CN102998525A - Multifunctional single-phase electric energy measuring circuit and automatic ammeter calibrating method thereof - Google Patents
Multifunctional single-phase electric energy measuring circuit and automatic ammeter calibrating method thereof Download PDFInfo
- Publication number
- CN102998525A CN102998525A CN2011102730132A CN201110273013A CN102998525A CN 102998525 A CN102998525 A CN 102998525A CN 2011102730132 A CN2011102730132 A CN 2011102730132A CN 201110273013 A CN201110273013 A CN 201110273013A CN 102998525 A CN102998525 A CN 102998525A
- Authority
- CN
- China
- Prior art keywords
- calibration
- current
- electric energy
- metering circuit
- multifunctional electric
- 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.)
- Granted
Links
Images
Landscapes
- Measurement Of Current Or Voltage (AREA)
Abstract
The invention discloses a multifunctional single-phase electric energy measuring circuit and an automatic ammeter calibrating method thereof. The measuring circuit comprises three paths of analog-to-digital converters, three groups of effective value calculating units, power calculating units and digital frequency converting units. Active energy, quadergy, apparent energy and power factors based on power line current and zero line current can be calculated simultaneously, current and voltage effective values can also be calculated simultaneously, and power stealing instruction can be generated according to differences between effective values or active power of two paths of current. In addition, an automatic calibrating module is embedded in the measuring circuit, system detuning and gain error can be calibrated automatically, ammeter calibrating process of an intelligent ammeter can be simplified greatly, and different deviation among different circuits can be calibrated.
Description
Technical field
The present invention relates to a kind of single-phase multifunctional electric energy metering circuit and meter calibration method, but particularly relate to a kind of single-phase multifunctional electric energy metering circuit and ammeter automatic calibrating method thereof of auto-adjustment, belong to the Electric Energy Metering Technology field.
Background technology
Electric energy metrical mainly multiplies each other the voltage and current signal of input according to the time, obtaining the information that power changes along with the time is instantaneous power, supposes that current and voltage signals is sine function, and have phase differential Ф that the relation of current and voltage signals is as follows:
Then power p is:
If phase differential Ф=0, then
If phase differential Ф ≠ 0, then
Wherein p (t) is called the instantaneous power signal, and desirable p (t) includes only two parts: instantaneous active power
And instantaneous reactive power
Wherein instantaneous active power comprises direct current component: VI*cos (Ф) and frequency are
AC portion:
So P=VI*cos (Ф), Q=VI*sin (Ф), S=VI is respectively average active power (watts), average reactive power (VARS) and applied power (VA), and wherein average active power is the primary metering object of electric energy meter.
Corresponding power just obtains corresponding energy signal through the integration of certain hour, i.e. the corresponding meritorious energy of active power, the corresponding quadergy of reactive power, and the corresponding apparent energy of applied power.
If the non-cosine function of current and voltage signals then can expand into the harmonic wave of cosine function with signal by Fourier transform, can calculate by above-mentioned p (t)=v (t) * i (t) equally, no longer describe in detail herein.
Fig. 1 is that the model that ADI company produces is the Organization Chart of the electric energy computation chip of ADE7755, as shown in Figure 1, this electric energy computation chip comprises two-way analog-digital converter (ADC), 1 group of multiplier, one group of low-pass filter (LPF), one road integrator (Integrator) and a railway digital frequency converter, this electric energy computation chip directly directly drives register accumulation active energy, signal processing circuit adopts digital circuit, antijamming capability is strong, it can directly link to each other from the sensor of different journey amounts, can reach degree of accuracy and the stable purpose simplifying Interface design and improve power measurement, thereby be widely used, yet, this electric energy computation chip only has the function of active energy metering, can't measure reactive energy, apparent electric energy and power factor etc. can't comprehensively be estimated user's power quality.
In addition, because electric energy computation chip and external circuit tend to cause certain otherness, in order to eliminate this otherness, often need electric energy meter is calibrated.Typical type of calibration generally comprises: gain calibration, imbalance offset calibration and phase alignment.Traditional single-phase electronic energy meter correction method is normally when the resistor network of design voltage sampling circuit, the resistance in series of 5 to 7 fixed resistance value is set, and then put the resistance in series adjustment network that 8 to 10 resistances are successively decreased according to the order of 2n, these resistance are called adjusting resistance.Each resistance is provided with the short circuit point, then the percentage error that shows according to tester, by short circuit or disconnect short circuit and put to adjust the resistance that the resistance of suitable resistance changes the voltage sampling loop, thereby change the voltage sample value, so that the low frequency calibration pulse of metering circuit output is close as far as possible with the recurrence interval of standard scale threshold value or equate, thereby reach the purpose of calibration.This method realizes by pure hardware, need to reserve the short circuit point more than at least 8 in the design process, in order to error can be adjusted in the scope of requirement, it is large to take the pcb board area, increased hardware cost, regulate the speed slowly extensive giving birth in the production run, labour intensity is large, needs the mileometer adjustment personnel that certain experience is arranged.
The problem that exists for solving above-mentioned traditional single phase electronic electric energy meter correction method, the patent No. that Jiangsu Kaouwanhong Electronics Co., Ltd. proposes then provides a kind of auto-adjustment method for 200810196038 Chinese patent, it saves the adjustable resistance network, reduced hardware spending, and can increase substantially calibration efficient, reduce labour intensity, full-automatic operation can be realized more accurately calibration.But above-mentioned correction method is only applicable to measure traditional single-phase electronic energy meter of active energy, can't proofread and correct reactive energy, apparent electric energy, effective value and power factor etc.
In sum, there are the problem that can't measure and proofread and correct reactive energy, apparent electric energy, effective value and power factor etc. in the ic for energy metering of prior art and calibration steps thereof as can be known, therefore, be necessary to propose improved technological means in fact, solve this problem.
Summary of the invention
There is the shortcoming that to measure and to proofread and correct reactive energy, apparent electric energy, effective value and power factor etc. for overcoming prior art, purpose one of of the present invention is to provide a kind of single-phase multifunctional electric energy metering circuit and ammeter automatic calibrating method thereof, it can measure meritorious energy, quadergy and apparent energy and power factor based on live wire electric current and neutral line current simultaneously, simultaneously measurable electric current and voltage effective value.
Another purpose of the present invention is to provide a kind of single-phase multifunctional electric energy metering circuit and automatic calibrating method thereof, and it can produce the stealing indication according to the effective value of two-way electric current or the difference of active power.
An again purpose of the present invention is to provide a kind of single-phase multifunctional electric energy metering circuit and automatic calibrating method thereof, it is by built-in automatic calibration module, imbalance and gain error that not only can self-correcting system, the calibration flow process of intelligent electric meter is simplified greatly, and can be revised the different deviations between different circuit.
For reaching above-mentioned and other purpose, the invention provides a kind of single-phase multifunctional electric energy metering circuit, be applied to an intelligent electric meter system, comprise at least:
No. three analog-digital converters, be respectively applied to receive live wire current sampling signal, neutral line current sampled signal and voltage sampling signal, and this live wire current sampling signal of the simulation that will receive, this neutral line current sampled signal and this voltage sampling signal be converted to digital signal, to obtain the first current sampling data, the second current sampling data and voltage sample data;
Three groups of effective value computing units receive respectively this first current sampling data, this second current sampling data and this voltage sample data, and it is obtained the first current effective value, the second current effective value and voltage effective value after computing respectively;
The Power arithmetic unit multiplies each other this first current sampling data, this second current sampling data respectively with these voltage sample data, obtain instantaneous active power, and this instantaneous active power is exported average active power through a cic filter; With multiplying each other respectively with this first current sampling data, this second current sampling data again behind these voltage sample data phase shift 90 degree, obtain instantaneous reactive power, and this instantaneous reactive power is exported average reactive power through a cic filter; This first current effective value and this second current effective value are multiplied each other with this voltage effective value respectively, obtain applied power; And
The numerical frequency converting unit, be used for this instantaneous active power, this instantaneous reactive power and this applied power integration by certain hour, obtaining meritorious energy, quadergy and apparent energy, and this average active power and average reactive power are converted to output of pulse signal through numeral after frequency inverted, shunt running judgement and frequency modulation (PFM).
Further, this single-phase multifunctional electric energy metering circuit also comprises a stealing judging unit, this stealing judging unit is accepted average active power or the current effective value of two-way electric current, by the average active power of comparison two-way electric current or the size of current effective value, produce the stealing indication and offer main control MCU.
Further, every group of effective value computing unit comprises squaring circuit, cic filter and root circuit at least, output this first current effective value, this second current effective value and this voltage effective value after this first current sampling data, this second current sampling data and this voltage sample data that receive are calculated by this squaring circuit, this cic filter and this root circuit respectively
Further, between every road analog-digital converter and every group of effective value computing unit, this single-phase multifunctional electric energy metering circuit also comprises a decimation filter of digital, phase alignment circuit and Hi-pass filter, with the high frequency noise in the elimination digital signal and DC current gain.
Further, before this live wire current sampling signal, this neutral line current sampled signal and this voltage sampling signal are input to this No. three analog-digital converter, also can amplify each sampled signal through a programmable gain amplifier respectively.
Further, this single-phase multifunctional electric energy metering circuit comprises that also an automatic calibration module is to revise gain error and the offset error of analog-digital converter, this automatic calibration module comprises system-gain calibration and two kinds of patterns of unbalance of system calibration at least, when this single-phase multifunctional electric energy metering circuit under the automatic calibration pattern, send the instruction of system-gain calibration and unbalance of system calibration for this single-phase multifunctional electric energy metering circuit by this main control MCU, after the calibration flow process is finished, this single-phase multifunctional electric energy metering circuit generates calibration and finishes ready look-at-me, and the value that the notice main control MCU reads corresponding register stores in the storer; When normal mode of operation, main control MCU reads calibration data from this storer, writes in the corresponding metering circuit calibration register.
Further, this metering circuit calibration register comprises the DC maladjustment calibration register, exchanges mistuning calibration function register and DC current gain calibration register.
Further, under this system-gain calibration mode, this automatic calibration module provides accurately reference voltage as the reference signal by outside precision voltage sources, and the outside input pin of this single-phase multifunctional electric energy metering circuit is connect this outside precision voltage sources, and by a common mode voltage ground connection.
Further, under this unbalance of system calibration mode, this automatic calibration module is the outside input pin short circuit of this this single-phase multifunctional electric energy metering circuit, and by a common mode voltage ground connection.
Further, after the Hi-pass filter of three passages, the value of this DC maladjustment calibration register is revised the output of this Hi-pass filter by a totalizer respectively.
Further, the result after the value of this DC current gain calibration register is calibrated DC maladjustment by a multiplier respectively revises, with this first current sampling data, this second current sampling data and this voltage sample data that needing to obtain.
Further, after the extraction of square root circuit, the value of this interchange mistuning calibration function register is revised the output of this extraction of square root circuit by a totalizer respectively.
Further, this single-phase multifunctional electric energy metering circuit comprises a digital interface unit, this digital interface unit be used for and main control MCU between special delivery calibration parameter and metering result, it can be I2C, SPI, UART or single-wire communication bus.
For reaching above-mentioned and other purpose, the present invention also provides a kind of automatic calibrating method of ammeter, is applied to an intelligent electric meter system that comprises single-phase multifunctional electric energy metering circuit, comprises the steps: at least
Carry out before the calibration procedure, make this single-phase multifunctional electric energy metering circuit be in effective status, calibrate accordingly look-at-me and be reset;
The calibration reference signal of automatic calibration module is input to the analog input pin;
Main control MCU sends corresponding calibration command to the digital interface unit of metering circuit; And
This single-phase multifunctional electric energy metering circuit is finished internal calibration according to calibration command, the result is write corresponding calibration register and produce calibration to finish look-at-me indication calibration and finish.
Further, this calibration command is 8 order of the bit, and wherein every difference setting has been specified different calibration modes.
Further, this calibration mode comprises the DC maladjustment calibration mode, exchanges mistuning calibration function pattern, DC current gain calibration mode and ac gain calibration mode.
Further, exchange under the mistuning calibration function pattern the outside input pin short circuit ground connection of this single-phase multifunctional electric energy metering circuit with this at this DC maladjustment calibration mode
Further, if the calibration mode of this calibration command is the DC maladjustment calibration mode, the mean value of the first current sampling data, the second current sampling data and voltage sample data in the nearest computation period is stored respectively into the DC maladjustment calibration register.
Further, if the calibration mode of this calibration command stores respectively the mean value of the first current effective value, the second current effective value and voltage effective value in the nearest computation period into interchange mistuning calibration function register for exchanging the mistuning calibration function pattern.
Further, under this DC current gain calibration mode and this ac gain calibration mode, the outside input pin of this single-phase multifunctional electric energy metering circuit connects the direct current calibrating signal.
Further, if the calibration mode of this calibration command is the DC current gain calibration mode, get inverse by the mean value of the transient voltage sampled value in the computation period and store the DC current gain calibration register into, then this mean value is adjusted, making corresponding instantaneous voltage sampled value is 1.
Further, if the calibration mode of this calibration command is the ac gain calibration mode, get inverse by the mean value of transient voltage sampled value in the computation period and store in the DC current gain calibration register, then this mean value is adjusted, making corresponding effective value value is 0.6.
Compared with prior art, a kind of single-phase multifunctional electric energy metering circuit of the present invention and automatic calibrating method thereof are by three tunnel analog digital digital quantizers, three groups of effective value computing units, power calculation unit and numerical frequency converting unit can be measured the meritorious energy based on live wire electric current and neutral line current simultaneously, quadergy and apparent energy and power factor, measurable electric current and voltage effective value, and can produce the stealing indication according to the effective value of two-way electric current or the difference of active power, simultaneously the present invention is also by built-in automatic calibration module, imbalance and gain error that not only can self-correcting system, the calibration flow process of intelligent electric meter is simplified greatly, and can be revised the different deviations between different circuit.
Description of drawings
Fig. 1 is for using a kind of intelligent electric meter system schematic of the present invention;
Fig. 2 is the circuit structure diagram of the preferred embodiment of a kind of single-phase multifunctional electric energy metering circuit of the present invention;
Fig. 3 is the synoptic diagram of ADC gain and offset error among Fig. 2;
Fig. 4 is system-gain calibration mode and the unbalance of system calibration mode outer signal synoptic diagram of the auto-calibration circuits that adopts of the present invention;
Fig. 5 is the present invention's automatic gain and mistuning calibration function synoptic diagram;
Fig. 6 is the process flow diagram of automatic calibrating method of the present invention's electric energy meter.
Embodiment
Below by specific instantiation and accompanying drawings embodiments of the present invention, those skilled in the art can understand other advantage of the present invention and effect easily by content disclosed in the present specification.The present invention also can be implemented or be used by other different instantiation, and the every details in this instructions also can be based on different viewpoints and application, carries out various modifications and change under the spirit of the present invention not deviating from.
Fig. 1 is for using a kind of intelligent electric meter system schematic of the present invention, and this intelligent electric meter system comprises current-voltage sampling module 101, the present invention's ic for energy metering 102, main control MCU 103, lcd drive chip 104, infrared communication interface 105, RS485 communicating circuit 106, power management module 107 and calibration impulse output circuit 108.
Fig. 2 is the circuit structure diagram of the preferred embodiment of a kind of single-phase multifunctional electric energy metering circuit of the present invention, as shown in Figure 2, a kind of single-phase multifunctional electric energy metering circuit of the present invention, mainly be used in single-phase-two-wire or three line intelligent electric meters, be applied to the intelligent electric meter system of Fig. 1, it comprises at least: No. three analog-digital converters 201, three groups of effective value computing units 202, power calculation unit 203 and numerical frequency converting units 204.
No. three analog-digital converters 201 are connected with the current-voltage sampling module 101 of intelligent electric meter system, it is used for receiving respectively live wire current sampling signal (such as I1p and I1n), neutral line current sampled signal (I1p and I1n) and voltage sampling signal (for example Vp and Vn), and will to receive analog signal conversion be digital signal, with obtain respectively the first current sampling data I1, the second current sampling data I2 and and voltage sample data V; Three groups of effective value computing units 202 receive respectively the first current sampling data I1, the second current sampling data I2 and voltage sample data V, and it is obtained the first current effective value I after computing respectively
1RMS, the second current effective value I
2RMSAnd V
RMSMore particularly, every group of effective value computing unit also comprises squaring circuit, cic filter and root circuit, after namely the first current sampling data I1, the second current sampling data I2 and voltage sample data are passed through the calculating of squaring circuit, cic filter, root circuit respectively, obtain the first current effective value I
1RMS, the second current effective value I
2RMSAnd voltage effective value V
RMSPower arithmetic unit 203 is with the first current sampling data I1, the second current sampling data I2 multiplies each other with voltage sample data V respectively, obtain instantaneous active power P1 and P2, like this with instantaneous active power P1 and P2 through a cic filter, just obtain average active power (P1avg and P2avg), calculating for instantaneous reactive power, Power arithmetic unit 203 is spent voltage sample data V through digital filter (Hilbert wave filter) phase shift 90, and then with the first current sampling data I1, the second current sampling data I2 multiplies each other respectively, just obtain instantaneous reactive power Q1 and Q2, like this with instantaneous reactive power Q1 and Q2 through a cic filter, just obtain average reactive power (Q1avg and Q2avg), for the calculating of applied power, Power arithmetic unit 203 is with the first current effective value I
1RMSObtain at convenience applied power S1 and S2 mutually with voltage effective value VRMS respectively with the second current effective value I2RMS, average active power (P1avg and P2avg) can obtain power factor (PF1 and PF2) divided by applied power (S1/S2); Numerical frequency converting unit 204 is used for active power (P1/P2), reactive power (Q1/Q2) and applied power (S1/S2) are by the integration of certain hour, obtain to get meritorious energy, quadergy and apparent energy, and active power and inactivity process is digital to frequency inverted, be converted to output of pulse signal (CF1/CF2/CF3) after shunt running judgement and the frequency modulation (PFM), pulse output (CF1/CF2/CF3) can be simple by one, single line, thereby the optics isolated port is connected to the calibration of finishing electric energy meter on the outside calibration equipment, it should be noted that at this, the present invention's metering circuit inside comprises special delivery calibration parameter and metering result between a digital interface unit and the main control MCU, digital interface unit can be I2C, SPI, UART or single-wire communication bus etc.
Better, a kind of single-phase multifunctional electric energy metering circuit of the present invention also comprises a stealing judging unit 205, it receives average active power (P1avg and P2avg) or the current effective value (the first current effective value I1RMS and the second current effective value I2RMS) of two-way electric current, compare the average active power of two-way electric current or the size of current effective value by comparing two-way, stealing judging unit 205 can produce the stealing indication main control MCU is provided, and there is stealing in prompting.
Be better realization the present invention, a kind of single-phase multifunctional electric energy metering circuit of the present invention is after No. three analog-digital converters 201 are digital signal with analog signal conversion, also comprise decimation filter of digital, phase alignment circuit (PHCAL) and Hi-pass filter, its objective is high frequency noise and DC current gain in the elimination digital signal, obtain current sampling data and the voltage sample data of needs, in addition, at live wire current sampling signal (such as I1p and I1n), neutral line current sampled signal (I1p and I1n) and voltage sampling signal (for example Vp and Vn) are input to before No. three analog-digital converters 201, also can amplify sampled signal through a programmable gain amplifier (PGA).
Because the analog to digital converter (ADC) of metering circuit inside is converted to digital signal to voltage signal and the current signal after sampling, ADC is essentially the interface between the analog and digital signal, so the error characteristics of ADC have determined the measuring accuracy of whole electric energy metrical.Fig. 3 is the synoptic diagram of ADC gain and offset error among Fig. 2, we can find out from Fig. 3, ideal curve is y=(m1) x, curve with gain error is y=(m2) x, and the actual curve of the present invention with full range error is y=(m2) x+b, as seen the transformation curve of actual ADC exists gain error and offset error, because the existence of process deviation, the ADC transformation curve of different chips is also slightly variant, so the present invention comprises that also an automatic calibration module 206 is to revise all above-mentioned deviations.Automatic calibration module 206 comprises system-gain calibration and two kinds of patterns of unbalance of system calibration in preferred embodiment of the present invention, and the unbalance of system calibration comprises the DC maladjustment calibration and exchanges two kinds of patterns of mistuning calibration function, and the system-gain calibration also comprises DC current gain calibration and ac gain calibration.Fig. 4 is system-gain calibration mode and the unbalance of system calibration mode outer signal synoptic diagram of the auto-calibration circuits that adopts of the present invention.Wherein, under the system-gain calibration mode, automatic calibration module 206 provides accurately reference voltage as the reference signal by the accurate voltage source in outside, the outside input pin (IN+ and IN-) that is about to metering circuit meets a reference voltage source Vcc, and by common mode voltage ground connection, under unbalance of system religion quasi-mode, automatic calibration module 206 is the outside input pin short circuit of metering circuit, and by common mode voltage ground connection.When the present invention's metering circuit under the automatic calibration pattern, send the instruction of system-gain calibration and unbalance of system calibration to metering circuit by main control MCU, after the calibration flow process is finished, the present invention's metering circuit generates calibration and finishes ready look-at-me, and the value that the notice main control MCU reads corresponding register stores in the storer (such as EEPROM); When normal mode of operation, main control MCU reads calibration data from storer, write in the corresponding metering circuit calibration register (such as DC maladjustment calibration register I1dcoff, I2dcoff and Vdcoff, gain calibration register I1gn, I2gn and Vgn, exchange mistuning calibration function register I1acoff, I2acoff and Vacoff), thereby revise gain error and the offset error of inner ADC, measured accurately the result.Please continue with reference to Fig. 2, specifically, in preferred embodiment of the present invention, at the Hi-pass filter (HPF) of three passages afterwards, DC maladjustment calibration register (I1dcoff, I2dcoff and Vdcoff) value by a totalizer output of Hi-pass filter is revised respectively, gain calibration register (I1gn, I2gn and Vgn) value then by a multiplier result after the DC maladjustment calibration is further revised respectively, with current sampling data (the first current sampling data I1 and the second current sampling data I2) and the voltage sample data V that needing to obtain; After the extraction of square root circuit, the output that the value that exchanges mistuning calibration function register (I1acoff, I2acoff and Vacoff) is then split squaring circuit by a totalizer is respectively revised, to obtain accurately current effective value (the first current effective value I
1RMS, the second current effective value I
2RMS) and voltage effective value V
RMSIn addition, for instantaneous active power (P1 and P2), instantaneous reactive power (Q1 and Q2), before it carried out integration, the value of DC maladjustment calibration register (P1off and P2off and Q1off and Q2off) was revised instantaneous active power (P1 and P2), instantaneous reactive power (Q1 and Q2) by a totalizer respectively.
Fig. 5 is the present invention's automatic gain and mistuning calibration function synoptic diagram.Fig. 6 is the process flow diagram of automatic calibrating method of the present invention's electric energy meter.Below will cooperate Fig. 5 and Fig. 6 that the present invention's automatic calibrating method is elaborated.
Electric energy automatic calibrating method among the present invention, support is for DC maladjustment and the gain calibration of microchronometer value, interchange mistuning calibration function for effective value, because each passage has independently gain and mistuning calibration function register, therefore the calibration of three passages can be carried out simultaneously, and the present invention's electric energy automatic calibrating method comprises the steps that calibration sequence is as follows:
Step 602 is input to the analog input pin with the calibration reference signal of automatic calibration module 206;
Step 604 after metering circuit is finished internal calibration and deposited the result in corresponding calibration register, produces calibration and finishes look-at-me, and the indication calibration is finished, if be necessary, can read calibration value this moment by digital interface from corresponding gain/imbalance register.
The detailed process that the following is each calibration mode is described:
Direct current with exchange the mistuning calibration function pattern under, outside input pin short circuit ground connection,
The flow process of the calibration of DC maladjustment is as follows: the initial value of internal gain calibration register is 1.0, then the mean value of the instantaneous sampling value in the nearest computation period (N sample value) is stored into DC maladjustment calibration register (I1dcoff, I2dcoff and Vdcoff) in, under normal mode of operation, the value of DC maladjustment amount will be deducted from signalling channel, with the direct current offset of bucking-out system.
Exchange the calibration of imbalance similarly, only instantaneous value is replaced with effective value.
Under the DC current gain calibration mode, outside input pin connects the direct current calibrating signal, then will get inverse by the mean value of the interior transient voltage sampled value of a computation period (N sample value) and store (I1gn, I2gn and Vgn) in the DC current gain calibration register into, then this mean value is adjusted, making corresponding instantaneous sampling value is 1.Therefore, execute DC current gain calibration after, during direct current calibrating signal level when the input signal DC level equals to calibrate, the reading of transient voltage register is full scale value 1.0.
The starting point of alternating voltage gain calibration algorithm is to adjust voltage channel gain register value, so that the value of the effective value register of corresponding input end calibration reference signal level is 0.6.Calibrating signal adds externally to be inputted on the positive and negative pin, and level determines (had better not surpass 70% of maximum input signal amplitude, will overflow if surpass then instantaneous value metering result) by the user.Then will get inverse by the mean value of the interior transient voltage sampled value of a computation period (N sample value) and store in the DC current gain calibration register, and then this mean value be adjusted, making corresponding effective value value is 0.6.Therefore, execute ac gain calibration after, when the interchange calibrating signal level of input signal during for calibration, the metering result of effective value is 0.6.
As seen, by foregoing circuit and method, a kind of single-phase multifunctional electric energy metering circuit of the present invention and automatic calibrating method thereof can measure the meritorious energy based on live wire electric current and neutral line current simultaneously, quadergy and apparent energy and power factor, measurable electric current and voltage effective value, and can produce the stealing indication according to the effective value of two-way electric current or the difference of active power, imbalance and gain error that simultaneously the built-in automatic calibration module of the present invention can update the system, the calibration flow process of intelligent electric meter is simplified greatly, not only can automatically finish, need not manual intervention, and can revise the different deviations between different circuit.
Claims (22)
1. a single-phase multifunctional electric energy metering circuit is applied to an intelligent electric meter system, comprises at least:
No. three analog-digital converters, be respectively applied to receive live wire current sampling signal, neutral line current sampled signal and voltage sampling signal, and this live wire current sampling signal of the simulation that will receive, this neutral line current sampled signal and this voltage sampling signal be converted to digital signal, to obtain the first current sampling data, the second current sampling data and voltage sample data;
Three groups of effective value computing units receive respectively this first current sampling data, this second current sampling data and this voltage sample data, and it is obtained the first current effective value, the second current effective value and voltage effective value after computing respectively;
The Power arithmetic unit multiplies each other this first current sampling data, this second current sampling data respectively with these voltage sample data, obtain instantaneous active power, and this instantaneous active power is exported average active power through a cic filter; With multiplying each other respectively with this first current sampling data, this second current sampling data again behind these voltage sample data phase shift 90 degree, obtain instantaneous reactive power, and this instantaneous reactive power is exported average reactive power through a cic filter; This first current effective value and this second current effective value are multiplied each other with this voltage effective value respectively, obtain applied power; And
The numerical frequency converting unit, be used for this instantaneous active power, this instantaneous reactive power and this applied power integration by certain hour, obtaining meritorious energy, quadergy and apparent energy, and this average active power and average reactive power are converted to output of pulse signal through numeral after frequency inverted, shunt running judgement and frequency modulation (PFM).
2. single-phase multifunctional electric energy metering circuit as claimed in claim 1, it is characterized in that: this single-phase multifunctional electric energy metering circuit also comprises a stealing judging unit, this stealing judging unit is accepted average active power or the current effective value of two-way electric current, by the average active power of comparison two-way electric current or the size of current effective value, produce the stealing indication and offer main control MCU.
3. single-phase multifunctional electric energy metering circuit as claimed in claim 1, it is characterized in that: every group of effective value computing unit comprises squaring circuit, cic filter and root circuit at least, output this first current effective value, this second current effective value and this voltage effective value after this first current sampling data, this second current sampling data and this voltage sample data that receive are calculated by this squaring circuit, this cic filter and this root circuit respectively
4. single-phase multifunctional electric energy metering circuit as claimed in claim 3, it is characterized in that: between every road analog-digital converter and every group of effective value computing unit, this single-phase multifunctional electric energy metering circuit also comprises a decimation filter of digital, phase alignment circuit and Hi-pass filter, with the high frequency noise in the elimination digital signal and DC current gain.
5. single-phase multifunctional electric energy metering circuit as claimed in claim 4, it is characterized in that: before this live wire current sampling signal, this neutral line current sampled signal and this voltage sampling signal are input to this No. three analog-digital converter, also can amplify each sampled signal through a programmable gain amplifier respectively.
6. single-phase multifunctional electric energy metering circuit as claimed in claim 4, it is characterized in that: this single-phase multifunctional electric energy metering circuit comprises that also an automatic calibration module is to revise gain error and the offset error of analog-digital converter, this automatic calibration module comprises system-gain calibration and two kinds of patterns of unbalance of system calibration at least, when this single-phase multifunctional electric energy metering circuit under the automatic calibration pattern, send the instruction of system-gain calibration and unbalance of system calibration for this single-phase multifunctional electric energy metering circuit by this main control MCU, after the calibration flow process is finished, this single-phase multifunctional electric energy metering circuit generates calibration and finishes ready look-at-me, and the value that the notice main control MCU reads corresponding register stores in the storer; When normal mode of operation, main control MCU reads calibration data from this storer, writes in the corresponding metering circuit calibration register.
7. single-phase multifunctional electric energy metering circuit as claimed in claim 6 is characterized in that: this metering circuit calibration register comprises the DC maladjustment calibration register, exchanges mistuning calibration function register and DC current gain calibration register.
8. single-phase multifunctional electric energy metering circuit as claimed in claim 7, it is characterized in that: under this system-gain calibration mode, this automatic calibration module provides accurately reference voltage as the reference signal by outside precision voltage sources, the outside input pin of this single-phase multifunctional electric energy metering circuit is connect this outside precision voltage sources, and by a common mode voltage ground connection.
9. single-phase multifunctional electric energy metering circuit as claimed in claim 7, it is characterized in that: under this unbalance of system calibration mode, this automatic calibration module is the outside input pin short circuit of this this single-phase multifunctional electric energy metering circuit, and by a common mode voltage ground connection.
10. single-phase multifunctional electric energy metering circuit as claimed in claim 9, it is characterized in that: after the Hi-pass filter of three passages, the value of this DC maladjustment calibration register is revised the output of this Hi-pass filter by a totalizer respectively.
11. single-phase multifunctional electric energy metering circuit as claimed in claim 8, it is characterized in that: the result after the value of this DC current gain calibration register is calibrated DC maladjustment by a multiplier respectively revises, with this first current sampling data, this second current sampling data and this voltage sample data that needing to obtain.
12. single-phase multifunctional electric energy metering circuit as claimed in claim 9 is characterized in that: after the extraction of square root circuit, the value of this interchange mistuning calibration function register is revised the output of this extraction of square root circuit by a totalizer respectively.
13. single-phase multifunctional electric energy metering circuit as claimed in claim 1, it is characterized in that: this single-phase multifunctional electric energy metering circuit comprises a digital interface unit, this digital interface unit be used for and main control MCU between special delivery calibration parameter and metering result, it can be I2C, SPI, UART or single-wire communication bus.
14. the automatic calibrating method of an ammeter is applied to an intelligent electric meter system that comprises single-phase multifunctional electric energy metering circuit, comprises the steps: at least
Carry out before the calibration procedure, make this single-phase multifunctional electric energy metering circuit be in effective status, calibrate accordingly look-at-me and be reset;
The calibration reference signal of automatic calibration module is input to the analog input pin;
Main control MCU sends corresponding calibration command to the digital interface unit of metering circuit; And
This single-phase multifunctional electric energy metering circuit is finished internal calibration according to calibration command, the result is write corresponding calibration register and produce calibration to finish look-at-me indication calibration and finish.
15. the automatic calibrating method of ammeter as claimed in claim 14 is characterized in that: this calibration command is 8 order of the bit, and wherein every difference setting has been specified different calibration modes.
16. the automatic calibrating method of ammeter as claimed in claim 15 is characterized in that: this calibration mode comprises the DC maladjustment calibration mode, exchanges mistuning calibration function pattern, DC current gain calibration mode and ac gain calibration mode.
17. the automatic calibrating method of ammeter as claimed in claim 16 is characterized in that: exchange under the mistuning calibration function pattern the outside input pin short circuit ground connection of this single-phase multifunctional electric energy metering circuit with this at this DC maladjustment calibration mode
18. the automatic calibrating method of ammeter as claimed in claim 17, it is characterized in that: if the calibration mode of this calibration command is the DC maladjustment calibration mode, the mean value of the first current sampling data, the second current sampling data and voltage sample data in the nearest computation period is stored respectively into the DC maladjustment calibration register.
19. the automatic calibrating method of ammeter as claimed in claim 17, it is characterized in that: if the calibration mode of this calibration command stores respectively the mean value of the first current effective value, the second current effective value and voltage effective value in the nearest computation period into interchange mistuning calibration function register for exchanging the mistuning calibration function pattern.
20. the automatic calibrating method of ammeter as claimed in claim 16 is characterized in that: under this DC current gain calibration mode and this ac gain calibration mode, the outside input pin of this single-phase multifunctional electric energy metering circuit connects the direct current calibrating signal.
21. the automatic calibrating method of ammeter as claimed in claim 20, it is characterized in that: if the calibration mode of this calibration command is the DC current gain calibration mode, get inverse by the mean value of the transient voltage sampled value in the computation period and store the DC current gain calibration register into, then this mean value is adjusted, making corresponding instantaneous voltage sampled value is 1.
22. the automatic calibrating method of ammeter as claimed in claim 20, it is characterized in that: if the calibration mode of this calibration command is the ac gain calibration mode, getting inverse by the mean value of transient voltage sampled value in the computation period stores in the DC current gain calibration register, then this mean value is adjusted, making corresponding effective value value is 0.6.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110273013.2A CN102998525B (en) | 2011-09-15 | 2011-09-15 | Single-phase multifunctional electric energy metering circuit and ammeter automatic calibrating method thereof |
| CN201120345823XU CN202196119U (en) | 2011-09-15 | 2011-09-15 | Single-phase multifunctional electric energy metering circuit |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110273013.2A CN102998525B (en) | 2011-09-15 | 2011-09-15 | Single-phase multifunctional electric energy metering circuit and ammeter automatic calibrating method thereof |
| CN201120345823XU CN202196119U (en) | 2011-09-15 | 2011-09-15 | Single-phase multifunctional electric energy metering circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102998525A true CN102998525A (en) | 2013-03-27 |
| CN102998525B CN102998525B (en) | 2016-06-08 |
Family
ID=69147294
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201110273013.2A Active CN102998525B (en) | 2011-09-15 | 2011-09-15 | Single-phase multifunctional electric energy metering circuit and ammeter automatic calibrating method thereof |
| CN201120345823XU Expired - Lifetime CN202196119U (en) | 2011-09-15 | 2011-09-15 | Single-phase multifunctional electric energy metering circuit |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201120345823XU Expired - Lifetime CN202196119U (en) | 2011-09-15 | 2011-09-15 | Single-phase multifunctional electric energy metering circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (2) | CN102998525B (en) |
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103278679A (en) * | 2013-05-27 | 2013-09-04 | 上海贝岭股份有限公司 | Comparison circuit for electric energy measuring chip |
| CN103513211A (en) * | 2013-10-25 | 2014-01-15 | 国家电网公司 | Detecting device for alternating-current impedance tester |
| CN104407211A (en) * | 2014-12-06 | 2015-03-11 | 宁波迦南电子有限公司 | Power consumption metering device |
| CN104426548A (en) * | 2013-09-05 | 2015-03-18 | 上海海尔集成电路有限公司 | A/D (Analog/Digital) conversion sampling circuit and metering chip |
| CN106646331A (en) * | 2016-11-30 | 2017-05-10 | 芯海科技（深圳）股份有限公司 | Electricity meter metering chip, circuit and calibration method used for automatic calibration |
| CN106772202A (en) * | 2015-11-23 | 2017-05-31 | 云南电网有限责任公司电力科学研究院 | A kind of electric energy meter RS485 communication interface all-round property testing modules and method |
| CN107300640A (en) * | 2016-04-14 | 2017-10-27 | 上海贝岭股份有限公司 | Electric power meter |
| CN108614227A (en) * | 2015-12-18 | 2018-10-02 | 诺仪器（中国）有限公司 | The phase frequency calibration method and system of instrument with power measurement function |
| CN109061263A (en) * | 2018-08-31 | 2018-12-21 | 宁波三星智能电气有限公司 | A kind of electrical energy meter anti-theft electricity method |
| CN109100674A (en) * | 2018-05-28 | 2018-12-28 | 国网江西省电力有限公司电力科学研究院 | A kind of metering method based on distribution type electric energy, error detection method and device |
| CN110244118A (en) * | 2019-06-21 | 2019-09-17 | 和远智能科技股份有限公司 | A kind of multifunction electric meter |
| CN110704354A (en) * | 2019-09-16 | 2020-01-17 | 无锡江南计算技术研究所 | Common-mode noise suppression method for I2C communication bus and bus network |
| CN110988782A (en) * | 2019-12-19 | 2020-04-10 | 上海贝岭股份有限公司 | Calibration circuit and system, electric energy metering chip and metering device |
| CN112505612A (en) * | 2020-10-26 | 2021-03-16 | 青岛鼎信通讯股份有限公司 | Standard meter electric energy pulse output method applied to electric energy meter calibrating device |
| CN113541738A (en) * | 2021-06-18 | 2021-10-22 | 南京绿电智联科技有限公司 | Power line carrier communication chip with functions of active power and reactive power measurement |
| CN113627111A (en) * | 2021-07-15 | 2021-11-09 | 重庆倍来电新能源有限公司 | Tamper-proof trusted system for analog circuit |
| CN113820652A (en) * | 2021-11-18 | 2021-12-21 | 青岛鼎信通讯股份有限公司 | Sampling phase alignment and calibration method applied to standard electric energy meter |
| CN113866705A (en) * | 2021-08-27 | 2021-12-31 | 威胜集团有限公司 | Harmonic correction method and device, electric energy metering equipment and readable storage medium |
| CN116008655A (en) * | 2023-02-13 | 2023-04-25 | 山东省计量科学研究院 | Electric energy metering device for measuring bidirectional DC converter |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102998525B (en) * | 2011-09-15 | 2016-06-08 | 无锡华润矽科微电子有限公司 | Single-phase multifunctional electric energy metering circuit and ammeter automatic calibrating method thereof |
| CN103792424A (en) * | 2012-10-30 | 2014-05-14 | 水利部农村电气化研究所 | Electric energy meter having energy-saving function and application |
| CN103389411B (en) * | 2013-07-24 | 2016-08-31 | 江苏斯菲尔电气股份有限公司 | Multifunctional electric energy meter and energy data restoration methods thereof |
| CN103731148B (en) * | 2013-12-31 | 2017-04-26 | 上海英威腾工业技术有限公司 | Current sampling processing device and motor driver |
| CN105738692A (en) * | 2014-12-11 | 2016-07-06 | 苏州工业园区新宏博通讯科技有限公司 | Electric energy meter and debugging method thereof |
| CN109557496A (en) * | 2017-09-27 | 2019-04-02 | 宁波三星医疗电气股份有限公司 | A kind of correction method of electric energy meter |
| CN109557362A (en) * | 2018-11-24 | 2019-04-02 | 国网青海省电力公司西宁供电公司 | A kind of anti-electricity-theft monitoring method of distribution line and system |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1566968A (en) * | 2003-06-26 | 2005-01-19 | 上海华园微电子技术有限公司 | Pre-calibration electrical energy measuring chip |
| CN1605875A (en) * | 2003-10-06 | 2005-04-13 | 珠海炬力集成电路设计有限公司 | Multifunctional single-phase digital watthour meter |
| CN1725882A (en) * | 2004-07-19 | 2006-01-25 | 北京信威通信技术股份有限公司 | Real-time automatic calibrating method and system for radio base station array channel in SCDMA system |
| CN101536901A (en) * | 2008-03-21 | 2009-09-23 | 田小凡 | Blood pressure measuring circuit |
| CN101556322A (en) * | 2009-05-27 | 2009-10-14 | 深圳市科陆电子科技股份有限公司 | Auto-calibration method for single-phase electric energy meter on-site calibrator split-core type current mutual inductor |
| CN202196119U (en) * | 2011-09-15 | 2012-04-18 | 无锡华润矽科微电子有限公司 | Single-phase multifunctional electric energy metering circuit |
-
2011
- 2011-09-15 CN CN201110273013.2A patent/CN102998525B/en active Active
- 2011-09-15 CN CN201120345823XU patent/CN202196119U/en not_active Expired - Lifetime
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1566968A (en) * | 2003-06-26 | 2005-01-19 | 上海华园微电子技术有限公司 | Pre-calibration electrical energy measuring chip |
| CN1605875A (en) * | 2003-10-06 | 2005-04-13 | 珠海炬力集成电路设计有限公司 | Multifunctional single-phase digital watthour meter |
| CN1725882A (en) * | 2004-07-19 | 2006-01-25 | 北京信威通信技术股份有限公司 | Real-time automatic calibrating method and system for radio base station array channel in SCDMA system |
| CN101536901A (en) * | 2008-03-21 | 2009-09-23 | 田小凡 | Blood pressure measuring circuit |
| CN101556322A (en) * | 2009-05-27 | 2009-10-14 | 深圳市科陆电子科技股份有限公司 | Auto-calibration method for single-phase electric energy meter on-site calibrator split-core type current mutual inductor |
| CN202196119U (en) * | 2011-09-15 | 2012-04-18 | 无锡华润矽科微电子有限公司 | Single-phase multifunctional electric energy metering circuit |
Cited By (28)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103278679A (en) * | 2013-05-27 | 2013-09-04 | 上海贝岭股份有限公司 | Comparison circuit for electric energy measuring chip |
| CN104426548A (en) * | 2013-09-05 | 2015-03-18 | 上海海尔集成电路有限公司 | A/D (Analog/Digital) conversion sampling circuit and metering chip |
| CN104426548B (en) * | 2013-09-05 | 2017-07-28 | 上海东软载波微电子有限公司 | A kind of analog-to-digital conversion sample circuit and computation chip |
| CN103513211B (en) * | 2013-10-25 | 2016-03-02 | 国家电网公司 | Ac impedance measurement measuring device |
| CN103513211A (en) * | 2013-10-25 | 2014-01-15 | 国家电网公司 | Detecting device for alternating-current impedance tester |
| CN104407211B (en) * | 2014-12-06 | 2017-02-08 | 宁波迦南智能电气股份有限公司 | Power consumption metering device |
| CN104407211A (en) * | 2014-12-06 | 2015-03-11 | 宁波迦南电子有限公司 | Power consumption metering device |
| CN106772202B (en) * | 2015-11-23 | 2023-08-29 | 云南电网有限责任公司电力科学研究院 | Electric energy meter RS485 communication interface comprehensive performance testing module and method |
| CN106772202A (en) * | 2015-11-23 | 2017-05-31 | 云南电网有限责任公司电力科学研究院 | A kind of electric energy meter RS485 communication interface all-round property testing modules and method |
| CN108614227A (en) * | 2015-12-18 | 2018-10-02 | 诺仪器（中国）有限公司 | The phase frequency calibration method and system of instrument with power measurement function |
| CN108614227B (en) * | 2015-12-18 | 2020-09-08 | 一诺仪器（中国）有限公司 | Phase frequency calibration method and system of instrument with power measurement function |
| CN107300640A (en) * | 2016-04-14 | 2017-10-27 | 上海贝岭股份有限公司 | Electric power meter |
| CN106646331A (en) * | 2016-11-30 | 2017-05-10 | 芯海科技（深圳）股份有限公司 | Electricity meter metering chip, circuit and calibration method used for automatic calibration |
| CN109100674A (en) * | 2018-05-28 | 2018-12-28 | 国网江西省电力有限公司电力科学研究院 | A kind of metering method based on distribution type electric energy, error detection method and device |
| CN109100674B (en) * | 2018-05-28 | 2020-08-07 | 国网江西省电力有限公司电力科学研究院 | Metering method based on distributed electric energy, error detection method and device |
| CN109061263A (en) * | 2018-08-31 | 2018-12-21 | 宁波三星智能电气有限公司 | A kind of electrical energy meter anti-theft electricity method |
| CN110244118A (en) * | 2019-06-21 | 2019-09-17 | 和远智能科技股份有限公司 | A kind of multifunction electric meter |
| CN110704354A (en) * | 2019-09-16 | 2020-01-17 | 无锡江南计算技术研究所 | Common-mode noise suppression method for I2C communication bus and bus network |
| CN110704354B (en) * | 2019-09-16 | 2021-03-26 | 无锡江南计算技术研究所 | Common-mode noise suppression method for I2C communication bus and bus network |
| CN110988782A (en) * | 2019-12-19 | 2020-04-10 | 上海贝岭股份有限公司 | Calibration circuit and system, electric energy metering chip and metering device |
| CN112505612A (en) * | 2020-10-26 | 2021-03-16 | 青岛鼎信通讯股份有限公司 | Standard meter electric energy pulse output method applied to electric energy meter calibrating device |
| CN113541738A (en) * | 2021-06-18 | 2021-10-22 | 南京绿电智联科技有限公司 | Power line carrier communication chip with functions of active power and reactive power measurement |
| CN113541738B (en) * | 2021-06-18 | 2023-12-29 | 北方信通智能科技(南京)有限公司 | Power line carrier communication chip with active and reactive power metering functions |
| CN113627111A (en) * | 2021-07-15 | 2021-11-09 | 重庆倍来电新能源有限公司 | Tamper-proof trusted system for analog circuit |
| CN113627111B (en) * | 2021-07-15 | 2024-05-07 | 重庆倍来电新能源有限公司 | Tamper-proof trusted system for analog circuit |
| CN113866705A (en) * | 2021-08-27 | 2021-12-31 | 威胜集团有限公司 | Harmonic correction method and device, electric energy metering equipment and readable storage medium |
| CN113820652A (en) * | 2021-11-18 | 2021-12-21 | 青岛鼎信通讯股份有限公司 | Sampling phase alignment and calibration method applied to standard electric energy meter |
| CN116008655A (en) * | 2023-02-13 | 2023-04-25 | 山东省计量科学研究院 | Electric energy metering device for measuring bidirectional DC converter |
Also Published As
| Publication number | Publication date |
|---|---|
| CN202196119U (en) | 2012-04-18 |
| CN102998525B (en) | 2016-06-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN202196119U (en) | Single-phase multifunctional electric energy metering circuit | |
| CN104583784B (en) | The system and method for Input Power ＆ Current measurement | |
| CN106610450B (en) | A kind of single-phase electric energy metering chip | |
| US8165835B1 (en) | Complex wavelet filter based power measurement and calibration system | |
| JP4727514B2 (en) | Electricity meter | |
| CN102253358A (en) | Method for correcting electric energy meter by using correction system, and correction system | |
| CN110988782B (en) | Calibration circuit and system, electric energy metering chip and metering device | |
| CN203606434U (en) | Impedance measurement circuit | |
| CN105306056A (en) | Scale factor temperature compensating method of current frequency conversion circuit | |
| CN104849523A (en) | Single-phase watt-hour meter temperature compensation method | |
| CN105446409B (en) | Method for calibrating power supply and tuning power supply unit | |
| CN103424728A (en) | Method for performing single point correction on electric energy meter gain errors and phase errors | |
| KR100537018B1 (en) | System and Method for Frequency Compensation in an Energy Meter | |
| CN112513650A (en) | Current sensor configuration and calibration | |
| CN104020437A (en) | Electric energy meter correction method | |
| CN102565751A (en) | Device for developing programmable single-phase electric energy metering chip | |
| GB2408808A (en) | Electric power meter with phase shift compensation | |
| CN103575976B (en) | A kind of pure 90 degree of phase shift reactive power measuring methods | |
| CN102854381B (en) | Error compensation method of active powers and reactive powers | |
| CN112444671A (en) | Electric energy metering method and device of electric energy meter based on instantaneous power and storage medium | |
| KR101172742B1 (en) | Error compensation method for watt-hour meter | |
| CN101329215A (en) | Output measuring circuit and measuring method of capacitance differential pressure transducer | |
| CN109782057B (en) | Circuit and method for measuring input active power of single-phase power supply of variable-frequency household appliance | |
| CN115639400A (en) | High-precision alternating current electric energy metering method | |
| CN202281803U (en) | Pre-calibrated electric energy metering circuit |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CP03 | Change of name, title or address | ||
| CP03 | Change of name, title or address |
Address after: 214135 -6, Linghu Avenue, Wuxi Taihu international science and Technology Park, Wuxi, Jiangsu, China, 180 Patentee after: China Resources micro integrated circuit (Wuxi) Co., Ltd Address before: No.180-22, Linghu Avenue, Wuxi, Jiangsu 214000 Patentee before: WUXI CHINA RESOURCES SEMICO Co.,Ltd. |