CN111049099B - Pre-zero brake-separating phase control method, device and system for zero-loss deep current limiting and storage medium - Google Patents
Pre-zero brake-separating phase control method, device and system for zero-loss deep current limiting and storage medium Download PDFInfo
- Publication number
- CN111049099B CN111049099B CN201911414113.5A CN201911414113A CN111049099B CN 111049099 B CN111049099 B CN 111049099B CN 201911414113 A CN201911414113 A CN 201911414113A CN 111049099 B CN111049099 B CN 111049099B
- Authority
- CN
- China
- Prior art keywords
- short
- zero
- moment
- current
- circuit
- 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.)
- Active
Links
Images
Classifications
-
- 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
- H02H3/08—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 responsive to excess current
- H02H3/093—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 responsive to excess current with timing means
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/02—Details
- H01H33/59—Circuit arrangements not adapted to a particular application of the switch and not otherwise provided for, e.g. for ensuring operation of the switch at a predetermined point in the ac cycle
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/02—Details
- H01H33/59—Circuit arrangements not adapted to a particular application of the switch and not otherwise provided for, e.g. for ensuring operation of the switch at a predetermined point in the ac cycle
- H01H33/593—Circuit arrangements not adapted to a particular application of the switch and not otherwise provided for, e.g. for ensuring operation of the switch at a predetermined point in the ac cycle for ensuring operation of the switch at a predetermined point of the ac cycle
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/26—Sectionalised protection of cable or line systems, e.g. for disconnecting a section on which a short-circuit, earth fault, or arc discharge has occured
Abstract
The invention provides a pre-zero brake-separating phase control method, equipment, a system and a storage medium for zero-loss deep current limiting, wherein the method comprises the steps of acquiring a real-time short-circuit current value and a corresponding moment of the short-circuit current value when the current of a switch branch circuit has a short-circuit fault by judging whether the switch branch circuit has the short-circuit fault or not based on an acquired real-time current value of the switch branch circuit, acquiring a short-circuit current waveform fitting curve by linearly fitting the short-circuit current value and the corresponding moment of the short-circuit current value, predicting and obtaining a first zero moment or a second zero moment of the fault current through the short-circuit current waveform fitting curve, and controlling a vacuum circuit breaker to carry out brake separation before the first zero moment or the second zero moment.
Description
Technical Field
The invention belongs to the technical field of safety of power grids, and relates to a zero-front opening phase control method, equipment, a system and a storage medium for zero-loss deep current limiting.
Background
With the continuous expansion of the capacity of the power system, the exceeding of the short-circuit current is more and more serious, which may cause the exceeding of the maximum breaking capacity of the breaker equipment, and seriously threatens the safety of the power grid and the power equipment. In order to solve the problems, at present, two solutions are provided, one is to replace a breaker with larger breaking capacity, and the other is to limit the over-standard short-circuit current by adopting a current limiting technology, but the replacement of the breaker with larger breaking capacity is difficult to popularize and apply due to high manufacturing cost and uneconomic performance.
The current limiting technology can generally consider limiting short-circuit current from three aspects of adjusting the power grid structure, changing the system operation mode and adding a current limiting device. The existing technical measures mainly include the development of a high-level voltage power grid, the adoption of direct current networking, the adoption of unit wiring for a power plant of a large-capacity unit, the split operation or bus segmentation operation of a plurality of buses, the adoption of a high-impedance transformer, the addition of a current-limiting reactor and the like, and although the measures can inhibit the fault current of the power grid to a certain extent, the problems of voltage drop, electric energy loss and the like exist. The zero-loss deep current limiting device is additionally arranged as an effective technical measure, so that the exceeding short-circuit current of the power system can be limited, the safe and reliable operation of a power grid is guaranteed, the characteristics of zero loss and zero voltage drop can be realized, and the energy-saving and consumption-reducing economic benefit and social benefit are good.
At present, when a current short circuit occurs, a vacuum circuit breaker adopting rapid opening is small in opening distance, so that the problem of electric arc reignition due to contact breakdown easily occurs when the vacuum circuit breaker is opened, the impact of fault current on equipment is increased, the service life of a contact can be influenced, and the requirement on the contact of the vacuum circuit breaker is high. In current use, a switching-off command is usually sent immediately when a short-circuit fault occurs in a circuit, switching-off may occur when a current waveform is 90 degrees, arc quenching is not facilitated when the amount of electric arc is maximum, the amount of burning is maximum, and damage to a contact is also maximum.
Disclosure of Invention
The invention provides a front-zero opening phase control method for zero-loss deep current limiting, which solves the technical problems that the short-circuit current duration is longer, the adverse effect of fault current on equipment impact is increased, and the requirement on a vacuum circuit breaker contact is higher.
The invention provides a pre-zero brake-separating phase control method for zero-loss deep current limiting, which comprises the following steps:
the method comprises the following steps:
acquiring a current value of a switch branch, and acquiring and recording a real-time current value of the switch branch and a corresponding moment of the current value;
obtaining a current slope linear fitting formula and a current slope fitting curve by performing linear fitting on the current value and the corresponding moment of the current value, and judging whether the switch branch circuit is in a pre-short circuit fault state or not according to the current change rate obtained by the current slope linear fitting formula; when the switch branch circuit has a pre-short circuit fault, acquiring a real-time pre-short circuit fault current value when the switch branch circuit has the pre-short circuit fault and a corresponding moment of the pre-short circuit fault current value;
judging whether the switch branch circuit has a short-circuit fault or not by comparing the pre-short-circuit fault current value with a preset current threshold value, and acquiring a real-time short-circuit fault current value when the switch branch circuit has a short-circuit fault and a corresponding moment of the short-circuit fault current value when the switch branch circuit has the short-circuit fault;
obtaining a short-circuit current waveform fitting curve by linearly fitting the short-circuit fault current value and the corresponding moment of the short-circuit fault current value, and predicting to obtain a first zero point moment or a second zero point moment of the corresponding moment when the current of the switch branch circuit has the short-circuit fault according to the short-circuit current waveform fitting curve;
and controlling the vacuum circuit breaker to be opened before the first zero moment or before the second zero moment according to the first zero moment or the second zero moment.
The mode of controlling the vacuum circuit breaker is specifically as follows: acquiring the moment t when the zero-loss deep current limiting device sends a brake opening command through the first zero moment or the second zero moment;
controlling the moving contact of the vacuum circuit breaker to be at the moment t before the first zero moment or the second zero moment according to the moment t when the zero-loss deep current limiting device sends a brake opening command1Starting to open the switch, the moving contact of the vacuum circuit breaker is at the time t after the first zero moment or the second zero moment2And (5) completely opening the gate.
WhereinThe inherent opening time of the vacuum circuit breaker is 5ms, t1Time of day and said t2The time length between moments is 5ms, the moment t when the zero-loss deep current limiting device sends a brake-separating command is t to the moment t when the moving contact of the vacuum circuit breaker starts to separate1Time in between is ∑ t.
The judging whether the switch branch has the pre-short circuit fault specifically comprises the following steps:
performing linear fitting on the current value acquired in the first time period to obtain a first linear fitting formula, and acquiring a first current change rate A according to the first linear fitting formula;
carrying out linear fitting on the collected current value at a second time continuous with the first time to obtain a second linear fitting formula, and obtaining a second current change rate B according to the second linear fitting formula;
and if the first current change rate A is smaller than the second current change rate B, judging that the switch branch circuit has a pre-short circuit fault.
The judging whether the short-circuit fault occurs in the switch branch circuit specifically comprises:
and if the value of the preset short-circuit fault current is larger than the preset current threshold value, judging that the switch branch circuit has a short-circuit fault.
Wherein the linear fitting by the least square method is adopted by the linear fitting of the current value and the corresponding time of the current value.
Wherein, the judgment mode for selecting the first zero point time or the second zero point time is as follows: the corresponding moment when the pre-short-circuit fault current value is larger than the preset current threshold is moment T, the moment T is the minimum value and is the short-circuit fault current moment T0, if the time period from the short-circuit fault current moment T to the first zero point moment is larger than v T, the vacuum circuit breaker is controlled to conduct switching-off before the first zero point moment, and if the time period from the short-circuit fault current moment T to the first zero point moment is smaller than or equal to v T, the vacuum circuit breaker is controlled to conduct switching-off before the second zero point moment.
The invention provides a zero-front opening phase control device for zero-loss deep current limiting, which comprises the following modules:
an acquisition module: acquiring a current value of a switch branch, and acquiring and recording a real-time current value of the switch branch and a corresponding moment of the current value;
a pre-judgment module: obtaining a current slope linear fitting formula and a current slope fitting curve by performing linear fitting on the current value and the corresponding moment of the current value, and judging whether the switch branch circuit is in a pre-short circuit fault state or not according to the current change rate obtained by the current slope linear fitting formula; when the switch branch circuit has a pre-short-circuit fault, acquiring a real-time pre-short-circuit fault current value when the switch branch circuit has a short-circuit fault and a corresponding moment of the pre-short-circuit fault current value;
a judging module: judging whether the switch branch circuit has a short-circuit fault or not by comparing the pre-short-circuit fault current value with a preset current threshold value, and acquiring a real-time short-circuit fault current value when the switch branch circuit has a short-circuit fault and a corresponding moment of the short-circuit fault current value when the switch branch circuit has the short-circuit fault;
a prediction module: obtaining a short-circuit current waveform fitting curve by linearly fitting the short-circuit fault current value and the corresponding moment of the short-circuit fault current value, and predicting to obtain a first zero point moment or a second zero point moment of the corresponding moment when the current of the switch branch circuit has the short-circuit fault according to the short-circuit current waveform fitting curve;
an execution module: and controlling the vacuum circuit breaker to be opened before the first zero moment or before the second zero moment according to the first zero moment or the second zero moment.
The invention provides a pre-zero opening gate phase control system for a zero-loss deep current limiting device, which is characterized in that the data preprocessing equipment comprises a memory, a processor and a computer program stored on the memory and capable of running on the processor, and when the computer program is executed by the processor, the steps of the pre-zero opening gate phase control method for the zero-loss deep current limiting device are realized.
The invention provides a storage medium, which is characterized in that the storage medium stores a computer program, and the computer program is executed by a processor to realize the steps of the zero-front opening phase control method for the zero-loss deep current limiting device.
According to the technical scheme, the invention has the following advantages:
the invention provides a pre-zero brake-separating phase control method, equipment, a system and a storage medium for zero-loss deep current limiting, which are used for judging whether a pre-short-circuit fault occurs in a switch branch or not by linearly fitting a current value and the corresponding moment of the current value based on the acquired real-time current value of the switch branch and obtaining the change rate of the current value, obtaining the real-time pre-short-circuit fault current value when the pre-short-circuit fault occurs in the switch branch and the corresponding moment of the pre-short-circuit fault current value when the pre-short-circuit fault occurs in the switch branch, judging whether the short-circuit fault occurs in the switch branch or not by comparing the pre-short-circuit fault current value with the preset current threshold value, obtaining the real-time short-circuit current value when the short-circuit fault occurs in the switch branch and the corresponding moment of the short-circuit current value, and linearly fitting the corresponding moment of the short-circuit current value, and acquiring the short-circuit current waveform fitting curve, predicting to obtain a first zero point moment or a second zero point moment of the short-circuit fault current through the short-circuit current waveform fitting curve, and controlling the vacuum circuit breaker to be switched off before the first zero point moment or before the second zero point moment. The vacuum circuit breaker is controlled to be opened before the zero time, the vacuum circuit breaker is controlled to be opened before the zero time of the current, a certain opening distance is formed between the two contacts and the burning quantity of the intercepted arc is smaller at the zero time, so that the fracture of the circuit breaker is prevented from being broken down and reignited by transient recovery voltage after the current passes zero, and the opening capacity of the vacuum circuit breaker is improved; the zero-point moment of the short-circuit current can be rapidly calculated through the short-circuit current waveform fitting curve, the vacuum circuit breaker is rapidly switched off before the zero-point moment of the short-circuit current, namely, the zero-loss deep current limiting device is rapidly and reliably switched into the current-limiting reactor, the overproof short-circuit current is limited in a safety range, the continuous impact of the short-circuit current on operating equipment is reduced, and the equipment safety is guaranteed. Meanwhile, the switching-off operation before the zero moment can avoid the reignition of the electric arc, the service life of the contacts at two ends of the opening distance can be prolonged, under the condition that the reignition is not needed, the contacts do not need to be subjected to strict requirements, only ordinary contacts are needed, the cost can be saved, and the contacts can be replaced at will when damaged, and the device has adaptability and flexibility.
In addition, when the first zero point moment and the second zero point moment are predicted to prevent the corresponding moment in the short-circuit fault from being close to the time of the first zero point moment, the second zero point moment is adopted for opening the brake, and sufficient time for starting opening the brake and the zero point moment is reserved, so that the standard-exceeding short-circuit current can be stably limited within a safety range.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is also possible for those skilled in the art to obtain the drawings of the current value according to the drawings without inventive exercise.
Fig. 1 is a block diagram of a phase control method of a front-zero gate separation for zero-loss deep current limiting according to an embodiment of the present invention;
fig. 2 is a block diagram of a pre-zero opening phase control apparatus for zero-loss deep current limiting according to an embodiment of the present invention.
Detailed Description
The embodiment of the invention provides a pre-zero opening phase control method, equipment, a system and a storage medium for zero-loss deep current limiting, which are used for solving the technical problems that the short-circuit current duration is long, the adverse effect of fault current on equipment impact is increased, and the requirement on a vacuum circuit breaker contact is high.
In order to make the objects, features and advantages of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the embodiments described below are only a part of the embodiments of the present invention, and not all of the embodiments. All such current values obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention are within the scope of the present invention.
When a short-circuit fault of a switch branch circuit occurs, the traditional mechanical breaker is used, and due to the fact that the opening distance is long, the reaction time is slow, and the time for impacting equipment by fault current is long; when the vacuum circuit breaker is adopted, because the opening distance of the vacuum circuit breaker is short, multiple times of electric arcs are reignited when the vacuum circuit breaker is opened, and the opening is completed only when the contact distance is increased to the point that the disconnection can be really completed, which is equivalent to the input of a current-limiting reactor, and the voltage value caused by the reignition of the opening is very high, so that the impact of fault current on equipment is increased. The arc reignition can occur between the contacts of the vacuum circuit breaker, the arc extinction can occur at the zero point moment of the current, and the arc extinction can be performed on the opening of the vacuum circuit breaker by predicting the zero point moment, so that the arc reignition between the contacts of the vacuum circuit breaker is prevented.
Referring to fig. 1, a phase control method of a front-of-zero gate separation for zero-loss deep current limiting according to an embodiment of the present invention includes:
101: acquiring a current value of a switch branch, and acquiring and recording a real-time current value of the switch branch and a corresponding moment of the current value;
102: obtaining a current slope linear fitting formula and a current slope fitting curve by performing linear fitting on the current value and the corresponding moment of the current value, and judging whether the switch branch circuit is in a pre-short circuit fault state or not according to the current change rate obtained by the current slope linear fitting formula; when the switch branch circuit has a pre-short circuit fault, acquiring a real-time pre-short circuit fault current value when the switch branch circuit has the pre-short circuit fault and a corresponding moment of the pre-short circuit fault current value;
the linear fitting of the least square method is adopted for the collected current value and the linear fitting of the current value at the corresponding moment, the slope of the current slope fitting curve, namely the current change rate, can be obtained through the current slope fitting curve and the current slope linear fitting formula of the linear fitting, and whether the switch branch circuit has the pre-short circuit fault or not is judged through the change of the current change rate, specifically: performing linear fitting on the current value acquired in the first time period to obtain a first linear fitting formula, and acquiring a first current change rate A according to the first linear fitting formula;
carrying out linear fitting on the collected current value at a second time continuous with the first time to obtain a second linear fitting formula, and obtaining a second current change rate B according to the second linear fitting formula;
and if the first current change rate A is smaller than the second current change rate B, judging that the switch branch circuit has a pre-short circuit fault.
If the first current change rate a is smaller than the second current change rate B, it may be determined that the current has a sudden change, and it may be accurately and quickly determined that the current of the switching branch has changed, but the current change may not be determined whether the current is a short circuit, and it may be determined whether the switching branch has a short circuit fault more accurately by further screening and determining.
103: judging whether the switch branch circuit has a short-circuit fault or not by comparing the pre-short-circuit fault current value with a preset current threshold value, and acquiring a real-time short-circuit fault current value when the switch branch circuit has a short-circuit fault and a corresponding moment of the short-circuit fault current value when the switch branch circuit has the short-circuit fault;
through the judgment of the pre-short-circuit fault of the switch branch, it can be firstly determined that the current change occurs on the switch branch, but the current change is not necessarily caused only by the short-circuit fault, and the short-circuit fault of the switch branch can be accurately judged by further screening judgment, so that the judgment of whether the short-circuit fault of the switch branch occurs is specifically as follows:
and if the value of the preset short-circuit fault current is larger than the preset current threshold value, judging that the switch branch circuit has a short-circuit fault.
After the pre-short-circuit fault judgment is carried out on the switch branch, the acquired pre-short-circuit fault current value of the switch branch is further compared with the preset current threshold value, so that the short-circuit fault of the switch branch can be accurately judged, and the condition of misjudgment is avoided.
104: obtaining a short-circuit current waveform fitting curve by linearly fitting the short-circuit fault current value and the corresponding moment of the short-circuit fault current value, and predicting to obtain a first zero point moment or a second zero point moment of the corresponding moment when the current of the switch branch circuit has the short-circuit fault according to the short-circuit current waveform fitting curve;
the method comprises the steps that a current waveform when short circuit does not occur conforms to a sinusoidal expression of current, harmonic waves can occur after short circuit occurs, so that the current waveform changes, at the moment, a short-circuit current waveform fitting curve is fitted by obtaining a real-time short-circuit current value of the short-circuit current and the corresponding moment of the short-circuit current value, the corresponding moment of the short-circuit fault is found out on the short-circuit current waveform fitting curve, and the first zero point moment or the second zero point moment of the corresponding moment of the short-circuit fault is obtained, namely the next zero point moment or the next two zero point moments of the corresponding moment of the short-circuit fault are obtained.
105: and controlling the vacuum circuit breaker to be opened before the first zero moment or before the second zero moment according to the first zero moment or the second zero moment.
The mode of controlling the vacuum circuit breaker is specifically as follows: acquiring the moment t when the zero-loss deep current limiting device sends a brake opening command through the first zero moment or the second zero moment;
controlling the moving contact of the vacuum circuit breaker according to the moment t when the zero-loss deep current limiting device sends a brake-separating commandAt a time t before the first zero point time or before the second zero point time1Starting to open the switch, the moving contact of the vacuum circuit breaker is at the time t after the first zero moment or the second zero moment2And (5) completely opening the gate. Wherein the inherent opening time of the vacuum circuit breaker is 5ms, t1Time of day and said t2The time length between moments is 5ms, the moment t when the zero-loss deep current limiting device sends a brake-separating command is t to the moment t when the moving contact of the vacuum circuit breaker starts to separate1Time in between is ^ t, which is 3 ms.
Further, a determination method of selecting the first zero point time or the second zero point time is: the corresponding moment when the value of the pre-short-circuit fault current is larger than the preset current threshold is a moment T, and the moment T which is the minimum value is a short-circuit fault current moment T0If the time interval between the short-circuit fault current moment t and the first zero moment is greater than v t, controlling the vacuum circuit breaker to conduct opening before the first zero moment, and if the time interval between the short-circuit fault current moment t and the first zero moment is less than or equal to v t, controlling the vacuum circuit breaker to conduct opening before the second zero moment.
And controlling the zero moment in the switching-off process of the vacuum circuit breaker by receiving the switching-off command before the zero moment, which is issued by the zero loss depth limiting device. The situation that the electric arc reignites when the voltage exceeds the dielectric insulation recovery voltage between the contacts is avoided.
The smaller the combustion quantity of the opening and the closure electric arc of the vacuum circuit breaker before the current zero passage is smaller, the larger opening distance can be opened before the current zero passage, the breaker fracture after the current zero passage is prevented from being broken down and reignited by transient recovery voltage, and the opening and closing capacity of the vacuum circuit breaker is improved; meanwhile, the current change rate is used for carrying out pre-judgment, the short-circuit fault current of the switch branch circuit is judged by comparing the pre-short-circuit fault current value with the preset current threshold value, whether the short-circuit fault occurs in the switch branch circuit can be judged quickly and accurately, the position of the first zero point moment or the second zero point moment of the short-circuit current can be predicted quickly through the short-circuit current waveform fitting curve, the vacuum circuit breaker can be switched off at the short-circuit current zero crossing point moment through the fitting zero-loss depth current limiting device, the exceeding short-circuit current is limited in a safety range, the continuous impact of the short-circuit current on operating equipment is reduced, and the safety of the equipment is guaranteed.
As shown in fig. 2, another embodiment of the present invention provides a pre-zero opening phase control device for zero-loss deep current limiting, which includes the following modules:
the acquisition module 201: collecting the current value of the switch branch, obtaining and recording the real-time current value of the switch branch and the corresponding moment of the current value
The pre-judgment module 202: obtaining a current slope linear fitting formula and a current slope fitting curve by performing linear fitting on the current value and the corresponding moment of the current value, and judging whether the switch branch circuit is in a pre-short circuit fault state or not according to the current change rate obtained by the current slope linear fitting formula; when the switch branch circuit has a pre-short-circuit fault, acquiring a real-time pre-short-circuit fault current value when the switch branch circuit has a short-circuit fault and a corresponding moment of the pre-short-circuit fault current value;
the judging module 203: judging whether the switch branch circuit has a short-circuit fault or not by comparing the pre-short-circuit fault current value with a preset current threshold value, and acquiring a real-time short-circuit fault current value when the switch branch circuit has a short-circuit fault and a corresponding moment of the short-circuit fault current value when the switch branch circuit has the short-circuit fault;
the prediction module 204: obtaining a short-circuit current waveform fitting curve by linearly fitting the short-circuit fault current value and the corresponding moment of the short-circuit fault current value, and predicting and obtaining a first zero point moment of the corresponding moment when the current of the switch branch circuit has the short-circuit fault according to the short-circuit current waveform fitting curve;
the execution module 205: and controlling the vacuum circuit breaker to be opened before the first zero moment or before the second zero moment according to the first zero moment or the second zero moment.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
Another embodiment of the present invention provides a pre-zero gate-separating phase control system for zero-loss deep current limiting, the data preprocessing device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and when the computer program is executed by the processor, the steps of the pre-zero gate-separating phase control method for zero-loss deep current limiting apparatus are implemented.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
Another embodiment of the present invention provides a storage medium having a computer program stored thereon, wherein the computer program, when being executed by a processor, implements the steps of the method for controlling the front-zero gate-breaking phase of the zero-loss deep current limiting device as described above.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways by using the described current values. For example, the above-described embodiments of the apparatus are merely illustrative, and for example, the division of the units is only the division of the logic function of the pre-zero split gate phase control method for zero-loss deep current limiting, and there may be other division manners in practical implementation, for example, a plurality of units or components may be combined or may be integrated into another system, or some features may be omitted or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in the form of electric, mechanical or said current value.
The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.
The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.
As described above, the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the current value; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the current value can still be modified in the technical solutions described in the foregoing embodiments, or some technical features of the current value can be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (9)
1. A pre-zero opening gate phase control method for a zero-loss deep current limiting device is characterized by comprising the following steps:
acquiring a current value of a switch branch, and acquiring and recording a real-time current value of the switch branch and a corresponding moment of the current value;
obtaining a current slope linear fitting formula and a current slope fitting curve by performing linear fitting on the current value and the corresponding moment of the current value, and judging whether the switch branch circuit is in a pre-short circuit fault state or not according to the current change rate obtained by the current slope linear fitting formula; when the switch branch circuit has a pre-short circuit fault, acquiring a real-time pre-short circuit fault current value when the switch branch circuit has the pre-short circuit fault and a corresponding moment of the pre-short circuit fault current value;
judging whether the switch branch circuit has a short-circuit fault or not by comparing the pre-short-circuit fault current value with a preset current threshold value, and acquiring a real-time short-circuit fault current value when the switch branch circuit has a short-circuit fault and a corresponding moment of the short-circuit fault current value when the switch branch circuit has the short-circuit fault;
obtaining a short-circuit current waveform fitting curve by linearly fitting the short-circuit fault current value and the corresponding moment of the short-circuit fault current value, and predicting to obtain a first zero point moment or a second zero point moment of the corresponding moment when the current of the switch branch circuit has the short-circuit fault according to the short-circuit current waveform fitting curve;
acquiring the moment t when the zero-loss deep current limiting device sends a brake opening command according to the first zero moment or the second zero moment;
controlling vacuum according to the moment t when the zero-loss depth current limiting device sends a brake opening commandThe moving contact of the circuit breaker is at a time t before the first zero moment or before the second zero moment1Starting to open the switch, the moving contact of the vacuum circuit breaker is at the time t after the first zero moment or the second zero moment2And (5) completely opening the gate.
2. The phase control method for zero-front opening of zero-loss deep current limiting device according to claim 1, characterized in that the inherent opening time of the vacuum circuit breaker is 5ms, and the t is t1Time of day and said t2The time length between moments is 5ms, the moment t when the zero-loss deep current limiting device sends a brake-separating command is t to the moment t when the moving contact of the vacuum circuit breaker starts to separate1Time in between is ∑ t.
3. The method for controlling the front-zero opening brake phase of the zero-loss deep current limiting device according to claim 1, wherein the step of judging whether the switching branch has the pre-short-circuit fault specifically comprises the following steps:
performing linear fitting on the current value acquired in the first time period to obtain a first linear fitting formula, and acquiring a first current change rate A according to the first linear fitting formula;
carrying out linear fitting on the collected current value at a second time continuous with the first time to obtain a second linear fitting formula, and obtaining a second current change rate B according to the second linear fitting formula;
and if the first current change rate A is smaller than the second current change rate B, judging that the switch branch circuit has a pre-short circuit fault.
4. The method for controlling the front-zero opening brake phase of the zero-loss deep current limiting device according to claim 1, wherein the step of judging whether the switching branch has the short-circuit fault specifically comprises the following steps:
and if the value of the preset short-circuit fault current is larger than the preset current threshold value, judging that the switch branch circuit has a short-circuit fault.
5. The method of claim 1, wherein the linear fitting of least squares is used to fit the current values and their corresponding times.
6. The phase control method of the front-zero opening brake for the zero-loss deep current limiting device according to claim 2, wherein the judgment mode of selecting the first zero point moment or the second zero point moment is as follows: the corresponding moment when the value of the pre-short-circuit fault current is larger than the preset current threshold is a moment T, and the moment T which is the minimum value is a short-circuit fault current moment T0If the time interval between the short-circuit fault current moment t and the first zero moment is greater than v t, controlling the vacuum circuit breaker to conduct opening before the first zero moment, and if the time interval between the short-circuit fault current moment t and the first zero moment is less than or equal to v t, controlling the vacuum circuit breaker to conduct opening before the second zero moment.
7. A front-zero opening brake phase control device for a zero-loss deep current limiting device is characterized by comprising the following modules:
an acquisition module: acquiring a current value of a switch branch, and acquiring and recording a real-time current value of the switch branch and a corresponding moment of the current value;
a pre-judgment module: obtaining a current slope linear fitting formula and a current slope fitting curve by performing linear fitting on the current value and the corresponding moment of the current value, and judging whether the switch branch circuit is in a pre-short circuit fault state or not according to the current change rate obtained by the current slope linear fitting formula; when the switch branch circuit has a pre-short-circuit fault, acquiring a real-time pre-short-circuit fault current value when the switch branch circuit has a short-circuit fault and a corresponding moment of the pre-short-circuit fault current value;
a judging module: judging whether the switch branch circuit has a short-circuit fault or not by comparing the pre-short-circuit fault current value with a preset current threshold value, and acquiring a real-time short-circuit fault current value when the switch branch circuit has a short-circuit fault and a corresponding moment of the short-circuit fault current value when the switch branch circuit has the short-circuit fault;
a prediction module: obtaining a short-circuit current waveform fitting curve by linearly fitting the short-circuit fault current value and the corresponding moment of the short-circuit fault current value, and predicting to obtain a first zero point moment or a second zero point moment of the corresponding moment when the current of the switch branch circuit has the short-circuit fault according to the short-circuit current waveform fitting curve;
an execution module: acquiring the moment t when the zero-loss deep current limiting device sends a brake opening command according to the first zero moment or the second zero moment; controlling the moving contact of the vacuum circuit breaker to be at the moment t before the first zero moment or the second zero moment according to the moment t when the zero-loss deep current limiting device sends a brake opening command1Starting to open the switch, the moving contact of the vacuum circuit breaker is at the time t after the first zero moment or the second zero moment2And (5) completely opening the gate.
8. A pre-zero gate-separating phase control system for a zero-loss deep current limiting device, wherein a data preprocessing device in the system comprises a memory, a processor and a computer program stored on the memory and capable of running on the processor, and when the computer program is executed by the processor, the steps of the pre-zero gate-separating phase control method for the zero-loss deep current limiting device are realized according to any one of claims 1 to 6.
9. A storage medium having stored thereon a computer program which, when executed by a processor, implements the steps of a pre-zero split gate phase control method for a zero-loss deep current limiting device according to any one of claims 1 to 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911414113.5A CN111049099B (en) | 2019-12-31 | 2019-12-31 | Pre-zero brake-separating phase control method, device and system for zero-loss deep current limiting and storage medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911414113.5A CN111049099B (en) | 2019-12-31 | 2019-12-31 | Pre-zero brake-separating phase control method, device and system for zero-loss deep current limiting and storage medium |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111049099A CN111049099A (en) | 2020-04-21 |
| CN111049099B true CN111049099B (en) | 2022-04-29 |
Family
ID=70242660
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911414113.5A Active CN111049099B (en) | 2019-12-31 | 2019-12-31 | Pre-zero brake-separating phase control method, device and system for zero-loss deep current limiting and storage medium |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111049099B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111952948B (en) * | 2020-08-18 | 2023-04-25 | 广东电网有限责任公司 | Zero-loss deep current limiting device and power transmission line short-circuit fault current limiting method |
| US20240118350A1 (en) * | 2022-10-05 | 2024-04-11 | Hong Kong Applied Science And Technology Research Institute Co., Ltd. | Method of Identifying a Short-Circuit Like Event in a Circuit Breaker |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106300306A (en) * | 2016-08-28 | 2017-01-04 | 安徽普天电力科技有限公司 | A kind of transformator zero consumes degree of depth current limiting system |
| CN109245034A (en) * | 2018-09-12 | 2019-01-18 | 山东电力设备有限公司 | Mechanical high-voltage dc circuit breaker Control and protection system and its control method |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2495745A1 (en) * | 2011-03-04 | 2012-09-05 | ABB Technology AG | Current-rise limitation in high-voltage DC systems |
| CN104393583A (en) * | 2014-11-27 | 2015-03-04 | 瓮福（集团）有限责任公司 | Short-circuit fault current limiting device |
| SE539392C2 (en) * | 2015-12-28 | 2017-09-12 | Scibreak Ab | Arrangement, system, and method of interrupting current |
| CN106680704B (en) * | 2017-01-12 | 2019-06-25 | 中国计量大学 | Combination switch and its operating passing zero control and itself switching fault judgment method |
-
2019
- 2019-12-31 CN CN201911414113.5A patent/CN111049099B/en active Active
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106300306A (en) * | 2016-08-28 | 2017-01-04 | 安徽普天电力科技有限公司 | A kind of transformator zero consumes degree of depth current limiting system |
| CN109245034A (en) * | 2018-09-12 | 2019-01-18 | 山东电力设备有限公司 | Mechanical high-voltage dc circuit breaker Control and protection system and its control method |
Non-Patent Citations (1)
| Title |
|---|
| 10kV零损耗深度限流装置技术研究;范德和 等;《广东电力》;20190827;第32卷(第8期);17-23 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111049099A (en) | 2020-04-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111049099B (en) | Pre-zero brake-separating phase control method, device and system for zero-loss deep current limiting and storage medium | |
| CN104362599A (en) | Method for protecting low-voltage bus of intelligent substation | |
| CN108051736B (en) | Test evaluation method and system for switching equipment with capacitive current frequently switched on and switched off | |
| CN101521407B (en) | Three-segment out-of-step self-adaptive disconnecting method | |
| CN111243900A (en) | Liquid sulfur hexafluoride arc voltage transfer type direct current circuit breaker and control method thereof | |
| CN106253321B (en) | A kind of optimization method of DC control and protection system commutation failure PREDICTIVE CONTROL | |
| CN109800453B (en) | Parameter optimization method for fast switching type current limiter and circuit breaker | |
| Razi-Kazemi et al. | A new realistic transient model for restrike/prestrike phenomena in vacuum circuit breaker | |
| CN109613422B (en) | Circuit breaker tripping time control method for suppressing secondary arc current | |
| CN105388415B (en) | Circuit breaker on-off TRV capability evaluation method based on two-segment time scale | |
| CN104578105A (en) | Intelligent switching device and method of paralleling reactor | |
| CN112542823B (en) | Reclosing control method and system and reclosing control equipment | |
| CN109599748B (en) | Control method and device for short-circuit current of transformer substation, storage medium and processor | |
| CN109617031A (en) | A kind of power distribution network short circuit accident protection processing system | |
| CN109672160A (en) | The method for limiting of ultra-high voltage transformer station lightning ingress overvoltage | |
| CN111244907B (en) | On-off time sequence control method and system of breaker in transformer substation | |
| Yang et al. | Shipping distribution networks short circuit selective protection method base on fast recovery power breaker | |
| CN113076643A (en) | Method and system for analyzing rapid transient overvoltage signal | |
| CN105048411A (en) | 220 kV transformer neutral point gap action control device and method | |
| CN112260243B (en) | Method for reducing short-circuit current of transformer substation by using fault current limiter | |
| CN104377649A (en) | Automatic switching method of transformer neutral grounding knife-switch | |
| Thomas et al. | A Method for Controlled Fault Interruption for Use with HV SF 6 Circuit Breakers | |
| Guan et al. | Study on Short-circuit current interruption characteristics of Double-break fast vacuum circuit breaker within the minimum arcing time | |
| Dohnke et al. | Edge Devices, Sensors, Cloud for High Voltage Switchgears | |
| CN112186720B (en) | High-speed short circuit current limiting device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |