CN102062810A - Detection circuit and method for zero crossing point of alternating current power supply - Google Patents
Detection circuit and method for zero crossing point of alternating current power supply Download PDFInfo
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- CN102062810A CN102062810A CN 201010586260 CN201010586260A CN102062810A CN 102062810 A CN102062810 A CN 102062810A CN 201010586260 CN201010586260 CN 201010586260 CN 201010586260 A CN201010586260 A CN 201010586260A CN 102062810 A CN102062810 A CN 102062810A
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Abstract
The invention discloses a detection circuit and method for a zero crossing point of an alternating current power supply. A half-wave shaping circuit is formed by a current limiting resistor and a light-emitting diode, a cathode of a protective diode is connected with the current limiting resistor, and the other end of the current limiting resistor is connected with an input end of the alternating current power supply; and a photistor collector is connected with a singlechip and a direct current power supply through another light-emitting diode. The singlechip firstly detects twice level trip interruption time t1 and t3 of a previous alternating current power supply positive half-wave, calculates a previous wave crest moment t2, then detects the twice level trip interruption time t4 and t6 of a next alternating current power supply positive half-wave and a wave crest time t5 at the time to obtain an alternating current power supply period, and outputs a control signal to control a thyristor to be accurately triggered with a next zero crossing point moment as a benchmark. The detection circuit and method for the zero crossing point of the alternating current power supply enhance the driving capacity of a voltage without other gate circuits, has no requirements on amplitude and frequency of the alternating current power supply and no limits on a working voltage of the light-emitting diode and can allow a voltage value of the alternating current power supply to fluctuate in a large range.
Description
Technical field
The present invention relates to a kind of testing circuit and detection method of AC power zero crossing, be applied to belong to the electrical engineering field in the controllable silicon phase-shift control circuit.
Background technology
Zero passage detection refers to that alternating voltage zero-crossing point is detected automatically, and then is reference point with the zero crossing, according to the conducting of phase shifting angle control electronic switch, is usually used in the output control device of controllable silicon as switching device.Since controllable silicon have only when the anode anticathode be that positive bias and control utmost point anticathode could conductings during also for positive bias, therefore, the accurate detection of AC power zero crossing becomes crucial unusually, because definite reference point that is directly determining synchronizing signal of its value.Can realize also that simultaneously the power electronic devices no-voltage opens the basic demand with zero-current switching, reduce the switching loss of device, guarantee that it is in the safety operation area.
The patent No. is 01114618.4 to disclose a kind of testing circuit of AC power synchronous signal, directly adopts AC power as signal source, utilizes the non-linear of diode and electronic switching device, detects the zero cross signal of AC power.This method is for more than the input voltage higher (as 220V), the zero crossing synchronous triggering signal just relatively accurately, when if input voltage is low below (as 10V), departing from of zero passage synchronous triggering signal is just big, this mainly is that the nonlinear characteristic that drives triode and light emitting diode determines, and driving circuit does not have realization photoelectricity truly to isolate, and a little less than the antijamming capability, reliability is relatively low.
The patent No. is 200510018270.6 to disclose and a kind ofly obtain the silicon control zero-cross synchronizing signal and trigger control method, also be directly to utilize AC power as signal source, utilize light transfer characteristic, the front and back of detecting trapezoidal wave signal after the shaping with single-chip microcomputer calculate the moment of zero crossing along the corresponding time.This method is done sine wave shaped near zero point, misoperation appears easily, the single-chip microcomputer signal Processing is brought than mistake, in addition, single-chip microcomputer must detect the negative edge of trapezoidal wave, just can obtain zero crossing constantly, this moment, zero crossing was a past tense constantly, can not satisfy the accurately requirement of triggering of zero crossing of some circuit.
Summary of the invention
The present invention overcomes the influence that the precision of silicon control zero-cross point synchronous triggering signal in the above-mentioned prior art is subjected to the input voltage height; and trigger pip causes the deficiency that misoperation can not accurately trigger easily; a kind of AC power zero-crossing detection circuit is provided; the height of this testing circuit and input voltage is irrelevant, and the impact of surge is avoided in protection controllable silicon and load thereof.The present invention also provides the detection method of this testing circuit, realizes that silicon control zero-cross point high-precise synchronization triggers.
The technical scheme that testing circuit of the present invention adopts is: current-limiting resistance R1 and light emitting diode D2 constitute the half-wave shaping circuit, protection diode D1 negative electrode links to each other with current-limiting resistance R1, anode connects simulation ground, and the other end of current-limiting resistance R1 connects the input end of AC power Ui; The emitter of phototriode T1 connects digitally, and its collector connects single-chip microprocessor MCU and links to each other with direct supply Vcc by another current-limiting resistance R2; At the positive half-wave of AC power Ui, light emitting diode D2 was luminous when AC power Ui voltage was higher than the operating voltage of light emitting diode D2, phototriode T1 conducting, and output voltage U o is by phototriode T1 ground connection, output low level; Light emitting diode D2 is not luminous when AC power Ui voltage is lower than the operating voltage of light emitting diode D2, and phototriode T1 ends, and output voltage U o meets DC voltage Vcc by current-limiting resistance R2, the output high level.
Detection method of the present invention adopts following steps: single-chip microcomputer detects preceding 1 AC power U earlier
iThe time t1 of 2 level saltus steps of positive half-wave and the value of t3 are calculated the preceding 1 time crest value of t2 constantly then, detect following 1 AC power U again
iThe value of positive half-wave 2 level bound-times t4 and t6 is calculated the value of crest time t5 at this moment, calculates the AC power cycle then
Value, calculate next zero crossing constantly
Value, last single-chip microcomputer keeps t1=t4, t2=t5, these 3 of t3=t6 be value constantly, for detect service next time, is reference point constantly with t7, according to the requirement output control signal of phase shifting angle, the control controllable silicon accurately triggers.
The beneficial effect that the present invention has is:
1, AC power is applied directly on the series circuit that current-limiting resistance and light emitting diode constitute,, the operating voltage of light emitting diode is not limited the amplitude and the equal no requirement (NR) of frequency of AC power; The magnitude of voltage of tolerable AC power fluctuates on a large scale, and applicability is strong.
2, do not require that hardware realization zero crossing detects, by the luminous of luminotron with extinguish, make the phototriode conducting with end, sine wave signal is shaped as square-wave signal, and it is luminous to allow that sine wave triggers light emitting diode at any time, and single-chip microcomputer detects the time on edge, square-wave signal front and back, mode with computed in software obtains the cycle of sine wave signal and the next zero crossing moment of AC power, degree of freedom is big, and utilization has improved the precision that detects zero point flexibly.
3, circuit is simple, does not want the driving force that other extra gate circuits come booster tension, the reliability height, and cost is lower, and is easy to maintenance.
Description of drawings
Fig. 1 is the schematic diagram of testing circuit of the present invention; Fig. 2 is the algorithm flow chart in the detection method of the present invention; Fig. 3 is the voltage oscillogram of the embodiment of the invention.
Embodiment
With reference to Fig. 1, constitute the half-wave shaping circuit by current-limiting resistance R1 and light emitting diode D2, the anode of protection diode D1 connects simulation ground, and its negative electrode links to each other with current-limiting resistance R1, and the other end of current-limiting resistance R1 connects AC power U
iInput end; The emitter of phototriode T1 connects digitally, and its collector links to each other with direct supply Vcc by another current-limiting resistance R2, and this collector output is through the output voltage U of shaping simultaneously
o, output voltage U
oBe connected to the input end of single-chip microprocessor MCU.Input, output signal realize Signal Spacing not altogether fully like this, improve the reliability of circuit.
At the positive half-wave of AC power Ui, as AC power U
iVoltage when being higher than the operating voltage of light emitting diode D2, light emitting diode D2 is luminous, phototriode T1 conducting, output voltage U
oBy phototriode T1 ground connection, output low level; As AC power U
iVoltage when being lower than the operating voltage of light emitting diode D2, light emitting diode D2 is not luminous, phototriode T1 ends, output voltage U
oMeet DC voltage Vcc by current-limiting resistance R2, the output high level.Single-chip microprocessor MCU detects the time of high-low level upset respectively, draws the cycle of sine wave signal and the moment of the next zero crossing of AC power by computed in software.
The step that single-chip microprocessor MCU detects is with reference to Fig. 2, and is specific as follows:
Step 302: single-chip microprocessor MCU at first detects the time t1 of 2 level saltus steps of preceding 1 AC power Ui positive half-wave and the value of t3;
Step 304: single-chip microprocessor MCU is calculated the preceding 1 time crest value of t2 constantly;
Step 306: single-chip microprocessor MCU detects following 1 AC power U again
iThe value of positive half-wave 2 level bound-times t4 and t6;
Step 308: single-chip microprocessor MCU is calculated the value of crest time t5 this moment;
Step 310: single-chip microprocessor MCU calculates the value of AC power period T 1;
Step 312: single-chip microprocessor MCU is calculated the next zero crossing value of t7 constantly;
Step 314: single-chip microprocessor MCU keeps t1=t4, t2=t5, and these 3 of t3=t6 are worth constantly, are the service that next time detects;
The program loop that above-mentioned single-chip microprocessor MCU detects is reciprocal, constantly estimate next zero crossing constantly, hence one can see that, and in time the amplitude of power supply changes, and also can detect zero crossing smoothly.
Below provide 1 embodiment of the present invention to further specify the present invention.
Embodiment
According to shown in Figure 1 circuit is connected earlier,, shown AC power U then with reference to the voltage waveform of Fig. 3
iTwo crests, AC power U
iThe place makes light emitting diode D2 conducting, output voltage U at the A point
oObtain low level, the time value that single-chip microprocessor MCU detects this moment is t1; AC power U
iReduce at B point place magnitude of voltage, light emitting diode D2 is not luminous, output voltage U
oObtain high level, the time value that single-chip microprocessor MCU detects this moment is t3; So analogize, single-chip microprocessor MCU detects and notes the time value t4 and the t6 at C, D point place respectively, then this AC power U
iTwo moment that crest took place can calculate by following formula:
AC power period T 1 can be calculated by following formula:
Like this, from second crest constantly t5 to AC power U
iTime of moment t7 of next zero crossing E, just be 1/4th of AC power period T 1, that is:
Single-chip microprocessor MCU is a reference point with t7 constantly, requirement according to phase shifting angle, single-chip microprocessor MCU is in corresponding pin output control signal, the control controllable silicon accurately triggers, trigger the silicon controlled control utmost point, as shown in Figure 3, error is minimum constantly for the zero crossing that this method obtains, and the zero crossing of obtaining for the service of next signal cycle, satisfies the application scenario that zero crossing accurately triggers constantly; Simultaneously, trigger pip is provided by single-chip microprocessor MCU, with AC power U
iSignal irrelevant; On the other hand, the size of current-limiting resistance R1 is not had strict demand, like this, the forward voltage of light emitting diode D2 not necessarily will have very wide input voltage range near zero-crossing point, and can calculate the cycle and the frequency values of input power supply.
Claims (2)
1. AC power zero-crossing detection circuit, it is characterized in that: current-limiting resistance R1 and light emitting diode D2 constitute the half-wave shaping circuit, protection diode D1 negative electrode links to each other with current-limiting resistance R1, anode connects simulation ground, and the other end of current-limiting resistance R1 connects the input end of AC power Ui; The emitter of phototriode T1 connects digitally, and its collector connects single-chip microprocessor MCU and links to each other with direct supply Vcc by another current-limiting resistance R2; At the positive half-wave of AC power Ui, light emitting diode D2 was luminous when AC power Ui voltage was higher than the operating voltage of light emitting diode D2, phototriode T1 conducting, and output voltage U o is by phototriode T1 ground connection, output low level; Light emitting diode D2 is not luminous when AC power Ui voltage is lower than the operating voltage of light emitting diode D2, and phototriode T1 ends, and output voltage U o meets DC voltage Vcc by current-limiting resistance R2, the output high level.
2.
A kind of AC power zero crossing detection method is characterized in that adopting following steps:
1) single-chip microcomputer detects the time t1 of 2 level saltus steps of preceding 1 AC power Ui positive half-wave and the value of t3;
2) single-chip microprocessor MCU is calculated the preceding 1 time crest value of t2 constantly;
3) single-chip microprocessor MCU detects the value of following 1 AC power Ui positive half-wave 2 level bound-times t4 and t6 again;
4) single-chip microprocessor MCU is calculated the value of crest time t5 this moment;
5) single-chip microprocessor MCU calculates the AC power cycle
Value;
6) single-chip microprocessor MCU is calculated next zero crossing constantly
Value;
7) single-chip microprocessor MCU keeps t1=t4, t2=t5, and these 3 of t3=t6 are worth constantly, are the service that next time detects;
8) single-chip microprocessor MCU is a reference point with t7 constantly, and according to the requirement output control signal of phase shifting angle, the control controllable silicon accurately triggers.
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| CN 201010586260 CN102062810A (en) | 2010-12-14 | 2010-12-14 | Detection circuit and method for zero crossing point of alternating current power supply |
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| CN 201010586260 CN102062810A (en) | 2010-12-14 | 2010-12-14 | Detection circuit and method for zero crossing point of alternating current power supply |
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Cited By (18)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102662104A (en) * | 2012-04-18 | 2012-09-12 | 华为技术有限公司 | Zero-crossing detection method and circuit |
| WO2013044602A1 (en) * | 2011-09-30 | 2013-04-04 | 海信科龙电器股份有限公司 | Zero-crossing signal detection circuit |
| CN103257272A (en) * | 2013-05-02 | 2013-08-21 | 江苏大学 | Power failure detection circuit and detection method for alternating current (AC) power supply |
| CN103424606A (en) * | 2013-07-26 | 2013-12-04 | 珠海钱龙载波系统有限公司 | Frequency-adaptive low-voltage power carrier communication zero-crossing detection circuit |
| CN103743940A (en) * | 2014-01-24 | 2014-04-23 | 镇江天力变压器有限公司 | Precise zero cross detection circuit for resonance current of high-frequency dedusting power supply |
| CN103743481A (en) * | 2014-02-20 | 2014-04-23 | 三维通信股份有限公司 | Extremely-low-lost detection-range-adjustable light intensity detection circuit |
| CN104237616A (en) * | 2014-09-22 | 2014-12-24 | 深圳市安邦信电子有限公司 | Voltage and current zero crossing point detection circuit of motor |
| CN104597314A (en) * | 2013-10-31 | 2015-05-06 | 博西华电器（江苏）有限公司 | Anti-interference method and device for zero-crossing point detection of household appliance and household appliance |
| CN104765299A (en) * | 2015-02-03 | 2015-07-08 | 浙江捷昌线性驱动科技股份有限公司 | Alternating current vibration motor amplitude control method and control circuit and massage bed |
| CN104833847A (en) * | 2015-04-28 | 2015-08-12 | 广东美的制冷设备有限公司 | Detection method of frequency and zero crossing point of input alternating current of air conditioning system and device |
| CN105092948A (en) * | 2015-08-25 | 2015-11-25 | 南京工程学院 | High-precision alternating-current signal zero crossing detection device and method |
| CN108005942A (en) * | 2018-01-02 | 2018-05-08 | 成都前锋电子有限责任公司 | A kind of gas instantaneous water heater AC blower fan control system |
| CN108957305A (en) * | 2018-04-28 | 2018-12-07 | 加码技术有限公司 | A kind of controlled silicon detection apparatus and detection method |
| CN109085414A (en) * | 2018-08-10 | 2018-12-25 | 深圳和而泰智能控制股份有限公司 | Voltage detection method and device |
| CN109782207A (en) * | 2019-01-30 | 2019-05-21 | 廖金群 | Zero passage detection calibration method, device, electronic equipment and storage medium |
| CN109799384A (en) * | 2017-11-16 | 2019-05-24 | 佛山市顺德区美的电热电器制造有限公司 | Voltage zero-cross detection method, device and cooking appliance |
| CN111405715A (en) * | 2020-04-03 | 2020-07-10 | 宁波科尔维特照明有限公司 | Silicon controlled rectifier dimming system and dimming method thereof |
| CN112578306A (en) * | 2020-12-28 | 2021-03-30 | 施耐德万高（天津）电气设备有限公司 | Three-phase power supply fault identification method based on phase angle monitoring |
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| WO2013044602A1 (en) * | 2011-09-30 | 2013-04-04 | 海信科龙电器股份有限公司 | Zero-crossing signal detection circuit |
| CN102662104A (en) * | 2012-04-18 | 2012-09-12 | 华为技术有限公司 | Zero-crossing detection method and circuit |
| CN102662104B (en) * | 2012-04-18 | 2015-06-17 | 华为技术有限公司 | Zero-crossing detection method and circuit |
| CN103257272A (en) * | 2013-05-02 | 2013-08-21 | 江苏大学 | Power failure detection circuit and detection method for alternating current (AC) power supply |
| CN103257272B (en) * | 2013-05-02 | 2016-03-02 | 江苏大学 | A kind of communication power supply power-fail detection circuit and detection method |
| CN103424606B (en) * | 2013-07-26 | 2016-01-13 | 珠海钱龙载波系统有限公司 | A kind of low voltage electric power carrier communication zero cross detection circuit of frequency self-adaption |
| CN103424606A (en) * | 2013-07-26 | 2013-12-04 | 珠海钱龙载波系统有限公司 | Frequency-adaptive low-voltage power carrier communication zero-crossing detection circuit |
| CN104597314A (en) * | 2013-10-31 | 2015-05-06 | 博西华电器（江苏）有限公司 | Anti-interference method and device for zero-crossing point detection of household appliance and household appliance |
| CN103743940A (en) * | 2014-01-24 | 2014-04-23 | 镇江天力变压器有限公司 | Precise zero cross detection circuit for resonance current of high-frequency dedusting power supply |
| CN103743481A (en) * | 2014-02-20 | 2014-04-23 | 三维通信股份有限公司 | Extremely-low-lost detection-range-adjustable light intensity detection circuit |
| CN103743481B (en) * | 2014-02-20 | 2017-03-15 | 三维通信股份有限公司 | A kind of adjustable light intensity detection circuit of very low cost detection range |
| CN104237616A (en) * | 2014-09-22 | 2014-12-24 | 深圳市安邦信电子有限公司 | Voltage and current zero crossing point detection circuit of motor |
| CN104237616B (en) * | 2014-09-22 | 2017-11-17 | 深圳市安邦信电子有限公司 | Electric moter voltage current zero-crossing point detects circuit |
| CN104765299A (en) * | 2015-02-03 | 2015-07-08 | 浙江捷昌线性驱动科技股份有限公司 | Alternating current vibration motor amplitude control method and control circuit and massage bed |
| CN104833847A (en) * | 2015-04-28 | 2015-08-12 | 广东美的制冷设备有限公司 | Detection method of frequency and zero crossing point of input alternating current of air conditioning system and device |
| CN104833847B (en) * | 2015-04-28 | 2017-08-25 | 广东美的制冷设备有限公司 | The frequency and detection method, the device of zero crossing of the input AC electricity of air-conditioning system |
| CN105092948A (en) * | 2015-08-25 | 2015-11-25 | 南京工程学院 | High-precision alternating-current signal zero crossing detection device and method |
| CN109799384A (en) * | 2017-11-16 | 2019-05-24 | 佛山市顺德区美的电热电器制造有限公司 | Voltage zero-cross detection method, device and cooking appliance |
| CN109799384B (en) * | 2017-11-16 | 2020-11-20 | 佛山市顺德区美的电热电器制造有限公司 | Voltage zero-crossing detection method and device and cooking appliance |
| CN108005942A (en) * | 2018-01-02 | 2018-05-08 | 成都前锋电子有限责任公司 | A kind of gas instantaneous water heater AC blower fan control system |
| CN108005942B (en) * | 2018-01-02 | 2023-11-24 | 成都前锋电子有限责任公司 | Alternating current fan control system of gas rapid water heater |
| CN108957305A (en) * | 2018-04-28 | 2018-12-07 | 加码技术有限公司 | A kind of controlled silicon detection apparatus and detection method |
| CN109085414A (en) * | 2018-08-10 | 2018-12-25 | 深圳和而泰智能控制股份有限公司 | Voltage detection method and device |
| CN109085414B (en) * | 2018-08-10 | 2021-06-11 | 深圳和而泰智能控制股份有限公司 | Voltage detection method and device |
| CN109782207A (en) * | 2019-01-30 | 2019-05-21 | 廖金群 | Zero passage detection calibration method, device, electronic equipment and storage medium |
| CN111405715A (en) * | 2020-04-03 | 2020-07-10 | 宁波科尔维特照明有限公司 | Silicon controlled rectifier dimming system and dimming method thereof |
| CN112578306A (en) * | 2020-12-28 | 2021-03-30 | 施耐德万高（天津）电气设备有限公司 | Three-phase power supply fault identification method based on phase angle monitoring |
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