CN105024614A - Method for sampling current of motor stator - Google Patents
Method for sampling current of motor stator Download PDFInfo
- Publication number
- CN105024614A CN105024614A CN201510385986.3A CN201510385986A CN105024614A CN 105024614 A CN105024614 A CN 105024614A CN 201510385986 A CN201510385986 A CN 201510385986A CN 105024614 A CN105024614 A CN 105024614A
- Authority
- CN
- China
- Prior art keywords
- phase
- sampling
- current
- motor
- electric current
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 36
- 238000005070 sampling Methods 0.000 title claims abstract description 27
- 230000003068 static effect Effects 0.000 claims abstract description 12
- 230000008859 change Effects 0.000 claims description 7
- 239000013598 vector Substances 0.000 abstract description 11
- 230000008569 process Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 4
- 230000007935 neutral effect Effects 0.000 description 4
- 230000003321 amplification Effects 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 230000003750 conditioning effect Effects 0.000 description 3
- 238000003199 nucleic acid amplification method Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 238000002405 diagnostic procedure Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000008447 perception Effects 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000010183 spectrum analysis Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
Landscapes
- Control Of Ac Motors In General (AREA)
Abstract
The invention discloses a method for sampling a current of a motor stator in motor vector control, and the method comprises the steps: firstly defining the switching states of an inverter bridge arm as Sa, Sb, and Sc, wherein the switching state is '1' when the bridge arm is connected, or else the switching state is '1'; secondly carrying out the collection of two-phase stator currents when upper bridge arms are completely switched off and the lower bridge arms are completely switched on; carrying out the changing of the collected two-phase stator currents from a static three-phase coordinates to a static two-phase orthogonal coordinate system through a constraint condition (ia+ib+ic=0), thereby achieving the accurate collection of the stator currents, wherein ia, ib and ic are the stator currents of A, B and C phases of a motor. According to the invention, a specific sampling method is employed, and the method can reduce the complexity of collection. The method can obtain the stator currents of A and B phases at a time, and can save cost.
Description
Technical field
The invention belongs to the technical field of motor vector control, particularly stator current detects and the method for sampling.
Background technology
The correct sampling of stator current is the basis realizing motor vector control.In the middle of vector control, the indices of the direct influential system of capability of fast response of current inner loop, it is very crucial that coordinate transform is carried out in correct stator current collection.
Such as patent application 201410474695.7, disclose a kind of double-fed aerogenerator stator current diagnostic method of impeller imbalance fault, the method specifically comprises: gather doubly-fed generation machine stator monophase current, utilize fft analysis to extract the fundamental frequency of this stator monophase current; The fault signature component of stator phase currents under the fundamental frequency calculating impeller imbalance fault that utilization obtains; Gather impeller of wind turbine set tach signal, calculate stator current impeller imbalance fault characteristic frequency; The fault signature component of FFT to the stator phase currents obtained is utilized to carry out spectrum analysis, according to fault characteristic frequency now, extract the amplitude at this frequency place, and during with same wind speed operating mode, Wind turbines characteristic frequency amplitude is under normal circumstances made comparisons the failure judgement order of severity.The method utilize frequency characteristic to carry out breakdown judge, sampling and calculate all rather complicated, and frequency easily receives many factors interference, is difficult to the accurate sampling done.
Therefore, in the middle of motor stator current control system, conventional current sample mainly contains: the two-phase phase current 1) utilizing two current sensor device sample motor; 2) utilize the electric current of single resistance sampling DC bus, reconstruct the phase current of motor with this.
Utilize that the cost of current sensor method is higher, volume is comparatively large, be often restricted at the more sensitive electric machine speed regulation product of cost ratio.At single resistance sampling, in order to gather bus current and phase current reconstruction, adopt space voltage vector modulation method.In practice, the delayed meeting of part of hardware causes single resistance sampling can not carry out electric current reconstructing in non-viewing district, and the double sampling in a sector also can increase complexity in control, as depicted in figs. 1 and 2, in the first sector, double sampling process switch conduction situation and electric current flow to situation.
Summary of the invention
For solving the problem, the object of the present invention is to provide a kind of method of sampling of motor stator electric current, the method both can reduce the complexity of collection, again can be cost-saving.
For achieving the above object, technical scheme of the present invention is as follows.
A method of sampling for motor stator electric current, the method comprises:
101, the on off state defining inverter leg is S
a, S
b, S
c, when upper brachium pontis conducting, on off state is ' 1 ', otherwise state is ' 0 ';
102, upper brachium pontis is all in shutoff, the moment that lower brachium pontis is all opened, i.e. S
as
bs
c=' 000 ', carry out collection two-phase stator current;
103, the two-phase stator current collected, utilizes i
a+ i
b+ i
c=0 this constraints, then carry out the change of static three phase coordinates to the static orthogonal coordinate system of two-phase, wherein, i
a, i
band i
cit is the stator current of motor A phase, B phase and C phase.
In described step 102, the resistance of sample circuit is precision resistance R
1and R
2, be arranged between lower brachium pontis and ground, and A and B is amplifier, be used as conditioning stator current, DC bus side is voltage is V
dc, GND is ground.
In the first sector, A phase stator current is through precision resistance, through diode continuousing flow, flow to the neutral point in the middle of motor again, for B phase stator current, flow out from the neutral point of electric current and flow to the negative terminal of power supply after precision resistance again, as long as gather the stator current that once just can draw A and B phase like this, the acquisition mode of sector is also similar in addition.
In described method, can not conducting simultaneously between any time upper and lower bridge arm, otherwise power supply is straight-through then can damage inverter.
Described static three phase coordinates to the expression formula of the change of the static orthogonal coordinate system of two-phase are:
Be connected to lifting circuit after described sample circuit, because the stator current collecting motor is bipolarity, and the signal of ramp metering device is unipolarity and be between 0V-3.3V, needs one to promote circuit.
Further, described lifting circuit has amplifying circuit simultaneously, and when motor is in zero load or load is less, the value of stator current is less, needs to amplify, and the multiple of amplification is unsuitable excessive, and the peak value of the voltage signal after amplification is preferably between 0V-3.3V.
The present invention, by the specific method of sampling, can reduce the complexity of collection, as long as gather the stator current that once just can draw A and B phase, and again can be cost-saving.
Accompanying drawing explanation
Fig. 1 is the design frame chart of single resistance sampling mode one.
Fig. 2 is the design frame chart of single resistance sampling mode two.
Fig. 3 is space voltage vector and sector division figure.
Fig. 4 is that the invention process stator current gathers block diagram.
Fig. 5 is the current direction figure of sampling instant.
Fig. 6 is the circuit diagram that the invention process promotes circuit.
Fig. 7 is the circuit diagram of the invention process amplifying circuit.
Fig. 8 is the process schematic of the invention process stator current modulation.
Embodiment
In order to make object of the present invention, technical scheme and advantage clearly understand, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, be not intended to limit the present invention.
Please refer to shown in Fig. 4, the method for sampling of the motor stator electric current that the present invention realizes, the method comprises:
101, the on off state defining inverter leg is S
a, S
b, S
c, when upper brachium pontis conducting, on off state is ' 1 ', otherwise state is ' 0 '; Here adopt the mode of SVPWM equally, the principle of which is: by controlling non-zero voltage basic voltage vectors U
0(100), U
60(110), U
120(010), U
180(011), U
240(011), U
300and zero vector 0 (101)
000(000), 0
111(000) action time, the control to alternating current machine voltage waveform is realized.Space voltage vector plane is divided into 6 sectors by the voltage vector of 6 non-zeros, as shown in Figure 3.Motor is M, and resistance is precision resistance R
1and R
2, be arranged between lower brachium pontis and ground, and A and B is amplifier, be used as conditioning stator current, DC bus side is voltage is V
dc, GND is ground.
102, when brachium pontis on inverter is all in shutoff, the moment that lower brachium pontis is all opened carries out collection two-phase stator current; In any one sector, only 0
000(000) this moment gathers, and as shown in Figure 4, because the coil of motor winding is in perception, the phase current flow through on coil can not suddenly change, and now flows through precision resistance R
1and R
2electric current be the electric current of stator afterflow, the diode in parallel with lower brachium pontis can play the effect of afterflow, is the stator current of motor.
Shown in composition graphs 5, gather in the first sector, A phase stator current through precision resistance, through diode continuousing flow, flow to the neutral point in the middle of motor again, for B phase, flow out from the neutral point of electric current and flow again after precision resistance to the negative terminal of power supply, in different sectors, the current direction of A and B phase as shown in Figure 5, as long as gather the stator current that once just can draw A and B phase in any one sector, in other sector, current direction as shown in Figure 5.
103, the two-phase stator current collected, utilizes i
a+ i
b+ i
c=0 this constraints, then carry out the change of static three phase coordinates to the static orthogonal coordinate system of two-phase, wherein, i
a, i
band i
cit is the stator current of motor A phase, B phase and C phase.
Expression formula is now:
For the P75NF75 that the above-mentioned inverter mentioned can be ST (STMicw Electronics) company, precision resistance can be 0.5 Ω, and power is 1W, 1% precision, and encapsulated type is 2512.Integrated transporting discharging chip can be LM358.For motor, it can be permagnetic synchronous motor, four pairs of poles, rated power is 30W, controller can be the EP3C25Q240C8N of the Cyclone type III that altera corp provides, here AD conversion chip can be AD9201, and the square wave rising edge that this chip is exported by FPGA and trailing edge trigger, and can change two-way stator current simultaneously.
PWM is modulated in the middle of fpga chip internal procedure, the carrier wave used is triangular wave, here adopt Voltage space vector PWM (SVPWM) control technology, modulating wave is saddle ripple, triangular wave start counting, be exactly now gather the moment, at this moment on inverter, brachium pontis turns off, and lower brachium pontis is opened, and control synchronization exports a pulse signal on FPGA, thus trigger peripheral A/D chip, make it start conversion.
The stator current collecting motor is bipolarity, and the signal of ramp metering device is unipolarity and be between 0V-3.3V, needs one to promote circuit, as shown in Figure 6.In addition, motor be in zero load or load less when, the value of stator current is less, needs to amplify, and as shown in Figure 7, the multiple of amplification is unsuitable excessive, and its peak value is between 0-3.3V for amplifying circuit.
Above-mentioned circuit 6 is known:
generally speaking, R is had
1=R
2, now V
ref=1.65V.
The amplifying circuit of stator current A phase as shown in Figure 7, by the V of above-mentioned output
refvoltage be connected to R in the middle of figure
8, work as R
3=R
6, R
4=R
7, R
5=R
8time, the multiplication factor obtained is:
obtain a suitable correct multiplication factor to need constantly to adjust R
3, R
4and R
5value.When pulse exports triggering signal from FPGA, AD9201 carries out analog-to-digital conversion after receiving the pulse signal from FPGA, directly delivers to follow-up coordinate transform computing after the correct digital quantity obtained.
Equally, the conditioning for the stator current of B phase is also analyzed based on above.
Figure 8 shows that the stator current that motor reads is after ovennodulation, is finally sent to the schematic diagram of controller, inside controller what obtain is all digital quantity, the is-symbol position of 0 of its highest order and 1 representative, 1 represents negative, and 0 is just representing.
The present invention, by the above-mentioned method of sampling, can reduce the complexity of collection, as long as gather the stator current that once just can draw A and B phase, and again can be cost-saving.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, all any amendments done within the spirit and principles in the present invention, equivalent replacement and improvement etc., all should be included within protection scope of the present invention.
Claims (6)
1. a method of sampling for motor stator electric current, is characterized in that the method comprises:
101, the on off state defining inverter leg is S
a, S
b, S
c, when upper brachium pontis conducting, on off state is ' 1 ', otherwise state is ' 0 ';
102, when brachium pontis on inverter is all in shutoff, the moment that lower brachium pontis is all opened, i.e. S
as
bs
c=' 000 ', carry out collection two-phase stator current;
103, the two-phase stator current collected, utilizes i
a+ i
b+ i
c=0 this constraints, then carry out the change of static three phase coordinates to the static orthogonal coordinate system of two-phase, wherein, i
a, i
band i
cit is the stator current of motor A phase, B phase and C phase.
2. the method for sampling of motor stator electric current as claimed in claim 1, it is characterized in that in described step 102, the resistance of sample circuit is precision resistance R
1and R
2, be arranged between lower brachium pontis and ground, DC bus side is voltage is V
dc, GND is ground.
3. the method for sampling of motor stator electric current as claimed in claim 1, is characterized in that in described method, can not conducting simultaneously between any time upper and lower bridge arm.
4. the method for sampling of motor stator electric current as claimed in claim 1, is characterized in that described static three phase coordinates to the expression formula of the change of the static orthogonal coordinate system of two-phase are:
5. the method for sampling of motor stator electric current as claimed in claim 2, is connected to lifting circuit after it is characterized in that described sample circuit.
6. the method for sampling of motor stator electric current as claimed in claim 2, it is characterized in that described after be connected to amplifying circuit, and the peak value of voltage signal after amplifying is between 0V-3.3V.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510385986.3A CN105024614A (en) | 2015-06-30 | 2015-06-30 | Method for sampling current of motor stator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510385986.3A CN105024614A (en) | 2015-06-30 | 2015-06-30 | Method for sampling current of motor stator |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN105024614A true CN105024614A (en) | 2015-11-04 |
Family
ID=54414377
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510385986.3A Pending CN105024614A (en) | 2015-06-30 | 2015-06-30 | Method for sampling current of motor stator |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN105024614A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109729757A (en) * | 2016-08-08 | 2019-05-07 | 爱信精机株式会社 | Controller for motor |
| CN111412114A (en) * | 2019-12-26 | 2020-07-14 | 浙江运达风电股份有限公司 | A Wind Turbine Impeller Unbalance Detection Method Based on Stator Current Envelope Spectrum |
| CN112051535A (en) * | 2020-09-28 | 2020-12-08 | 珠海格力电器股份有限公司 | Signal determination device, storage medium, and electronic device |
| CN112087171A (en) * | 2020-08-26 | 2020-12-15 | 湖南英迈智能科技有限公司 | Current smoothing method and device |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4772996A (en) * | 1986-04-11 | 1988-09-20 | Hitachi, Ltd. | Load current detecting device for pulse width modulation inverter |
| JP2008253008A (en) * | 2007-03-29 | 2008-10-16 | Mitsubishi Electric Corp | Power converter and method for deciding incorrect connection of power supply |
| CN101567654A (en) * | 2008-04-25 | 2009-10-28 | 上海鲍麦克斯电子科技有限公司 | Motor control method using space vector pulse width modulation and controller thereof |
| CN100568699C (en) * | 2004-07-20 | 2009-12-09 | 松下电器产业株式会社 | Converter device |
| JP2014011944A (en) * | 2012-07-03 | 2014-01-20 | Mitsubishi Electric Corp | Power conversion system and power conversion method |
| CN105765851A (en) * | 2013-12-03 | 2016-07-13 | 三菱电机株式会社 | Power conversion devices, motor drives equipped with them, blowers and compressors equipped with them, and air conditioners, refrigerators, and refrigerating machines equipped with them |
-
2015
- 2015-06-30 CN CN201510385986.3A patent/CN105024614A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4772996A (en) * | 1986-04-11 | 1988-09-20 | Hitachi, Ltd. | Load current detecting device for pulse width modulation inverter |
| CN100568699C (en) * | 2004-07-20 | 2009-12-09 | 松下电器产业株式会社 | Converter device |
| JP2008253008A (en) * | 2007-03-29 | 2008-10-16 | Mitsubishi Electric Corp | Power converter and method for deciding incorrect connection of power supply |
| CN101567654A (en) * | 2008-04-25 | 2009-10-28 | 上海鲍麦克斯电子科技有限公司 | Motor control method using space vector pulse width modulation and controller thereof |
| JP2014011944A (en) * | 2012-07-03 | 2014-01-20 | Mitsubishi Electric Corp | Power conversion system and power conversion method |
| CN105765851A (en) * | 2013-12-03 | 2016-07-13 | 三菱电机株式会社 | Power conversion devices, motor drives equipped with them, blowers and compressors equipped with them, and air conditioners, refrigerators, and refrigerating machines equipped with them |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109729757A (en) * | 2016-08-08 | 2019-05-07 | 爱信精机株式会社 | Controller for motor |
| CN111412114A (en) * | 2019-12-26 | 2020-07-14 | 浙江运达风电股份有限公司 | A Wind Turbine Impeller Unbalance Detection Method Based on Stator Current Envelope Spectrum |
| CN111412114B (en) * | 2019-12-26 | 2021-12-07 | 浙江运达风电股份有限公司 | Wind turbine generator impeller imbalance detection method based on stator current envelope spectrum |
| CN112087171A (en) * | 2020-08-26 | 2020-12-15 | 湖南英迈智能科技有限公司 | Current smoothing method and device |
| CN112087171B (en) * | 2020-08-26 | 2022-02-11 | 湖南英迈智能科技有限公司 | Current smoothing method and device |
| CN112051535A (en) * | 2020-09-28 | 2020-12-08 | 珠海格力电器股份有限公司 | Signal determination device, storage medium, and electronic device |
| CN112051535B (en) * | 2020-09-28 | 2021-10-22 | 珠海格力电器股份有限公司 | Signal determination method and device, storage medium and electronic device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN105576991B (en) | Turnable pulse width modulator approach | |
| Higuchi et al. | An improvement of performance for small-scaled wind power generating system with permanent magnet type synchronous generator | |
| CN103683319B (en) | Based on the control method of grid-connected inverter that stagnant ring is modulated during unbalanced source voltage | |
| Parida et al. | An improved control scheme for grid connected doubly fed induction generator considering wind-solar hybrid system | |
| CN104600748B (en) | A kind of isolated island micro-capacitance sensor multi-inverter control system possessing active power filtering function and method of work thereof | |
| CN102035216B (en) | Grid-connected control method and device for combining generator and matrix converter | |
| CN105024614A (en) | Method for sampling current of motor stator | |
| Buticchi et al. | Active rectifier with integrated system control for microwind power systems | |
| CN105119536A (en) | Low-cost motor drive topology and control method thereof | |
| CN105305483B (en) | Impedance model optimization method for inverter grid-connected power source measurement under external disturbance signal | |
| CN104734537B (en) | A kind of wind-powered electricity generation converter Control method being controlled based on positive-negative sequence current internal ring | |
| CN104022665A (en) | Bridge arm instantaneous current direct control method of modular multilevel converter | |
| CN201975800U (en) | Half-controlled converter drives AC permanent magnet synchronous generator system | |
| CN101895128A (en) | Control method of voltage fluctuation feedback of grid-connected current transformer under asymmetric voltage | |
| CN103633913B (en) | The double-fed blower fan low voltage traversing control method followed the tracks of based on counter current and system | |
| KR102724468B1 (en) | SYSTEM PHASE DETECTING METHOD and GRID CONNECTED CONVERTER | |
| CN208539775U (en) | Current detection circuit and frequency converter for inverter | |
| CN114157167A (en) | Two-level driving device based on real-time simulation controller | |
| CN105958525A (en) | PWM gird connected inverter control method of permanent magnetism wind generator system | |
| Obeidat et al. | Simulation of grid connected HVDC offshore wind farm topolgies | |
| Sharma et al. | An autonomous wind energy conversion system with permanent magnet synchronous generator | |
| CN105024396A (en) | Energy feedback frequency converter | |
| CN103944185A (en) | Double-fed asynchronous motor low-voltage ride through control system and method | |
| CN212486397U (en) | Two-level driving device based on real-time simulation controller | |
| CN103630771A (en) | Total power testing platform for frequency converter for use in wind power generation |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20151104 |
|
| RJ01 | Rejection of invention patent application after publication |