CN202364188U - Filter circuit used for measuring voltage of generator rotor - Google Patents
Filter circuit used for measuring voltage of generator rotor Download PDFInfo
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- CN202364188U CN202364188U CN2011204592024U CN201120459202U CN202364188U CN 202364188 U CN202364188 U CN 202364188U CN 2011204592024 U CN2011204592024 U CN 2011204592024U CN 201120459202 U CN201120459202 U CN 201120459202U CN 202364188 U CN202364188 U CN 202364188U
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Abstract
The utility model discloses a filter circuit used for measuring a voltage of a generator rotor. The filter circuit used for measuring the voltage of the generator rotor includes an AC component processing circuit used for extracting input signals and negating, and an adder circuit. A channel of a primary input signal connects with an input terminal of the AC component processing circuit while the other channel of the primary input signal output signals of the AC component processing circuit are input into the adder circuit respectively. After the superposition by the adder circuit, the adder circuit outputs a filtered primary input signal DC component. The filter circuit used for measuring the voltage of the generator rotor in the utility model can filter AC component in generator rotor input voltage signals. Therefore, not only the filtering effect of filtering the AC component is guaranteed, but also the quickest response in filtering is guaranteed.
Description
Technical field
The utility model relates to a kind of filter circuit, particularly a kind of filter circuit that is used for the generator amature voltage measurement.
Background technology
The generator amature voltage waveform is six wave head situations of rule; Promptly in a power frequency period, there is the consistent wave head of six wave form; Rotor voltage is carried out Fourier change and to find, comprised the alternating current component of DC component and six multiple subharmonic in the rotor voltage waveform.Under a lot of situation, in the detection of generator amature voltage, electric parameters to be detected has always comprised DC component and alternating current component.For many Equipment Control; The existence of alternating current component badly influences the precision and the accuracy of measurement result; For the alternating current component in the filtering detection limit; In most cases all introduced filter circuit,, the filter effect of the alternating current component in the acquired signal has directly been had influence on the reliability of systematic sampling precision and The whole control system particularly for the system of only gathering the DC component in the rotor voltage.Alternating current component has also been brought the problem of response speed simultaneously at the proportion in whole detection limit though the introducing of filter circuit has decayed to a great extent.For the detection limit that the alternating current component frequency spectrum is confirmed, testing process can be carried out Filtering Processing through software.For the detection limit of alternating current component spectral change, carry out Filtering Processing program complicacy through software.The method that realizes above-mentioned filter effect at present mainly contains following two kinds.
First kind for realizing through the hardware circuit design low pass filter.Its principle is that detection limit is passed through a low pass filter, and the alternating current component in the signal is significantly decayed.Because the existence of low-order harmonic, there are contradiction in the cut-off frequency of filtering system, attenuation amplitude and system response time.When cut-off frequency is lower, when attenuation amplitude was big, system response time was also big, having influence on the control real-time of sampling and relevant control system.When cut-off frequency higher, attenuation amplitude hour, though system response time can shorten, the alternating current component that contains in the detection limit is more, sampling precision is not high.
Second kind for realizing through software design approach.When the alternating current component frequency spectrum that contains in the detection limit fixedly the time, can carry out Filtering Processing through program.According to Shannon's sampling theorem; If the signal after the sampling has comprised by all information of sampled signal; Be reduced into the signal before the sampling if promptly the signal after the sampling can be complete, then sample frequency must be not less than the twice of the highest frequency component respective frequencies that is comprised in the sampled signal.Therefore, a lot of software approachs realize that filtering all needs the low pass filter of external hardware circuit to be used.Through external hardware circuit filtering high fdrequency component, realize the filtering of low frequency component again through software algorithm.The filtering of low frequency component and low pass filter have all increased time constant filter.
The utility model content
The purpose of the utility model provides a kind of filter circuit that is used for the generator amature voltage measurement, fast the alternating current component in the filtering generator amature input voltage signal.
The purpose of the utility model realizes through following technical measures:
A kind of filter circuit that is used for the generator amature voltage measurement comprises the alternating current component treatment circuit, the add circuit that are used to extract input signal alternating current component and negate; Original input signal one road inserts the input of said alternating current component treatment circuit; The output signal of another road of original input signal and said alternating current component treatment circuit is imported said add circuit respectively; Superimposed through add circuit, said add circuit is exported filtered original input signal DC component.
Said alternating current component treatment circuit comprises extraction circuit, the negate circuit that is used to extract the input signal alternating current component; Said original input signal is successively through said extraction circuit and the output of negate circuit.
Said negate circuit comprises first order compensating circuit and the second level compensating circuit that is used for input signal is carried out phase compensation; The output signal of said extraction circuit is successively through said first order compensating circuit and the output of second level compensating circuit.
Said extraction circuit comprises first amplifier, isolation capacitance, first resistance and second resistance; Said isolation capacitance one end is the input of said extraction circuit; Insert said original input signal; The isolation capacitance other end is leaded up to said first grounding through resistance; Another road is connected to the in-phase input end of said first amplifier, and said second resistance is connected between the inverting input and output of said first amplifier, and the output of said first amplifier is the output of said extraction circuit.
Said first order compensating circuit comprises second amplifier, first building-out capacitor, the 3rd resistance and the 4th resistance; Said the 3rd resistance one end is the input of said first order compensating circuit; Be connected to the output of said extraction circuit; The 3rd resistance other end is connected to the in-phase input end of said second amplifier; Said the 4th resistance is connected between the inverting input and output of said second amplifier, and the inverting input of said second amplifier is through the said first building-out capacitor ground connection, and the output of said second amplifier is the output of said first order compensating circuit;
Said second level compensating circuit comprises the 3rd amplifier, second building-out capacitor, the 5th resistance and the 6th resistance; Said the 5th resistance one end is the input of said second level compensating circuit; Be connected to the output of said first order compensating circuit; The 5th resistance other end is connected to the inverting input of said the 3rd amplifier; Said second building-out capacitor is connected between the inverting input and output of said the 3rd amplifier; The in-phase input end of said the 3rd amplifier is through said the 6th grounding through resistance, and the output of said the 3rd amplifier is the output of said second level compensating circuit, is connected to one road input of said add circuit.
The resistance of said first resistance, second resistance, the 3rd resistance, the 4th resistance, the 5th resistance and the 6th resistance equates; The appearance value of said isolation capacitance, first building-out capacitor and second building-out capacitor equates.
As a kind of embodiment of utility model, also comprise being used for the buffer circuit that original input signal is isolated input; Said original input signal divides two-way to import said alternating current component treatment circuit and add circuit respectively through said buffer circuit.
Compared with prior art, the utlity model has following beneficial effect:
The filter circuit of the utility model adopts the alternating current component treatment circuit; The generator amature input voltage signal is carried out DC component filtering processing and alternating current component reverse process; And the alternating current component after will be reverse superposes through add circuit with source signal, eliminated the alternating current component in the generator amature input voltage signal, output DC component; So; The filter circuit of the utility model is the alternating current component in the filtering generator amature input voltage signal fast, has both guaranteed the filtration result to alternating current component, has guaranteed the response the most fast of filtering again.
Description of drawings
Below in conjunction with accompanying drawing and specific embodiment the utility model is done further to specify:
Fig. 1 is the theory diagram of the utility model filter circuit specific embodiment;
Fig. 2 is the circuit theory diagrams of the utility model filter circuit specific embodiment;
Fig. 3 ~ 7 are the test waveform figure of the utility model filter circuit specific embodiment under the input AC component of five kinds of different frequencies;
Wherein, figure intermediate cam waveform is the signal waveform of oscilloscope CH1 passage, and figure cathetus waveform is the signal waveform of oscilloscope CH2 passage.
Embodiment
Fig. 1 shows the filter circuit that the utility model is used for the generator amature voltage measurement, comprises the alternating current component treatment circuit, the add circuit that are used to extract input signal alternating current component and negate; Original input signal one road inserts the input of said alternating current component treatment circuit; The output signal of another road of original input signal and said alternating current component treatment circuit is imported said add circuit respectively; Superimposed through add circuit, said add circuit is exported filtered original input signal DC component.
Wherein, a kind of execution mode of alternating current component treatment circuit comprises the extraction circuit, the negate circuit that are used to extract the input signal alternating current component; Original input signal is successively through said extraction circuit and the output of negate circuit.And the negate circuit can be, comprises the first order compensating circuit and the second level compensating circuit that are used for input signal is carried out phase compensation; The output signal of said extraction circuit is successively through said first order compensating circuit and the output of second level compensating circuit.
The filter circuit that the utility model is used for the generator amature voltage measurement also can increase the buffer circuit that is used for original input signal isolation input; Said original input signal divides two-way to import said alternating current component treatment circuit and add circuit respectively through said buffer circuit.
As shown in Figure 2; The filter circuit that is used for the generator amature voltage measurement of the optimum embodiment of the utility model; Comprise buffer circuit A5, alternating current component treatment circuit and add circuit A4, wherein the alternating current component treatment circuit comprises the extraction circuit A1 that is used to extract the input signal alternating current component, first order compensating circuit A2 and the second level compensating circuit A3 that is used for input signal is carried out phase compensation.
Extract circuit A1 and comprise the first amplifier U1, isolation capacitance C2, first resistance R 1 and second resistance R 2; Said isolation capacitance C2 one end is the input of said extraction circuit A1; The isolation capacitance C2 other end is leaded up to said first resistance R, 1 ground connection; Another road of the isolation capacitance C2 other end is connected to the in-phase input end 5 of the said first amplifier U1; Said second resistance R 2 is connected between the inverting input 6 and output 7 of the said first amplifier U1, and the output 7 of the said first amplifier U1 is the output of said extraction circuit A1.
First order compensating circuit A2 comprises the second amplifier U2, the first building-out capacitor C3, the 3rd resistance R 3 and the 4th resistance R 4; Said the 3rd resistance R 3 one ends are the input of said first order compensating circuit A2; Be connected to the output of said extraction circuit A1; The 3rd resistance R 3 other ends are connected to the in-phase input end 10 of the said second amplifier U2; Said the 4th resistance R 4 is connected between the inverting input 9 and output 8 of the said second amplifier U2, and the inverting input 9 of the said second amplifier U2 is through the said first building-out capacitor C3 ground connection, and the output 8 of the said second amplifier U2 is the output of said first order compensating circuit A2.
Second level compensating circuit A3 comprises the 3rd amplifier U3, the second building-out capacitor C4, the 5th resistance R 5 and the 6th resistance R 6; Said the 5th resistance R 5 one ends are the input of said second level compensating circuit A3; Be connected to the output of said first order compensating circuit A2; The 5th resistance R 5 other ends are connected to the inverting input 13 of said the 3rd amplifier U3; The said second building-out capacitor C4 is connected between the inverting input 13 and output 14 of said the 3rd amplifier U3; The in-phase input end 12 of said the 3rd amplifier U3 is through said the 6th resistance R 6 ground connection, and the output 14 of said the 3rd amplifier U3 is the output of said second level compensating circuit A3.
Wherein, the resistance of first resistance R 1, second resistance R 2, the 3rd resistance R 3, the 4th resistance R 4, the 5th resistance R 5 and the 6th resistance R 6 equates; The appearance value of isolation capacitance C2, the first building-out capacitor C3 and the second building-out capacitor C4 equates.
Add circuit A4 comprises four high guaily unit U4, the 7th resistance R 7, the 8th resistance R 8 and the 9th resistance R 9; One end of said the 7th resistance R 7 and the 8th resistance R 8 is connected; The other end of said the 7th resistance R 7 and the 8th resistance R 8 is divided into the first via input and the second road input of said add circuit A4; The second road input of add circuit A4 is connected to the output of second level compensating circuit A3; The tie point of said the 7th resistance R 7 and the 8th resistance R 8 is connected to the in-phase input end 3 of said four high guaily unit U4; Said the 9th resistance R 9 is connected between the inverting input 2 and output 1 of said four high guaily unit U4, and the output 1 of said four high guaily unit U4 is the output of said add circuit A4; Said the 7th resistance R 7 and the 8th resistance R 8 resistances equate.Wherein, the positive feeder ear 4 of said four high guaily unit U4 meets positive 12V power supply VCC12P and negative 12V power supply VCC12N respectively with negative feeder ear 11.
Buffer circuit A5 comprises the 5th amplifier U5, capacitor C 1, current-limiting resistance R11 and the tenth resistance R 10; The in-phase input end 16 of the 5th amplifier U5 is through current-limiting resistance R11 and capacitor C 1 ground connection; The tie point of current-limiting resistance R11 and capacitor C 1 is the input of said isolation input circuit A5; Input Vin as the present embodiment filter circuit; Be used to insert original input signal, the tenth resistance R 10 is connected between the inverting input 15 and output 17 of said the 5th amplifier U5, and the output 17 of said the 5th amplifier U5 is the output of said isolation input circuit A5; One the road is connected to the input that extracts circuit A1, and another road is connected to the first via input of add circuit A4.Wherein, the positive feeder ear 19 of said the 5th amplifier U5 meets positive 12V power supply VCC12P and negative 12V power supply VCC12N respectively with negative feeder ear 18.
The operation principle that present embodiment is used for the filter circuit of generator amature voltage measurement is: because the resistance of first resistance R 1, second resistance R 2, the 3rd resistance R 3, the 4th resistance R 4, the 5th resistance R 5 and the 6th resistance R 6 equates; The resistance of getting them here is R; Again because the appearance value of isolation capacitance C2, the first building-out capacitor C3 and the second building-out capacitor C4 equates that the appearance value of getting them here is C, draws thus; The transfer function of block isolating circuit A1 is j ω RC/ (1+j ω RC); The transfer function of first order compensating circuit A2 is 1+j ω RC, and the transfer function of second level compensating circuit A3 is-1/j ω RC that the transfer function of three links multiplies each other the back for-1; The transfer function that is present embodiment alternating current component treatment circuit is-1; Its multiplication factor for the alternating current component of different frequency is-1, and present embodiment alternating current component treatment circuit can be to comprising the input signal of alternating current component and DC component, carries out the filtering DC component and alternating current component is carried out-1 reverse process obtaining an Opposed crossing amount.Like this, for the alternating current component of different frequency, its amplitude-frequency characteristic is all consistent with phase-frequency characteristic.The Opposed crossing amount that the rotor voltage signal of input obtains after the alternating current component processing circuit processes; Identical with the alternating current component size of the rotor voltage signal of input and phase place is opposite; Both through add circuit A4 superimposed after; Can offset alternating current component, the DC component in the remaining rotor voltage signal is through the output output of add circuit A4.
The triangular signal that below passes through to setover with the band of five groups of different frequencies is as input signal; The checking present embodiment is used for the filter effect of the filter circuit of generator amature voltage measurement; Can know that through Fourier's variation the DC component and the alternating current component that comprise in the DC component that comprises in this signal and alternating current component composition and the rotor voltage are similar.Therefore, replace the rotor voltage actual waveform to test with triangular wave, test result has science and preciseness, can reflect that present embodiment is used for the filter effect of the filter circuit of generator amature voltage measurement to generator amature voltage.
As shown in Figure 3; The input that is used for the filter circuit of generator amature voltage measurement to present embodiment; When input comprises the generator amature voltage signal (shown in CH1 passage waveform among the figure) of 3V DC component and 3V (peak value), 300Hz (frequency) triangular wave alternating current component, the filter circuit output 3V direct current signal (shown in CH2 passage waveform in scheming) of present embodiment.
As shown in Figure 4; The input that is used for the filter circuit of generator amature voltage measurement to present embodiment; When input comprises the generator amature voltage signal (shown in CH1 passage waveform among the figure) of 3V DC component and 3V (peak value), 2kHz (frequency) triangular wave alternating current component, the filter circuit output 3V direct current signal (shown in CH2 passage waveform in scheming) of present embodiment.
As shown in Figure 5; The input that is used for the filter circuit of generator amature voltage measurement to present embodiment; When input comprises the generator amature voltage signal (shown in CH1 passage waveform among the figure) of 3V DC component and 3V (peak value), 10kHz (frequency) triangular wave alternating current component, the filter circuit output 3V direct current signal (shown in CH2 passage waveform in scheming) of present embodiment.
As shown in Figure 6; The input that is used for the filter circuit of generator amature voltage measurement to present embodiment; When input comprises the generator amature voltage signal (shown in CH1 passage waveform among the figure) of 3V DC component and 3V (peak value), 10kHz (frequency) triangular wave alternating current component, the filter circuit output 3V direct current signal (shown in CH2 passage waveform in scheming) of present embodiment.
As shown in Figure 7; The input that is used for the filter circuit of generator amature voltage measurement to present embodiment; When input comprises the generator amature voltage signal (shown in CH1 passage waveform among the figure) of 3V DC component and 3V (peak value), 250kHz (frequency) triangular wave alternating current component, the filter circuit output 3V direct current signal (shown in CH2 passage waveform in scheming) of present embodiment.
Can know by above-mentioned Fig. 3 ~ 7; When the frequency shift of input AC component; The direct current signal of present embodiment filter circuit output keeps stablizing constant, and its value equals the value of DC component in the input signal, and the filter circuit of having verified present embodiment is the conclusion of different frequency alternating current component in the filtering input signal fast; The passband that has proved this filter circuit simultaneously is very wide, can satisfy the Filtering Processing requirement of random signal.
The execution mode of the utility model is not limited thereto; According to foregoing; Ordinary skill knowledge and customary means according to this area; Do not breaking away under the above-mentioned basic fundamental thought of the utility model prerequisite, equivalent modifications, replacement or change that the utility model can also be made other various ways all can realize the utility model purpose.
Claims (7)
1. a filter circuit that is used for the generator amature voltage measurement is characterized in that: comprise the alternating current component treatment circuit, the add circuit that are used to extract original input signal alternating current component and negate; Original input signal one road inserts the input of said alternating current component treatment circuit; The output signal of another road of original input signal and said alternating current component treatment circuit is imported said add circuit respectively; Superimposed through add circuit, said add circuit is exported filtered original input signal DC component.
2. according to the said filter circuit that is used for the generator amature voltage measurement of claim 1, it is characterized in that: said alternating current component treatment circuit comprises extraction circuit, the negate circuit that is used to extract the input signal alternating current component; Said original input signal is successively through said extraction circuit and the output of negate circuit.
3. according to the said filter circuit that is used for the generator amature voltage measurement of claim 2, it is characterized in that: said negate circuit comprises first order compensating circuit and the second level compensating circuit that is used for input signal is carried out phase compensation; The output signal of said extraction circuit is successively through said first order compensating circuit and the output of second level compensating circuit.
4. according to the said filter circuit that is used for the generator amature voltage measurement of claim 2, it is characterized in that: said extraction circuit comprises first amplifier, isolation capacitance, first resistance and second resistance; Said isolation capacitance one end is the input of said extraction circuit; Insert said original input signal; The isolation capacitance other end is leaded up to said first grounding through resistance; Another road is connected to the in-phase input end of said first amplifier, and said second resistance is connected between the inverting input and output of said first amplifier, and the output of said first amplifier is the output of said extraction circuit.
5. according to the said filter circuit that is used for the generator amature voltage measurement of claim 3, it is characterized in that:
Said first order compensating circuit comprises second amplifier, first building-out capacitor, the 3rd resistance and the 4th resistance; Said the 3rd resistance one end is the input of said first order compensating circuit; Be connected to the output of said extraction circuit; The 3rd resistance other end is connected to the in-phase input end of said second amplifier; Said the 4th resistance is connected between the inverting input and output of said second amplifier, and the inverting input of said second amplifier is through the said first building-out capacitor ground connection, and the output of said second amplifier is the output of said first order compensating circuit;
Said second level compensating circuit comprises the 3rd amplifier, second building-out capacitor, the 5th resistance and the 6th resistance; Said the 5th resistance one end is the input of said second level compensating circuit; Be connected to the output of said first order compensating circuit; The 5th resistance other end is connected to the inverting input of said the 3rd amplifier; Said second building-out capacitor is connected between the inverting input and output of said the 3rd amplifier; The in-phase input end of said the 3rd amplifier is through said the 6th grounding through resistance, and the output of said the 3rd amplifier is the output of said second level compensating circuit, is connected to one road input of said add circuit.
6. according to claim 4 or the 5 said filter circuits that are used for the generator amature voltage measurement, it is characterized in that: the resistance of said first resistance, second resistance, the 3rd resistance, the 4th resistance, the 5th resistance and the 6th resistance equates; The appearance value of said isolation capacitance, first building-out capacitor and second building-out capacitor equates.
7. according to the said filter circuit that is used for the generator amature voltage measurement of claim 1, it is characterized in that: also comprise being used for the buffer circuit that original input signal is isolated input; Said original input signal divides two-way to import said alternating current component treatment circuit and add circuit respectively through said buffer circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011204592024U CN202364188U (en) | 2011-11-18 | 2011-11-18 | Filter circuit used for measuring voltage of generator rotor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011204592024U CN202364188U (en) | 2011-11-18 | 2011-11-18 | Filter circuit used for measuring voltage of generator rotor |
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| CN202364188U true CN202364188U (en) | 2012-08-01 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN2011204592024U Expired - Fee Related CN202364188U (en) | 2011-11-18 | 2011-11-18 | Filter circuit used for measuring voltage of generator rotor |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109387279A (en) * | 2018-12-19 | 2019-02-26 | 南京工程学院 | A kind of detection circuit of the vibration signal of pair of turbine generator final stage |
| CN110441603A (en) * | 2019-08-13 | 2019-11-12 | 西安西驰电气股份有限公司 | A kind of earth leakage search/lockout sample circuit and detection method |
| CN111579857A (en) * | 2020-04-21 | 2020-08-25 | 赵红雁 | Digital compensation type voltage sampling circuit and method for instrument |
-
2011
- 2011-11-18 CN CN2011204592024U patent/CN202364188U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109387279A (en) * | 2018-12-19 | 2019-02-26 | 南京工程学院 | A kind of detection circuit of the vibration signal of pair of turbine generator final stage |
| CN110441603A (en) * | 2019-08-13 | 2019-11-12 | 西安西驰电气股份有限公司 | A kind of earth leakage search/lockout sample circuit and detection method |
| CN110441603B (en) * | 2019-08-13 | 2021-07-20 | 西安西驰电气股份有限公司 | Electric leakage blocking sampling circuit and detection method |
| CN111579857A (en) * | 2020-04-21 | 2020-08-25 | 赵红雁 | Digital compensation type voltage sampling circuit and method for instrument |
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Effective date of registration: 20131129 Address after: Shiling Town, Huadu District, Guangzhou City, Guangdong province 511450 Yufeng Road No. 16 Patentee after: Qingtian Industry Co., Ltd., Guangzhou Address before: 510302 Xingang West Road, Guangdong, China, No. 204, No. Patentee before: China National Electric Apparatus Research Institute Co., Ltd. |
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| CF01 | Termination of patent right due to non-payment of annual fee | ||
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Granted publication date: 20120801 Termination date: 20201118 |