SU432632A1 - DEVICE FOR RELAY PROTECTION OF THREE-PHASE ELECTRICAL TRANSMISSION LINES - Google Patents

Description

iiJoGpcTC.Hiio refers to the oolast of the relay protection L1; n :: 1 transmission of supervic 1 .. o:; o and the base station and is intended to be used for 1: wavelength lines.

A device is known for relaysGG of a three-phase transmission line, consisting of installed at its ends and connected by a channel of a link: 1 transmissions of a blocking signal block: 0x.1} x spgnalovkolko-Mplsktstsv records, each of which contains KJT start-up unit, control unit of the transmitter .com. and forms; RSA; 1i disabling si n :: la, predredchshsh-; i; receiver.

 in 1: a known device with a closure ;: p on a half-wavy LPNPP currents to the left and ci; pn3a from the place of damage to the iio phase, resulting in a total current in place of a short circuit may 3p: j4eH, i.e. : g:;. The pair; the meters of the day off and the dead are determined; the magnitude of the pebalapse, which depend not only on the errors of the measuring transformers and on the types of filters, but also on the efficiency of the model line, the distortion of information when transmitting it to the infrastructure, the foamness of the L, L, B, C, D parameters. The currents ia, n: r} 1 and the unbalance can, as a result, achieve considerable grandeur and cause} ech sun1.1g} 1ness on either side

from the middle of l: 1) 1in. The wellness of this zone can significantly exceed ± 300 km.

In order to increase sensitivity :; h;

the shields in the proposed unit and the trigger ;; the block contains the organs for measuring the relation; absolute values} 1p of reverse currents "OI, l and 1 zero; special connection" Oil ,, L1; n ;; and to the sum m absol OT; YH values of the currents of the domain olegg Vatol; ; the rest of all (kta. | bn) x adjacent prisoy. ;; 1ne; Nd. the organ of the war; beyond 1P1 absolute Zg acchpi is strained; 1 o6ji; Tnoa is consistent: ;; a i :: - :: ax. separated from a secured one; 1 and 11 by one cost of a transfyrumip 1, with an absolute: from 1: an accessory voltage of the same sequence; Nostn on P1; NII OS. ); the default switch is a .uniui 11PV adjacent to the one that is logged: logs: “Ib. "ILTs11" NOT,; oslodn; 1Y; p11 connected to opraiiaM "IT and, moreover, it is forbidden; 1 The last year is united to the first outlet of the organ “IO, the second output of which is connected to the input of the tractor; i to one.

from the inputs of s.TCMeiiTa "P, the second input is kg / tog; the first connection1; nonb: to the output about; thgana" OS, and the input is from the output; ent-hILP connects with the element ale; that “NOT, 15th flow e.1e: c1ma“ OR Comm: 1e; h s: ind moves; Mchatsra

L1PV P element -.I.

FIG. 1 shows a diagram of the electrical connections of the substation, from the tires of the higher engineering which is a waste; it is protected, and the line is; in fig. 2 is a diagram of the formation of comparable magnitudes; in fig. 3 is a schematic diagram of the proposed device relay, and ity lines of electrical radiation.

The proposed device contains transformers / -4 current, voltage transformers 5-6, switches 7-12, current / l per lash, line to be searched, currents / 2 / /, 3; reverse sequence, filters 17 and 18 and reverse sequence charging, rectifying devices 19-28, transreactor 29, starting block 30, transmitter 31, receiver 32, block 33 of controlling the transmitter and forming a tripping spgnal, org and 34 of giving the command pa switching on lnnnn, executive body 35, starting body 36 zlchspty thorn, shut off py blo 37, reverse sequence sequence measurement organ 38, zero-sequence current measurement organ 39, zero-reverse voltage comparison organ 40, logical AND 41-42, logical element ILAR1 43, logical 44e46 . Indicator 47 is the position of the switches of the lines adjacent to, the interlocking device 48 (igr1PoM11On the device 49), the indicator 50 of the one-sided switching on lnpi and the oprai of the control 51 are directly on the lpnpp.

The starter unit has a 3S and 39 current measuring organs, reacting O 1 1e corresponding to a reverse zero follower current, since the hygro-wavelength electrical circuits are characterized by 1 type of zones, in addition to the middle one, which are short to the ground, where the component current is whether the sequence can be close to 0.

Comparison body 40 is used to ensure the selectivity of short circuits at point s / Cs (php. 1) in the mode when power line 1 is off and). Compared currents on line damage, compare the absolute of the first voltage values reverse sequence at the place of CONNECTION 1I of line t. G in

place separated from. lines in one step transformation. i.e. for t / 2H autotransformers. To increase the sensitivity of the organ 30, the voltage at the point of connection of the line is a lump, which is then drawn to the KOL sequence.

Depending on the mode of operation, the iodustan signal from the stroke of the current measuring element 38 is fed to the input of the logic element ПЛГ1 43, or via switch 47 of the position of the line switches. from the protected one, skip the start of the start, if at least one line is turned on, from which there is a make-up, or through the logical element "AND 41, and the second input of which

The signal from the organ 40 is compared. The signal at the output of the logic element "And 41 appears and the presence of signals at its two inputs, i.e., the organs 38 (40) are simultaneously triggered. At the second input of the logical element" ILP 43 a signal is received from the current measuring element 39. At the logical element "OR 43, a signal appears and a signal is received at least one input.

To prevent malfunctioning of the short circuit at the point Kz and trigger the van and current measurement of the body, the zero sequence action of this body when the current is negative and the reverse sequence is forbidden using the logic element HE 44 and the signal is NOT valid. is fed from the output of the current measuring element of the reverse sequence, regardless of the ratio of the compared values. The reliable blocking of the measuring unit of the zero sequence is ensured by the fact that the external short circuit has a negative sequence current; it is much larger than the zero sequence current.

From the output of the logical element “OR 43 C), 1 gngl is set to the following: Transmitter 31 and through the organ 48 to the input of the logical element I 42, to another input of which receives a signal from the receiver 32 receiving the current signal. From the output of the logic element "And 42, the signal is set to; the answeral signal is 35, disconnecting 0 tsyp. Transmitter 31 transmits a second signal to the other end of the line.

When KopoTiKOM closure on the studs can work as a current measuring body of the reverse sequence, as well as a voltage measuring device. At the same time on the prototype. The transmitter is installed. Incorrect operation of the protection is prevented in this case with the help of the logistic elements HE 45 and 46, which do not allow the sigal to exit the logic element P1LI 43 when a signal is received from the starting device 36 tires. If the current measuring unit is closed on the i.x. i.e., i.e., the prohibition of the protection from the busbar start protection device can be reduced by disconnecting the block 37.

When a short ayamkani is on the left 3 of its one-sided mode, when the line is turned on for a short circuit; An emitter mounted on a global hemisphere does not get stuck. In order to ensure the operation in these cases, its work is envisaged in the absence of authorizing this: with the opposite of the KOiiua line through -; id1n ator 50.

To prevent false operation of ZUHTb at the expense of the switching times of the phases of the switch at the subsequent switching on of the line, and from the other end it is planned to transmit a blocking signal from there, which is carried out as follows. When the line is switched on from the supply organ 34 through the voltage control organ 51, the signal lia receives the lia signal, the indicator 50 of the one-sided switching on the line, which then goes into another state and passes the signal from the output of the logical element HE 45 to the secondary authority 35. At the same time, a signal is sent to the transmitter, which sends to the opposite end of the line a short-term blocking signal, which translates the indicator 50 at the opposite end to a state in which it does not pass the signal to the exciter ny authority. When the line is switched on from the other end, the receiver sends a blocking signal and sends a pulse to the indicator 50, after which the protection works only through the logical element "And 42. The control body 51 controls the presence of voltage on the line and passes the signal to the isolator 50 only tension In order to prevent a false operation of the protection when the line is turned on, the voltage being iodine, due to the different times of switching the phases of the switch before, a slowdown of the operation of the sensor is seen with the help of a signal from the command 34 for switching on the logical elements PE 45 and 46. this signal is memorized by the device 49. memory for the time necessary to reliably block the protection; The coupler 49 delays the protection action when the line is turned on for a short circuit. In order to accelerate line disconnection, non-selective protection is briefly introduced (a relatively small stretch is used for power lines). In the event of a swing of TOKOBi ie, the measuring organs may operate under the influence of large unbalance currents. In order to prevent false operation, the signal from the output of the logical element OR 43 is output to the output of the logic element of the AND 42 through the swing lock body 48, which is a device that reacts, for example, to the rate of change of the vector currents of the reverse and zero sequences. In case of asymmetrical short circuits on the protected line connected on both sides, the lockout element 48 is triggered, as well as the current measuring body 38 of the reverse sequence 39 and the slide body 40: P1 or more measuring or current measuring body of the 39 G1 mevsp sequence. From the outputs of the bodies 55, 40 and 39, through the switch position 47 of the switches or through the logical element "AND 41 and through the logical element" PE 44, respectively, signals are received to the two inputs of the logical element "OR 43, from the output of which through the logical element" PE 46 a signal is received at the start of the transmitter, which transmits the enabling signal to the opposite end of the line, and through the logical element "PE 45 and the blocking body 48 when the pumper moves, it sends a signal to the logical element" 1Ь 42. Receiver 32 receives the enabling signal from the half-set, on the other end of the terminal, and sends a signal to the second input of the logic element "And 42. From the last output, the signal goes to the executive authority, which carries out the disconnection of the line. With symmetrical short-circuits, under-response reacts to a short-term asymmetry. In this case, the current measuring units and the voltage comparison unit are made with the minimization of the compared values for the time required to disconnect the line during a short circuit. Subject and connection Device for relay protection of three-phase power transmission line, which are installed at their ends li. the control unit of the transmitter and the formation of a tripping signal connected to the output of the starting block, due to the fact that, in order to increase the sensitivity, the starting block contains organs of absolute magnitude Reverse current "OI2 p zero sequence" OPT line to the sum of the absolute values of the currents of the same sequence of all other adjacent connections, the organ comparing the absolute value of the reverse sequence voltage on the tires, separated from the protected one line by one step of transformation, with the absolute value of KO I pensi the same sequence of the pa lines of the “OS, the indicator of the switch K1-: the switches of the lines“ PPV adjacent to the protected one, the logical elements “1b,“ OR, “NOT, the last connection N to the bodies of "OIO and" OI2, and the prohibiting the entrance of the latter is connected to the first exit of the authority "OIO, the second output of which is connected to the input of the indicator" TID n to the inputs of the element "I, the second ACI of which is assigned to the output of the authority" OS element element, -: IL11 is connected to the output of ELS :. “NOT, the second input of the element“ OR is connected to the outputs of the indicator “IPV and element“ I.

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