JPS6016117A - Simulating circuit of bus voltage - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Field of application of the invention] The present invention relates to substation bus voltage detection.

[Background of the invention]

Generally, PT is often installed on the bus bar to measure the bus voltage of substation equipment, but from the viewpoint of economy and safety, bus P
T may not be installed. In such a case, in order to measure the bus voltage, it is necessary to construct the bus voltage from the PT of a circuit branching from the bus. As is well known, when secondary circuits of different PTs are connected in parallel, a large current may flow through the secondary circuits, which is very dangerous.

[Purpose of the invention]

The present invention aims to solve this problem by providing a circuit configuration that can reliably simulate the bus voltage from the PT secondary circuit of the branch line without connecting the PT secondary circuit in parallel.

[Embodiments of the invention]

An embodiment according to the present invention is shown in FIGS. 1-3.

In the substation equipment having double busbars, a breaker 4 is connected to the busbar 1.2 via a busbar disconnector 3 to this busbar. The following circuit is configured to obtain the voltage of bus bars 1 and 2 from the PT5 installed in each line.

The auxiliary relay 11 is energized when the bus disconnector 3 on the bus 1 side, the breaker 4, and the PT secondary breaker 6 are all closed. The contacts of the auxiliary relay 11 are connected to the PT secondary, and are applied to the circuit that constitutes the voltage on the bus 1 side. The auxiliary relay 12 includes a bus disconnector 3 on the busbar 2 side, a circuit breaker 4 and P,
When all the T2-order circuit breakers 6 are closed, the circuit is energized. The contacts of the auxiliary relay 12 are connected to the 212nd order, and are applied to the circuit that constitutes the voltage on the bus bar 2 side.

In Figure 1, line 01 is connected to bus 1, so PT
The voltage of #5 is equivalent to the voltage of mother #1.

The FT secondary circuit is connected to the terminal 16 via the contact of the auxiliary relay 11 in a path shown by dotted lines, and the voltage of the bus 1 is obtained. Since line 02 is connected to bus 2, the P of this line is
The T voltage is equivalent to the voltage on bus 2. The PT secondary circuit is
It is connected to the terminal 17 via the contact of the auxiliary relay 14 which is energized along the route shown by the chain line and the contact of the auxiliary relay 12 returning from the line 01, and the voltage of the bus bar 2 is obtained.

In Figure 2, both lines 01 and 02 are connected to bus 1 and bus 2
indicates that it is stopped. The 212nd order of line 01 is connected to terminal 16 via auxiliary relay contact 11, and the voltage of bus 1 is obtained. At this time, the PT secondary circuit of line 02 is connected to the normally closed contact of auxiliary relay 11 via auxiliary relay 13, but since auxiliary relay 11 is energized, terminal 1
I can't touch 6. If line 01 is disconnected from bus 1 or the 212th circuit breaker is opened, auxiliary relay 11 will return and PT2 of line 01 will be disconnected.
The circuit is then disconnected, and the PT secondary circuit of line 02 is connected to terminal 16 instead, so that the voltage of bus 1 is still available.

On the other hand, since the bus 2 is stopped, no branch circuits are connected. Therefore, the terminal 17 is without voltage, which corresponds to the state of the bus bar 2.

FIG. 3 shows a case in which lines 01 and 02 are both connected to bus 1 and connected to bus 1.2 by a bus link. Second
As in the case of the figure, the 172nd voltage of line o1 is
connected to. Furthermore, the auxiliary relay 15 is energized by the bus tie breaker being turned on, and the voltage at the terminal 16 is connected to the terminal 17 via this contact, so that the voltage at the bus bar 2 is obtained.

〔Effect of the invention〕

As described above, the bus voltage can be simulated from the 172nd voltage of the branch line depending on the state of the bus disconnector and circuit breaker connected to the bus. In the simulated circuit (4), the 172nd order voltages are not connected to each other, so the voltages of different circuits will not be matched as described above.

Although the embodiment shows a two-line double-bus configuration, it is possible to cope with an increase in the number of lines and the number of buses by adding circuit breaker/disconnector conditions.

[Brief explanation of drawings]

1 to 3 show embodiments of the invention. 1.2... Busbar, 3... Busbar disconnector, 4... Breaker, 5... PT, 6... 212th order breaker, 11
~15...(5) -8;

Claims (1)

[Claims] 1. In a simulated circuit that configures the bus voltage from the PT of the bus branch line without depending on the bus voltage transformer (hereinafter abbreviated as PT), if multiple branch lines are connected to the same bus, it is optional. A bus voltage simulation circuit characterized in that it obtains a PT output of one branch line, and obtains FT outputs of each of a plurality of branch lines when connected to different buses.