CN103779827A - Method for secondary automatic reclosing lock of extra-high voltage power transmission line - Google Patents

Abstract

The invention discloses a secondary automatic reclosing method of an ultra-high voltage transmission line. When the allowable condition of the secondary reclosing is satisfied, if the line protection trips, the secondary reclosing is started after the tripping ends. After adopting the above scheme, the allowed reclosing conditions of primary reclosing and secondary reclosing can be set to different conditions, so that only the primary reclosing is blocked under certain conditions, and the secondary reclosing can act instead of manual closing.

Description

A secondary automatic reclosing method for ultra-high voltage transmission lines

technical field

The invention relates to an automatic reclosing technology of an ultra-high voltage transmission line, in particular to a technology for a secondary automatic reclosing after the primary reclosing fails.

Background technique

In the reclosing technology of the ultra-high voltage power grid transmission line, one-time automatic reclosing refers to: after a fault, only one automatic closing operation is performed at most.

The realization method of one-time automatic reclosing is generally as follows: when the line is in normal operation, the allowable condition of reclosing is set to be satisfied; when the line is faulty and tripped, if the allowable condition of reclosing is satisfied, a reclosing command is issued after a set delay; the reclosing command After sending out, immediately set the reclosing permitting condition as unsatisfied, so that the reclosing will no longer act.

Secondary auto-reclosing means: After the first auto-reclosing failure, the auto-reclosing operation will be performed again after a set delay. In the current ultra-high voltage power grid, the automatic reclosing technology of transmission lines generally adopts primary automatic reclosing, and the secondary automatic reclosing is rarely used, and there are problems. In some cases, the primary automatic reclosing is blocked, but it is hoped that the secondary automatic The reclosing switch can act instead of manual closing, and the existing secondary automatic reclosing method cannot meet this requirement.

Contents of the invention

The object of the present invention is to provide a secondary automatic reclosing method of an ultra-high voltage transmission line to solve the above-mentioned problems existing in the current secondary reclosing.

In order to achieve the above object, the solution of the present invention is to judge respectively whether the allowable conditions of the primary reclosing and the secondary reclosing are satisfied; If the line protection trips, the secondary reclosing switch is started after the tripping ends.

Further, after starting the secondary recloser, it also includes: judging whether a serious fault occurs according to the fault characteristics, and blocking the secondary recloser when a serious fault occurs.

Further, in the one-and-a-half switch wiring mode, after starting the secondary reclosing, it also includes: exchanging signals between the secondary reclosing of the first-closing switch and the secondary reclosing of the second-closing switch, so as to realize the first closing and the second closing switch.

Further, judging whether the condition for allowing reclosing of one-time reclosing is satisfied is specifically: when the line is operating normally, the switch is in the closing position, and there is no condition for blocking one-time reclosing, after a delay, the allowing condition for one-time reclosing is satisfied; If there is a condition for blocking one-time reclosing, or a one-time reclosing command is issued, set the permission condition of one-time reclosing not satisfied; the condition for blocking one-time reclosing is set according to actual needs.

Further, judging whether the condition for allowing reclosing of the secondary reclosing is satisfied is specifically: when the line is operating normally, the switch is in the closing position, and there is no condition for blocking the secondary reclosing, after a delay, set the secondary reclosing to allow The condition is satisfied; if there is a condition for blocking the secondary reclosing, or if a secondary reclosing command is issued, the allowable condition for the secondary reclosing is not satisfied; the condition for blocking the secondary reclosing is set according to actual needs.

Further, the serious faults include but are not limited to the following faults: (a) multi-phase short-circuit fault, (b) three-phase short-circuit fault, (c) single-phase-to-ground short-circuit fault at the outlet; the serious fault is set according to actual needs.

Further, the discriminating a serious fault according to the fault characteristics specifically refers to comprehensively judging according to the three-phase voltage of the faulty line, the three-phase current flowing through the corresponding switch of the faulty line, and the line protection trip signal.

Further, exchanging signals between the secondary reclosing of the first-closing switch and the secondary reclosing of the post-closing switch to realize switching between first-closing and post-closing specifically refers to: setting the reclosing of the two switches as first-closing respectively switch and the rear-closing switch, the delays of the secondary reclosing of the two switches are set to be equal; when the two switches are put into operation, after the secondary reclosing of the first-closing switch is started, the The secondary reclosing of the rear-closing switch sends out a blocking and first-closing signal, so that the delay time of the secondary reclosing of the rear-closing switch is increased to realize sequential closing; when the first-closing switch exits operation, no signal is issued. The first closing signal is blocked, the second reclosing delay of the second closing switch is not increased, and the reclosing is performed according to the delay of the first closing switch.

In addition, the present invention also provides a secondary automatic reclosing method of an ultra-high voltage transmission line. After the secondary reclosing is started, it is judged whether a serious fault occurs according to the fault characteristics, and the secondary reclosing is blocked when a serious fault occurs.

In addition, the present invention also provides a secondary automatic reclosing method of an ultra-high voltage transmission line. In a half-switch wiring mode, signals are exchanged between the secondary reclosing of the first-closing switch and the secondary reclosing of the last-closing switch to realize Switching between first and last.

After adopting the above scheme, the allowed reclosing conditions of primary reclosing and secondary reclosing can be set to different conditions, so that only the primary reclosing is blocked under certain conditions, and the secondary reclosing can act instead of manual closing.

Description of drawings

Fig. 1 is a logic diagram for judging the allowable conditions of primary reclosing and the permitted conditions of secondary reclosing according to the embodiment of the present invention

Fig. 2 is a logic diagram of secondary reclosing for severe fault blocking according to the embodiment of the present invention

Fig. 3 is a logical diagram of secondary reclosing of the first-close switch and the last-close switch according to the embodiment of the present invention

Detailed ways

The technical solution of the present invention will be described in detail below in conjunction with accompanying drawing 1 .

The invention provides a secondary automatic reclosing method of an ultra-high voltage line, which improves the existing secondary reclosing method so as to meet the following requirements: (1) In some cases, the primary reclosing is blocked, and the secondary reclosing The brake can still operate instead of manual closing; (2) Under some serious faults, the secondary reclosing can be blocked; (3) In the main wiring mode of one and a half switches, the two switches involved in the secondary reclosing operation are in accordance with When the scheduled closing sequence is closed, and the first-closing switch is out of operation, the closing delay of the last-closing switch is automatically shortened. Concrete content of the present invention is:

Respectively determine whether the allowable conditions of the primary reclosing and the secondary reclosing are met, and when the permissible conditions of the primary reclosing are not satisfied and the secondary reclosing is satisfied, if the line protection trips, start the Describe the secondary reclosing.

In addition, under some serious faults, the reclosing fault has a greater impact on the power grid. In order to ensure the stability of the system, it is hoped that the secondary automatic reclosing will not operate. Therefore, the present invention further includes, after starting the secondary reclosing switch, further comprising: judging whether a serious fault occurs according to the fault characteristics, and blocking the secondary reclosing switch when a serious fault occurs.

Distinguish whether a serious fault occurs according to the fault characteristics, and block the secondary reclosing when a serious fault occurs. It can also be applied to the scheme of using other methods to judge the condition of the secondary reclosing, and is not limited to the discrimination method proposed by the present invention. After the secondary reclosing is started, serious faults can be judged, and there is no restriction on how to start it.

In the main wiring mode of one and a half switches, one closing operation involves the closing of two switches. During the second automatic reclosing, it is hoped that the two switches will be closed according to the predetermined sequence, and when the first closing switch exits operation, the second closing The switch's secondary reclosing delay is automatically shortened. Therefore, the present invention further includes, in the one-and-a-half switch wiring mode, after starting the secondary reclosing, it also includes: exchanging signals between the secondary reclosing of the first closing switch and the secondary reclosing of the subsequent closing switch, so as to realize the first Combined and post-combined switching.

The switching of closing first and closing later can also be applied to the scheme of judging the condition of secondary reclosing in other ways, and is not limited to the judging way proposed in the present invention.

Embodiments of the present invention will be described below in conjunction with the accompanying drawings.

Accompanying drawing 1 is an embodiment of the present invention, and in conjunction with Fig. 1, the process of judging the allowable conditions of this first and second reclosing is described.

When the line is running normally, the switch is in the closed position, and there is no condition for blocking one-time reclosing, after a fixed delay, the allowable condition for one-time reclosing is satisfied; if there is a condition for blocking one-time reclosing, or a one-time reclosing command is issued, The allowable condition for setting one-shot reclosing is not satisfied.

When the line is running normally, the switch is in the closed position, and there is no condition for blocking the second reclosing, after a fixed delay, the allowable condition for the second reclosing is satisfied; if there is a condition for blocking the second reclosing, or the second reclosing The brake command is issued, and the allowable condition of the secondary reclosing is not satisfied.

The conditions for blocking the primary reclosing and blocking the secondary reclosing can be set separately according to requirements, and can be the same or different.

The embodiment of accompanying drawing 2 illustrates how to judge whether a serious fault occurs according to the fault characteristics, and block the secondary reclosing when a serious fault occurs.

Serious faults may include but are not limited to the following types of faults: (a) multi-phase short circuit fault, (b) three-phase short circuit fault, (c) single-phase ground short circuit at the outlet. Among them, (a) includes (b), that is, multi-phase short-circuit faults include three-phase short-circuit faults.

The serious failure can be set according to actual needs. For example, the serious failure can be set to include the above (a), and when the failure type is judged to be (a), it is considered that a serious failure has occurred, otherwise it is considered that no serious failure has occurred.

If it is selected to block the secondary reclosing for serious faults, after the occurrence of serious faults is judged, the allowable condition for secondary reclosing is not satisfied to realize the blocking of secondary reclosing; if it is selected to not block the secondary reclosing for serious faults, then After a serious fault is identified, it will not affect the allowable conditions for secondary reclosing. As shown in Figure 2.

For the judgment of serious faults, a comprehensive judgment can be made based on the three-phase voltage of the faulty line, the three-phase current flowing through the corresponding switch of the faulty line, and the line protection trip signal. The specific judgment method can be set according to the needs. For example, setting serious faults includes the above (a), and the method of judging serious faults can be: if the current amplitude of a certain phase is greater than the set threshold value, and the voltage amplitude is smaller than the set threshold value, it is judged that the phase is a faulty phase ; If the phase-to-phase current amplitude of a certain two phases is greater than the set threshold value, and the phase-to-phase voltage amplitude is less than the set threshold value, it is judged that the two phases are faulty phases; if two or three phases are judged as faulty phases, It is considered a multi-phase short-circuit fault, that is, a serious fault occurs. The above-mentioned identification methods are just examples, and the actual identification methods are not limited to the above-mentioned methods.

Referring to the embodiment of the accompanying drawing 3, under the one-and-a-half switch wiring mode, signals are exchanged between the secondary reclosing of the first-closing switch and the secondary reclosing of the last-closing switch, and the switching between the first-closing and the second-closing is automatically realized.

Through the parameter setting, the reclosing of the two switches is set as the first closing switch and the second closing switch respectively, and the delay of the second reclosing of the two switches is set to be equal. When both switches are put into operation, after the secondary reclosing of the first-closing switch starts, it will send a signal of blocking and first closing to the secondary reclosing of the rear-closing switch; , the secondary reclosing delay increases by a fixed time (the length of this fixed time can be set). The actual reclosing delay of the first-closing switch is equal to the set reclosing delay, and the reclosing delay of the last-closing switch is the set reclosing delay plus the added delay of the last-closing switch; when the first-closing switch exits operation, it will not When the blocking first closing signal is issued, the secondary reclosing delay of the rear closing switch does not increase, that is, it is automatically converted from the latter closing to the first closing.

The above embodiments are only to illustrate the technical ideas of the present invention, and can not limit the protection scope of the present invention with this. All technical ideas proposed in accordance with the present invention, any changes made on the basis of technical solutions, all fall within the protection scope of the present invention. Inside.

Claims (10)

1. A secondary automatic reclosing method for an ultra-high voltage transmission line, characterized in that: judge whether a reclosing switch and a secondary reclosing allowable condition are satisfied respectively; When the allowable condition of reclosing is satisfied, if the line protection trips, the secondary reclosing is started after the tripping ends. 2. The method for secondary automatic reclosing of ultra-high voltage transmission lines according to claim 1, characterized in that: after said starting said secondary reclosing, it also includes: judging whether a serious fault occurs according to the fault characteristics, when a serious fault occurs Block the secondary recloser. 3. The secondary automatic reclosing method of an ultra-high voltage transmission line as claimed in claim 1, characterized in that: in the one-and-a-half switch wiring mode, after said starting said secondary reclosing, it also includes: first closing the two switches of the switch. Signals are exchanged between the secondary reclosing switch and the secondary reclosing switch of the post-closing switch to realize the switching between the first closing and the later closing. 4. The method for secondary automatic reclosing of ultra-high voltage transmission lines as claimed in claim 1, wherein said judging whether the condition for allowing reclosing of primary reclosing is satisfied is specifically: when the line is in normal operation, the switch is in the closing position, and If there is no condition for blocking one-time reclosing, after a delay, the allowable condition for one-time reclosing is satisfied; if there is a condition for blocking one-time reclosing, or a reclosing command is issued, the one-time reclosing permission condition is not satisfied ; The conditions for blocking the primary reclosing are set according to actual needs. 5. The method for secondary automatic reclosing of an ultra-high voltage transmission line according to claim 1, wherein the judgment of whether the condition for allowing reclosing of the secondary reclosing is satisfied is specifically: when the line is in normal operation, the switch is in the closing position, And there is no condition for blocking the secondary reclosing, after a delay, set the allowable condition of the secondary reclosing to be satisfied; The allowable condition for reclosing is not satisfied; the condition for blocking the secondary reclosing is set according to actual needs. 6. A method for secondary automatic reclosing of ultra-high voltage transmission lines as claimed in claim 2, characterized in that said serious faults include but not limited to the following faults: (a) multi-phase short-circuit fault, (b) three-phase short-circuit Fault, (c) single-phase-to-ground short-circuit fault at the outlet; the serious fault is set according to actual needs. 7. The secondary automatic reclosing method of an ultra-high voltage transmission line as claimed in claim 2, wherein said discriminating a serious fault according to the fault characteristics specifically refers to: according to the three-phase voltage of the faulty line, the corresponding switching current of the faulty line Comprehensively judge the over three-phase current and line protection trip signal. 8. A method for secondary automatic reclosing of an ultra-high voltage transmission line as claimed in claim 3 or 5, characterized in that signals are exchanged between the secondary reclosing of the first-closing switch and the secondary reclosing of the post-closing switch , realizing the switching between closing first and closing specifically refers to: setting the reclosing switches of the two switches as the first closing switch and the latter closing switch respectively, and setting the delays of the secondary reclosing of the two switches to be equal; when the When both switches are put into operation, after the secondary reclosing of the first-closing switch is started, a blocking first-closing signal is sent to the secondary reclosing of the rear-closing switch, so that the secondary reclosing of the latter-closing switch is delayed. When the delay time is increased to realize closing in sequence; when the first-closing switch exits operation, the locking first-closing signal is not sent out, and the secondary reclosing delay of the latter-closing switch does not increase, according to the set The delay of the above-mentioned pre-closing switch is used for reclosing. 9. A secondary automatic reclosing method for an ultra-high voltage transmission line, characterized in that: after the secondary reclosing is started, it is judged whether a serious fault occurs according to the fault characteristics, and the secondary reclosing is blocked when a serious fault occurs. 10. A secondary automatic reclosing method for extra-high voltage transmission lines, characterized in that: under the one-and-a-half switch wiring mode, signals are exchanged between the secondary reclosing of the first-closing switch and the secondary reclosing of the last-closing switch to realize Switching between first and last.

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