CN205880060U - Accurate measurement system of direct current earthing pole ground resistance - Google Patents

Abstract

The utility model discloses an accurate measurement system of direct current earthing pole ground resistance, it includes that earthing pole, first earth connection, second earth connection, first isolation switch QS1, second septum are from switch QS2, current conversion station, voltage transformer, a plurality of remote control switch and electric current source, wherein, the near -end of first earth connection is connected with the output in electric current source, and the near -end of second earth connection is connected on the portal frame of being qualified for the next round of competitions of current conversion station, the distal end of first earth connection and the distal end of second earth connection back reconnection to the earthing pole that links to each other, on voltage transformer's once side was connected to the second earth connection, its secondary side connect a voltmeter, on the one end of every remote control switch all is connected to the second earth connection, the equal ground connection of its other end. The utility model discloses can carry out the precision measurement to earthing pole ground resistance to it assesses whether to satisfy the operation of direct current transmission system to the ground resistance of earthing pole.

Description

A kind of direct current grounding pole earth resistance accurate measuring systems

Technical field

This utility model relates to direct current grounding pole earth resistance accurate measuring technique field, is specifically related to a kind of DC earthing Pole earth resistance accurate measuring systems.

Background technology

Along with rapid development and the continuous progress of science and technology of Chinese society's economy, entire society is increasing to the demand of electric energy, Therefore electrical network scale constantly expands.But there is serious asymmetric problem in Chinese energy distribution and economic development, east and The economically developed energy in south is few, and Western Energy Resources is abundant but economy is more backward, therefore Western Energy Resources is effectively transported to east and South, contributes to the sustainable development of national economy.High-voltage direct-current technology of transmission of electricity because of its remote Large Copacity carry in excellent Gesture is obvious, and big the most existing in China hand over super extra-high voltage DC transmission system to put into operation more.

In the area that soil resistivity is high, need to reduce the earth resistance of whole DC transmission system earthing pole, reduce whole The mode of the earth resistance of individual DC transmission system earthing pole has two kinds, and one is to use earth pole or One Common Earthing Electrode, But when sharing due to multiple earthing poles, operating experience shows, due to the earth resistance of each earthing pole, One Common Earthing Electrode Each earthing pole earth current is unequal, and the earthing pole causing current distributing big is aging and ruuning situation is more severe；Another kind of Then the earth resistance of DC transmission system earthing pole accurately being measured and assessed this earthing pole, whether can to put into direct current defeated In electricity system, and the earth resistance of earthing pole can not accurately be measured by prior art.

Utility model content

The purpose of this utility model is for above-mentioned earthing pole grounding resistance measurement precision Shortcomings, it is provided that Yi Zhongwen Qualitative good, direct current grounding pole earth resistance accurate measuring systems that precision is high, earthing pole earth resistance accurately measured by it, In order to assess whether earthing pole earth resistance meets DC transmission system operation demand.

For achieving the above object, this utility model adopts the technical scheme that:

A kind of direct current grounding pole earth resistance accurate measuring systems, it includes earthing pole, the first earth lead, the second ground connection Line, the first isolation switch QS1, the second isolation switch QS2, current conversion station, voltage transformer, multiple remote control disconnecting link and current source； Wherein, on the binding post that the described near-end of the first earth lead and the outfan of current source are all connected on current conversion station, second Earth lead be proximally and distally separately installed with the first isolation switch QS1 and the second isolation switch QS2, and the second earth lead is near End is connected on the outlet portal frame of current conversion station, and the far-end of the first earth lead and the far-end of the second earth lead are then connected to after being connected Earthing pole；The primary side of described voltage transformer is connected on the second earth lead, and its secondary side also connects a voltmeter；Each remote control One end of disconnecting link is connected on the second earth lead, the equal ground connection of its other end.

Described voltmeter and one the 3rd isolation switch QS3 are in parallel with the secondary side of voltage transformer again after connecting.

Described current source includes three-phase alternating current potential source, rectification change, rectifying valve, inductance L1 and protective resistance R1, described three The most rectified change of cross streams voltage source, rectifying valve, inductance L1 and protective resistance R1 form the outfan of current source.

Described remote control disconnecting link is 5, the distance of described 5 remote control disconnecting links and the second earth lead junction point to outlet portal frame It is respectively 35%, 45%, 55%, 65%, the 75% of the second earth lead total length.

This utility model compared with prior art, has the advantage that by have developed high unidirectional current steady, high-precision Flow measurement device (i.e. current source), coordinates the voltage measuring apparatus of automatization, it is achieved that direct current grounding pole earth resistance accurate Measure, there is the advanced features such as directly perceived, quick, high accuracy, promptly and accurately grasped whether earthing pole earth resistance exists Abnormal situation.

Accompanying drawing explanation

Fig. 1 is the circuit theory diagrams of this utility model a kind of direct current grounding pole earth resistance accurate measuring systems；

Fig. 2 is the circuit theory diagrams of current source.

Detailed description of the invention

With detailed description of the invention, content of the present utility model is described in further details below in conjunction with the accompanying drawings.

Embodiment

Refer to shown in Fig. 1, a kind of direct current grounding pole earth resistance accurate measuring systems, it includes earthing pole 1, first connects Ground wire the 2, second earth lead the 3, first isolation switch QS1, the second isolation switch QS2, current conversion station 5, voltage transformer 4, Duo Geyao Control disconnecting link and current source；Wherein, (near-end of this first earth lead 2 is also connected to current conversion station to the near-end of the first earth lead 2 simultaneously On the outlet portal frame of 5) it is all connected on the binding post on current conversion station 5 with the outfan of current source, the second earth lead 3 Proximally and distally it is separately installed with the first isolation switch QS1 and the second isolation switch QS2, and the near-end of the second earth lead 3 connects On the outlet portal frame of current conversion station 5, the far-end (ground connection is extreme) of the first earth lead 2 and the far-end (earthing pole of the second earth lead 3 End) grounding electrode electric current of generation is all transferred to the earthing pole 1 that shares；Voltage transformer 4 (newly creates four directions electricity for example with Beijing The HV series voltage sensor of sub-company limited) primary side be connected on the second earth lead 3, its secondary side also connects a voltage Table, concatenates one the 3rd isolation switch QS3 in voltmeter circuit, and voltmeter reading can will measure magnitude of voltage by wireless module Send current conversion station to and measure system；One end of each remote control disconnecting link is connected on the second earth lead 3, the equal ground connection of its other end, The disconnecting link state of each remote control disconnecting link is all wirelessly transmitted to current conversion station and measures system.

Refer to shown in Fig. 2, current source is a high DC current measurement equipment steady, high-precision, and it includes three-phase alternating current Voltage source, rectification become 6, rectifying valve 7, inductance L1 and protective resistance R1, the most rectified change of three-phase alternating current potential source 6, rectifying valve 7, inductance L1 and protective resistance R1 form the outfan of current source.Wherein, rectification becomes 6 (i.e. rectifier transformers) for inputting three Cross streams voltage source conversion becomes the magnitude of voltage that rectifying valve bears, and can insulating power supply side (rectification becomes 6 primary sides) and (rectification of valve side Become 6 secondary sides) fault, Shanghai flexibility electrical equipment device fabrication company limited BK-2500VA type rectification can be used to become；Rectifying valve 7 Becoming DC ripple electric current for rectification being become the voltage transformation of 6 outputs, such as can use Toshiba's SiC Schottky barrier two pole Pipe composition rectifying valve 7, use Toshiba's SiC Schottky-barrier diode time, these diode cathodes connect two-by-two after the most also Connection, the positive terminal after parallel connection is by ground connection after inductance L2, and negative pole end is by forming current source after inductance L1 and protective resistance R1 Outfan, be connected to the change of current become binding post on.

The process accurately measured direct current grounding pole earth resistance is:

Step 1, the first isolation switch QS1, the second isolation switch QS2 and multiple remote control disconnecting link are in disconnect shape State；

Step 2, to utilize current source be I to the first earth lead 2 injected value of current₁Electric current；

Step 3, when the first isolation switch QS1, the second isolation switch QS2 are still in off-state, close i-th remote control Disconnecting link, remotely reads the reading U of voltmeter (the 3rd isolation switch QS3 is constantly in closure state) under this state_i0；Then close First isolation switch QS1, now the second isolation switch QS2 is still in off-state, reads the reading U of now voltmeter_i1；Measure After disconnect the first isolation switch QS1 and i-th remote control disconnecting link；Wherein, 1≤i≤n, n are the sum of remote control disconnecting link；

Step 4, repeat step 3, until each remote control disconnecting link be performed both by once under this remote control disconnecting link closure state two (i.e. when the second isolation switch QS2 is off, the first isolation switch QS1 is respectively at disconnection in twice measurement in secondary measurement With the measurement under closure state)；

Step 5, resistance R of calculating earthing pole earth resistance:

$R=\frac{\underset{i=1}{\overset{n}{\mathrm{\Σ}}}(U_{i1}-U_{i0})}{{\mathrm{nI}}_1}$

In this utility model preferred embodiment, integrating step 3-5, with certain two actual earth lead for measuring object, 5 remote control disconnecting links and this 5 remote control disconnecting links and the second earth lead 3 junction point is used to be respectively second to the distance of outlet portal frame 35%, 45%, 55%, 65%, the 75% of earth lead 3 total length is the physical location of remote control disconnecting link, obtains each remote control disconnecting link two Secondary measurement and final earthing pole earth resistance, as shown in table 1:

Table 1 each remote control disconnecting link secondary measurements and earthing pole grounding resistance

Step 6, being estimated earthing pole earth resistance, when R < 0.5 Europe or design require, then this earthing pole meets straight Stream transmission system service requirement.Above-mentioned earthing pole grounding resistance 0.4604 Ω is less than 0.5 Ω, the then earth resistance of this earthing pole Meet DC transmission system service requirement, can be applicable on the DC transmission system in soil resistivity height area.

These are only preferred embodiment of the present utility model, be not limited to this utility model, for this area Technical staff for, this utility model can have various modifications and variations.It is all within spirit of the present utility model and principle, Any modification, equivalent substitution and improvement etc. made, within should be included in protection domain of the present utility model.

Claims (4)

1. a direct current grounding pole earth resistance accurate measuring systems, it is characterised in that it includes earthing pole (1), the first ground connection Line (2), the second earth lead (3), the first isolation switch QS1, the second isolation switch QS2, current conversion station (5), voltage transformer (4), Multiple remote control disconnecting links and current source；Wherein, the described near-end of the first earth lead (2) is all connected to change with the outfan of current source Stream station (5) on a binding post on, the second earth lead (3) be proximally and distally separately installed with the first isolation switch QS1 and Second isolation switch QS2, and the near-end of the second earth lead (3) is connected on the outlet portal frame of current conversion station (5), the first earth lead (2) far-end and the far-end of the second earth lead (3) are then connected to earthing pole (1) after being connected；Described voltage transformer (4) is once Side is connected on the second earth lead (3), and its secondary side also connects a voltmeter；One end of each remote control disconnecting link is connected to second and connects On ground wire (3), the equal ground connection of its other end.

Direct current grounding pole earth resistance accurate measuring systems the most according to claim 1, it is characterised in that described voltmeter After connecting with one the 3rd isolation switch QS3 in parallel with the secondary side of voltage transformer (4) again.

Direct current grounding pole earth resistance accurate measuring systems the most according to claim 1, it is characterised in that described current source (6), rectifying valve (7), inductance L1 and protective resistance R1, described three-phase alternating current potential source is become including three-phase alternating current potential source, rectification The most rectified change (6), rectifying valve (7), inductance L1 and protective resistance R1 form the outfan of current source.

Direct current grounding pole earth resistance accurate measuring systems the most according to claim 1, it is characterised in that described remote control cutter Lock is 5, and the distance of described 5 remote control disconnecting links and the second earth lead (3) junction point to outlet portal frame is respectively the second ground connection 35%, 45%, 55%, 65%, the 75% of line (3) total length.