Device for single-phase automatic repeated connection of ultrahigh voltage lines

FIELD: electricity.

SUBSTANCE: device comprising serially connected reactor switches and shunting reactors, neutral of which includes parallel compensating reactor and breaker, capacitor batteries are additionally connected serially with shunting reactors in each phase from the side of neutral leads, shunted with switches.

EFFECT: reliability improvement.

2 dwg

 

The invention relates to techniques for the transmission of electricity alternating current, namely the transmission of ultra-high voltage (VSS).

Known apparatus for implementing a single-phase automatic reclosing (main electric networks) lines VSS (Hasibar R., Legate A.S., J. Brunke, W.G. Peterson - The Application of High-Speed Grounding Switches for Single-Pole Reclosing on 500 kV Power Systems (Application of high-speed bypass phases at the main electric networks in the transmission 500 kV). - IEEE Transactions on Power Apparatus and System, Vol.PAS-100, No.4, April 1981. - P.1512-1515.), containing shunt switches at both ends of the line, in the pause mode, the main electric networks to sexonthebeach emergency phase ends of the line and thereby reduce to acceptable levels the current arc is sustained.

The disadvantage of this device is its high cost.

It is also known a device for the implementation of the main electric networks of lines VSS, taken as a prototype (NAS, Useraccess, Snejanka. The use of compensatory reactors to facilitate main electric networks of high-voltage lines. // Electric station, 1975, No. 12. - S-72, figure 1). A device for implementing main electric networks in the line contains a shunt reactors connected to the line through the reactor switches. Single-phase short-circuit alarm off phase linear circuit breakers and neutral shunt reactors provides for the inclusion of compensation react the RA. The inclusion of the compensation reactor is by turning off the switch that bypasses the compensation reactor in normal mode. As a result, in the pause mode, the main electric networks is compensation uid tank line and correspondingly decreasing the current feed.

The disadvantage of this device is that the compensating reactor provides reduced during pause main electric networks of the electrostatic component of the current recharge and has no limiting effect on the electromagnetic component. At the same time during the dynamic transition in the pause main electric networks is an increase in the angle between the EMF adjacent systems, and accordingly, in the current arc recharge becomes the defining electromagnetic component. When the angle between the EMF adjacent systems in the range δ0÷δ0to +40° (δ0- the angle between the EMF in the source mode)that, as a rule, takes place, the electromagnetic component of the current recharge is crucial, and the total current recharge reaches 70-90 A. According to the experimental data (Useraccess. The generalization performance data efficiency of the main electric networks VL VSS and experimental data of the time of arc extinction recharge. // Electric station, 1989, No. 3. - P.65-72) when such currents feeding the duration of a pause main electric networks should be 1.8 to 3.0, and when currents in excess of 90 A successful repayment augustinowicz unlikely.

The task of the invention is the reduction of electrostatic and electromagnetic components of the current feed in order to ensure a successful main electric networks.

This object is achieved in that in the known device, containing series-connected reactor switches and shunt reactors, in a neutral position which is parallel to the compensating reactor and a switch in series with shunt reactors in each phase from neutral conclusions connected capacitor Bank, the device is activated switches.

Figure 1 shows the structural diagram of the proposed device. Figure 2 presents the dependence of the current recharge and its components from the divergence angle between the EMF adjacent systems during pause main electric networks.

The device (1) for the implementation of the main electric networks of the line 1 contains shunt reactors 2, is connected to the line circuit 3, the compensating reactor 4 with parallel switch 5 and connected in series with shunt reactors 2 batteries capacitors 6, continuely switches 7.

The device operates as follows. In the normal mode in the case of single-phase short circuit 8 emergency phase line 1 off line switches 9, after which there is a connection compensatory re ctor 4 by turning off the switch 5 and the commissioning of capacitor Bank 6 by turning off the switch 7 in phase, same with the emergency phase of the line.

To substantially reduce electromagnetic component of the current recharge and respectively of the total current to values of less than 40 A, in which is provided a successful main electric networks for 0.6 to 0.8 seconds, the resistance of the capacitor Bank should be 30-40% of the resistance of the shunt reactor. Otherwise, the arc current recharge will exceed the required value of 40 A. the capacity of the capacitor battery is relatively small and does not exceed 2-3% of the power shunt reactor.

Figure 2 illustrates the effective reduction of the electromagnetic component of the current recharge and respectively of the total current flow in the range of 40 A to line 750 kV with a length of 450 km when combined compensation of the reactor and capacitor Bank, the resistance of which is assumed to be 35% of the resistance of the shunt reactor. The value of the electrostatic component of the current recharge is also reduced.

Thus, the device containing series-connected reactor switches and shunt reactors, in a neutral position which is parallel to the compensating reactor and switch, and containing in series with shunt reactors in each phase from the neutral terminals on the capacitor Bank, the device is activated switches, allows to reduce electromagnetic who itnow and electrostatic components of the current recharge, that ensures successful main electric networks.

A device for implementing single-phase automatic reclosing of ultra-high voltage lines containing series-connected reactor switches and shunt reactors, in a neutral position which is parallel to the compensating reactor and the switch, characterized in that it introduced a battery of capacitors, the device is activated switches and installed in each phase in series with shunt reactors from neutral conclusions.



 

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