CN204269070U - A kind of change of revolving of measuring permanent-magnet synchronous motor rotor position angle encourages and decoder module - Google Patents
A kind of change of revolving of measuring permanent-magnet synchronous motor rotor position angle encourages and decoder module Download PDFInfo
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- CN204269070U CN204269070U CN201420742790.6U CN201420742790U CN204269070U CN 204269070 U CN204269070 U CN 204269070U CN 201420742790 U CN201420742790 U CN 201420742790U CN 204269070 U CN204269070 U CN 204269070U
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Abstract
The design of the utility model embodiment is a kind of becomes excitation and decoder module for measuring revolving of permanent-magnet synchronous motor rotor position angle, comprise signal exciting circuit, it is for being converted to the sine wave exciting signal that can drive rotary transformer by the digital square-wave from signal processor, comprise the multiple-stage filtering amplifying circuit for generating sine wave signal, and the push-pull circuit to be connected with the output terminal of described multi-stage filter circuit, for increasing the driving force of signal to drive the excitation winding of rotary transformer; And comprise signal decoding circuit, for decoding to the output signal of rotary transformer, comprising differential amplifier circuit, receiving the differential signal of described rotary transformer output and exporting the echoed signal after amplifying; Rectification reverse circuit, extracts the envelope of described echoed signal; And filtering circuit, the echoed signal after upset is filtered into straight level signal.The present embodiment can be effectively cost-saving, the effect only using some capacitance resistance wares and amplifier to reach decoding chip to play.
Description
Technical field
The utility model embodiment relates to Motor Control Field, in more specific words it, the utility model provides a kind of circuit module measuring permanent-magnet synchronous motor rotor position angle.
Background technology
Be embedded with the permagnetic synchronous motor of rotary transformer, the detection of its rotor-position is that the signal exported by gathering rotary transformer is determined, rotary transformer has high temperature resistant, moisture resistance, shock resistance, anti-interference and precision advantages of higher because of it, is widely used in automotive control system.Rotary transformer is an analog device, output be a kind of AC modulated signals, in digital control system, usually need the output signal of rotary transformer to convert digital angle signal to.The angle coding/decoding method of common rotary transformer has the method that adopts hardware decode chip to carry out decoding and the software decode method based on DSP.
Special R/D converter is had to realize analog/digital conversion at present and angle resolves function, the such as AU6802N1 of Japanese Duo Mo river company and the AD2SXX family chip of AD company of the U.S..The decoding performance of these special decoding chips is high, easy to use, can be demodulated to digitized absolute position signal fast, directly supplying revolving the modulated analog signal becoming output digitial controller and using.The precision of this kind of angle coding/decoding method is high, tracking velocity is fast, but due to the price comparison of hardware decode chip expensive, limit its application.
Along with significantly improving of the device arithmetic speeds such as DSP, the angle decoding based on software receives increasing concern.Angle coding/decoding method based on software mainly utilizes the chip that the data computing powers such as DSP, FPGA are stronger, by gathering the signal of rotary transformer, then obtains the position angle of rotor according to certain demodulating algorithm.Although this kind of method saves hardware decode chip, revolve the factors such as varying signal instability due to chip process such as FPGA, be restricted in the application of vehicle electric field.
Utility model content
Fundamental purpose of the present utility model is to provide a kind of circuit module for measuring permanent-magnet synchronous motor rotor position angle, the rotary transformer that this module is permagnetic synchronous motor provides pumping signal, and the output signal of rotary transformer is decoded, finally obtain rotor-position angle signal, thus solve expensive the caused problem that cannot use in a large number because of hardware decode chip.This module is primarily of the excitation circuit for generating of low cost and decoding circuit composition, the square wave being input to the fixed frequency of this module is transformed into sine wave exciting signal supply rotary transformer after the repeatedly filter and amplification of blasting circuit for generating, and the output signal of rotary transformer exports digitized absolute position signal after the processes such as differential amplify, upset, filtering.The utility model embodiment is well positioned to meet the requirement of vehicle electric field in decode precision, speed and stability.
Technical scheme: a kind of change of revolving of measuring permanent-magnet synchronous motor rotor position angle encourages and decoder module, comprise signal exciting circuit, it is for being converted to the sine wave exciting signal that can drive rotary transformer by the digital square-wave from signal processor, comprise: multiple-stage filtering amplifying circuit, for described digital signal being exported after repeatedly filter and amplification the sine wave signal of same frequency with it; And the push-pull circuit to be connected with the output terminal of described multi-stage filter circuit, for increasing the driving force of signal to drive the excitation winding of rotary transformer; And signal decoding circuit, for decoding to the output signal of rotary transformer, comprise differential amplifier circuit, receiving differential signal that described rotary transformer exports and exporting take 2.5V as sinusoidal echo and the cosine echoed signal of intermediate value; Rectification reverse circuit, for extracting the envelope of described sinusoidal echo and cosine echoed signal; Filtering circuit, is filtered into straight level signal by the echoed signal after upset.
In one embodiment, the digital square-wave that described signal exciting circuit sends for digital signal processor, only retains the sine wave of same frequency after amplifying after filtering.Use operational amplifier and capacitance resistance ware composition second-order filter amplifier, carry out filtering suppression for the higher hamonic wave except first-harmonic and times audio-frequency noise, suitably regulate enlargement factor to offset the decay of square-wave signal simultaneously, finally obtain required intermediate value and peak-to-peak value.
In one embodiment, described driver unit multiple-stage filtering amplifying circuit is mainly made up of three grades of filter amplification circuit, wherein said multiple-stage filtering amplifying circuit is configured to a part of higher hamonic wave by digital signal described in the filtering of first order filter amplification circuit, the intermediate value of waveform amplification and peak-to-peak value, sine wave output; By the further filtering of second level filter amplification circuit from a part of higher hamonic wave of described first order filter amplification circuit sine wave and frequency multiplication interference, amplify the peak-to-peak value of described sine wave signal; And by the further filtering of third level filter amplification circuit from a part of high frequency noise of second level filter amplification circuit sine wave and interference, amplify the peak-to-peak value of described sine wave to export the sine wave signal of an amplitude and specific.
In one embodiment, described push-pull circuit is configured to increase its driving force when not changing described amplitude and specific sine wave signal waveform.
In one embodiment, in the filter amplification circuit of the described driver unit second level, operational amplifier negative feedback termination enters 4V supply voltage, ensures that the intermediate value of signal is 4V, the peak-to-peak value of amplifying signal under the prerequisite that mean voltage is stable; In described third level filter amplification circuit, operational amplifier negative feedback end connects the output terminal of second level filter amplification circuit, guarantee that the intermediate value outputed signal is constant, and the enlargement factor suitably arranging amplifier obtains the peak-to-peak value of expectation.
In one embodiment, the differential amplifier circuit of described decoded portion after capacitance, carries out differential amplification the output signal at winding two ends, to ensure that the voltage after amplifying is in the scope that the AD of digital signal processor can know accurately identification.The positive input of differential amplifier connects 2.5V power supply, and be used for ensureing that the intermediate value of output signal is 2.5V, the signal after differential amplify is the sine wave of middle value stabilization.
In one embodiment, the rectification reverse circuit of described decoded portion carries out rectification the output waveform of differential amplifier circuit, for extracting the envelope of described sinusoidal echo and cosine echoed signal.
In one embodiment, the rectification reverse circuit of described decoded portion produces synchronous square-wave signal by Schmidt trigger, as a control signal of described rectification reverse circuit.
In one embodiment, the filtering circuit of described decoded portion adopts second-order low-pass filter to carry out filtering to the signal after upset, and obtain the effective value of signal, now signal has been level and smooth level signal, the positive input of amplifier connects 2.5V power supply, ensures that its reference voltage is 2.5V.
Excitation of the present utility model and decoder module have effectively saved cost, have only used some capacitance resistance wares and amplifier, reach the effect that decoding chip plays.Exciting circuit, by three grades of filtering, has filtered higher hamonic wave and frequency multiplication interference, has improve the accuracy of pumping signal, and signal stabilization, strong interference immunity.Suitably can revise filtering parameter for different square wave frequency, all reach desirable effect.Decoding circuit uses the links such as differential amplify, rectifying and wave-filtering, level conversion, the effective error reducing external interference and cause.
Accompanying drawing explanation
The utility model preferred embodiment is described further the utility model by reference to the accompanying drawings, wherein:
Fig. 1 is that rotary transformer and the utility model revolve the connection block diagram becoming and encourage with decoder module;
Fig. 2 is the theory diagram of exciting circuit;
Fig. 3 is the overall wiring diagram of exciting circuit;
Fig. 4 is the input signal of exciting circuit;
Fig. 5 is low-pass filtering amplifying circuit;
Fig. 6 is first order filtering circuit output waveform;
Fig. 7 is second level filter amplification circuit;
Fig. 8 is second level filter amplification circuit output waveform;
Fig. 9 is third level filter amplification circuit;
Figure 10 is third level filter amplification circuit output waveform;
Figure 11 is the circuit theory diagrams of driver output circuit;
Figure 12 is decoding circuit schematic diagram;
Figure 13 is decoding circuit block diagram;
Figure 14 is decoding circuit waveform input signal;
Figure 15 is differential amplifier circuit;
Figure 16 is differential amplifier circuit signal output waveform;
Figure 17 is rectification reverse circuit;
Figure 18 is rectification upset output waveform;
Figure 19 is voltage follower circuit;
Figure 20 is voltage follow output waveform;
Figure 21 is decoding filtering circuit;
Figure 22 is decoding filtering circuit output waveform;
Figure 23 is level shifting circuit;
Figure 24 is level conversion output waveform.
Embodiment
Consult Fig. 1, the preferred embodiment of this module 30 forms primarily of signal exciting circuit 31 and signal decoding circuit 32, the square wave excitation signal of signal exciting circuit 31 acquisition number word signal processor 10, be used for providing pumping signal for the rotary transformer 20 of permagnetic synchronous motor, signal decoding circuit 32 be used for back production to the sine of rotary transformer 20 export winding and cosine export the rotor of winding just, cosine position angle signal carries out signal conversion, finally exports digitized absolute position signal to digital signal processor 10.
Consult Fig. 2, the form of common use three grades of filter and amplifications of exciting circuit, final output can drive the signal of the excitation winding of rotary transformer, this implementation requirements square wave frequency is 10KHz, the intermediate value of sine wave output is 4.4V, and peak-to-peak value is [3.2V, 5.6V].Consult Fig. 3, the overall schematic diagram of exciting circuit, continuous three filtering of exciting circuit convert the very little sine wave of noise to square wave, this sinusoidal wave frequency is 10kHz, peak-to-peak value is [3.2V, 5.6V], then with push-pull circuit, the driving force of signal is increased.Consult Fig. 4, the utility model requires the square wave being input to exciting circuit, and its dutycycle is 50%, and after carrying out filtering, its mean voltage is 2.5V, and what one-level filtering adopted is active secondary low-pass filtering.
Consult Fig. 5, gain unit is that the operational amplifier of homophase amplification by realizes, and has
Circuit utilizes the Low ESR of operational amplifier to export and obtains V
o.Have by observing
At V
inode is sued for peace to electric current, namely
Cancellation V
i, then merging arrangement can obtain
S is replaced to obtain with j ω
Lowpass response H
lP, all step low-pass functions can be expressed as
H(jω)＝H
OLPH
LP(jω)
Canonical form, H in formula
oLPbe certain suitable constant, be called DC current gain, and
H (j ω) is represented by above formula canonical form, can obtain
H
OLP＝K
Make ω
2r
1c
1r
2c
2=(ω/ω
0)
2?
Consult Fig. 6, R1, R2 are 47k, C1, C2 is 1nF, and be 1.68k by calculating the enlargement factor K of this circuit, cutoff frequency is 3.3kHz, so obtain the sine wave that mean voltage is 4.2V, what filter is the harmonic wave of more than 33kHz, the output waveform of this circuit.
The output waveform of first-level filtering wave circuit has been the sine wave of standard, but considers that waveform exists serious times audio-frequency noise and higher hamonic wave, needs to continue filtering, and the peak-to-peak value of amplifying signal.
Consult Fig. 7, the difference of secondary filter circuit and first-level filtering wave circuit is filtering parameter, enlargement factor and mean voltage.
Consult Fig. 8, R5, R6 are 20k, C3, C4 are the bleeder circuit that 1nF secondary filter circuit increases 510R and 2kR in negative-feedback circuit, the intermediate value of output waveform is made to be retained to more than 4V, amplify intermediate value and peak-to-peak value, and cutoff frequency is 8K, what filter is the harmonic wave of times audio-frequency noise and more than 80K simultaneously, although filter effect is not too obvious, keep the peak-to-peak value little basis of intermediate value amplitude of variation being exaggerated waveform.,
Consult Fig. 9, although secondary filter amplifying circuit reduces times audio-frequency noise and high frequency noise, still there is more serious interference in waveform, in order to meet the requirements of intermediate value and peak-to-peak value, needing to carry out third level filter and amplification.The difference of three grades of filtering circuits and front two stage filter circuit is filtering parameter, enlargement factor and mean voltage.
Resistance R11, R12 are 15k, C5, C6 are 1nF, negative-feedback circuit connects secondary filter amplifying circuit and exports, the intermediate value of output waveform is kept to be stabilized in 4.4V, and amplifying peak-to-peak value further, cutoff frequency is 10kHz, and what filter is the noise of more than 100kHz, its output waveform noise is less, and intermediate value and peak-to-peak value all meet the demands.
Consult Figure 10, the signal after one pole filter and amplification is the signal that amplifier exports, and its driving force is very little, cannot the coil of Direct driver rotary transformer, so need to increase push-pull circuit, under the prerequisite not changing waveform, increases driving force.
Consult Figure 11, square wave through three grades of filter and amplifications, and increases driving force with push-pull circuit, obtains noise very little and can drive the pumping signal of the drive coil of rotary transformer.
Consult Figure 12, sinusoidal decoding circuit and cosine decoding circuit basically identical, be divided into differential amplifier circuit, reverse circuit and filtering circuit.
The sine of rotary transformer exports winding and exports sin+ and sin-two paths of signals, becoming after differential amplifier circuit with 2.5V is the sine wave of intermediate value, this sine wave is after rectification circuit, extract the envelope of signal, circuit considers into level and smooth level signal after filtering, finally carry out level conversion intermediate value is turned to be stabilized in 2.5V, obtain the sine value of rotor position angle.
Consult Figure 13, the sine of rotary transformer exports winding and exports cos+ and cos-two paths of signals, becoming after differential amplifier circuit with 2.5V is the sine wave of intermediate value, this sine wave is after rectification circuit, extract the envelope of signal, circuit considers into level and smooth level signal after filtering, finally carries out level conversion and intermediate value is stabilized in 2.5V, obtain the cosine value of rotor position angle.
Consult Figure 14, the input of the differential amplifier circuit part of decoding circuit is sin+ and sin-, and output take 2.5V as the sine wave of intermediate value
Consult Figure 15, the signal at the output winding two ends of rotary transformer inputs differential amplifier circuit after capacitance, and enlargement factor is 20, and it is the sine wave of intermediate value that the difference of differential input signal becomes with 2.5V after amplifying, and is input to rectification reverse circuit.
Consult Figure 16, the output waveform of differential amplifier circuit.
Consult Figure 17, the assignment of rectification reverse circuit not amplifying signal, but use Schmidt trigger to carry out signal upset, the trigger pip of Schmidt trigger uses a follow circuit
Consult Figure 18, Figure 19 and Figure 20, the input of this follow circuit is the output of differential amplifier circuit, compares with 2.5V, the square wave of output low level to be 0V high level be amplifier supply voltage.This square wave is added on the triggering pin of Schmidt trigger, trigger conducting during high level, and during low level, trigger disconnects, thus makes the sinusoidal envelope being input to rectification reverse circuit become steamed bun ripple.
Consult Figure 21 and Figure 22, the signal after rectification upset is input to low-pass filter circuit, and the cutoff frequency of this circuit is 1.5kHz, and what filter is the harmonic wave of more than 15KHz, output be level and smooth level.
Consult Figure 23 and Figure 24, the waveform that filtering circuit exports take 2.5V as benchmark, need the 2.5V this benchmark being transformed into standard, so with level shifting circuit, change, but consider that the components and parts of circuit have error, use 2.5V power supply as reference voltage, ensure that amplifier is when forward input and negative sense input are all 2.5V, amplifier exports 2.5V accurately.
The sine of rotary transformer exports winding and exports the identical filtering circuit of winding with cosine, finally obtains sine value and the cosine value of rotor position angle, and then tries to achieve rotor position angle by arc tangent.
Claims (8)
1. revolving of permanent-magnet synchronous motor rotor position angle becomes excitation and a decoder module, is electrically connected on the signal processor that produces Digital Square-Wave control signal and is embedded between the rotary transformer in permagnetic synchronous motor, it is characterized in that comprising:
Signal exciting circuit, for the digital signal from signal processor being converted to the sine wave signal that can drive rotary transformer, comprise: multiple-stage filtering amplifying circuit, for described digital signal being exported after repeatedly filter and amplification the sine wave signal of same frequency with it; And the push-pull circuit to be connected with the output terminal of described multi-stage filter circuit, for increasing the driving force of signal to drive the excitation winding of rotary transformer; And
Decoding circuit, the AC signal that process rotary transformer sine windings and cosine winding export is to draw the sine value of rotor position angle and cosine value and to export to described signal processor, comprise: differential amplifier circuit, receiving differential signal that described rotary transformer exports and exporting take 2.5V as the sine wave signal of intermediate value; Rectification reverse circuit, for extracting the envelope of described sinusoidal echo and cosine echoed signal; Filtering circuit, is filtered into straight level signal by the echoed signal after upset.
2. revolving of permanent-magnet synchronous motor rotor position angle according to claim 1 becomes excitation and decoder module, it is characterized in that: described filter amplification circuit is configured to carry out filtering with regard to the different frequency harmonic wave of described digital signal, and holding signal mean voltage is the peak-to-peak value of 4.4V and amplifying signal.
3. revolving of permanent-magnet synchronous motor rotor position angle according to claim 2 becomes excitation and decoder module, it is characterized in that: described filter amplification circuit comprises operational amplifier.
4. revolving of permanent-magnet synchronous motor rotor position angle according to claim 2 becomes excitation and decoder module, it is characterized in that: described multiple-stage filtering amplifying circuit is made up of three grades of filter amplification circuit, wherein said multiple-stage filtering amplifying circuit is configured to a part of higher hamonic wave by digital signal described in the filtering of first order filter amplification circuit, the intermediate value of waveform amplification and peak-to-peak value, sine wave output; By the further filtering of second level filter amplification circuit from a part of higher hamonic wave of described first order filter amplification circuit sine wave and frequency multiplication interference, amplify the peak-to-peak value of described sine wave signal; And by the further filtering of third level filter amplification circuit from a part of high frequency noise of second level filter amplification circuit sine wave and interference, amplify the peak-to-peak value of described sine wave to export an amplitude and specific sine wave signal.
5. revolving of permanent-magnet synchronous motor rotor position angle according to claim 4 becomes excitation and decoder module, it is characterized in that: described push-pull circuit is configured to increase its driving force when not changing described amplitude and specific sine wave signal waveform.
6. revolving of the permanent-magnet synchronous motor rotor position angle according to claim 3 or 4 becomes excitation and decoder module, it is characterized in that: in the filter amplification circuit of the described second level, operational amplifier negative feedback termination enters 4V voltage; In described third level filter amplification circuit, operational amplifier negative feedback end connects the output terminal of second level filter amplification circuit.
7. revolving of permanent-magnet synchronous motor rotor position angle according to claim 1 becomes excitation and decoder module, it is characterized in that: described rectification reverse circuit produces synchronous square-wave signal, as a control signal of described rectification reverse circuit by its Schmidt trigger.
8. revolving of permanent-magnet synchronous motor rotor position angle according to claim 1 becomes excitation and decoder module, it is characterized in that: described level shifting circuit is by connecting 2.5V power supply, so that output signal mid-point voltage is stable at 2.5V by the positive input of its operational amplifier.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420742790.6U CN204269070U (en) | 2014-12-01 | 2014-12-01 | A kind of change of revolving of measuring permanent-magnet synchronous motor rotor position angle encourages and decoder module |
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| CN201420742790.6U CN204269070U (en) | 2014-12-01 | 2014-12-01 | A kind of change of revolving of measuring permanent-magnet synchronous motor rotor position angle encourages and decoder module |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104406515A (en) * | 2014-12-01 | 2015-03-11 | 杭州湘滨电子科技有限公司 | Variable-reluctance stimulation and decoding module for measuring position angle of rotor of permanent magnet synchronous motor |
| CN105391368A (en) * | 2015-10-13 | 2016-03-09 | 沈阳东软医疗系统有限公司 | System for measuring position of treatment head diaphragm of linear accelerator |
| CN108599664A (en) * | 2018-05-30 | 2018-09-28 | 阳光电源股份有限公司 | A kind of the motor rotor position acquisition methods and system of rotary transformer |
| CN110873549A (en) * | 2018-08-30 | 2020-03-10 | 世倍特汽车电子(长春)有限公司 | Angle measuring system and angle measuring method |
| CN111025190A (en) * | 2019-11-28 | 2020-04-17 | 中国航空工业集团公司西安航空计算技术研究所 | Rotary transformer signal conditioning circuit and method |
-
2014
- 2014-12-01 CN CN201420742790.6U patent/CN204269070U/en not_active Withdrawn - After Issue
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104406515A (en) * | 2014-12-01 | 2015-03-11 | 杭州湘滨电子科技有限公司 | Variable-reluctance stimulation and decoding module for measuring position angle of rotor of permanent magnet synchronous motor |
| CN104406515B (en) * | 2014-12-01 | 2017-05-24 | 杭州湘滨电子科技有限公司 | Variable-reluctance stimulation and decoding module for measuring position angle of rotor of permanent magnet synchronous motor |
| CN105391368A (en) * | 2015-10-13 | 2016-03-09 | 沈阳东软医疗系统有限公司 | System for measuring position of treatment head diaphragm of linear accelerator |
| CN105391368B (en) * | 2015-10-13 | 2018-03-20 | 沈阳东软医疗系统有限公司 | A kind of system for measuring linear accelerator treatment head stop position |
| CN108599664A (en) * | 2018-05-30 | 2018-09-28 | 阳光电源股份有限公司 | A kind of the motor rotor position acquisition methods and system of rotary transformer |
| CN108599664B (en) * | 2018-05-30 | 2021-01-08 | 阳光电源股份有限公司 | Method and system for acquiring position of motor rotor of rotary transformer |
| CN110873549A (en) * | 2018-08-30 | 2020-03-10 | 世倍特汽车电子(长春)有限公司 | Angle measuring system and angle measuring method |
| CN111025190A (en) * | 2019-11-28 | 2020-04-17 | 中国航空工业集团公司西安航空计算技术研究所 | Rotary transformer signal conditioning circuit and method |
| CN111025190B (en) * | 2019-11-28 | 2021-11-09 | 中国航空工业集团公司西安航空计算技术研究所 | Rotary transformer signal conditioning circuit and method |
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Granted publication date: 20150415 Effective date of abandoning: 20170524 |
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