CN2650145Y

CN2650145Y - Power line earthing point positioning instrument

Info

Publication number: CN2650145Y
Application number: CN 03271299
Authority: CN
Inventors: 桑在中
Original assignee: ZHENXIN GENERAL POWER AND ELECTRONIC EQUIPMENT PLANT JINAN
Current assignee: ZHENXIN GENERAL POWER AND ELECTRONIC EQUIPMENT PLANT JINAN
Priority date: 2003-08-08
Filing date: 2003-08-08
Publication date: 2004-10-20
Anticipated expiration: 2013-08-08

Abstract

The utility model is an electric circuit earthing point finder, which consists of a host and a signal current detector, and is characterized in that: the host is internally arranged with a built-in DC high voltage generator, the built-in DC high voltage generator consists of a commutation filter loop, a high frequency oscillator, an amplifying circuit, a high frequency step-up transformer, a high voltage commutation filter circuit and a constant current circuit; the utility model is applicable for positioning an one-way earthing point of a high electric overhead line, during using, the tested earthing line can be applied with the DC high voltage, the earthing point is rebroken down and the breakdown state with constant current is maintained, then an AC signal is refilled to trace, namely ''DC open, AC trace'' new method to realize the positioning of fault point, the troubleshooting efficiency can be improved 500-600 times, the powered off duration is reduced, and the remarkable social and economic benefits for the power supply parties and the users are realized.

Description

Power circuit earth point orientator

Technical field

The utility model belongs to the power equipment detection range, is applicable to that the single-phase earthing point to the high-tension electricity overhead transmission line positions.

Background technology

In the power delivery of China's distribution system, the 6--35KV overhead transmission line is positioned at the tip of high pressure transfer path, and it is wide to distribute, and is exposed to again in the middle of the Nature, expose to the weather, and the thunder and lightning invasion and attack, the probability of single-phase earthing is quite high.

When power circuit generation single-phase earthing, as only depend on the maintenance personal artificial visually examine to search, the person will cross over mountain after mountain to search the earth point, steps on the bar scrutiny by root, expends a large amount of manpower and materials; Also can therefore incur loss through delay electric power feeding time, cause damage for power supply department and power consumer.

The detecting instrument of the present location power failure of using always, be to adopt Low Voltage Impulse Method, institute is surveyed the direct and surveying instrument generation electric coupling of cable high tension loop, the transient voltage or the current signal waveform that produce by instrument record with when showing that cable fault punctures, and come the suspected fault distance according to this waveform.There are the following problems aspect result of use, and the one, wireline inspection is carried out under charged situation, and other infringements take place easily, as track walker's job safety, perhaps meets thunderstorm weather, very easily causes out of phase 2 ground connection to produce step voltage etc.; The 2nd, degree of accuracy is not high, earth point often occurs and can not find next situation.

Summary of the invention

The purpose of this utility model provides a power circuit earth point orientator, uses it can find earth point quickly and accurately under power-off condition.

The utility model is to adopt surveys ground path is added high direct voltage, punctures earth point again, and the AC signal of reinjecting is also sought track, i.e. the new method of " direct current is opened a way, interchange seek track " realizes localization of fault.Promptly be built-in with high voltage direct current generator at instrument host.

This detecting instrument comprises main frame and marking current detector two parts.Main frame is made of high voltage direct current generator, AC signal generator, power amplifier and control loop; The marking current detector is formed by connecting by resonant tank, frequency-selecting amplifier, rectification filtering circuit and display.

The ac input end of said high voltage direct current generator is parallel with rectification filtering circuit, high frequency oscillation, amplifying circuit, high-frequency step-up transformer, high pressure, rectifier filter circuit; "+" output terminal is in series with the weighing apparatus current circuit.

Also be provided with in the main frame injecting power amplifying part and the step-up transformer that signal amplifies and boosts.

Below in conjunction with accompanying drawing the utility model is described further.

Description of drawings

Fig. 1 constitutes schematic diagram for main frame, Fig. 2 is the circuit diagram of high pressure generator 7, and Fig. 3 is for injecting the circuit diagram of signal generator 14, and Fig. 4 is the circuit diagram of power amplifying part 17, Fig. 5 is the circuit diagram of marking current detector, and Fig. 6 is the fundamental diagram of power circuit single-phase earthing point location instrument.Fig. 7 is a plurality of branch testings figure as a result.

The main frame principle of compositionality as shown in Figure 1. 2,3 is the AC 220 V power input terminal, 4 Be " sending high pressure " button, 5 is contactor, and 6 are " stopping " button, and 7 are the high direct voltage generation Device after breakdown between lead-out terminal, can become the constant-current source of 40mA, and 8 is current-limiting resistance; 9 Be the high-tension current table; 10 is high-tension voltmeter, and 23,24 is the High voltage output terminal. Work as input When 2,3 of sons add AC 220 V voltage, by sending high pressure button 4, on the contactor coil 5 Just have 220 volts of voltages, this moment, two normal opened contact 5-1,5-2 of contactor will be closed, Wherein 5-1 is used for to sending the self-sustaining of high pressure button 4, and contact 5-2 is added in 220 volts of voltages On the high voltage direct current generator 7, it is defeated that its high-voltage output end just has 12000 volts DC voltage Go out, this high pressure is added on the lead-out terminal 23,24. The number of high-tension voltmeter 10 indication high pressure Value; The size of high-tension current table 9 indication High voltage output electric current. When pressing sender button 11, send out Have 220 volts of voltages on the coil of news contactor 12, its normal opened contact 12-1,12-2 closure, 12-1 is used for self-sustaining, and 12-2 is used for adding 220 volts of voltages to Switching Power Supply 13, this moment switch Give signal generation with 15 volts of power supplys divides 14 to power supply 13 on the one hand, on the other hand with 65 volts of electricity Force feed is given power amplifier part 17. After signal generation divides 14 to obtain power supply, just have frequently Rate is f. Signal take place, voltmeter 15 is used to refer to the size of AC signal, this frequency is F. AC signal input to power amplifying part 17 through input transformer, through the letter of power amplification Number be f via inductance 18 and electric capacity 19 component frequencies. Resonant tank, give output transformer 20, the AC signal that boosts through output transformer send through capacitance 22 and output current table 21 To output 23,24.

The circuit of high pressure generator 7 as shown in Figure 2,25,26 is the AC 220 V input terminal, 27,28 be respectively rectification filtering circuit, 29 is high frequency oscillation, amplifying circuit, and 30 is the high frequency liter Pressure transformer, 31,32 is high pressure, rectifier filter circuit, 33 are the weighing apparatus current circuit, 34, 35 are HVDC output terminal.

The circuit of Injection Signal generator 14 as shown in Figure 3,36 is the high frequency oscillation circuit, 37 Be frequency dividing circuit, it becomes frequency with high-frequency signal is f. Injection Signal, 15 for injecting letter Number voltmeter, 38 is pre-amplification circuit, 39 is capacitance, 40,41 for Injection Signal defeated Go out terminal.

The circuit diagram of power amplifying part 17 as shown in Figure 4,42,43 is that direct current 65V power supply is defeated Enter terminal, 44,45,46,43 is the Injection Signal input, and 47,48 is blocking diode, 49,50 are the protection diode, and 51,52 are the power amplification triode, and 53 is capacitance, 54, 43 is the lead-out terminal of power amplifying part.

The circuit diagram of signal code detector as shown in Figure 5. 56 for accepting antenna, and it is by Φ 10 * 200 ferrite bars and two coils form. Primary coil and resonant capacitance 55 consist of f. Resonant tank, secondary side coil are input to selective frequency amplifier circuit 57, and this amplifying circuit only amplifies f. Frequency signal and do not amplify power frequency and each harmonic thereof, through 57 amplifying signals through diode 58 Again through electric capacity 59 filtering, deliver to the display part by the normally closed contact of navigation button 61 after the rectification 62, the effect of display part is the size of display electric current. When pressing navigation button 61, Signal through rectification, filtering is delivered to the display part again through direct current amplification 60 again, and direct current amplifies to be thrown Enter is in order to improve the signal code detector sensitivity.

Embodiment

The principle of work of power circuit single-phase earthing point location instrument as shown in Figure 6.Among the figure: 63,64,65 be respectively the A of transformer station, B, C phase bus; 66,67,68 be respectively A, B, C phase power circuit; 69,70,71 is A, B, the C phase bus disconnecting link of this circuit; 72,73,74 is A, B, the C phase switch of this circuit, and 75,76,77 is A, B, the C phase circuit disconnecting link of this circuit.When single-phase earthings take place in electric power route road C phase 68, the position that just can search earth point 78 with this instrument.

The first step that detects is that ground path is had a power failure, and promptly the open-circuit line switch 72,73,74, disconnects bus disconnecting link 69,70,71, and the open-circuit line disconnecting link 75,76,77 again.Lead-out terminal 24 good earths with earth point orientator 1, lead-out terminal 23 is connected on the ground path ground connection phase 68, connect 220 volts of AC power, by sending the high pressure button, high pressure generator just has 12000 volts of high pressure and is added on the earth point 78, earth point is punctured, inject 40mA direct current continuous current then, shown in dotted line 79; Press sender button 11 again, just having frequency is f.AC signal current be injected into earth point, shown in dotted line among Fig. 6 80.Can produce the principle in magnetic field according to electric current, it is f that frequency must be arranged.Alternating flux accompaniment signal electric current 80, with the marking current detector to frequency f.Alternating flux seek track, just can find earth point easily.As test line branch line is arranged, then leave 6 meters of take-off points, make the bar magnet of marking current detector vertical with survey branch, respectively two branches are measured, the marking current table is made inclined to one side person and is ground connection branch; To be zero person be non-ground connection branch to marking current.

Fig. 7 has provided a plurality of branch testing results.Among the figure, 81 is transformer station, and 82 is ground path grounded phase wire road, and 83 is first branch, and 84 is second branch, and 85 is earth point, and dotted line 86 is f for frequency.Marking current." O " expression signal sensor display part 62 is designated as 0 among the figure; " expire " expression signal communication detector display part 62 indication full scales.

When power circuit generation earth fault, two, 30 people often several days also difficulty find the earth point accurate location, adopt this instrument, two people half an hour just can be with the earth fault point location, thereby can improve line fault point search efficiency 500--600 doubly, shortened power off time greatly, effectively improved power supply reliability, all can produce tangible economic and social benefit power supply department and power consumer.

Claims

1, a kind of power circuit earth point orientator is made up of main frame and marking current detector, it is characterized in that being built-in with high voltage direct current generator at main frame.

2, according to the described power circuit earth point of claim 1 orientator, it is characterized in that this high voltage direct current generator is by rectification filtering circuit, high frequency oscillation, amplifying circuit, high-frequency step-up transformer, high-voltage rectifying filtering circuit and weighing apparatus current circuit are formed.

3,, it is characterized in that being provided with in the main frame to injecting power amplifying part and the step-up transformer that signal amplifies and boosts according to the described power circuit earth point of claim 1 orientator.

4,, it is characterized in that the marking current detector is formed by connecting by resonant tank, frequency-selecting amplifier, rectification filtering circuit and display according to the described power circuit earth point of claim 1 orientator.