CN1082261A

CN1082261A - Make the single-pole reclosing of criterion with non-full phase voltage

Info

Publication number: CN1082261A
Application number: CN 93106704
Authority: CN
Inventors: 李养善
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-05-31
Filing date: 1993-05-31
Publication date: 1994-02-16

Abstract

The invention provides a kind of new method that realizes the single phase autoreclosing of extra high voltage network, method by the induced voltage amplitude of measuring the fault disconnection phase in the non-full phase process, determined that before the reclosing pulse is sent fault disconnects the state of insulation of phase, just overlap when only being judged to transient fault; In order to guarantee be in operation for some reason self-locking or still can make the bilateral successful reclosing when withdrawing from of above-mentioned either side measuring system, do not establish a special distant place and overlap the command channel, and with circuit residual voltage 3U in the non-full phase process of measurement ₀The method of amplitude realizes overlapping in succession, has improved reliability and has used flexibility.

Description

Make the single-pole reclosing of criterion with non-full phase voltage

The present invention relates to a kind of extra high voltage network automatic control equipment, especially a kind ofly react the single-pole reclosing device that line side fault in the non-full phase process disconnects phase voltage and line zero sequence voltage.

Existing single-pole reclosing device all is when circuit generation single phase ground fault, by protective relaying device with circuit after both sides excisions fault, through a certain constant time lag, the state of insulation that fault is disconnected phase is not done any detection and is just sent the reclosing pulse.The CCH type composite auto-reclosing device of Nanjing Automation Inst., Ministry of Electric Power's development, its single-pole reclosing have partly adopted the method for " inspection circuit three-phase has ballast to close ", have solved single-phase back and have overlapped side superimposed in the problem of permanent fault.More than existing single-pole reclosing technology all can not avoid coinciding with permanent fault, not only makes electrical network bear short-circuit impact more, and the equipment of electric power system, and especially large-scale system interconnection transformer and Generator Set etc. reduce useful life because of repeatedly impacting.

The objective of the invention is fundamentally to solve the problem that single-pole reclosing coincides with permanent fault, only when transient fault, guarantee that reliably both sides all want successful reclosing and shorten the single-pole reclosing time as far as possible, recover power system stability as early as possible and move.

One of main points of the present invention are to measure the amplitude that line side fault in the non-full phase process disconnects phase voltage, if during more than or equal to the recovery voltage lower limit, send the coincidence control impuls, if during less than permanent fault phase-ground voltage limiting value, and locking reclosing then; Two of main points are the residual voltage 3Uo that measure in the non-full phase process, when its amplitude is low value, sends and overlap control impuls in succession, and when guaranteeing transient fault really, as long as either side elder generation successful reclosing, opposite side successful reclosing in succession then; When its amplitude is the high value, does not then send and overlap control impuls in succession, reliable locking reclosing.

Below in conjunction with accompanying drawing the present invention is further described.

Fig. 1 is for A being the open-phase operation circuit of fault disconnection phase and the configuration schematic diagram of making the single-pole reclosing of criterion with non-full phase voltage mutually.

Fig. 2 disconnects phase voltage monitoring system GDJS master block diagram for fault.

Fig. 3 is non-full phase condition line trackside residual voltage 3Uo observation circuit FLJD master block diagram.

It is the open-phase operation circuit that fault disconnects phase mutually that Fig. 1 illustrates with A.Although this moment, A phase circuit was separated from electrical network, but owing to perfect the coupling of phase (B, C phase) voltage by alternate electric capacity and perfect mutually of the induction of (B, C phase) load current by alternate mutual inductance, respectively fault is disconnected and produce the auxiliary voltage component mutually, the phasor of the two and represent with Ur, be called recovery voltage, directly influence fault and disconnect the recovery of phase fault nidus insulation and extinguishing of secondary arc current.In order to improve the effect of single phase autoreclosing, usually extra high voltage network is taked wiring shunt reactor and neutral point arc-suppression reactor thereof after, recovery voltage Ur obviously reduces.For example, 500KV system voltage mutual inductor ratio is 5000 o'clock, and two sub-values of Ur can be controlled at (5-10) volt, and for transient fault, after the insulation of fault place was restored, this voltage disconnected phase voltage instrument transformer secondary side from fault and can measure; If permanent fault, for example, during circuit one side outlet Single Phase Metal short circuit, the fault disconnection voltage of this side mutually is clamped at zero volt, and offside voltage via line convergence zero volt, these voltage two sub-values also can disconnect phase voltage instrument transformer secondary side from fault and measure.Therefore, can determine the character of single-phase fault, disconnect phase monitoring system GDJS thereby can constitute the fault that both sides overlap simultaneously or successively overlap by the method for measuring fault disconnection phase voltage; But, when one of this monitoring system self-locking for some reason in service or out of service when meeting single-phase transient fault, can only cause one-sided coincidence and finally make both sides three-phase tripping operation by protective device because of checking, fail from the whole structure single-pole reclosing.In order to guarantee still to make under the above-mentioned situation both sides can both successful reclosing, the present invention be provided with the observation circuit FLJD of residual voltage 3Uo in the non-full phase process of reaction simultaneously, and it has the offside of transmission successful reclosing informational function, thereby realizes overlapping in succession.

Fig. 2 illustrates the fault phase voltage monitoring system GDJS master block diagram among the present invention, and wherein 1 is analog quantity voltage current acquisition system cells D AS; 2 are fault disconnection phase voltage monitoring system logical block GDJL; 3 is switching value input unit SRK; 4 is single-pole reclosing control unit RCC1.Work as single phase ground fault, behind the circuit breaker trip of both sides, the fault disconnection is surveyed voltage mutually and is satisfied

|UΦd|＜UΦg （1）

The time, then fault disconnects the corresponding permanent fault that is judged to, and adjusts time-delay Td both sides reclosing control unit RCC1 with its reclosing block through single-pole reclosing.U Φ d is the induced voltage that fault disconnects phase in the formula; U Φ g is that fault disconnects the phase-ground voltage limiting value when having earth fault mutually, determines by calculating.Surveying voltage mutually when the fault disconnection satisfies

|UΦd|≥UΦrmin （2）

The time, then fault disconnects the corresponding transient fault that is judged to, can send the coincidence control impuls by reclosing control unit RCC1 to CLO1 through the single-pole reclosing time-delay Td that adjusts, U Φ rmin can be by calculating or the actual measurement decision for disconnect the minimum restoring voltage of phase for fault under the non-full phase state in the formula.For circuit through transposition, above-mentioned voltage and separate irrelevant.Usually, extra high voltage network all excises fault, the time-delay of adjusting of single-pole reclosing by the protection of vertical difference principle

Td＝tx+tyd （3）

Tx is the limit extinguishing arc time in the formula, and tyd is the nargin time.In fact, the extinguishing arc time is relevant with insulation status, wind speed and the compensation situation etc. at short circuit current size, fault place, and randomness is very big.If power system stability requires to shorten non-full phase as far as possible during the time, can be under the condition that satisfies formula (2), even the no show single-pole reclosing time-delay Td that adjusts still also can send the coincidence control impuls by reclosing control unit RCC1 to CLO1 in advance.Input analog amount i(t among Fig. 2) is expressed as A, B, C phase current; U(t) be expressed as A, B, C phase voltage; Input switch amount TGJ is A, B, the C fixed relay normal opened contact that trips mutually, with i(t) and TGJ introduce and help reclosing function expansion and perfect.

Fig. 3 shows zero sequence voltage detection circuit master block diagram FLJD in the non-full phase process.5 are conversion rectification filtering unit LBZL among Fig. 3, and 6 is amplitude comparing unit ABP, and 7 is single-pole reclosing control unit RCC2.When circuit both sides fault phase circuit breaker all disconnects, | 3Uo| 〉=100 volt (high value), both sides reclosing control unit RCC2 is with its reclosing block; Overlap side superimposed in the ban when permanent fault, no matter this side relaying protection carries out three links to jump and still still jumps the fault phase, | 3Uo| 〉=100 volt (the high value), offside is still with reclosing block; Have only when overlapping the side superimposed success in the ban, the both sides voltage transformer is by one-sided three phase supply, then | 3Uo|≤10 volt (low value), amplitude comparing unit ABP output state changes, cause offside single-pole reclosing control unit RCC2 to send the coincidence control impuls, and circuit breaker overlapped to CLO2, be equivalent to side superimposed success back with transmission line this as passage, send a distant place to offside and overlap command signal, thus the reliability and the flexibility that have improved single-pole reclosing.

Implementation method of the present invention can adopt silent oscillation or numeric type, also can adopt the pattern of both dual-purposes, to satisfy the use needs of different user.

Claims

1, the non-full phase voltage of a kind of usefulness is made the single-pole reclosing of criterion, comprise that fault disconnects phase voltage monitoring judgement system and the non-full residual voltage of circuit mutually observation circuit, it is characterized in that, before circuit breaker coincidence control impuls is sent, by non-full phase process being broken the judgement of phase voltage amplitude, determine the character of fault, when only confirming as transient fault, just send the coincidence control impuls or overlap control impuls in succession, as long as side superimposed success does not need a special distant place to overlap order transmission passage, after offside residual voltage amplitude judgement affirmation, almost send simultaneously and overlap control impuls in succession, if during permanent fault, the both sides reclosing is by reliable locking.

2, the non-full phase voltage of usefulness according to claim 1 is made the single-pole reclosing of criterion, it is characterized in that, the input variable of its non-full phase residual voltage observation circuit is directly taken from the residual voltage output of line voltage distribution instrument transformer, zero sequence voltage detection circuit is cooperated with transmission line itself constitute distant place coincidence order transfer system.

3, the non-full phase voltage of usefulness according to claim 1 is made the single-pole reclosing of criterion, it is characterized in that, and its single-pole reclosing time, can fix, also can and change according to fault disconnection phase insulation recovery situation.

4, the non-full phase voltage of usefulness according to claim 1 is made the single-pole reclosing of criterion, it is characterized in that, the method for realization of making the single-pole reclosing of criterion with non-full phase voltage can adopt silent oscillation or numeric type, also can two kinds patterns simultaneously and use.