CN106970260A - A kind of phase voltage Acquisition Circuit of frequency converter output and the measuring method of amplitude - Google Patents
A kind of phase voltage Acquisition Circuit of frequency converter output and the measuring method of amplitude Download PDFInfo
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- CN106970260A CN106970260A CN201710367559.1A CN201710367559A CN106970260A CN 106970260 A CN106970260 A CN 106970260A CN 201710367559 A CN201710367559 A CN 201710367559A CN 106970260 A CN106970260 A CN 106970260A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/25—Arrangements for measuring currents or voltages or for indicating presence or sign thereof using digital measurement techniques
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/40—Arrangements for reducing harmonics
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Abstract
The invention discloses the measuring method of a kind of phase voltage Acquisition Circuit of frequency converter output and amplitude, its phase voltage Acquisition Circuit includes phase voltage output end, the phase voltage output end is connected with high-voltage signal to be changed into the difference channel of low-voltage signal, the difference channel output end is connected with supercircuit, sinusoidal signal is superimposed+1.5V signals by the supercircuit, after the supercircuit output end is connected with first-order filtering circuit, limiter diode, export to DSP AD acquisition ports ADCIN1.The measuring method of its amplitude, comprises the following steps：AD collections are enabled, collection ABC three-phase phase voltages, calculated three groups of phase voltage amplitudes, judged to count and whether be more than n, find current amplitude maximum, minimum value, output voltage amplitude and sum, subtract maximum, minimum value, take average, obtain output voltage U the present invention can save the hardware such as voltage sensor or voltage transformer in actual applications, it is cost-effective, the mode of connection of simplified control system, saves installing space.
Description
Technical field
The invention belongs to a kind of Acquisition Circuit and its measuring method, and in particular to a kind of phase voltage collection of frequency converter output
The measuring method of circuit and amplitude.
Background technology
At present, output voltage amplitude required in Frequency Converter Control is general mutual by using voltage sensor or voltage
Sensor is obtained.
For output signal be AC signal sensor, it is ensured that the real-time of signal acquisition, but the AC signal without
Method is applied in the frequency converter using amplitude control or display, it is necessary to AC signal is changed into direct current signal by algorithm, typically
The algorithm of use has maximum value process or the root-mean-square value method of average etc., but the real-time of these algorithms is very poor, nor is applied to
In the frequency converter of cline frequency change.
For using output signal for the voltage sensor of direct current signal, the collection of output voltage amplitude can be completed, it is real
Show AC signal inversion of direct current signal, but the real-time of system can be deteriorated, and cost is higher, and its volume is generally large, using output
Frequency range is smaller, is not suitable for the application of a wide range of output frequency frequency converter.
The content of the invention
The present invention proposes that the purpose is to provide a kind of phase electricity of frequency converter output to solve the problem of prior art is present
Press the measuring method of Acquisition Circuit and amplitude.
The technical scheme is that：A kind of phase voltage Acquisition Circuit of frequency converter output, including phase voltage output end, institute
State phase voltage output end and be connected with high-voltage signal to be changed into the difference channel of low-voltage signal, the difference channel output end is with being superimposed
Circuit is connected, and sinusoidal signal is superimposed+1.5V signals, the supercircuit output end and first-order filtering electricity by the supercircuit
After road, limiter diode are connected, export to DSP AD acquisition ports ADCIN1.
The A of phase voltage, which is connected, is connected to resistance R1 1 pin, resistance R1 2 pin and amplifier amplifier U1A 2 pin, resistance R3
1 pin, electric capacity C1 1 pin are connected, and resistance R3 2 pin are connected to 2 pin of amplifier amplifier U1A 1 pin, resistance R5 1 pin and C1,
The N poles of phase voltage are connected to resistance R2 1 pin, resistance R2 2 pin and operational amplifier U1A 3 pin, resistance R4 1 pin, electric capacity
C2 1 pin is connected, and resistance R4 2 pin are connected with C2 2 pin, simulation ground AGND, resistance R5 2 pin and resistance R6 2 pin, computing
Amplifier UIB 5 pin are connected, and resistance R6 1 pin is connected to+3V, operational amplifier UIB 6 pin, 1 pin phase of 7 pin and resistance R7
Connect, resistance R7 2 pin are connected with electric capacity C3 1 pin, diode D1 1 pin, diode D2 2 pin, and be connected to DSP AD and adopt
Collect mouth ADCIN1, electric capacity C3 2 pin, diode D2 1 pin are connected with simulation ground AGND, and diode D1 2 pin are connected to+3V.
The resistance R4 two ends are parallel with electric capacity C2, resistance R4, electric capacity C2 composition low-pass first order filter.
The resistance R3 two ends are parallel with electric capacity C1, resistance R3, electric capacity C1 composition low-pass first order filter.
4 pin of the operational amplifier U1A are connected to -15V, and U1A 8 pin are connected to+15V.
Using the measuring method of the amplitude of the above-mentioned phase voltage Acquisition Circuit for stating frequency converter output, comprise the following steps：
(I) AD collections are enabled
Enable DSP AD conversion, all initialization of variable；
(II) gathers ABC three-phase phase voltages
It is U by ADCIN1, ADCIN2, ADCIN3 mouthfuls of collection AN, BN, CN three-phase phase voltagesa、Ub、Uc, three-phase subtracts respectively
Go to be superimposed DC quantity；
(III) calculates three groups of phase voltage amplitudes
For the symmetrical frequency converter of three-phase output voltage, its any time output voltage can be expressed as
Wherein Ua、Ub、UcAny time output voltage instantaneous value is represented, U represents output voltage amplitude；
It is available by equation (1)
According to sin2wt+cos2Wt=1, by deriving, the expression formula that can draw any time output voltage amplitude is
Or
Or
According to the phase voltage U gathered in formula (3) and step (II)a、Ub、UcOutput voltage amplitude U1, U2, U3 are obtained,
U1, U2, U3, which average, obtains U；
(IV) judges to count whether be more than n
Judge whether to reach times of collection n, if times of collection is not up to times of collection n, perform step (V), if
Times of collection reaches times of collection n, then performs step (VII)；
(V) finds current amplitude maximum, minimum value
Find respectively when the maximum and minimum value in former groups of amplitudes；
(VI) output voltage amplitude is summed
Accumulation several groups of output voltage amplitudes of superposition；
(VII) subtracts maximum, minimum value, takes average
The accumulated value of n group voltage magnitudes is subtracted into wherein maximum, minimum value, then average；
(VIII) obtains output voltage U
Output voltage U is obtained, and is exported.
The present invention can save the hardware such as voltage sensor or voltage transformer in actual applications, cost-effective, simplify
The mode of connection of control system, saves installing space.The present invention can be instantaneous by any two-phase output voltage at any time
It is worth to output voltage amplitude, it is possible to achieve the conversion of the AC signal of any time to direct current signal.Filter Jing Guo rear class again
Ripple mode, in identical sampling time section, can increase the calculation times of output voltage amplitude, so that it is steady to improve output voltage
It is qualitative.The present invention can be calculated output voltage amplitude in real time by the output voltage instantaneous value detected in real time, and real-time is high.
Brief description of the drawings
Fig. 1 is the circuit diagram of phase voltage Acquisition Circuit in the present invention；
Fig. 2 is the method flow diagram of amplitude measuring method in the present invention.
Embodiment
Hereinafter, referring to the drawings and embodiment the present invention is described in detail：
As shown in figure 1, a kind of phase voltage Acquisition Circuit of frequency converter output, including phase voltage output end, the phase voltage
Output end is connected with high-voltage signal to be changed into the difference channel of low-voltage signal, the difference channel output end and supercircuit phase
Even, sinusoidal signal is superimposed+1.5V signals, the supercircuit output end and first-order filtering circuit, amplitude limit by the supercircuit
After diode is connected, export to DSP AD acquisition ports ADCIN1.
The A of phase voltage, which is connected, is connected to resistance R1 1 pin, resistance R1 2 pin and amplifier amplifier U1A 2 pin, resistance R3
1 pin, electric capacity C1 1 pin are connected, and resistance R3 2 pin are connected to 2 pin of amplifier amplifier U1A 1 pin, resistance R5 1 pin and C1,
The N poles of phase voltage are connected to resistance R2 1 pin, resistance R2 2 pin and operational amplifier U1A 3 pin, resistance R4 1 pin, electric capacity
C2 1 pin is connected, and resistance R4 2 pin are connected with C2 2 pin, simulation ground AGND, resistance R5 2 pin and resistance R6 2 pin, computing
Amplifier UIB 5 pin are connected, and resistance R6 1 pin is connected to+3V, operational amplifier UIB 6 pin, 1 pin phase of 7 pin and resistance R7
Connect, resistance R7 2 pin are connected with electric capacity C3 1 pin, diode D1 1 pin, diode D2 2 pin, and be connected to DSP AD and adopt
Collect mouth ADCIN1, electric capacity C3 2 pin, diode D2 1 pin are connected with simulation ground AGND, and diode D1 2 pin are connected to+3V.
The resistance R4 two ends are parallel with electric capacity C2, resistance R4, electric capacity C2 composition low-pass first order filter.
The resistance R3 two ends are parallel with electric capacity C1, resistance R3, electric capacity C1 composition low-pass first order filter.
4 pin of the operational amplifier U1A are connected to -15V, and U1A 8 pin are connected to+15V.
As shown in Fig. 2 the measuring method of the amplitude of the phase voltage Acquisition Circuit exported using above-mentioned frequency converter, including it is following
Step：
(I) AD collections are enabled
Enable DSP AD conversion, all initialization of variable；
(II) gathers ABC three-phase phase voltages
It is U by ADCIN1, ADCIN2, ADCIN3 mouthfuls of collection AN, BN, CN three-phase phase voltagesa、Ub、Uc, three-phase subtracts respectively
Go to be superimposed DC quantity；
(III) calculates three groups of phase voltage amplitudes
For the symmetrical frequency converter of three-phase output voltage, its any time output voltage can be expressed as
Wherein Ua、Ub、UcAny time output voltage instantaneous value is represented, U represents output voltage amplitude；
It is available by equation (1)
According to sin2wt+cos2Wt=1, by deriving, the expression formula that can draw any time output voltage amplitude is
Or
Or
According to the phase voltage U gathered in formula (3) and step (II)a、Ub、UcOutput voltage amplitude U1, U2, U3 are obtained,
U1, U2, U3, which average, obtains U；
(IV) judges to count whether be more than n
Judge whether to reach times of collection n, if times of collection is not up to times of collection n, perform step (V), if
Times of collection reaches times of collection n, then performs step (VII)；
(V) finds current amplitude maximum, minimum value
Find respectively when the maximum and minimum value in former groups of amplitudes；
(VI) output voltage amplitude is summed
Accumulation several groups of output voltage amplitudes of superposition；
(VII) subtracts maximum, minimum value, takes average
The accumulated value of n group voltage magnitudes is subtracted into wherein maximum, minimum value, then average；
(VIII) obtains output voltage U
Output voltage U is obtained, and is exported.
Formula (3) in step (III) can be seen that at any time, only it is to be understood that any two-phase output voltage is instantaneous
Value, it becomes possible to obtain output voltage amplitude, and it is unrelated with frequency converter output frequency.
Simultaneously to improve the anti-interference of output voltage amplitude, while using filtering mode, improving algorithm interference free performance.
Frequency converter output voltage frequency is 50Hz, then its cycle is 20ms, and AD collection timer periods are 0.1ms, if adopting
With integration rms algorithm, times of collection n is at least 200, and the output voltage values that could complete a cycle are calculated, and in order to carry
High system rejection to disturbance, generally requires the data volume in several cycles, and such times of collection needs to greatly improve, the real-time of system
It can reduce.
The present invention, under equal conditions, due to algorithm using any two-phase output voltage instantaneous value with regard to output electricity can be obtained
Pressure amplitude value, therefore collection period can also obtain multiple output voltage amplitudes when being less than a cycle T, times of collection n is less than 200,
System can also obtain regulated output voltage value, then by multi collect output voltage, remove maximum, minimum value, average
It is filtered, because times of collection is greatly increased, output voltage interference free performance is also greatly improved.
The present invention can save the hardware such as voltage sensor or voltage transformer in actual applications, cost-effective, simplify
The mode of connection of control system, saves installing space.The present invention can be instantaneous by any two-phase output voltage at any time
It is worth to output voltage amplitude, it is possible to achieve the conversion of the AC signal of any time to direct current signal.Filter Jing Guo rear class again
Ripple mode, in identical sampling time section, can increase the calculation times of output voltage amplitude, so that it is steady to improve output voltage
It is qualitative.The present invention can be calculated output voltage amplitude in real time by the output voltage instantaneous value detected in real time, and real-time is high.
Claims (6)
1. a kind of phase voltage Acquisition Circuit of frequency converter output, including phase voltage output end, it is characterised in that：The phase voltage is defeated
Go out end with high-voltage signal to be changed into the difference channel of low-voltage signal to be connected, the difference channel output end is connected with supercircuit,
Sinusoidal signal is superimposed+1.5V signals, the supercircuit output end and first-order filtering circuit, the pole of amplitude limit two by the supercircuit
After pipe is connected, export to DSP AD acquisition ports ADCIN.
2. a kind of phase voltage Acquisition Circuit of frequency converter output according to claim 1, it is characterised in that：The A of phase voltage
It is connected and is connected to resistance R1 1 pin, resistance R1 2 pin and amplifier amplifier U1A 2 pin, resistance R3 1 pin, electric capacity C1 1 pin phase
Even, resistance R3 2 pin are connected to 2 pin of amplifier amplifier U1A 1 pin, resistance R5 1 pin and C1, and the N poles of phase voltage are connected to
Resistance R2 1 pin, resistance R2 2 pin are connected with operational amplifier U1A 3 pin, resistance R4 1 pin, electric capacity C2 1 pin, resistance
R4 2 pin are connected with C2 2 pin, simulation ground AGND, 5 pin phases of resistance R5 2 pin and resistance R6 2 pin, operational amplifier UIB
Even, resistance R6 1 pin is connected to+3V, and operational amplifier UIB 6 pin, 7 pin are connected with resistance R7 1 pin, resistance R7 2 pin and
Electric capacity C3 1 pin, diode D1 1 pin, diode D2 2 pin are connected, and are connected to DSP AD acquisition port ADCIN1, electric capacity
C3 2 pin, diode D2 1 pin are connected with simulation ground AGND, and diode D1 2 pin are connected to+3V.
3. a kind of phase voltage Acquisition Circuit of frequency converter output according to claim 2, it is characterised in that：The resistance R4
Two ends are parallel with electric capacity C2, resistance R4, electric capacity C2 composition low-pass first order filter.
4. a kind of phase voltage Acquisition Circuit of frequency converter output according to claim 2, it is characterised in that：The resistance R3
Two ends are parallel with electric capacity C1, resistance R3, electric capacity C1 composition low-pass first order filter.
5. a kind of phase voltage Acquisition Circuit of frequency converter output according to claim 2, it is characterised in that：The computing is put
Big device U1A 4 pin are connected to -15V, and U1A 8 pin are connected to+15V.
6. a kind of measuring method of the amplitude of the phase voltage Acquisition Circuit of frequency converter output described in application the claims 1, its
It is characterised by：Comprise the following steps：
(I) AD collections are enabled
Enable DSP AD conversion, all initialization of variable；
(II) gathers ABC three-phase phase voltages
It is U to gather AN, BN, CN three-phase phase voltage respectively by ADCIN1, ADCIN2, ADCIN3 mouthfulsa、Ub、Uc, three-phase subtracts respectively
Go to be superimposed DC quantity；
(III) calculates three groups of phase voltage amplitudes
For the symmetrical frequency converter of three-phase output voltage, its any time output voltage can be expressed as
Wherein Ua、Ub、UcAny time output voltage instantaneous value is represented, U represents output voltage amplitude；
It is available by equation (1)
According to sin2wt+cos2Wt=1, by deriving, the expression formula that can draw any time output voltage amplitude is
Or
Or
According to the phase voltage U gathered in formula (3) and step (II)a、Ub、UcObtain output voltage amplitude U1, U2, U3, U1,
U2, U3, which average, obtains U；
(IV) judges to count whether be more than n
Judge whether to reach times of collection n, if times of collection is not up to times of collection n, perform step (V), if collection
Number of times reaches times of collection n, then performs step (VII)；
(V) finds current amplitude maximum, minimum value
Find respectively when the maximum and minimum value in former groups of amplitudes；
(VI) output voltage amplitude is summed
Accumulation several groups of output voltage amplitudes of superposition；
(VII) subtracts maximum, minimum value, takes average
The accumulated value of n group voltage magnitudes is subtracted into wherein maximum, minimum value, then average；
(VIII) obtains output voltage U
Output voltage U is obtained, and is exported.
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| CN201710367559.1A CN106970260B (en) | 2017-05-23 | 2017-05-23 | Phase voltage acquisition circuit output by frequency converter and amplitude measuring and calculating method |
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| CN201710367559.1A CN106970260B (en) | 2017-05-23 | 2017-05-23 | Phase voltage acquisition circuit output by frequency converter and amplitude measuring and calculating method |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107634753A (en) * | 2017-10-24 | 2018-01-26 | 西安航空制动科技有限公司 | The interface circuit and its design method of aircraft anti-sliding control box signal output point |
| CN108414818A (en) * | 2018-03-30 | 2018-08-17 | 核工业理化工程研究院 | A kind of Acquisition Circuit and frequency converter for measuring high-frequency ac voltage |
| CN108512437A (en) * | 2018-03-29 | 2018-09-07 | 核工业理化工程研究院 | A kind of frequency quick adjustable frequency converter and control method |
| CN108562788A (en) * | 2018-05-23 | 2018-09-21 | 广东伊莱斯电机有限公司 | A kind of control method improving analog loopback sampling precision |
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| CN107634753A (en) * | 2017-10-24 | 2018-01-26 | 西安航空制动科技有限公司 | The interface circuit and its design method of aircraft anti-sliding control box signal output point |
| CN108512437A (en) * | 2018-03-29 | 2018-09-07 | 核工业理化工程研究院 | A kind of frequency quick adjustable frequency converter and control method |
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| CN106970260B (en) | 2023-08-18 |
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