CN111900007B - Method for accurately controlling phase selection closing angle - Google Patents
Method for accurately controlling phase selection closing angle Download PDFInfo
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- CN111900007B CN111900007B CN202010742840.0A CN202010742840A CN111900007B CN 111900007 B CN111900007 B CN 111900007B CN 202010742840 A CN202010742840 A CN 202010742840A CN 111900007 B CN111900007 B CN 111900007B
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
- H01H9/54—Circuit arrangements not adapted to a particular application of the switching device and for which no provision exists elsewhere
- H01H9/541—Contacts shunted by semiconductor devices
- H01H9/542—Contacts shunted by static switch means
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R19/00—Arrangements for measuring currents or voltages or for indicating presence or sign thereof
- G01R19/175—Indicating the instants of passage of current or voltage through a given value, e.g. passage through zero
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
- H01H9/54—Circuit arrangements not adapted to a particular application of the switching device and for which no provision exists elsewhere
- H01H9/56—Circuit arrangements not adapted to a particular application of the switching device and for which no provision exists elsewhere for ensuring operation of the switch at a predetermined point in the ac cycle
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
- H02H3/02—Details
- H02H3/027—Details with automatic disconnection after a predetermined time
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/30—Reactive power compensation
Abstract
The invention discloses a method for accurately controlling a phase selection closing angle, which is used for realizing the accurate control of a closing input angle of a thyristor and comprises the following steps of S1: the processor collects alternating-current voltage through a high-speed analog-to-digital conversion channel and combines a smoothing algorithm to obtain a voltage zero crossing point position; step S2: the processor acquires a voltage change period and configures a timer; step S3: the processor starts the configured timer and closes through the thyristor. The invention discloses a method for accurately controlling a phase selection closing angle, which uses software to obtain a voltage zero signal and applies a smoothing algorithm to effectively filter interference and influence caused by jitter at the voltage zero; meanwhile, the thyristor is used as an actuating mechanism for switching on, so that the response time is stable and extremely short, and the error of the actual input angle during switching on is favorably reduced.
Description
Technical Field
The invention belongs to the technical field of zero crossing point detection and phase selection closing, and particularly relates to a method for accurately controlling a phase selection closing angle.
Background
When an alternating-current low-voltage apparatus (such as a miniature circuit breaker and a leakage circuit breaker) is subjected to a short-circuit test, due to the inductive load in a loop, if the apparatus is switched on, random input angles generate uncertain transient currents, so that not only are experimental results inconsistent every time, but also the stability of the voltage of a power grid system is influenced, and even misoperation of relay protection is induced, and therefore, the input angles need to be set for the short-circuit test when the apparatus is switched on.
At present, most phase selection switching-on equipment adopts an electromechanical switching-on structure and a hardware zero crossing point detection technology, the deviation of the input angle of actual switching-on can reach +/-5 degrees, and the deviation is in a discrete state.
This solution has two drawbacks:
1. the electromechanical structure principle is that the coil is electrified to generate magnetic force to drive a mechanical device. The real-time performance of the operation is poor, and the delay time is not fixed;
2. the zero crossing point detection of hardware mostly adopts photoelectric conversion devices such as an optical coupler, and the zero point position of voltage is found by utilizing the characteristic of unidirectional isolation and conduction. But the method has the defects of poor interference resistance and slow response. In practical situations, due to factors such as power grid fluctuation and environmental electromagnetic interference, a voltage signal may fluctuate near a zero point, so that a system detects an excessive zero point signal, and misjudgment of a closing timing is caused. In addition, the response time of the photoelectric conversion device is long, so that zero point detection is inaccurate, although the response time of a certain device is relatively fixed and software can perform compensation processing, the response time of different devices is different, and compensation work is difficult.
The publication numbers are: CN106409595B entitled fast grounding switch test method and test trigger device and fast grounding switch invention patent, its technical scheme discloses the steps of, 1) releasing energy after completing the switch-on energy storage of the spring operating mechanism, the transmission connecting lever output switch-on action connected with the output connecting lever or the alternate connecting rod; 2) when the transmission crank arm rotates to a set angle, the position of the transmission crank arm is kept through the electromagnetic holding mechanism; the electromagnetic retaining mechanism is used for being matched with the transmission crank arm in a stopping way to retain the transmission crank arm when the transmission crank arm swings a set angle on a closing path of the transmission crank arm; 3) when the test loop applies short-circuit current meeting the standard requirement, the electromagnetic holding mechanism is unlocked, and the connecting lever is driven to rapidly switch on. ".
Although the above invention patent is taken as an example and the input time and the switch closing operation are mentioned, the technical problems and technical solutions thereof are different from those of the present invention. Therefore, the above problems are further improved.
Disclosure of Invention
The invention mainly aims to provide a method for accurately controlling a phase selection closing angle, which uses software to obtain a voltage zero signal and applies a smoothing algorithm to effectively filter interference and influence caused by jitter at the voltage zero; meanwhile, the thyristor is used as an actuating mechanism for switching on, so that the response time is stable and extremely short, and the error of the actual input angle during switching on is favorably reduced.
The invention also aims to provide a method for accurately controlling the phase selection closing angle, which utilizes a high-speed analog-to-digital conversion channel of a DSP (digital signal processor) and is matched with a smoothing algorithm to detect an alternating voltage zero signal in a software mode and then uses a thyristor with extremely high response speed as a closing execution mechanism to realize accurate control of the closing input angle.
In order to achieve the above object, the present invention provides a method for accurately controlling a phase selection closing angle, which is used for accurately controlling a closing input angle of a thyristor, and comprises the following steps:
step S1: the processor (the phase selection closing equipment preferably uses DSP as the processor, Digital Signal Processing, DSP for short) collects alternating voltage through a high-speed analog-to-Digital conversion channel and combines a smoothing algorithm to obtain a voltage zero crossing point position;
step S2: the processor acquires a voltage change period and configures a timer;
step S3: the processor starts a configured timer and performs closing through a thyristor (the phase selection closing device preferably takes the thyristor as an actuating mechanism for closing).
As a further preferable embodiment of the above technical means, step S1 is specifically implemented as the following steps:
step S1.1: the processor reads the current voltage value of the alternating current power grid;
step S1.2: the processor compares the read current voltage value with the voltage value read last time to judge the position of the voltage zero-crossing point;
step S1.3: the processor judges whether the number of times of the voltage zero-crossing position reaches a set value.
As a further preferred embodiment of the above technical solution, step S1.2 is specifically implemented as the following steps:
step S1.2.1: if the current voltage value and the voltage value read last time are opposite in sign, the voltage is judged to be at the zero-crossing point position and step S1.3 is executed (in other words, if the current voltage value is negative and the voltage value read last time is positive, the voltage is judged to be at the zero-crossing point position once;
step S1.2.2: if the current voltage value and the voltage value read last time are the same in sign, it is determined that the voltage is not at the zero-crossing point position and step S1.1 is performed (if the voltage values read two times are both negative or positive, it is determined that the voltage does not cross the zero-crossing point).
As a further preferred embodiment of the above technical solution, step S1.3 is specifically implemented as the following steps:
step S1.3.1: the processor judges that the number of times of the voltage zero-crossing position reaches a set value, and then executes step S2 (if the processor detects that the voltage has at least two continuous zero-crossing positions, the number of times of the voltage zero-crossing position reaches the set value);
step S1.3.2: the processor determines that the number of times of the voltage zero-crossing position does not reach the set value, then step S1.1 is performed (if the processor detects that the obtained voltage does not have 2 consecutive zero-crossing positions, it is determined that the number of times of the voltage zero-crossing position does not reach the set value, and thus the voltage value is read again).
As a further preferable embodiment of the above technical means, step S2 is specifically implemented as the following steps:
step S2.1: when the processor detects a voltage zero crossing point position each time, recording a system clock value corresponding to the voltage zero crossing point position at the moment;
step S2.2: subtracting system clock values corresponding to the zero-crossing positions of two continuous voltages to obtain the sine half-wave time of the voltage, thereby obtaining the voltage change period and judging whether the number of the voltage change periods reaches a set value;
step S2.3: the processor calculates and sequences voltage change period groups, and takes a specified number of voltage change periods in the middle to carry out mean value filtering processing so as to obtain (approximate) actual voltage change periods;
step S2.4: and converting the required input angle into input angle time according to the actual voltage change period, and configuring the input angle time as the time required by the timer to run.
As a further preferred embodiment of the above technical solution, the step S2.2 is specifically implemented as the following steps:
step S2.2.1: if the number of voltage change periods reaches the set value to form a voltage change period group, and step S2.3 is performed (in other words, assuming that the number of set values of voltage change periods is required to be 3 in order to obtain a more accurate actual voltage change period, two consecutive voltage zero-crossing positions are required for one group of voltage change periods, six consecutive voltage zero-crossing positions are required for 3 consecutive voltage change periods, and step S1.3 is re-performed if the number of voltage change periods (assumed to be 1, i.e., only two consecutive voltage zero-crossing positions) does not reach the set value);
step S2.2.2: if the number of voltage change cycles does not reach the set value, step S1.3 is performed.
As a further preferable embodiment of the above technical means, step S3 is specifically implemented as the following steps:
step S3.1: when the processor detects a voltage zero crossing point position, starting a configured timer (the previously detected continuous voltage zero crossing point position is used for configuring the timer, and the voltage zero crossing point position can be detected and switched on after the timer is configured);
step S3.2: generating an interrupt signal after the running of the configured timer is finished;
step S3.3: and (3) switching on after the thyristor receives the interrupt signal (the input angle is the required angle).
Drawings
Fig. 1 is a flowchart of a method for accurately controlling a phase selection closing angle according to the present invention.
Fig. 2 is a schematic structural diagram of a phase selection closing device of the method for accurately controlling a phase selection closing angle according to the present invention.
Detailed Description
The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.
Referring to fig. 1 of the drawings, fig. 1 is a flowchart of a method for accurately controlling a phase selection closing angle according to the present invention, and fig. 2 is a schematic structural diagram of a phase selection closing apparatus of a method for accurately controlling a phase selection closing angle according to the present invention.
In a preferred embodiment of the invention, the skilled person will note that the ac grid, thyristors, software etc. to which the invention relates may be regarded as prior art.
Preferred embodiments.
The invention discloses 1. a method for accurately controlling a phase selection closing angle, which is used for realizing the accurate control of a closing input angle of a thyristor and comprises the following steps:
step S1: the processor (the phase selection switching-on equipment preferably takes a DSP as the processor) collects alternating voltage through a high-speed analog-to-digital conversion channel and combines a smoothing algorithm to obtain a voltage zero crossing point position;
step S2: the processor acquires a voltage change period and configures a timer;
step S3: the processor starts the configured timer and performs closing through the thyristor (the phase selection closing device preferably takes the thyristor as an executing mechanism for closing).
Specifically, step S1 is implemented as the following steps:
step S1.1: the processor reads the current voltage value of the alternating current power grid;
step S1.2: the processor compares the read current voltage value with the voltage value read last time to judge the position of the voltage zero-crossing point;
step S1.3: the processor judges whether the number of times of the voltage zero-crossing position reaches a set value.
More specifically, step S1.2 is embodied as the following steps:
step S1.2.1: if the current voltage value and the voltage value read last time are opposite in sign, the voltage is judged to be at the zero-crossing point position and step S1.3 is executed (in other words, if the current voltage value is negative and the voltage value read last time is positive, the voltage is judged to be at the zero-crossing point position once;
step S1.2.2: if the current voltage value and the voltage value read last time are the same in sign, it is determined that the voltage is not at the zero-crossing point position and step S1.1 is performed (if the voltage values read two times are both negative or positive, it is determined that the voltage does not cross the zero-crossing point).
Further, step S1.3 is embodied as the following steps:
step S1.3.1: the processor judges that the number of times of the voltage zero-crossing position reaches a set value, and then executes step S2 (if the processor detects that the voltage has at least two continuous zero-crossing positions, the number of times of the voltage zero-crossing position reaches the set value);
step S1.3.2: the processor determines that the number of times of the voltage zero-crossing position does not reach the set value, then step S1.1 is performed (if the processor detects that the obtained voltage does not have 2 consecutive zero-crossing positions, it is determined that the number of times of the voltage zero-crossing position does not reach the set value, and thus the voltage value is read again).
Further, step S2 is implemented as the following steps:
step S2.1: when the processor detects a voltage zero crossing point position every time, recording a system clock value corresponding to the voltage zero crossing point position at the moment;
step S2.2: subtracting system clock values corresponding to the zero-crossing positions of two continuous voltages to obtain voltage sine half-wave time, thereby obtaining a voltage change period and judging whether the number of the voltage change period reaches a set value;
step S2.3: the processor calculates and sequences voltage change period groups, and takes a specified number of voltage change periods in the middle to carry out mean value filtering processing so as to obtain (approximate) actual voltage change periods;
step S2.4: and converting the required input angle into input angle time according to the actual voltage change period, and configuring the input angle time as the time required by the timer to run.
Preferably, step S2.2 is embodied as the following steps:
step S2.2.1: if the number of voltage change periods reaches the set value to form a voltage change period group, and step S2.3 is performed (in other words, assuming that the number of set values of voltage change periods is required to be 3 in order to obtain a more accurate actual voltage change period, two consecutive voltage zero-crossing positions are required for one group of voltage change periods, six consecutive voltage zero-crossing positions are required for 3 consecutive voltage change periods, and step S1.3 is re-performed if the number of voltage change periods (assumed to be 1, i.e., only two consecutive voltage zero-crossing positions) does not reach the set value);
step S2.2.2: if the number of voltage change cycles does not reach the set value, step S1.3 is performed.
Preferably, step S3 is embodied as the following steps:
step S3.1: when the processor detects a voltage zero crossing point position, starting a configured timer (the previously detected continuous voltage zero crossing point position is used for configuring the timer, and the voltage zero crossing point position can be detected and switched on after the timer is configured);
step S3.2: generating an interrupt signal after the running of the configured timer is finished;
step S3.3: and the thyristor is switched on after receiving the interrupt signal (the input angle is the required angle).
Preferably, the switch-on can be executed after the timer is configured, and if the timer is configured completely, the timer is not required to be configured to switch on again, but the switch-on can be directly selected.
It should be noted that the technical features of the ac power grid, the thyristor, the software, etc. related to the present patent application should be regarded as the prior art, and the specific structure, the operation principle, the control mode and the spatial arrangement mode of the technical features may be selected conventionally in the field, and should not be regarded as the invention point of the present patent, and the present patent is not further specifically described in detail.
It will be apparent to those skilled in the art that modifications and equivalents may be made in the embodiments and/or portions thereof without departing from the spirit and scope of the present invention.
Claims (4)
1. A method for accurately controlling a phase selection closing angle is used for accurately controlling a thyristor closing input angle, and is characterized by comprising the following steps of:
step S1: the processor collects alternating-current voltage through a high-speed analog-to-digital conversion channel and combines a smoothing algorithm to obtain a voltage zero crossing point position;
step S1 is specifically implemented as the following steps:
step S1.1: the processor reads the current voltage value of the alternating current power grid;
step S1.2: the processor compares the read current voltage value with the voltage value read last time to judge the position of the voltage zero-crossing point;
step S1.3: the processor judges whether the frequency of the voltage zero-crossing point position reaches a set value;
step S2: the processor acquires a voltage change period and configures a timer;
step S2 is specifically implemented as the following steps:
step S2.1: when the processor detects a voltage zero crossing point position every time, recording a system clock value corresponding to the voltage zero crossing point position at the moment;
step S2.2: subtracting system clock values corresponding to the zero-crossing positions of two continuous voltages to obtain the sine half-wave time of the voltage, thereby obtaining the voltage change period and judging whether the number of the voltage change periods reaches a set value;
step S2.3: the processor calculates and sequences voltage change period groups, and average filtering is carried out on the voltage change periods of a specified number in the middle to obtain an actual voltage change period;
step S2.4: converting the required input angle into input angle time according to the actual voltage change period, and configuring the input angle time into the time required by the timer to run;
step S3: the processor starts a configured timer and carries out closing through a thyristor;
step S3 is embodied as the following steps:
step S3.1: when the processor detects a voltage zero crossing point position, starting a configured timer;
step S3.2: generating an interrupt signal after the running of the configured timer is finished;
step S3.3: and the thyristor is switched on after receiving the interrupt signal.
2. The method for accurately controlling the phase selection closing angle according to claim 1, wherein the step S1.2 is implemented as the following steps:
step S1.2.1: if the current voltage value and the adjacent last read voltage value have opposite signs, judging that the voltage is the zero crossing point position and executing the step S1.3;
step S1.2.2: if the current voltage value and the adjacent last read voltage value have the same sign, it is determined that the voltage is not at the zero crossing point position and step S1.1 is performed.
3. The method for accurately controlling the phase selection closing angle according to claim 2, wherein the step S1.3 is implemented as the following steps:
step S1.3.1: the processor judges that the number of times of the voltage zero-crossing position reaches a set value, and executes the step S2;
step S1.3.2: and the processor judges that the number of times of the voltage zero-crossing position does not reach a set value, and executes the step S1.1.
4. The method for accurately controlling the phase selection closing angle according to claim 3, wherein the step S2.2 is implemented as the following steps:
step S2.2.1: if the number of voltage change periods reaches the set value, to form a group of voltage change periods, and perform step S2.3;
step S2.2.2: if the number of voltage change periods has not reached the set value, step S1.3 is performed.
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| CN102315045A (en) * | 2010-07-06 | 2012-01-11 | 南京南瑞继保电气有限公司 | Self-learning switching-on phase control method |
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| US7579717B2 (en) * | 2006-09-13 | 2009-08-25 | Lutron Electronics Co., Inc. | Wall-mountable timer for an electrical load |
| CN1971298B (en) * | 2006-11-28 | 2010-10-06 | 上海电器科学研究所（集团）有限公司 | Thyristor phase-selecting switch experiment device |
| CN100580835C (en) * | 2008-03-21 | 2010-01-13 | 鞍山华夏电力电子设备有限公司 | Breaker synchronous controller and control method thereof |
| CN101871965B (en) * | 2010-06-11 | 2012-01-04 | 威胜集团有限公司 | Method for detecting zero crossing time, frequency and phase difference of power sinusoidal signals |
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| CN102315045A (en) * | 2010-07-06 | 2012-01-11 | 南京南瑞继保电气有限公司 | Self-learning switching-on phase control method |
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