also realize and the line voltage is filtered, it is ensured that the stability of lock phase precision.Even if power grid environment is severe, when line voltage receives the influence of the factors such as harmonic wave, the phase-lock technique provided using the embodiment of the present application still can ensure to lock phase precision.On the other hand, the phase-lock technique that the embodiment of the present application is provided, with filter effect, it is not necessary to the extra filtering for carrying out hardware, can reduce the difficulty of hardware design, the cost of hardware facility be saved, at the same time it can also the delay for avoiding hardware filtering from causing.
Based on same inventive concept, a kind of phase-locking device is additionally provided in the embodiment of the present invention, as described in the following examples.Because the principle that phase-locking device solves problem is similar to phase-lock technique, therefore implementations of phase-locking device may refer to the implementation of phase-lock technique, repeatedly in place of repeat no more.Used below, term " unit " or " module " can realize the combination of the software and/or hardware of predetermined function.Although the device described by following examples is preferably realized with software, hardware, or the realization of the combination of software and hardware is also that may and be contemplated.Fig. 2 is a kind of module map of the phase-locking device of the embodiment of the present invention, as shown in Fig. 2 the phase-locking device can include：Square-wave signal generation module 201, first frequency determining module 202, sampling filter processing module 203, park transforms processing module 204, second frequency computing module 205 and voltage-phase computing module 206.
The square-wave signal generation module 201, can be used for carrying out voltage division processing to the line voltage of input, square-wave signal is generated according to the line voltage after the partial pressure.The square-wave signal generation module 201 can be zero-crossing comparator or hysteresis loop comparator.
The first frequency determining module 202, can be used for the square-wave signal generated according to the square-wave signal generation module 201, determines the first frequency of the line voltage of the input.
The sampling filter processing module 203, can be used for sampling to the line voltage of the input, to the voltage progress first integral processing sampled and obtained, obtain the first result.The first integral processing can include：The processing of second order improper integral.First result can be two orthogonal AC signals.
The park transforms processing module 204, the first result that can be used for obtaining the sampling filter processing module 203 carries out park transforms, obtains second processing result.The second processing result is two direct current signals；The value of one of direct current signal is 0.
The second frequency computing module 205, can be used for the second frequency of the first frequency that second processing result and the first frequency determining module 202 the are obtained calculating line voltage obtained according to the park transforms processing module 204.
The voltage-phase computing module 206, can be used for the first frequency that the second frequency that is obtained according to the second frequency computing module 205 and the first frequency determining module 202 obtain and calculates voltage-phase.
In another embodiment, the phase-locking device can also include：Amplitude computing module, can be used for the second processing result obtained according to the park transforms processing module 204, calculate the amplitude and virtual value of the line voltage.
In another embodiment, the phase-locking device can also include：First judge module, can be used for judging whether amplitude that the amplitude computing module is obtained and virtual value meet grid-connected requirement.
In another embodiment, the phase-locking device can also include：Second judge module, can be used for judging whether the second line voltage frequency that the second frequency computing module 205 is obtained meets grid-connected requirement.
Obviously, those skilled in the art should be understood that, each module or each step of the above-mentioned embodiment of the present invention can be realized with general computing device, they can be concentrated on single computing device, or be distributed on the network that multiple computing devices are constituted, alternatively, they can be realized with the executable program code of computing device, so as to, it can be stored in storage device and be performed by computing device, and in some cases, can be with the step shown or described by being performed different from order herein, or they are fabricated to each integrated circuit modules respectively, or be fabricated to single integrated circuit module to realize by the multiple modules or step in them.So, the embodiment of the present invention is not restricted to any specific hardware and software combination.
The preferred embodiments of the present invention are the foregoing is only, are not intended to limit the invention, for those skilled in the art, the embodiment of the present invention there can be various modifications and variations.Within the spirit and principles of the invention, any modification, equivalent substitution and improvements made etc., should be included in the scope of the protection.
Claims (13)
1. a kind of phase-lock technique, it is characterised in that including：
Phase-locking device carries out voltage division processing to the line voltage of input, according to the power network electricity after the partial pressure
Pressure generation square-wave signal；
According to the square-wave signal, the first frequency of the line voltage of the input is determined；
The line voltage of the input is sampled, to the product of voltage progress first sampled and obtained
Office is managed, and obtains the first result；
Park transforms are carried out to first result, second processing result is obtained；
The second frequency of the line voltage is calculated according to the second processing result and the first frequency
Rate；
Voltage-phase is calculated according to the second frequency and first frequency.
2. a kind of phase-lock technique as claimed in claim 1, it is characterised in that described according to partial pressure
Line voltage generation square-wave signal afterwards, is realized using zero-crossing comparator or hysteresis loop comparator.
3. a kind of phase-lock technique as claimed in claim 1, it is characterised in that described pair is sampled
To voltage carry out first integral processing include：Second order Generalized Product office is carried out to the voltage that sampling is obtained
Reason.
4. a kind of phase-lock technique as claimed in claim 3, it is characterised in that first processing
As a result include：Two orthogonal AC signals.
5. a kind of phase-lock technique as claimed in claim 1, it is characterised in that the second processing
As a result it is two direct current signals；The value of one of direct current signal is 0.
6. a kind of phase-lock technique as claimed in claim 1, it is characterised in that described according to second
Result and first frequency calculate the second frequency of the line voltage, specifically include：According to described
First frequency, proportional plus integral control is carried out to the second processing result, and generation has second frequency
Signal, using the second frequency as line voltage actual frequency.
7. a kind of phase-lock technique as claimed in claim 1, it is characterised in that calculating described the
Before two frequencies, methods described also includes：According to the second processing result, the power network electricity is calculated
The amplitude and virtual value of pressure.
8. a kind of phase-lock technique as claimed in claim 7, it is characterised in that calculating described the
Before two frequencies, methods described also includes：Judge whether the amplitude and virtual value meet grid-connected requirement；
If judged result is meets, the power network is calculated according to the second processing result and the first frequency
The second frequency of voltage.
9. a kind of phase-lock technique as claimed in claim 1, it is characterised in that calculating the electricity
Press before phase, methods described also includes：Judge whether the second line voltage frequency meets grid-connected
It is required that；If judged result is meets, voltage-phase is calculated according to the second frequency and first frequency.
10. a kind of phase-locking device, it is characterised in that including：Square-wave signal generation module, the first frequency
Rate determining module, sampling filter processing module, park transforms processing module, second frequency computing module
With voltage-phase computing module；Wherein,
The square-wave signal generation module, voltage division processing is carried out for the line voltage to input, according to
Line voltage generation square-wave signal after the partial pressure；
The first frequency determining module, for the square wave generated according to the square-wave signal generation module
Signal, determines the first frequency of the line voltage of the input；
The sampling filter processing module, samples for the line voltage to the input, to institute
The voltage progress first integral processing that sampling is obtained is stated, the first result is obtained；The first integral
Processing includes：The processing of second order improper integral；
The park transforms processing module, for the sampling filter processing module is obtained first at
Manage result and carry out park transforms, obtain second processing result；
The second frequency computing module, for obtained according to the park transforms processing module second
Result and the first frequency determining module, obtained first frequency calculate the line voltage
Second frequency；
The voltage-phase computing module, for obtained according to the second frequency computing module second
The first frequency that frequency and the first frequency determining module are obtained calculates voltage-phase.
11. a kind of phase-locking device as claimed in claim 10, it is characterised in that also include：Width
It is worth computing module, for the second processing result obtained according to the park transforms processing module, calculates
The amplitude and virtual value of the line voltage.
12. a kind of phase-locking device as claimed in claim 11, it is characterised in that also include：The
One judge module, for judging whether amplitude that the amplitude computing module obtains and virtual value meet simultaneously
Net is required.
13. a kind of phase-locking device as claimed in claim 10, it is characterised in that also include：The
Two judge modules, for judging that the second line voltage frequency that the second frequency computing module is obtained is
It is no to meet grid-connected requirement.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109142857A (en) * | 2018-09-14 | 2019-01-04 | 中车青岛四方车辆研究所有限公司 | Energy balane system and method for the train with phase automatic calibration function |
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| CN103852640A (en) * | 2012-12-04 | 2014-06-11 | 中国北车股份有限公司 | Network voltage phase computing method and device and one-phase pulse width modulation rectifier |
| CN104836466A (en) * | 2015-05-28 | 2015-08-12 | 哈尔滨理工大学 | 60-degree coordinate system-based three-phase VIENNA rectifier and control method |
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- 2016-01-22 CN CN201610045684.6A patent/CN106998203A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103852640A (en) * | 2012-12-04 | 2014-06-11 | 中国北车股份有限公司 | Network voltage phase computing method and device and one-phase pulse width modulation rectifier |
| CN104836466A (en) * | 2015-05-28 | 2015-08-12 | 哈尔滨理工大学 | 60-degree coordinate system-based three-phase VIENNA rectifier and control method |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109142857A (en) * | 2018-09-14 | 2019-01-04 | 中车青岛四方车辆研究所有限公司 | Energy balane system and method for the train with phase automatic calibration function |
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Application publication date: 20170801 |