RU2002369C1 - Device for formation of currents of signals in electric power line - Google Patents

Abstract

Usage: in electrical engineering when transmitting information over electrical networks without their special high-frequency processing. Advantageously, the invention is intended for transmitting television signals over distribution networks of (0.38-10-35) kV. The inventive device contains two inductors 1, 5, three capacitors 2, 9, 11, a diode bridge 3, two resistors 10, 12, a signal pin 6, three diodes 4, 7, 8. The first output of the diode bridge is connected to the first output the second inductor with the cathodes of the first and third diodes, the anode of the first diode is connected to the second output of the second inductor and the first output of the signal contact, the anode of the second diode is connected to the second output of the diode bridge, and the cathode of the second diode is connected to the anode of the third diode, the second condensate p and the first resistor are connected in parallel and connected between the second input of the diode bridge and the second phase of the power line, the third capacitor and the second resistor are connected in parallel and connected between the cathode of the second diode and the second phase of the power line. The purpose of the invention is to increase reliability when creating signal currents in a 0.38 / 10 kV power line with the achievement of a technical result - self-healing of a device circuit under emergency conditions.

Description

The invention relates to the field of electrical engineering and may find application in the transmission of information over electrical networks without their special high-frequency processing. Advantageously, the invention is intended for transmitting television signals over distribution networks of (0.38-10-35) kV.

Closest to the proposed technical solution is a device for transmitting signals via a three-phase power line, the transmitting unit of which is adopted as a prototype. In this device, signal currents are introduced into the power line in a passive-active manner, which drastically reduces the power consumption of the transmitter compared to the known device. This is due to the lack of a conventional transmitter power supply, since the transmitter in the prototype is connected directly to the power line. However, the transmitting unit of the known device, adopted for the prototype, has low reliability due to the fact that if the signal contact does not open for any reason at a given point in time, an overload current that exceeds the signal current will flow through its contacts. This will cause the fuses to blow and the device will fail.

The invention solves the problem of improving reliability when creating signal currents in a 0.38 / 10 kV power line with the achievement of a technical result — self-healing of a device circuit in emergency conditions.

In the proposed device, as in the prototype, there is a first inductor, a first capacitor, a diode bridge and a signal contact. The first terminal of the first inductor is connected (through a fuse) to the first phase of the power line, and the second terminal of this coil is connected to the first lining of the first capacitor and to the first input of the diode bridge. The second lining of the first capacitor is connected to the second phase of the power line. The second output of the signal contact is connected to the second output of the diode bridge.

The first, second and third diodes, the second inductor, the second and third capacitors, the first and second resistors are newly introduced. The cathode of the first diode is connected to the cathode of the third diode, with the first output of the second inductor and with the first output of the diode bridge. The anode of the first diode is connected to the first terminal of the signal contact and to the second terminal of the second inductor. The anode of the second diode is connected to the second output of the signal contact and to the second output of the diode bridge, and its cathode is connected to the anode of the third diode. The second capacitor and the first resistor are interconnected in parallel and connected on one side to the second plate of the first capacitor and to the second phase of the power line on one side and to the second input of the diode bridge on the other side. The third capacitor and the second resistor are interconnected in parallel and connected to the second phase of the power line with one

5 sides and to the cathode of the second diode and the anode of the third diode - on the other.

The achievement of the technical result is achieved by reducing the overload current due to the charging of the second capacitor with a current frequency of 50 Hz.

The drawing shows a schematic diagram of the proposed device.

A device for generating signal currents in a power line contains a first 5 inductor 1, a first capacitor 2, a diode bridge 3, a first diode 4, a second inductor 5, a signal contact 6, a second diode 7, a third diode 8, a second capacitor 9, a first resonator side 10, third capacitor 11, second resistor .12.

The first output of the first inductor 1 is connected through a fuse (not shown) to the first phase

5 (phase 1) of the power line, the second terminal of this coil is connected to the first plate of the first capacitor 2 and to the first input of the diode bridge 3. The first terminal of the diode bridge 3 is connected to the cathode of the first

0 of the diode 4 and the first output of the second inductor 5, the second output of which is connected to the first output of the signal contact 6. The second output of the signal contact b is connected to the anode of the second diode 7 and c

5 by the second output of the diode bridge 3. The cathode of the second diode 7 is connected to the anode of the third diode 8, the cathode of which is connected to the first output of the second inductor 5. The second capacitor 9 and the first resistor 10

0 are interconnected in parallel and connected to the second lining of the first capacitor 2 and the second phase (phase 2) of the power line on the one hand and to the second input of the diode bridge 3 on the other hand,

5 The third capacitor 11 and the second resistor 12 are interconnected in parallel and connected to the second phase (phase 2) of the power line on the one hand and to the cathode of the second diode 7 and the anode of the third diode 8 on the other hand.

The device operates as follows.

Normal mode The signal contact 4 is closed in the interval Au, and

A-t-to

Ati -x-

1

where To is the period of closing (opening) of the signal contact 4; fo - signal frequency. ,

Let the potential of the first phase of the power line (phase 1) be higher than the potential of the second phase of the power line (phase 2). The signal current along two circuits is introduced into the power line.

Primary circuit: phase 1 — first inductor 1 — diode bridge 3, second inductor 5, signal contact 6 — diode bridge 3, second capacitor 9 — phase 2 (elements of the first circuit are selected from the condition

fo

1

(2)

V (Li + L5) Ce

where Li is the inductance of the first inductor 1;

Ls is the inductance of the second coil 5;

Ce is the capacity of the second capacitor 9.

Second circuit: phase 1 - first inductor 1 - diode bridge 3 - second inductor 5, signal contact 6 - second diode 7, third capacitor 11 - phase 2.

At the moment of opening the signal contact 6 of the first, the inductor 1 accumulated electromagnetic energy and free oscillations with frequency fo will occur in the phase 1 - first capacitor 2 - phase 2 circuit. Elements of this circuit are selected from the condition

fo

1

(3)

2jrV LiC2

where C2 is the capacitance of the first capacitor 2.

After a period of time At2, the signal contact b closes again. Moreover

Zto

3

: tg0 (4)

Thus, in the time interval 0.25To, the signal contact 6 is closed, and in the time interval 0.75To - open. Capacitor 11, second and third diodes 7 and

8 serve to transfer reactive energy to the power line through the circuit: phase 2 - third capacitor 11 - third diode 8 - second inductor 5 - signal contact 6 - diode bridge 3 - first inductor 1 - phase 1. The second inductor 5 serves limit the discharge current of the first capacitor 2 through the signal contact 6 at the beginning

operation of the device when the first capacitor 2 is charged, as shown in the drawing. At the moments of the closure of signal contact 6, a current will flow through it through the circuit: first capacitor 2 - diode bridge 3 - second inductor 5 - signal contact 6 - diode bridge 3 - second capacitor 9.

The reverse first diode 4 serves to remove overvoltages from the signal contact 6 at the moment of its opening, caused by the stored energy of the second inductor 5.

If the potential of phase 2 is higher than the potential of phase 1, the signal current will go from phase 2 to phase 1 with the closed state of signal contact 6. Emergency mode,

After some time Ati 0.25To, for some reason, the signal contact 6 did not open (in the absence of control pulses for short circuit). This situation is possible when a semiconductor element is used as signal contact 6. If the potential of phase 1 is higher than the potential of phase 2, then through the signal

the contact will go a current of frequency 50 Hz and charge the capacitor 9 and 11 with the polarity indicated in the drawing. When the charge of these capacitors reaches the amplitude value of the voltage of the supply voltage applied to phases 1 and 2, the current through signal contact b will be zero. If there are no control pulses to close the signal contact 6, it will open.

The device will again be ready for operation after a period of time DGZ. Moreover

At3 3RioC9-3Ri2Cn, (5) where Ac3 is the discharge time of the second and third capacitors 9 and 11, respectively, at

first and second resistors 10 and 12;

RIO is the resistance of the first resistor 10;

Ri2 is the resistance of the second resistor 12;

SD - the capacity of the second capacitor 9; C is the capacity of the third capacitor 11.

(56) Copyright certificate of the USSR Ns 1107750, cl. H 04 B 3/54, 1984.

Claims (1)

SUMMARY OF THE INVENTION -capacitors, two resistors, the first DEVICE FOR CREATING A TO-stroke of the diode bridge is connected to the first SIGNAL OUTPUT in the ELECTRON line by the water of the second inductor and from the EDIT containing the first coil in-g cathodes of the first and third diodes, the inductance anode , the first capacitor, the diode of the first diode is connected to the second output bridge and the signal contact, the first second inductor and the first output of the first inductor under the output of the signal contact, the anode is connected to the first phase of the line of the electric diode - with the second output of the diode dacha, the second output to the first output of the bridge, and the cathode of the second diode to the anode of the first capacitor and to the first input of the third diode, the second capacitor and the diode bridge, the second output of the first resistor connected in parallel and the capacitor is connected to the second phase -connected between the second input of the power transmission diode, the second output of the signal bridge and the second phase of the electronic contact line is connected to the second transmission15, the third capacitor and the second output of the diode bridge, a different resistor are connected to and sub-parallel to that has been entered three diodes, a second key between the cathode of the second diode and an inductor and second transmission lines tretiyvtoroy phase.