SU1432650A1 - Arrangement for protecting against current leaks in mine electric locomotive contact-wire network - Google Patents

Description

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Pejitc FIG.

; The invention relates to the field of relay protection and is intended to disable the contact network of the electrical emergency pumping system when a dangerous current leakage occurs in the network.

Cel, the invention is to improve the accuracy of operation of the SCHITCHA.

Figure 1 presents the block diagram of the proposed device} ia figure 2 - the position of the working frequency of the device on the amp} and the phase and frequency characteristics of the electric locomotive,

The device contains a high-frequency 1 and low-frequency 2 generator of rhinocelerating voltage, the first 3 and second 4 multipliers of signals, the phase shifter 5, the operating current sensor 6, the low-pass filter 7 (low-pass filter relay element 8, the switching unit 9 V of the power unit

10 and traction engines 11 elektrovo; call included respectively feeder

12 and 13 electric locomotive fence, which are parallel resonant circuits

The multiplier of 3 signals, multiplying the sinusoidal voltages, arriving from the high-frequency 1 and low-frequency 2 generators, forms a two-frequency operational voltage with frequencies, w, Wg + W | (where Wg is the generator frequency 1, w is the frequency of the generator 2), which is fed into the | contactnuk1 network - one output section of the HF 3 through the separation capacitor 14 is connected to the contact wire, and the other is connected to the rail. To load the contact network - t govye engines

11 electric locomotives and the power supply unit 10 did not short-circuit the source of operational voltage (output of multiplier 3), they were processed by electric locomotive 13 and feeder 12 by barriers, respectively. Moreover, locomotive barriers 13 are configured in such a way that the operating frequencies

W, and w lie on the inductive branch of their amplitude-frequency characteristics. The demodulation of the two-frequency operating current in the network, measured by sensor 6, is performed by a three-input multiplier of 4 signals and connected to its output of low-pass filter 7. In order to ensure in the measuring organ zshtsity compensation of passive interference from the flow of operational current

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Cut electrically 11) 1e iggeli load, nei-ie-multiplier 4 imglsstll Eggs multiply the two-frequency operating current signal from sensor 6 by voltage, with Bf oscillator 1 and voltage from low frequency oscillator 2, delayed by phase shifter 5 by the value of switching angle Cf. The relay element 8, which sets the setpoint for the operation of the protection device, is connected to the output of the low-pass filter 7 and controls the operation of the switching device 9. The components of the operating current flow through the current sensor 6 through the electric locomotive barrier 13, the conduction of the contact network and dangerous leakage The component of the operational current flowing through the electric locomotive barrier 13 does not give a significant disturbance to the output of the measuring element (at the output of the low-pass filter 7), since the known mechanism for compensating passive interference in the meter th body dual-channel protection. When electric locomotives are removed to the end of the protected part of the network, the components of the output signal of the low-pass filter 7 obtained by detection at frequencies v and w are approximately equal in magnitude and opposite in sign, and passive interference at the output of the low-pass filter 7 determines the sum of the components through the control channels turns out to be not so significant. The component of the operating current, caused by the conduction of the contact network, gives the output of the low-pass filter 7 an initial voltage, which is eliminated when the latter is operated as a twin-current relay by applying a reverse polarity compensating voltage to the second winding. The occurrence of a dangerous leakage in the network (accidental contact of a person with a contact wire or a concentrated fire leak) causes a corresponding voltage at the output of the LPF 7, if the threshold element 8 is exceeded, the relay element 8 removes the supply voltage from the contact network unit 10,

When Vcod voltage generators high frequency 1 and low frequency 2

bv, (t) u,

Cos w t,

I 1432650

Ur (t) U. cos, + cos (we + WH), - cos (w, t + tp), - where Ug, Up, are the amplitude values of U cosCw t- (f). (2); voltages, output voltage

The signal multiplier 3 extracts a constant component of the output signal. The multipliers (t) K and (t) U (t) form the components of the same when the pair B is multiplied .... g f -. .-. output frequencies of signals (1) and (2)

 Tj- K- -UB-i., Cos (Wft-wJt + 10 / V /

2 PS in and L 6 n frequencies w,:

+ COS (W + W) t and cos W-t + UuCOS W-t, „r.,.„.,.

About J 1 M a cos w, t + B, -cos (w, t + 90 JJ

where K ... is the scale factor ,. f 1 „„ G /

., cos (w. t + cpj K. -and -G cos (-tf.,) +

multiplier; t5 2 AT i L

. 1-ill

U 2- Ug U - amplitude + cos (2w, t + q) J + y, B,

sinusoidal voltages / „

with frequencies w, and w.

X cos (90 ° -q) + cos (2w, t + ((i +90)

With network conductivity at frequencies of 20 12 g / o.,.

 - K., U .. G. cosq .. + cos (2w, t + tfj.) +

w, and w ,. respectively2 A MIL -i to -ic j

Y ,, G. -.JB ,, i ,, G, -HJB ,, -K, .u; .B, sincf, -sin (2w, t.f,);

„-Jc frequency

where G ,, Gj are the active constituents;

Bi, B. - reactive components „„ g, l g, / h

 K-T- U .. G.-COS w, t + B. Cos (w, t + 90) if

network conductivity, on-ATMLJ 22 5

Output time dat- ",, 1" "2" g

current 6, corresponding to U -cos (w, t-Cf,) .G, coscf, +

which proceeds through 30 / g, L 1,,

its operating current cos (2w, t-q,) J -n- K. and, .B, with

networks) .- (90% Cf) + cos (2wjt-lf +90)

U. (t) K ,,. I, (t), K ,,. U.G, cosw.t., cos ,,. Cos (2w, t-4 ,,).

+ B, .w, (w,) + G, .cosw, t (1) ,, - sin (|, -sin (2w, t-cp4.

ABOUT

, 0 vH Therefore, the signal is direct current

+ B, .cos (w, t + 90), code. FNC 7

40I, 2

where Kd is the transfer ratio of dates-Ujp (

chika current ..

Output voltage phase shifting- + -j sinq) (B j-Bj) l 5

U ,, (t) U, .cos (w, t-c ,,),, (G ,,). Kp (B, -B,), (3)

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a multiplier of 4K signals from K. U cosq),

Unc (t) KneUre (0 L (t) .U (t)

(to simplify the scale factors - Qcr - K. U sint | |.

multiplier multipliers 3 and 4

same). As seen from (3), the measurement

The result of multiply multiply-circuit dual-channel leakage protection

Lem 4 of the first two signals. current in the proposed embodiment (figure 1)

V tt / .-ch It with “-h -; characterized by control channels

l. ,, .. ig „С / if.С / - JJ ,,

- strictly identical coefficients

 1 TO, . U.-UHfcosRw.-wJt -fCf, sensitivity to active conduct / L LOH J MOSTI and strictly identical in size, -

Wp, i.e. Wp 2

-, and resistance

not, but opposite in sign, sensitivity coefficients to reactive conductivity, which is a necessary condition for the compensation of passive interference in the measuring body of two-channel protection and is achieved in a known device only with a certain accuracy by individual tuning through the control channels.

With inductive tuning of electric locus on both channels (when the operating frequencies w and w lie on the inductive branch of their amplitude-frequency characteristics), the resistance of the isolators at frequencies w and W is active-inductive and the inductance of the line L, when electric locomotives are removed in The end of the protected network section acts in the same way on both control channels, increasing the impedance to the operating current on both the first and second frequency channels. In contrast to the symmetric setting of electric locomotives in a known device (when the operating frequencies w, and w, lie symmetrically with respect to the resonant frequency of the protectors - w

The barriers at the frequency w are active-inductive, and at the frequency W2 - active-capacitive), the introduction of inductive resistance of the line into the control circuit on the second channel does not approximate, but, as and on the first channel, gives rise to a series resonance in the control circuit , which means, that the line inductance effect causes a smaller difference in the values of the operational currents in the channels and uncompensated interference at the output of the measuring body when removing

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electric locomotives at the end of the section will be less

The transition from the symmetric setting of electric locomotives to inductive ones, by changing the capacitor capacity of the prohibitor, is possible due to the insensitivity of the measuring device of two-channel protection to reactive conductivity.

The advantage of the proposed device in comparison with the known one is a higher accuracy of operation, which makes it possible to increase the operating safety of the contact electric locomotive pumping and reduce the number of false protection and, consequently, reduce the wear of the power switching equipment and interruptions in the work of contact pumping.

Keeping the former (as in the prototype) accuracy of the device, it is possible to reduce the required resonant resistance of the electric arresters, which means reducing the consumption of expensive high-frequency power wires, reducing the size and weight of the barriers.

In addition, it is easier to set up the device during production and operation, since there is no need to set the same amplitude of the generator voltages on both channels, the same values of switching angles and switching voltages, the same transmission coefficients of the phase-sensitive detectors, since the necessary ratios for the sensitivity coefficients of the protection protection circuit To the active and reactive conductance of the MGO two control channels are provided by the very construction principle of the proposed about the device.

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U /; 0/2 (

(jJ

BQ f;

f2

U /; U / 2

.

Claims (1)

DEVICE FOR PROTECTION AGAINST CURRENT LEAKAGE IN THE CONTACT NETWORK OF ELECTRIC ROLL-IN, containing two sinusoidal voltage generators, one of which is high-frequency, an operational current sensor included in the control circuit, a phase shifter, a low-pass filter, the output of which is connected to the input of the relay element acting on the switching element the apparatus, as well as the feeder and electric locomotive frequency chokes, the terminals of which are intended to be connected respectively to the circuits of the power unit and traction motors of electric locomotives, characterized in that, in order to improve the accuracy of operation, two signal multipliers are introduced, one of which is three-input, and the second sinusoidal voltage generator is made low-frequency, while the output of the first sinusoidal voltage generator is connected to the first inputs of both signal multipliers, the output of the second generator is connected to the second the input of the first multiplier directly and through the phase shifter with the second input of the second multiplier, the third input of which is connected to the output of the operational current sensor, Exit first multiplier signals for connection to the trolley line, a second output connected to the input of a lowpass filter, wherein the operating frequencies are located on the control current inductive branch of the amplitude-frequency characteristics of the locomotive suppressors. Rail Fig-1