SU1595710A1 - Measuring member for two-frequency protection from current leaks in contact system of mine electric locomotive haulage - Google Patents

Abstract

This invention relates to relay protection and is intended for use in a dual-frequency leakage protection apparatus. The purpose of the invention is to expand the field of application by allowing it to work in an arbitrary place of the contact network with an arbitrary source of dual-frequency operational voltage. The measuring element contains the sensor 1 operating current, sensor 2 operating voltage, three-input multiplier 3 signals, quad 4, band-pass filter 5 and the phase shifter 6. One input of multiplier 3 is connected to the output of sensor 1, the other with the output of phase shifter 6, and the output with input lowpass filter 7 7. The output of sensor 2 is connected to the third input of multiplier 3 and the input of quad 4, the output of which is connected to the input of phase shifter 6 via filter 5. The measuring element can work efficiently in terms of passive interference compensation an arbitrary location of the contact network with an arbitrary in terms of internal resistance and the ratio of the magnitudes of the operational voltages of the two frequencies of the dual-frequency operational voltage source.

Description

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The invention relates to a relay protection and is intended for use as part of a dual-frequency protection equipment that disconnects the contact network when a dangerous current leakage occurs in it.

The purpose of the invention is to expand the scope.

The drawing shows the proposed measuring body.

The two-frequency measuring unit for GI, G2, is the active and reactive components of BI, which are 62 conducive to conductivities at frequencies;

Ф - phase shift of the phase shifter. As can be seen from this expression for the output signal of the measuring organ, it has the same sensitivity to active conductivity and the same sensitivity in magnitude but opposite in sign to the reaction "J ---- 11 vxvi v Jiiijivy liv kJHUJVy TYUV lDrJl i. Wl DITJV ID rV L / CClfV

; shields FROM leakage current contains a sensor of one-Yu-tive conductivity of the network, which is not: operating current 1, sensor of operational pressure 2, three-input signal multiplier 3, quad 4, band pass filter 5,: phase shifter 6, bottom filter frequency 7; And the executive body (not shown). The operational current sensor 1 is connected in series with the contact network, the operational voltage sensor 2 is connected to the protected network — one input terminal to the contact network, and the other to the rail, a necessary condition for the effective operation of the measuring unit. This condition is fulfilled at any ratios between the magnitudes of the operational voltages of the two frequencies that flow into the measuring body directly from the contact network. From the point of view of the compensation of passive interference, the measuring body can work in the place of the contact network with an arbitrary source.

The strokes of both sensors are connected to two I / O two-frequency operational voltages.

The signal multiplier 3, the third input of which is connected to the output of the phase shifter 6, whose input through the band-pass filter 5 and quadrant 4 is connected to the output of the operating voltage sensor 2. The output of the signal multiplier 3 is connected to the input of the low-pass filter .7 whose output is The output of the measuring organ. In the contact network at the location of the measuring organ, a two-frequency operational voltage acts, which causes an operational current flowing in the network, determined by the complex resistance of the network, the output voltage of the sensor voltage 2 contains both frequencies. The output voltage of the quadrant 4 contains a component of the difference frequency, which is injected by the usb filter 5. Its output signal through the phase shifter 6 is fed to their third signal multiplier 3. Its signal contains a constant component that is separated by a filter low frequencies. Its output voltage is

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that is, a source with arbitrary internal resistance. and the ratio of the magnitudes of the operational voltages of two parts. In addition, it allows to simplify the source of dual-frequency operational voltage, to provide a protective disconnection not of the entire network, but only of its section containing a dangerous leak. It is also possible to promptly check the electric locomotives in an arbitrary place of the contact network, which allows 30 to maintain the accuracy indicators of all protection at a given level.

Claims (1)

Invention Formula 35 40 Measuring body of dual-frequency protection against leakage of current in the contact network of the mine electric locomotive haulage, containing the operating current sensor, three-input signal multiplier, low-pass filter and phase shifter, one input of the signal multiplier is connected to the output of the operating current sensor, the other with the output of the phase shifter, the output multiplier of the signals is connected with an input of a low-pass filter, characterized in that, in order to expand the field of application, an operational voltage sensor, a quad and a band-pass filter are introduced, od operational voltage sensor connected to the third input of the multiplier input signals and the squarer; and the output of the quad is connected to the input of the phase shifter through a band-pass filter. ifn „1 / 4К„ cKgg Kfe (U, Ua) - | {G, 62) sof + -f (B, -Br) 5tf |, where |, and 2 - amplitude values of voltages with frequencies wi and Ш2; , Кдт, К - transfer coefficients of the multiplication, of signals and sensors of operational current and voltage; GI, G2, - active and reactive compounds - BI, 62 luyuschie conductivities at frequencies; Ф - phase shift of the phase shifter. As can be seen from this expression for the output signal of the measuring organ, it has the same sensitivity to active conductivity and the same in magnitude, but opposite in sign, sensitivity to reaction vxvi v Jiiijivy liv kJHUJVy TYUV lDrJl i.Wl DITJV ID rV L / CClfV at two working frequencies network conductivity, which is an inaccurate network conductivity, which is a prerequisite for the effective operation of the measuring body. This condition is fulfilled at any ratios between the magnitudes of the operational voltages of the two frequencies that flow into the measuring body directly from the contact network. From the point of view of the compensation of passive interference, the measuring body can work in the place of the contact network with an arbitrary source. dual frequency operational voltage. dual frequency operational voltage. that is, a source with arbitrary internal resistance. and the ratio of the magnitudes of the operational voltages of two parts. In addition, it allows to simplify the source of dual-frequency operational voltage, to provide a protective shutdown not of the entire network, but only of its section containing a dangerous leak. It is also possible to promptly check the electric locomotives in an arbitrary place of the contact network, which allows you to maintain the accuracy of all protection at a given level. Invention Formula five 0 with Measuring body of dual-frequency protection against leakage of current in the contact network of the mine electric locomotive haulage, containing the operating current sensor, three-input signal multiplier, low-pass filter and phase shifter, one input of the signal multiplier is connected to the output of the operating current sensor, the other with the output of the phase shifter, the output multiplier of the signals is connected with an input of a low-pass filter, characterized in that, in order to expand the field of application, an operational voltage sensor, a quad and a band-pass filter are introduced, od operational voltage sensor connected to the third input of the multiplier input signals and the squarer; and the output of the quad is connected to the input of the phase shifter through a band-pass filter.