CN103499803B - A kind of method improving precision of built-in real-time clock of electric energy meter MCU - Google Patents

A kind of method improving precision of built-in real-time clock of electric energy meter MCU Download PDF

Info

Publication number
CN103499803B
CN103499803B CN201310408138.0A CN201310408138A CN103499803B CN 103499803 B CN103499803 B CN 103499803B CN 201310408138 A CN201310408138 A CN 201310408138A CN 103499803 B CN103499803 B CN 103499803B
Authority
CN
China
Prior art keywords
temperature
mcu
analog switch
electric energy
crystal oscillator
Prior art date
Application number
CN201310408138.0A
Other languages
Chinese (zh)
Other versions
CN103499803A (en
Inventor
潘建华
郎干勇
李香
朱世林
徐振伟
吴静
王应娆
Original Assignee
扬州万泰电子科技有限公司
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 扬州万泰电子科技有限公司 filed Critical 扬州万泰电子科技有限公司
Priority to CN201310408138.0A priority Critical patent/CN103499803B/en
Publication of CN103499803A publication Critical patent/CN103499803A/en
Application granted granted Critical
Publication of CN103499803B publication Critical patent/CN103499803B/en

Links

Abstract

A kind of method improving precision of built-in real-time clock of electric energy meter MCU.Based on actual crystal oscillator frequency, and then fine compensation can be realized.Electric energy meter comprises MCU, crystal oscillator and Power Management Unit; Comprise the following steps: compensation rate calculates and corrects clock; Described compensation rate calculates is undertaken by following flow process: 1), measure actual crystal oscillator frequency departure at different temperatures; 2), draw temperature-frequency deviation curve sketch, and find out transition temperature T 0; 3), respectively to T 0the frequency departure that both sides record carries out curve fitting, draw corresponding buckling constant, 4), according to flow process 3) function, form a temperature-frequency deviation function table, according to actual environment temperature, namely obtain the frequency deviation value under Current Temperatures by described temperature-frequency deviation function table, as at actual environment temperature to the compensation rate that clock corrects.The present invention according to the error of actual crystal oscillator, can draw accurate offset, and then improves clock accuracy.

Description

A kind of method improving precision of built-in real-time clock of electric energy meter MCU
Technical field
The present invention relates to and a kind of improve built-in real-time clock of electric energy meter MCU RTC(Real-Time Clock) method of precision.
Background technology
Intelligent electric energy meter, as the measuring products of electric energy metrical and charge calculation, requires that product has stable accurate metering performance, ensures electricity consumption, the interests of power supply both sides are without prejudice.Current intelligent electric energy meter generally all has timesharing, multi-rate electric energy meter, more and more higher to the requirement of time degree of accuracy, and error of time of day produced problem is also more outstanding, all bring forward the overproof problem of error of time of day at the 2nd article " components and parts link " and Sub_clause 11 " design, fabrication " in the rectification notice that State Grid Corporation of China sends electric energy meter supplier on August 20th, 2013, require that emphasis is rectified and improved.According to the demand of technical standard of the intelligent electric energy meter of State Grid Corporation of China, the error of time of day of electric energy meter is necessary≤1s/d.The real-time clock of general employing has following 3 kinds: (1) soft clock.Due to the instability of crystal oscillator, the requirement of soft clock to crystal oscillator quality is high, for cost consideration, and the crystal oscillator that electric energy meter product can not adopt price high.(2) hardware clock.Hardware clock is subject to the impact of crystal oscillator degree of stability equally, and as RX-8025 chip conventional in early days, owing to not having temperature compensation function, thus clock accuracy is not high.RX-8025T afterwards adds temperature compensation function, and clock accuracy is higher, and clock stability is good, but cost is higher, and volume procurement valency is 8 yuan/only left and right, serious in short supply especially after Japanese violent earthquake in 2011.(3) mixing method, the i.e. built-in RTC of MCU.Because cost is lower, correct by software to RTC error simultaneously, adopt the built-in RTC of MCU to become the preferred option of electric energy meter design at present, the clock accuracy how improving built-in RTC just seems abnormal important.
Chinese patent CN102176112A proposes the method for the accurate timing of a kind of MCU built-in RTC real-time clock; The master thesis " research of self calibration real-time clock RTC and design " of Deng Qianzhong although in be the bearing calibration proposed for hardware clock design, but principle is the same with the method that Chinese patent CN102176112A proposes, all regard crystal oscillator frequency as para-curve that an axis of symmetry is parallel to Y-axis with the deviation of temperature, as shown in Figure 6, this is also the crystal oscillation frequency error model generally adopted at present, but have certain discrepancy with actual crystal oscillation frequency error, the precision of thus calibrating also can be under some influence.Record in this paper " the design have employed the scheme that built-in temperature sensor is combined with traditional RTC; obtain temperature information on sheet; and calibrate the digital calibrating method of division chain; and there is the problem of drift in the crystal oscillator frequency efficiently solving real-time clock, can realize the calibration of the accurate frequency of standard and nonstandard with temperature." but compensation mathematical model in the document have employed typical crystal temperature-precision curve map (in this article shown in Fig. 3-2, namely shown in Fig. 6 of the present invention).Owing to there being certain difference (actual crystal oscillator curve as shown in Figure 1) between actual crystal oscillator curve and typical crystal temperature-precision curve, final compensation rate will being caused so accurately not calibrate frequency, finally cause timing still to there will be error.
Summary of the invention
The present invention is directed to above problem, provide a kind of based on actual crystal oscillator frequency, and then the method for raising precision of built-in real-time clock of electric energy meter MCU of fine compensation can be realized.
Technical scheme of the present invention is: described electric energy meter comprises MCU, crystal oscillator and Power Management Unit, and described Power Management Unit connects battery and stabilized voltage supply by feed circuit;
Comprise the following steps: compensation rate calculates and corrects clock;
Described compensation rate calculates is undertaken by following flow process:
1) actual crystal oscillator frequency departure at different temperatures, is measured;
2), draw temperature-frequency deviation curve sketch, and find out transition temperature T 0;
3), respectively to T 0the frequency departure that both sides record carries out curve fitting, and draws corresponding buckling constant,
3.1), T<T is worked as 0time, the buckling constant K of temperature and frequency deviation function is simulated according to measured value 1value,
3.2), T>T is worked as 0time, the buckling constant K of temperature and frequency deviation function is simulated according to measured value 2value,
3.3), T=T is worked as 0, Δ f equals Δ f 0,
Must as minor function:
&Delta;f = - k 1 ( T - T 0 ) 2 + &Delta; f 0 T > T 0 &Delta; f 0 T = T 0 - k 2 ( T - T 0 ) 2 + &Delta; f 0 T < T 0
Wherein Δ f 0=f t0-32768Hz, f t0for the actual frequency under transition temperature;
4), according to flow process 3) function, form a temperature-frequency deviation function table, according to actual environment temperature, namely obtain the frequency deviation value under Current Temperatures by described temperature-frequency deviation function table, as at actual environment temperature to the compensation rate that clock corrects.
Anti-battery passivation circuit is provided with in described feed circuit; Described anti-battery passivation circuit comprises resistance R1, analog switch K1, described resistance R1 one end is connected with described anode, the described resistance R1 other end is connected with described analog switch K1 one end, the described analog switch K1 other end connects described battery cathode, described analog switch K1 is in normally open, and the control end of described analog switch K1 receives an I/O mouth control signal of described MCU to control break-make.
Described resistance R1 value is 1-1.8K Ω.
Set up defences in described MCU passivation control module, described anti-passivation control module controls the break-make of described analog switch K1 by the following method,
1), in 15-30 days, have a power failure, the I/O mouth that described MCU controls described analog switch K1 sends high level, and make described analog switch K1 conducting, then battery starts of short duration electric discharge, and ON time is 5-15 minute; Then an I/O mouth of described MCU sends low level, and described analog switch K1 is disconnected, then battery discharge terminates;
2), in 15-30 days, have a power failure, the I/O mouth that described MCU controls described analog switch K1 sends low level always, makes to state analog switch K1 and is in off-state always.
The operating voltage of crystal oscillator is 3.3V.
The present invention tries to achieve actual crystal oscillator frequency-temperature curve, and according to the parabolical present situation of this curve anon-normal; Then, propose innovatively and this curve is carried out segmentation, the frequency deviation of each section is calculated respectively; Finally, then the technical scheme compensated.Overcome after compensating in prior art, it is larger that what clock timing precision still existed depart from transition temperature, the problem that deviation value is larger.In other words, as according to the traditional compensation technique in this area, adopt typical crystal temperature-precision curve map, owing to will look after the temperature compensation of transition temperature both sides, so when departing from transition temperature and being larger, the compensation precision of curve far-end is poorer.As shown in Figure 5, the clock accuracy adopting the electric energy meter of technical solution of the present invention to embody is the time deviation curve 1 after compensation of the present invention, and approximate straight straight line, at each temperature, all can reflect correct duration to greatest extent.And after adopting in prior art and compensating based on typical curve, can be formed prior art compensate after time deviation curve 1, prior art compensate after time deviation curve 23, prior art compensate after time deviation curve 34, prior art compensate after time deviation curve 45 in four kinds of array configurations (2+3,2+4,5+3,5+4).The present invention according to the error of actual crystal oscillator, can draw accurate offset, and then improves clock accuracy.
Accompanying drawing explanation
Fig. 1 is temperature-frequency deviation curve figure of the present invention,
Fig. 2 is RTC digital calibration schematic diagram of the present invention,
Fig. 3 is the wiring diagram of feed circuit of the present invention,
Fig. 4 is the functional structure chart of the MCU of electric energy meter of the present invention,
Fig. 5 is the comparison diagram of of the present invention obtained RTC compensation precision and traditional RTC compensation precision,
Fig. 6 is the typical crystal temperature-precision curve map of prior art;
In figure, 1 is the time deviation curve after compensation of the present invention, 2 is the time deviation curves one after prior art compensates, 3 be prior art compensate after time deviation curve two, 4 be prior art compensate after time deviation curve three, 5 be prior art compensate after time deviation curve four.
Embodiment
The present invention is as Figure 1-4: described electric energy meter comprises MCU, crystal oscillator and Power Management Unit, and described Power Management Unit connects battery and stabilized voltage supply by feed circuit;
Comprise the following steps: compensation rate calculates and corrects clock;
Described compensation rate calculates is undertaken by following flow process:
1) actual crystal oscillator frequency departure at different temperatures, is measured;
2), draw temperature-frequency deviation curve sketch, and find out transition temperature T 0;
3), respectively to T 0the frequency departure that both sides record carries out curve fitting, and draws corresponding buckling constant,
3.1), T<T is worked as 0time, the buckling constant K of temperature and frequency deviation function is simulated according to measured value 1value,
3.2), T>T is worked as 0time, the buckling constant K of temperature and frequency deviation function is simulated according to measured value 2value,
3.3), T=T is worked as 0, Δ f equals Δ f 0,
Must as minor function:
&Delta;f = - k 1 ( T - T 0 ) 2 + &Delta; f 0 T > T 0 &Delta; f 0 T = T 0 - k 2 ( T - T 0 ) 2 + &Delta; f 0 T < T 0
Wherein Δ f 0=f t0-32768Hz, f t0for the actual frequency under transition temperature;
4), according to flow process 3) function, form a temperature-frequency deviation function table, according to actual environment temperature, namely the frequency deviation value under Current Temperatures is obtained by described temperature-frequency deviation function table, the value of amendment correcting register, and then by calibration circuit, frequency dividing circuit is compensated, as at actual environment temperature to the compensation rate that clock corrects.
Anti-battery passivation circuit is provided with in described feed circuit; Described anti-battery passivation circuit comprises resistance R1, analog switch K1, described resistance R1 one end is connected with described anode, the described resistance R1 other end is connected with described analog switch K1 one end, the described analog switch K1 other end connects described battery cathode, described analog switch K1 is in normally open, and the control end of described analog switch K1 receives an I/O mouth control signal of described MCU to control break-make.
Described resistance R1 value is 1-1.8K Ω.
Set up defences in described MCU passivation control module, described anti-passivation control module controls the break-make of described analog switch K1 by the following method,
1), in 15-30 days, have a power failure, the I/O mouth that described MCU controls described analog switch K1 sends high level, and make described analog switch K1 conducting, then battery starts of short duration electric discharge, and ON time is 5-15 minute; Then an I/O mouth of described MCU sends low level, and described analog switch K1 is disconnected, then battery discharge terminates;
2), in 15-30 days, have a power failure, the I/O mouth that described MCU controls described analog switch K1 sends low level always, makes to state analog switch K1 and is in off-state (anti-battery passivation circuit does not work) always.
Because when normal work, electric energy meter lithium battery does not work, in the long-time not used time, battery can enter passive state and cause battery decompression, thus timing comparatively big error can be brought when powered battery, in the 2nd article " components and parts link ", propose battery passivation first in the rectification notice that State Grid Corporation of China sends electric energy meter supplier on August 20th, 2013 and cause battery decompression problem, require that emphasis is rectified and improved.The present invention adds anti-battery passivation circuit in electric energy meter design, and circuit as shown in Figure 3.In electric energy meter program operation process, (length of time is determined by the characteristic of battery) is closed by the I/O mouth output high level control single channel bidirectional analog switch K1 of MCU at set intervals, battery is resistance R1 and analog switch K1(model: the M74VHC1GT66DFT1G of 1.2K by resistance) electric discharge, enter passive state to prevent battery.In battery discharge procedure, the electric current that battery consumes is 3mA.Discharge period should be not long, in case consume too much battery electric quantity.After electric discharge terminates, this I/O mouth sets to 0 and makes analog switch be in off-state by program again, and battery no longer discharges.By this function, the error of time of day because battery passivation brings can be avoided to greatest extent.
The operating voltage of crystal oscillator is 3.3V.
General electric energy meter slip-stick artist only can consider crystal oscillator wiring and chip power-consumption problem when designing, and can not consider the impact of power supply on clock accuracy.The applicant finds on stream, if the crystal oscillator that low-voltage (3.3V) should be adopted to power adopts High Voltage Power Supply (5V), not only Conducted Radio Frequency radiation amplitude can be brought greatly to become large because crystal oscillator wave of oscillation amplitude becomes, and clock accuracy can be made to reduce.The present invention analyzes the Influencing Mechanism of power supply to clock accuracy, and proposes a kind of choosing method of chip operation power supply.
Clock accuracy reduces concrete reason and is analyzed as follows: intelligent electric energy meter, all with 3.6V lithium battery, when having a power failure by lithium battery power supply, being powered to maintain crystal oscillator clock to electric energy meter, being guaranteed that timing is continuous.If crystal oscillator working power is 5V during normal work, power when transferring lithium battery 3.6V to after power failure, crystal oscillator frequency is by change 1 ~ 2ppm, i.e. 0.1728s/d.The corrected value that just temperature variation is corresponding that correcting register due to RTC stores, therefore mains supply and powered battery switch and will cause timing error.Therefore, during design, crystal oscillator operating voltage is preferably 3.3V, so that consistent with battery power voltage (3.6V is 3.3V substantially after switching diode by powered battery).V9811 adopts 3.3V or 5V single power supply, built-in 3.3V mu balanced circuit is used as the mimic channel operating voltage such as crystal oscillator, 3.3V voltage ripple is very little, therefore when power consumption meets the demands, adopt 5V Power supply, the 3.3V power supply produced by the voltage stabilizing of 5V power source internal supplies crystal oscillator, and crystal oscillator frequency degree of stability comparatively will be got well with the outside 3.3V Power supply that ripple is relatively large.
The present invention is further illustrated below in conjunction with specific embodiment:
The V9811 integrated chip that electric energy meter master chip MCU adopts Hangzhou Vango Science & Technology Co., Ltd. to research and develop, V9811 functional block diagram as shown in Figure 4.V9811 is the single-phase measurement SoC chip of a Low Power High Performance, the functional modules such as MCU, RTC, WDT, Flash, RAM and LCD driving of integrated simulation front end, electric energy metering module, enhancement mode 8052 kernel, 64-LQFP encapsulates, for single-phase multifunctional ammeter provides single chip solution.V9811 adopts 3.3V or 5V single power supply, and integrated start-oscillation circuit and PLL, sheet only needs a 32768Hz crystal oscillator outward.The built-in high-performance RTC of V9811, support temperature compensates, and every 30s corrects once, and in total temperature working range, error is within 5ppm.Embedded has temperature measuring circuit, and measuring accuracy is up to ± 1 DEG C.
Due to the impact of temperature and discreteness, the frequency of 32768Hz crystal oscillator external when chip normally runs has different actual oscillation frequency in the different time.By temperature sensor measurement Current Temperatures, draw the offset of RTC under Current Temperatures environment according to temperature curve, correcting register can correct RTC timing, reduce this species diversity on finally actual walk time the impact that brings.
The crystal oscillator frequency of the actual measurement that V9811 databook provides and temperature curve (this handbook Figure 17-8), when crystal oscillator temperature is obviously greater than crystal oscillator temperature higher than curvature during transition temperature lower than curvature during transition temperature, but still it is treated as para-curve process in databook.
To the crystal oscillator of actual purchase, the method for testing that we provide according to V9811 databook, obtains the curve map of Fig. 1, when crystal oscillator temperature is significantly less than crystal oscillator temperature higher than curvature during transition temperature lower than curvature during transition temperature.Visible, crystal oscillator frequency and temperature curve are not the para-curve that a desirable axis of symmetry is parallel to Y-axis.Physical relationship curve, according to the supplier of buying crystal oscillator and batch relevant, therefore generally not being changed supplier, all must be re-started temperature compensation correction when changing supplier and different batches purchases after determining crystal oscillator supplier.That is, to different batches, the crystal oscillator of different supplier, all should obtain actual crystal oscillator frequency and temperature curve, as basis of the present invention.
Through multiple batches of detection, find the curve shape deviation outwardness of crystal oscillator of different batches, supplier, not only there is the situation of downward shift, i.e. constant term Δ f 0there is deviation; Also there is T odeviation and curvature deviation.Therefore, the present invention proposes with transition temperature T ofor boundary, by transition temperature T othe frequency-temperature curve on both sides approaches with the parabolic function that different curve opens rate respectively.
The method substantially increases clock of power meter precision.
To detect through State Grid Metering Center according to the electric energy meter of technical solution of the present invention trial-production and show, error of time of day is minimum, and environment temperature is that the impact of error is minimum on diary.Specific experiment situation is as follows:
1, error of time of day test:
1), technical conditions: Q/GDW1828-20134.5.6.a) bar
2), technical conditions: Q/GDW1828-20135.1.6.1 bar
3), testing equipment: ST9020 type unidirectional electric energy table calibrating dress
4), test findings:
Permissible error Test findings
+/-1s/d 0.00
5), conclusion (of pressure testing): meet
2, environment temperature is tested the impact of error of time of day:
1), technical conditions: Q/GDW1828-20134.5.6.b) bar
2), technical conditions: Q/GDW1828-20135.1.6.2 bar
3), testing equipment: ST9020 type unidirectional electric energy table calibrating installation, SDJ/W440 type walk-in type high-and-low temperature humid heat test box
4), test findings:
5), conclusion (of pressure testing): meet.

Claims (4)

1. one kind is improved the method for precision of built-in real-time clock of electric energy meter MCU, described electric energy meter comprises MCU, crystal oscillator and Power Management Unit, described Power Management Unit connects battery and stabilized voltage supply by feed circuit, comprise the following steps: compensation rate calculates and corrects clock, described compensation rate calculates is undertaken by following flow process:
1) actual crystal oscillator frequency departure at different temperatures, is measured;
2), draw temperature-frequency deviation curve sketch, and find out transition temperature T 0;
3), respectively to T 0the frequency departure that both sides record carries out curve fitting, and draws corresponding buckling constant,
3.1), T<T is worked as 0time, the buckling constant K of temperature and frequency deviation function is simulated according to measured value 1value,
3.2), T>T is worked as 0time, the buckling constant K of temperature and frequency deviation function is simulated according to measured value 2value,
3.3), T=T is worked as 0, Δ f equals Δ f 0,
Must as minor function:
&Delta; f = - k 1 ( T - T 0 ) 2 + &Delta;f 0 T > T 0 &Delta;f 0 T = T 0 - k 2 ( T - T 0 ) 2 + &Delta;f 0 T < T 0
Wherein Δ f 0=f t0-32768Hz, f t0for the actual frequency under transition temperature;
4), according to flow process 3) function, form a temperature-frequency deviation function table, according to actual environment temperature, namely obtain the frequency deviation value under Current Temperatures by described temperature-frequency deviation function table, as at actual environment temperature to the compensation rate that clock corrects;
It is characterized in that, in described feed circuit, be provided with anti-battery passivation circuit; Described anti-battery passivation circuit comprises resistance R1, analog switch K1, described resistance R1 one end is connected with described anode, the described resistance R1 other end is connected with described analog switch K1 one end, the described analog switch K1 other end connects described battery cathode, described analog switch K1 is in normally open, and the control end of described analog switch K1 receives an I/O mouth control signal of described MCU to control break-make.
2. a kind of method improving precision of built-in real-time clock of electric energy meter MCU according to claim 1, is characterized in that, described resistance R1 value is 1-1.8K Ω.
3. a kind of method improving precision of built-in real-time clock of electric energy meter MCU according to claim 1, is characterized in that, passivation control module of setting up defences in described MCU, and described anti-passivation control module controls the break-make of described analog switch K1 by the following method,
1), in 15-30 days, have a power failure, the I/O mouth that described MCU controls described analog switch K1 sends high level, and make described analog switch K1 conducting, then battery starts of short duration electric discharge, and ON time is 5-15 minute; Then an I/O mouth of described MCU sends low level, and described analog switch K1 is disconnected, then battery discharge terminates;
2), in 15-30 days, have a power failure, the I/O mouth that described MCU controls described analog switch K1 sends low level always, makes described analog switch K1 be in off-state always.
4. a kind of method improving precision of built-in real-time clock of electric energy meter MCU according to claim 1, is characterized in that, the operating voltage of crystal oscillator is 3.3V.
CN201310408138.0A 2013-09-09 2013-09-09 A kind of method improving precision of built-in real-time clock of electric energy meter MCU CN103499803B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201310408138.0A CN103499803B (en) 2013-09-09 2013-09-09 A kind of method improving precision of built-in real-time clock of electric energy meter MCU

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201310408138.0A CN103499803B (en) 2013-09-09 2013-09-09 A kind of method improving precision of built-in real-time clock of electric energy meter MCU

Publications (2)

Publication Number Publication Date
CN103499803A CN103499803A (en) 2014-01-08
CN103499803B true CN103499803B (en) 2015-09-09

Family

ID=49865026

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201310408138.0A CN103499803B (en) 2013-09-09 2013-09-09 A kind of method improving precision of built-in real-time clock of electric energy meter MCU

Country Status (1)

Country Link
CN (1) CN103499803B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106569544A (en) * 2015-10-10 2017-04-19 上海东软载波微电子有限公司 Real time clock chip, and clock calibration method and apparatus

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104007652A (en) * 2014-06-16 2014-08-27 管存忠 Method for reducing electronic timing error
CN104714404A (en) * 2014-12-30 2015-06-17 华立仪表集团股份有限公司 Method for improving clock precision in electric energy meter
CN104635196B (en) * 2015-02-10 2017-07-07 武汉阿迪克电子股份有限公司 Take the real-time clock synchronization error correction method of control intelligent electric energy meter
CN104682952B (en) * 2015-02-11 2018-05-15 杭州海兴电力科技股份有限公司 A kind of clock compensation method suitable for SOC schemes
CN106054580B (en) * 2016-07-04 2018-04-06 华立科技股份有限公司 The second signal calibration method of clock chip
CN106054579B (en) * 2016-07-04 2018-02-16 华立科技股份有限公司 The second signal software calibration method of clock chip
CN106505996B (en) * 2016-10-12 2019-02-12 河海大学 A kind of RTC chip high-precision frequency bias compensation method of combination variable capacitance
CN107272821B (en) * 2017-06-07 2020-02-21 上海东软载波微电子有限公司 Real-time clock calibration method and device, storage medium and electronic equipment
CN107884608B (en) * 2017-11-02 2020-10-23 钜泉光电科技(上海)股份有限公司 Electric energy meter control system and clock correction method
CN107907850B (en) * 2017-11-02 2020-11-17 华立科技股份有限公司 Three-phase electric energy meter clock calibration and error calibration method
CN108011631A (en) * 2017-12-19 2018-05-08 建荣半导体(深圳)有限公司 Work clock generation method, clock source and chip

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5325048A (en) * 1992-04-14 1994-06-28 Digital Kwh Inc. Method and apparatus for calibrating a digital electric engergy consumption meter
CN101303401A (en) * 2008-07-01 2008-11-12 长沙威胜电子有限公司 RTC regulating apparatus of electrical energy meter and RTC automatic compensation correcting method
CN201212907Y (en) * 2008-07-01 2009-03-25 长沙威胜电子有限公司 RTC calibration apparatus for electric energy meter
CN102435975A (en) * 2011-11-07 2012-05-02 中国电力科学研究院 Intelligent cost control electric energy meter and clock calibration method
CN202904000U (en) * 2012-10-26 2013-04-24 威胜集团有限公司 RTC clock verification apparatus for electric energy meters
CN103163369A (en) * 2011-12-19 2013-06-19 无锡华润矽科微电子有限公司 Electric energy measuring circuit structure capable of achieving function of pre-calibration of measurement accuracy and method thereof
CN103176400A (en) * 2013-01-14 2013-06-26 杭州海兴电力科技股份有限公司 Intelligent ammeter clock calibration method

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2911737B1 (en) * 2007-01-23 2009-03-27 Ulis Soc Par Actions Simplifie Method for scanning an analogue size, scanning device using the same, and electromagnetic radiation detector incorporating such a device

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5325048A (en) * 1992-04-14 1994-06-28 Digital Kwh Inc. Method and apparatus for calibrating a digital electric engergy consumption meter
CN101303401A (en) * 2008-07-01 2008-11-12 长沙威胜电子有限公司 RTC regulating apparatus of electrical energy meter and RTC automatic compensation correcting method
CN201212907Y (en) * 2008-07-01 2009-03-25 长沙威胜电子有限公司 RTC calibration apparatus for electric energy meter
CN102435975A (en) * 2011-11-07 2012-05-02 中国电力科学研究院 Intelligent cost control electric energy meter and clock calibration method
CN103163369A (en) * 2011-12-19 2013-06-19 无锡华润矽科微电子有限公司 Electric energy measuring circuit structure capable of achieving function of pre-calibration of measurement accuracy and method thereof
CN202904000U (en) * 2012-10-26 2013-04-24 威胜集团有限公司 RTC clock verification apparatus for electric energy meters
CN103176400A (en) * 2013-01-14 2013-06-26 杭州海兴电力科技股份有限公司 Intelligent ammeter clock calibration method

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106569544A (en) * 2015-10-10 2017-04-19 上海东软载波微电子有限公司 Real time clock chip, and clock calibration method and apparatus

Also Published As

Publication number Publication date
CN103499803A (en) 2014-01-08

Similar Documents

Publication Publication Date Title
Drake et al. A distributed critical-path timing monitor for a 65nm high-performance microprocessor
CN202339381U (en) Harmonic electric energy metering system based on Nuttall self-convolution window weighed FFT (Fast Fourier Transform)
Calhoun et al. Modeling and sizing for minimum energy operation in subthreshold circuits
Gambhir et al. The future costs of OPV–A bottom-up model of material and manufacturing costs with uncertainty analysis
Aichhorn et al. A cost effective battery sizing strategy based on a detailed battery lifetime model and an economic energy management strategy
CN102338669B (en) Low voltage low power CMOS temperature sensor circuit
US20140244065A1 (en) Voltage stability monitoring in power systems
CN103018680B (en) Metering method and metering device of battery level and battery supply set
CN202818249U (en) RC oscillator apparatus and circuit
CN103885026B (en) Electric energy meter calibrating method
CN105445645B (en) A kind of numeric type observation circuit for being used to monitor integrated circuit NBTI aging effects
CN102272687A (en) System and method of determining maximum power point tracking for a solar power inverter
CN102253643B (en) High-precision time measuring circuit and method
CN103823189B (en) The computational methods of the residual capacity of power battery pack
CN102938220B (en) Method for correcting clock of automatic ship identifying terminal equipment
CN104880673A (en) Method for measuring battery electric quantity and mobile terminal
CN201887731U (en) Adjustable high-precision RC oscillating circuit
WO2014039817A2 (en) Low power clock source
CN102405678B (en) Method and apparatus for calibrating low frequency clock
TW201119240A (en) An integrated circuit frequency generator
US20140002147A1 (en) Clock correction circuit and clock correction method
CN102201787A (en) Constant-temperature piezoelectric oscillator and method of manufacturing the same
CN103873048B (en) On-chip RC oscillator with frequency self correction function and frequency self correction method
CN103454905B (en) A kind of method for synchronizing time
CN104849523B (en) The temperature compensation of single-phase electric energy meter

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
ASS Succession or assignment of patent right

Owner name: YANGZHOU WANTAI ELECTRONIC TECHNOLOGY CO., LTD.

Free format text: FORMER OWNER: YANGZHOU CITY WANTAI ELECTRIC FACTORY CO., LTD.

Effective date: 20150618

C41 Transfer of patent application or patent right or utility model
TA01 Transfer of patent application right

Effective date of registration: 20150618

Address after: 225003 No. 31 Zhuanghe Road, Yangzhou economic and Technological Development Zone, Jiangsu, China

Applicant after: YANGZHOU WANTAI ELECTRIC TECHNOLOGY CO., LTD.

Address before: 225000 No. 31 Zhuanghe Road, Yangzhou economic and Technological Development Zone, Jiangsu, China

Applicant before: Yangzhou Wantai Electrical Appliances Factory Co., Ltd.

C14 Grant of patent or utility model
GR01 Patent grant