CN207281165U - A kind of induced voltage detection device and its control system - Google Patents

Abstract

The utility model discloses an induced voltage detection device, which is characterized in that it comprises a capacitor voltage divider and a peripheral circuit connected with the capacitor voltage divider, and the capacitor voltage divider includes a first capacitor C0 and a second capacitor C1 ; The peripheral circuit includes a signal cable wave impedance Z, a matching resistor R; the first capacitor C0 and the second capacitor C1 are connected in series, and the common end of the first capacitor C0 and the second capacitor C1 is connected to a pin of the input end of the signal cable wave impedance Z Connect, the other pin of the input end of the wave impedance Z of the signal cable is connected with the other end of the second capacitor C1, one pin of the output end of the wave impedance Z of the signal cable is connected with one end of the matching resistor R, and the output end of the wave impedance Z of the signal cable The other pin is connected with the other end of the matching resistor R. In addition, the utility model also discloses an induction voltage control system. By adopting the utility model, the measurement accuracy of the voltage is improved, and the safety performance is improved.

Description

An induced voltage detection device and its control system

technical field

The utility model relates to the technical field of induced voltage, in particular to an induced voltage detection device and a control system thereof.

Background technique

The electromagnetic environment where the substation is located is a power frequency electromagnetic field, which is a quasi-static field. The metal conductor in the electric field makes it to the ground potential through capacitive coupling or electromagnetic coupling, that is, presents the electrostatic induction voltage, electromagnetic induction voltage and ground current to the ground. Taking the parameter test of the double-circuit transmission line on the same tower as an example, the induced voltage on the line is as high as several thousand or even tens of thousand volts during a single-circuit power outage.

The voltage can be as high as several thousand volts. Under this condition, the line parameter test will not only affect the accuracy of the test data, but also cause damage to the test equipment and even threaten the life safety of the test personnel. It can be seen from the power system safety notification materials that there have been cases of casualties caused by induced electricity.

At present, the induction voltage control system usually uses the induction voltage detection device to measure, and the staff judges whether there is a dangerous situation according to the detection results. cause great harm to personal safety.

Utility model content

The purpose of the utility model is to provide an induced voltage detection device and its control system, which improves the safety performance.

In order to solve the problems existing in the prior art, the utility model provides an induced voltage detection device, which includes a capacitive voltage divider and a peripheral circuit connected to the capacitive voltage divider, and the capacitive voltage divider includes a first capacitor C0 and the second capacitor C1; the peripheral circuit includes signal cable wave impedance Z, matching resistor R;

The first capacitor C0 and the second capacitor C1 are connected in series, the common end of the first capacitor C0 and the second capacitor C1 is connected to one pin of the input end of the wave impedance Z of the signal cable, and the other pin of the input end of the wave impedance Z of the signal cable is connected to the electric current. The other end of the second capacitor C1 is connected, one pin of the wave impedance Z output end of the signal cable is connected to one end of the matching resistor R, and the other pin of the wave impedance Z output end of the signal cable is connected to the other end of the matching resistor R.

Preferably, an oscilloscope input resistor R2 and an oscilloscope input capacitor C2 are further included, and the oscilloscope input resistor R2 and the input capacitor C2 are respectively connected in parallel at both ends of the matching resistor R.

Preferably, a compensation resistor R1 is further included, and the compensation resistor R1 is connected in series between the matching resistor R and the input capacitor C2 of the oscilloscope.

Correspondingly, the utility model also provides an induced voltage control system, the system includes an induced voltage detection device, an oscilloscope connected to the induced voltage detection device, and the induced voltage detection device includes a capacitor voltage divider and a voltage divider connected to the capacitor voltage divider Connected peripheral circuits, the capacitive voltage divider includes a first capacitor C0 and a second capacitor C1; the peripheral circuit includes a signal cable wave impedance Z, a matching resistor R;

The first capacitor C0 and the second capacitor C1 are connected in series, the common end of the first capacitor C0 and the second capacitor C1 is connected to one pin of the input end of the wave impedance Z of the signal cable, and the other pin of the input end of the wave impedance Z of the signal cable is connected to the electric current. The other end of the second capacitor C1 is connected, one pin of the wave impedance Z output end of the signal cable is connected to one end of the matching resistor R, and the other pin of the wave impedance Z output end of the signal cable is connected to the other end of the matching resistor R.

Preferably, the induced voltage detection device further includes an oscilloscope input resistor R2 and an oscilloscope input capacitor C2, and the oscilloscope input resistor R2 and the input capacitor C2 are respectively connected in parallel at both ends of the matching resistor R.

Preferably, the induced voltage detection device further includes a compensation resistor R1, and the compensation resistor R1 is connected in series between the matching resistor R and the input capacitor C2 of the oscilloscope.

Preferably, an induction voltage elimination device is also included, one end of the induction voltage elimination device is connected to an oscilloscope, and the other end of the induction voltage elimination device is connected to the circuit to be tested.

Preferably, the oscilloscope includes a receiving unit, a sending unit, a microprocessor, an A/D converter, and a waveform display unit, the input of the receiving unit is connected to the output of the induced voltage detection device, and one of the receiving units The output end is connected with the waveform display unit, the other output end of the receiving unit is connected with the input end of the A/D converter, the output end of the A/D converter is connected with the input end of the microprocessor, and the microprocessor The output terminal is connected to the sending unit.

The induced voltage detection device of the utility model is provided with a capacitive voltage divider, and the detection accuracy of the induced voltage is improved through the arrangement of various components of the peripheral circuit, and the safety is improved.

Description of drawings

Fig. 1 is a schematic diagram of an embodiment of an induced voltage control system of the present invention;

Fig. 2 is a schematic diagram of a circuit principle of an induced voltage detection device of the present invention;

Fig. 3 and Fig. 4 are equivalent schematic diagrams of a circuit principle of an induced voltage detection device of the present invention;

Fig. 5 is a schematic diagram of a detection effect simulation of an induced voltage detection device of the present invention;

Fig. 6 is a schematic diagram of an embodiment of an oscilloscope in an induced voltage control system of the present invention.

Detailed ways

The utility model is described in detail below in conjunction with accompanying drawing.

Referring to Fig. 1, this figure is the schematic diagram of a kind of induced voltage control system of the present utility model, and this system comprises: induced voltage detection device 1, oscilloscope 2, induced voltage eliminating device 3; One end of induced voltage detection device 1 is connected with circuit to be tested , the other end of the induced voltage detection device 1 is connected to one end of the oscilloscope 2, the other end of the oscilloscope 2 is connected to one end of the induced voltage eliminating device 3, and the other end of the induced voltage eliminating device is connected to the circuit to be tested. Therefore, the induced voltage of the line to be tested can be detected by the voltage detection device 1, and then oscillographically displayed by the oscilloscope 2, and the induced voltage in the line to be tested can be eliminated by the induced voltage elimination device connected to the line to be tested, thereby realizing automatic Detect the induced voltage on the construction site and automatically adjust the generated induced voltage, which improves the safety of the construction site.

As shown in FIG. 2 , the induced voltage detection device 1 includes a capacitive voltage divider 11 connected to the circuit to be tested and a peripheral circuit 12 connected to the output end of the capacitive voltage divider 11 . Wherein the capacitive voltage divider 11 includes: the first capacitor C0 and the second capacitor C1; the peripheral circuit 12 includes the signal cable wave impedance Z, the matching resistor R; the first capacitor C0 and the second capacitor C1 are connected in series, the first capacitor C0 and the second capacitor The common end of the capacitor C1 is connected to one pin of the input end of the wave impedance Z of the signal cable, the other pin of the input end of the wave impedance Z of the signal cable is connected to the other end of the second capacitor C1, and one pin of the output end of the wave impedance Z of the signal cable is connected. The pin is connected to one end of the matching resistor R, and the other pin of the wave impedance Z output end of the signal cable is connected to the other end of the matching resistor R.

Among them, C0 and C1 are high-voltage and low-voltage arm capacitors respectively; Z is the wave impedance of the signal cable; R is the terminal matching resistance, and the value is 50 ohms; R1 and C2 are the integral resistance and capacitance respectively; R2 and C are the oscilloscope Input resistance, capacitance. The input resistance R2 of the oscilloscope is much larger than the compensation resistance R1, then the output y(t) of C1 is R, then there is

When (C ₀ +C ₁ )dy(t)/dt>>y(t)/R,

That is u(t)=((C ₀ +C ₁ )/C ₀ )y(t)

The equivalent circuit diagrams are shown in Figure 3 and Figure 4.

In specific implementation, the simulation signal source can be set as follows: initial voltage: 0V, pulse amplitude: 200kv, time delay: 2ns, rise time: 10ns, fall time: 10ns, pulse width: 100ns. When the parameters of the voltage divider are adjusted to Rml=439Ω, L1=1.2pH, Rm2=30Ω, L2=0.12pH, the simulation results are shown in Figure 5, and the results obtained by adjusting the simulation parameters many times are more ideal.

In order to test the accuracy of the induced voltage measuring instrument, a high-voltage electrostatic voltmeter and an induced voltage measuring instrument were used for comparative testing in the measurement of the line parameters of the 110kV Minyan 1292 line. The comparison found that the measurement results of the two are very close, which shows that the type induction The voltage measuring instrument has high test accuracy. The test results are shown in Table 1 below.

Table 1. Measurement results of induced voltage on 110kV transmission line

As shown in FIG. 6 , the oscilloscope 2 includes a receiving unit 21 , an A/D converter 22 , a controller 23 , a waveform display unit 24 and a sending unit 25 . Wherein, the input terminal of the receiving unit 21 is connected with the output terminal of the induced voltage detection device, one output terminal of the receiving unit 21 is connected with the waveform display unit 24, and the other output terminal of the receiving unit 21 is connected with the input terminal of the A/D converter 22 connection, the output end of the A/D converter 22 is connected to the input end of the controller 23 , and the output end of the controller 23 is connected to the sending unit 24 .

Different elimination strategies can be set for the induced voltage elimination device 3 , which will be described in one or two embodiments below. In one embodiment, the induced voltage eliminating device 3 is provided with multiple groups of resistors with different resistance values, and a switch is provided between each group of resistors and the controller. During specific implementation, when the current induced voltage is greater than the preset first threshold value, the switches of one or more groups of resistors in the induced voltage elimination device are controlled to be turned on and connected in parallel at both ends of the detection line; the one or more groups The resistance of the resistor matches the current induced voltage. Thereby, the elimination of the induced voltage is realized. Another embodiment is that a plurality of circuit breakers are arranged in the induced voltage elimination device, and each circuit breaker is respectively connected to the current detection line and the lines around the detection line; when the current induced voltage is greater than the preset first threshold, the controller , switch the current detection line from the working state to the standby state through the circuit breaker, and restore the detection line from the standby state to the working state through the circuit breaker when the current induced voltage is less than the preset second threshold; the first threshold is greater than second threshold. Therefore, the induced voltage is reduced or even eliminated in a very simple manner, and the safety on the construction site is improved.

The above is a preferred embodiment of the present utility model, it should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present utility model, some improvements and modifications can also be made, these improvements and modifications It is also regarded as the protection scope of the present utility model.

Claims (8)

1. a kind of induced voltage detection device, it is characterised in that be connected including capacitive divider and with the capacitive divider Peripheral circuit, the capacitive divider include the first capacitance C0 and the second capacitance C1；The peripheral circuit includes signal cable ripple Impedance Z, build-out resistor R；

First capacitance C0 and the second capacitance C1 series connection, the first capacitance C0 and the second capacitance C1 common ports and signal cable wave impedance The pin connection of the input terminal of Z, another pin of the input terminal of signal cable wave impedance Z are another with the second capacitance C1's of electricity One end connects, and a pin of signal cable wave impedance Z output terminals is connected with one end of build-out resistor R, signal cable wave impedance Z Another pin of output terminal is connected with the other end of build-out resistor R.

2. induced voltage detection device according to claim 1, it is characterised in that further include oscillograph input resistance R2, Oscillograph input capacitance C2, the oscillograph input resistance R2 and input capacitance C2 are connected in parallel on the both ends of build-out resistor R respectively.

3. induced voltage detection device according to claim 1, it is characterised in that further include compensation resistance R1, the benefit Resistance R1 is repaid to be series between build-out resistor R and oscillograph input capacitance C2.

4. a kind of induced voltage control system, it is characterised in that including induced voltage detection device, with induced voltage detection device The oscillograph of connection, the periphery electricity that the induced voltage detection device includes capacitive divider and is connected with the capacitive divider Road, the capacitive divider include the first capacitance C0 and the second capacitance C1；The peripheral circuit include signal cable wave impedance Z, Build-out resistor R；

First capacitance C0 and the second capacitance C1 series connection, the first capacitance C0 and the second capacitance C1 common ports and signal cable wave impedance The pin connection of the input terminal of Z, another pin of the input terminal of signal cable wave impedance Z are another with the second capacitance C1's of electricity One end connects, and a pin of signal cable wave impedance Z output terminals is connected with one end of build-out resistor R, signal cable wave impedance Z Another pin of output terminal is connected with the other end of build-out resistor R.

5. induced voltage control system according to claim 4, it is characterised in that the induced voltage detection device is also wrapped Include oscillograph input resistance R2 and oscillograph input capacitance C2, the oscillograph input resistance R2 and input capacitance C2 is in parallel respectively At the both ends of build-out resistor R.

6. induced voltage control system according to claim 5, it is characterised in that the induced voltage detection device is also wrapped Compensation resistance R1 is included, the compensation resistance R1 is series between build-out resistor R and oscillograph input capacitance C2.

7. induced voltage control system according to claim 4, it is characterised in that induced voltage cancellation element is further included, One end of the induced voltage cancellation element is connected with oscillograph, the other end and the circuit to be measured of the induced voltage cancellation element Connection.

8. induced voltage control system according to claim 4, it is characterised in that the oscillograph include receiving unit, Transmitting element, microprocessor and A/D converter, waveform display unit, input terminal and the induced voltage of the receiving unit detect The output terminal connection of device, an output terminal of the receiving unit is connected with waveform display unit, the receiving unit it is another The input terminal of one output terminal and A/D converter connects, and the output terminal of the A/D converter and the input terminal of microprocessor connect, The output terminal of microprocessor is connected with transmitting element.