JPS6350939B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a timed fault investigation device used for automatic fault section detection in a multi-loop power distribution system.

Technical background of the invention The function of the time-limited accident investigation device is that there is voltage on the power supply side.
Turn on the switch after a certain period of time under load-side power outage conditions.
If the power goes out within a certain period of time after that, the switch is locked, and even if the conditions of voltage on the power supply side and power outage on the load side are met again, the switch will not be turned on.

In Fig. 1, CB is a substation's distribution line drawer and disconnector, which is normally in the ``on'' state and the distribution line A is pulled out.

The distribution line A is divided into sections by section switches S ₁ , S ₂ , S ₃ combined with time-limited accident investigation devices, and is normally in the "on" state. The section is connected to the distribution line B via the loop point switch _L1 , and the section is connected to the distribution line C via the loop point switch _L2 , and these loop point switches _L1 ,
_L2 is normally in the "off" state.

Now, if an accident occurs in this section,
Although I will not go into details, power is finally transmitted through the section by the operation of the distribution line drawer and disconnector CB: disconnect → reclose → reclose → reclose. Further, the time-limited accident investigation device combined with the division switch _S1 is locked by its function, and the division switch _S1 remains in the "off" state. In addition, segment switches S ₂ and S ₃
is also in the "off" state.

Next, for the healthy section, distribution lines B and C
More flexible power transmission. i.e. loop point switch
Manually turn on _L2 , and as a result, interchange power is transmitted from distribution line C to the section. Then the loop point switch
Manually turn on _L1 , and as a result, interchange power is transmitted from distribution line B to the section.

As a result of the above operations, power is cut off in the section of the power distribution line A that is the accident section, power is transmitted from the power supply side to the section, and power is transferred from the power distribution lines B and C to the section.

Problems with the Background Art Next, suppose that an accident occurs again in the section in this state. Since power is transmitted to the section from distribution line C, an accident is detected on distribution line C and the section experiences a power outage. However, in this case, when a power outage occurs in a section, the time-limited accident investigation device combined with the section switch S ₃ detects a power outage in the load side section (section) and a voltage presence in the power supply side section (section). After a certain period of time, the section switch _S3 is turned on.

Since the section is already receiving interchangeable power transmission from distribution line B, distribution line B will detect an accident in the section, and distribution line B will also experience a power outage.

Depending on the severity of the accident, it may even spread to normally healthy distribution lines, which could impair supply reliability.

In addition, when performing power outage work in a section with no accidents occurring in the section, that is, in a state where power is being transmitted interchangeably from distribution lines B and C, loop point switch _L2 must be turned off. If the operation is performed, the power will be cut off in the section, but in this case as well, when the section is out of power, the time-limited accident investigation device combined with the section switch S ₃ will detect a power outage in the load side section (section) and a voltage failure in the power side section (section). After a certain period of time, the section switch S ₃ is turned on due to its function.
controlled, and the section ends up being charged again.

This is not only unfavorable in terms of work safety, but may also lead to personal injury.

Purpose of the Invention The present invention has been made in order to solve the above-mentioned drawbacks all at once.The power supply side section of the sectional switch is charged, and the load side section is charged by receiving power from another distribution line. The purpose of this invention is to provide a time-limited accident investigation device that is safe and does not reduce supply reliability by preventing the sectional switch from being turned on even if the load side section has a power outage. shall be.

Summary of the invention The presence or absence of voltage on both sides of a switch installed on a high-voltage distribution line is input, and the state does not change even if the high-voltage distribution line is out of power. The reset input condition is when the voltage is applied and continues for a certain period of time, or when the switch is OFF and voltage is applied to both sides of the switch. "Enter"
A memory circuit is provided that is configured to output when the reset state continues for a certain period of time or when a manual signal is input, and when the reset state changes to the set state, and at least this memory circuit has an output and is open/closed. When the switch is "off" and voltage is applied to both sides of the switch, the output holding circuit turns the switch "on".
This is a time-limited accident investigation device that outputs a control output.

Embodiment of the Invention An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a configuration diagram showing an embodiment of the present invention. In Figure 2, 1 is the power supply side high voltage distribution line,
2 is a load-side high-voltage distribution line, 3 is a switch, and a time-limited accident investigation device 6 is supplied with power from power supplies 4 and 5 connected to the high-voltage distribution lines 1 and 2. AND circuit a that determines no voltage;
Timer circuit b that outputs an output when the output of AND circuit a continues for a certain period of time, voltage on the power supply side, voltage on the load side, AND circuit c that outputs when there is no output from output holding circuit k (described later), output of timer circuit b OR circuit d outputs an output when there is an output from AND circuit c, AND outputs an output when there is a voltage on the power supply side and there is an output from output holding circuit k, which will be described later.
When the output of circuit e and AND circuit e continues for a certain period of time, the timer circuit f produces an output, and the output of OR circuit h and OR circuit d produces an output when there is an output from timer circuit f or when switch g is closed. It is set to “1” and reset to “0” by the output of OR circuit h, and does not change even if the power is cut off.
A memory circuit i that outputs an output only when it is inverted from "0" to "1", an AND circuit j that outputs only when there is an output from memory circuit i and no output from AND circuit c, and an output from AND circuit j. It is composed of an output holding circuit k that holds the output until the power is cut off, and its output is connected to the operating circuit 31 of the switch 3.

In the above configuration, the memory circuit i is set to "0" as an initial state. Here, power supply side high voltage distribution line 1
When electricity is supplied to the time-limited accident investigation device 6, electricity is supplied only from the power supply device 4,
Circuit a has an output. If this state continues for a certain period of time (turn-on time limit), an output is output from timer circuit b, which inverts memory circuit i from "0" to "1" via OR circuit d, so memory circuit i outputs an output. .
On the other hand, AND circuit c does not output because it is in a power outage state on the load side. Therefore, the AND circuit j outputs an output on the condition that there is an output from the memory circuit i and no output from the AND circuit c, and the output is maintained by the output holding circuit k until the power is cut off and the output is applied to the switch 3. is applied to the operating circuit 31, the switch is controlled to be "on",
Remains "on" until the power is turned off.

When the switch 3 is in "on" control, that is, when an output is output to the output holding circuit k, the AND circuit e outputs an output on condition that the power supply side voltage is present and there is an output from the output holding circuit k. This state remains for a certain period of time (detection time limit)
If it continues, an output is output from the timer circuit f, and the memory circuit i returns to the "0" state via the OR circuit h and becomes the initial state.

In addition, in the above, if the output of the AND circuit e disappears within a certain period of time (detection time limit), that is, if an accident occurs in the load-side high-voltage distribution line 2, the high-voltage distribution line 1 will be removed at a substation (not shown). Since the supply of electricity is stopped, when the condition of AND circuit e is not satisfied and there is no output, timer circuit f stops before outputting, and timer circuit f stops before outputting, and time-limited accident investigation device 6 changes to memory circuit i.
While it is set to "1", the output to the switch 3 is stopped.

Next, when the substation sends electricity to the high-voltage distribution line 1 again, the time-limited accident investigation device 6 will continue to have the voltage on the power supply side for a certain period of time, so an output will be output from the timer circuit b in the same way as described above. Memory circuit i is set to "1", but since memory circuit i was in the "1" state, no output is output from memory circuit i, so AND circuit j
There is no output, therefore no output is output from the output holding circuit k, and the switch 3 is not controlled to be turned on.
This means that the load-side high-voltage distribution line 2 where the accident occurred has been disconnected. In other words, the time-limited accident investigation device 6
is now locked.

After this, in order to recover from the accident and release the lock on the time-limited accident investigation device 6 to return it to its initial state, it is sufficient to operate the switch g and reset the memory circuit i to "0".

In addition, in Fig. 2, the system is switched due to a system failure, power outage construction, etc., and the switch 3 is the contact point, that is, the switch 3
is in the "off" state, that is, the output holding circuit k has no output, and the load-side high-voltage distribution line 2 is charged by interchange power transmission from another distribution line (not shown), while the power-side high-voltage distribution line 1 is In the state where it is charged and the memory circuit i is reset to "0", the time-limited accident investigation device 6 is supplied with electricity from both the power supply device 4 and the power supply device 5, so the AND circuit c is connected to the voltage on the power supply side. , the load side voltage is present, and the output holding circuit has no output. As a result, the memory circuit i is inverted from "0" to "1" through the OR circuit d, so that the memory circuit i outputs an output.
However, since AND circuit j has the output of AND circuit c, the condition is not met and no output is made.

Therefore, the output holding circuit k also does not output, and the switch 3
is not controlled as “on”. In this state, if the load-side high-voltage distribution line 2, which is receiving interchange power from other distribution lines, is out of power due to an accident or power outage construction,
The time-limited accident investigation device 6 is now supplied with electricity only from the power supply device 4, and the AND circuit a has an output. When this state continues for a certain period of time (turn-on time limit), an output is output from timer circuit b, passes through OR circuit d, and sets memory circuit i to "1", but memory circuit i is already in the state of "1" as described above. Therefore, since no output is output from the memory circuit i, no output is output from the AND circuit j, and therefore no output is output from the output holding circuit k, and the switch 3 is not controlled to be turned on but is turned off.
Since the state is maintained, the load side high voltage distribution line 2 is not charged. In other words, the time-limited accident investigation device 6 is locked.

Although the above-mentioned embodiment of the time-limited accident investigation device according to the present invention has been explained using a logic diagram for simplicity of explanation, the circuit configuration can be realized using various elements such as relays, transistors, ICs, and microprocessors. In addition, the present invention can be modified and implemented in various ways without changing the spirit thereof.

Effects of the Invention As described above, according to the present invention, when the power supply side section of a sectional switch is charged and the load side section is receiving interchange power from another distribution line, the load side section is prevented from power outage. Even if the sectional switch is not turned on, it is possible to provide a time-limited accident investigation device that is safe and does not reduce supply reliability.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining a conventional device, and FIG. 2 is a configuration diagram showing an embodiment of the present invention. CB...Distribution line disconnector, Sn, Ln...
Distribution system switch, 1... Power supply side high voltage distribution line, 2...
...Load-side high-voltage distribution line, 3... Switch, 4, 5...
Power supply device, 6...Timed accident investigation device, a, c,
e, j...AND circuit, b, f...timer circuit,
d, h...OR circuit, g...Switch, i...Memory circuit, k...Output holding circuit.

Claims (1)

[Claims] 1. In a time-limited accident investigation device that uses a memory circuit in which the voltage status of high-voltage distribution lines on both sides of a switch is input and whose status does not change even in a power outage, the set input conditions of the memory circuit are set to the voltage status of the high-voltage distribution lines on both sides of the switch. When voltage is applied only on the power supply side and continues for a certain period of time, or when the switch is "off" and voltage is applied on both sides of the switch, the reset input condition for the memory circuit is set when voltage is applied on the power supply side of the switch and when the switch is opened/closed. The switch is "ON" for a certain period of time or manually, and the memory circuit is configured to output when the state changes from the reset state to the set state, and at least this memory circuit has an output and the switch is "OFF". A time-limited accident investigation device, characterized in that when voltage is applied to both sides of the switch, an output holding circuit outputs an "in" control output to the switch.