JPH08251809A - Tester of switch slave station - Google Patents

Abstract

PURPOSE: To protect a tester from the overvoltage, of an input power supply, caused by the error of the connection of a cable to a switch slave station when the switch slave station, for switch control, which is installed additionally to the switch of a power system such as a section switch or the like is to be tested. CONSTITUTION: A tester is provided with a three-terminal-constitution receiving terminal part 8 which is connected, by a cable, to the terminal part 5 of a control power supply in a switch slave station 4, with a voltage monitoring relay 11 which detects whether a voltage across two reamaining terminals excluding a neutral-line terminal at the terminal part 8 is a proper voltage or not on the basis of the normal connection of the cable and with a contact part 12 which closes a power-supply passage across the receiving terminal part 8 and a test circuit 9 on the side of a load only when the relay 11 has detected the proper voltage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch slave station tester used for testing a switch slave station of an electric power system, and more particularly to protection from an overvoltage caused by a wrong connection of its input power source.

[0002]

2. Description of the Related Art Conventionally, a switch of a power transmission and distribution system, which is one of switches of a power system, is provided with a switch slave station for controlling the switch. This switch slave station operates by a single-phase 3-wire control power source taken out from the system via a pole transformer, etc., and monitors the occurrence of accidents on the upstream and downstream sides of its own segment switch. , Exchanges information with a parent station such as a substation or sales office of an electric power company, and controls the division switch of its own station based on the exchange of this information.

By the way, a switch slave station tester is used to test the function of the switch slave station during installation and maintenance. Next, this conventional switch slave station tester will be described with reference to FIG. 1 showing one embodiment of the present invention.

As shown in FIG. 1, a section switch 2 of system 1
For example, the pole-side transformer 3 on the upstream side takes out the control power source for the single-phase 3-wire, and this control power source is fed to the switch slave station 4, and its terminal portion 5 has terminals A ₁ , N for the single-phase 3-wire. _The control power is externally output from ₁ and C ₁ .

The terminal N ₁ is a grounded neutral terminal, and the voltages V _1a and V _1c between the terminal N ₁ and the remaining two terminals A ₁ and C ₁ are 105 V (normal). Voltage), and at this time, the voltage V _1ac between the terminals A ₁ and C ₁
Becomes 210V.

At the time of the test, the switch slave station tester 6 is carried to the installation place of the switch slave station (hereinafter referred to as the test slave station) 4 to be tested.

Further, each terminal A ₁ , N ₁ , C of the terminal portion 5
₁ for each wire 7a, 7n, 7c of the single-phase 3-wire power cable 7
Is connected to one end on the power source side, and the other end on the load side of each of the wires 7a, 7n and 7c is connected to each terminal A ₂ , N ₂ and C ₂ of the power receiving terminal portion 8 of the switch slave station tester 6.

By this cable connection, the control power supply for the terminal portion 5 is supplied to the switch slave station tester 6 via the power supply cable 7. Then, the control power of the power receiving terminal portion 8 is supplied to the test circuit 9 as the load side circuit portion, and the switch slave station tester 6 operates.

The white arrow in the figure indicates the feeding direction. Further, the power cable 7 is usually formed by a crocodile clip or the like at the end of each wire so that the connection and disconnection thereof can be easily performed.

[0010]

In the case of the above-mentioned conventional switch-substation tester, the load side test circuit 9 is directly connected to the power receiving terminal portion 8 and the input power source of the power receiving terminal portion 8 is unconditionally used as it is. 9 is powered. Then, the input power source of the power receiving terminal portion 8 is obtained by a worker connecting the alligator clip of each line of the power cable 7 to each terminal of the terminal portions 5 and 8 for each test.

At this time, the power cable 7 is erroneously connected due to a work mistake or the like, and the connection states of the terminals 5 and 8 are as follows: the terminal A ₁ is the terminal A ₂ , the terminal N ₁ is the terminal N ₂ , and the terminal C ₁ is the terminal. C ₂ is not connected state of normal respectively connected, for example, as shown in Figure 2 of one embodiment the present invention, the terminal a ₂ to terminal a _1, terminal C ₂ to terminal N _1, terminal to terminal C ₁ When N ₂ is connected to each other in an erroneous connection state, the power receiving terminal portion 8
In the input power source, the voltage V _2a between the terminals A ₂ and N ₂ is the voltage V _1a.
Is not the original voltage (105 V) based on the voltage V1ac, but is double the overvoltage (210 V) based on the voltage V _1ac , and the terminals A ₂ and C ₂
The voltage V _2ac between _them is halved to ₁₀₅ V _which is the voltage V _1a , which is abnormal.

Due to the abnormality of the input power source, the overvoltage between the terminals A ₂ and N ₂ is conventionally applied to the test circuit 9 as it is, so that the test circuit 9 is damaged and the tester 6 fails. There is a problem to do.

The present invention, when testing a switch slave station attached to a switch of a power system such as a section switch, switches from an overvoltage of an input power source due to an error in cable connection with the switch slave station. The purpose is to protect the device testing equipment.

[0014]

In order to achieve the above-mentioned object, in the switchgear slave station tester of the present invention, a power receiving device having a three-terminal structure is connected to a terminal portion of a control power source of the switchgear slave station by a cable. The voltage detecting means for detecting whether the voltage between the terminal portion and the remaining two terminals except the neutral terminal of the power receiving terminal portion is a proper voltage based on the normal cable connection, and the voltage detecting means detects the proper voltage. And a power supply control unit that closes the power supply path between the power receiving terminal section and the load side circuit section only.

[0015]

In the switch slave station tester of the present invention configured as described above, the normal voltage between the neutral wire terminal and the remaining two terminals of the terminal portion of the control power source of the switch slave station is set. Eg 1
If it is set to 05V, when a wire different from the neutral wire is connected to the neutral wire terminal of the power receiving terminal due to a wrong connection of the cable between the control power source terminal of the switchgear slave station and the power receiving terminal, the power receiving terminal The voltage between the neutral wire terminal and one of the remaining two terminals is an overvoltage (2V) that is twice the original voltage (105V).
10V), and the input power supply is abnormal.

At this time, the voltage between the remaining two terminals of the power receiving terminal is half the proper voltage (210 V) (105
V), and the voltage detecting means detects that the voltage between these two terminals is not an appropriate voltage.

When the voltage detecting means detects that the voltage is not the proper voltage, the power feeding control means does not close the power receiving terminal portion and the load side circuit portion but keeps them open, so that the load side circuit portion receives an input. The overvoltage of the power supply is not applied, and the switchgear slave station tester is protected.

On the other hand, when the cable connection between the terminal portion of the control power source of the switch slave station and the power receiving terminal portion is correct, the voltage between the remaining two terminals of the power receiving terminal portion becomes an appropriate voltage, and the voltage detecting means operates. The proper voltage is detected, the power supply control means closes the power supply path between the power receiving terminal portion and the load side circuit portion based on this detection, and the load side circuit portion is safely supplied with power.

[0019]

EXAMPLE One example will be described with reference to FIGS. In FIG. 1, the switch slave station tester 6 is different from the conventional one in that a voltage monitoring unit 10 is provided between the power receiving terminal unit 8 and the test circuit 9.

The voltage monitoring unit 10 is composed of a voltage monitoring relay 11 provided between the terminals A ₂ and C ₂ of the power receiving terminal unit 8 and a normally open contact section 12 of the relay 11. Form a voltage detecting means, and the contact portion 12 form a power supply controlling means.

The voltage V _1a between the terminals A ₁ and N ₁ of the terminal section 5 of the switch slave station (test slave station) 4 and the terminals C ₁ and N ₁
The specified value (specified voltage) of the voltage V _1c between them becomes 105 V,
The specified value of the voltage V _1ac between the terminals A ₁ and C ₁ is 21 times that value.
When the voltage becomes 0 V, the voltage monitoring relay 11 has an operating voltage of 21
It is set to 0V.

The contact portion 12 is composed of three interlocking normally open contacts P ₁ , P ₂ and P ₃ , and the respective contacts P ₁ , P ₂ and P ₃ are the respective terminals A ₂ and N _{2 of the power} receiving terminal portion 8. , C ₂ and the test circuit 9 on the load side thereof, respectively.

When the power cable 7 is properly connected during the test, and the terminal A _{1 is connected} to the terminal A ₂ , the terminal N ₁ is connected to the terminal N ₂ , and the terminal C ₁ is connected to the terminal C ₂ as shown in FIG. , The voltage V _2a between the terminals A ₂ and N ₂ of the power receiving terminal portion 8,
The voltage V _2c between the terminals C ₂ and N ₂ coincides with the voltages V _1a and V _1c to become the specified voltage of 105V, respectively.

At this time, the voltage V _2ac between the terminals A ₂ and C ₂
Becomes a proper voltage (specified voltage) of 210 V in agreement with the voltage V _1ac , and the voltage monitoring relay 11 is energized and excited by the application of this proper voltage, and a proper voltage based on a normal cable connection between the terminals A ₂ and C _2. Is detected.

Further, by energizing and exciting the voltage monitoring relay 11, the contacts P ₁ , P ₂ and P _{3 of the} contact portion 12 are closed, and the power feeding path between the power receiving terminal portion 8 and the test circuit 9 is closed. The test circuit 9 is the input power source (control power source) of the power receiving terminal section 8.
Works with.

On the other hand, the connection of the power cable 7 is not correct at the time of the test. For example, as shown in FIG. 2, the terminal A _{1 is connected} to the terminal A ₂ , the terminal N ₁ is connected to the terminal C ₂ , and the terminal C ₁ is connected to the terminal N _2. Then, the voltage V _2c between the terminals C ₂ and N ₂ of the power receiving terminal portion 8 coincides with the voltage V _1c and becomes the specified voltage of 105 V, but the voltage V _2a between the terminals a ₂ and N ₂ is the voltage V _1ac. And an overvoltage of 210 V, which is twice the specified voltage.

At this time, the voltage V _2ac between the terminals A ₂ and C ₂
Is equal to the voltage V _1a and is only half of the specified voltage, which is 105 V. The voltage monitoring relay 11 does not operate because of insufficient voltage, and the voltage between the terminals A ₂ and C ₂ is not an appropriate voltage due to an incorrect cable connection. To detect.

Since the voltage monitoring relay 11 does not operate due to insufficient voltage, the contacts P ₁ , P ₂ ,
P ₃ is held open, the power supply path between the power receiving terminal portion 8 and the test circuit 9 is held open, the overvoltage of the input power source is not applied to the test circuit 9, and the test circuit 9 is protected from the overvoltage. The failure of the tester 6 due to the abnormality of the input power source is prevented in advance.

[0029] Unlike the case of FIG. 2, the terminal N ₂ to the terminal A ₁ by erroneous connection of the power cable 7, the terminal A ₂ to the terminal N _1, terminal C ₂ respectively connected to the terminals C _1, terminals C _2, The voltage V _2c between N ₂ is an overvoltage (21
0 V), the voltage V _2ac between the terminals A ₂ and C ₂
Is equal to the voltage V _1c and is 105 V which is half of the specified voltage, the voltage monitoring relay 11 does not operate due to insufficient voltage, and the power feeding path between the power receiving terminal portion 8 and the test circuit 9 is held open.

In the case of this embodiment, since the voltage detecting means and the power feeding controlling means are formed by the voltage monitoring relay 11 and the contact portion 12 thereof, the relay can be used, the cost is low, and the battery is used for driving the relay. There is also an advantage that it can be formed extremely simply and inexpensively without requiring a power source such as.

By the way, it is needless to say that the present invention can be applied to the case where the voltage of the control power supply is different from that of the embodiment.

Further, the voltage detection means and the power supply control means may be other than the relay. For example, the tester 6 is provided with a battery power supply, and the voltage detection means and the power supply are supplied by a voltage detector operated by this power supply, an analog switch or the like. The control means may be formed.

Of course, it can be applied to a tester of a switch slave station attached to various switches of the power system.

[0034]

Since the present invention is configured as described above, it has the following effects.

When the cable is erroneously connected to the switchgear slave station, the voltage between the remaining two terminals except the neutral wire terminal of the power receiving terminal portion drops to half the proper voltage that is originally applied,
The voltage detection means detects that the voltage between the two terminals is not an appropriate voltage, and based on this detection, the power feeding control means holds the power receiving terminal portion and the load side circuit portion in an open state without closing the circuit. When the input power source is abnormal, it is possible to prevent overvoltage from being supplied to the load side circuit section and protect the switchgear slave station tester, thus significantly improving safety and reliability.

[Brief description of drawings]

FIG. 1 is a connection diagram of an embodiment of the present invention.

FIG. 2 is a partial wiring diagram when the cable connection in FIG. 1 is incorrect.

[Explanation of symbols]

 1 system 2 division switch 4 switch slave station 5 control power supply terminal 7 power cable 8 power receiving terminal 9 test circuit as load side circuit 11 voltage monitoring relay 12 as voltage detection means 12 contact part as power supply control means

Claims (1)

[Claims] 1. A switch slave station connected to the switch slave station only during a test of a switch slave station for controlling a switch attached to a switch of a power system such as a division switch, and is connected to the switch slave station from the power system. A switch-slave station tester for testing the switch slave station, which is operated by being fed with a single-phase 3-wire control power source taken out via a cable, and which is connected to a terminal part of the control power source of the switch slave station through a cable. A power receiving terminal portion having a three-terminal configuration to be connected; voltage detecting means for detecting whether or not the voltage between the remaining two terminals other than the neutral terminal of the power receiving terminal portion is a proper voltage based on normal cable connection; A switch slave station tester comprising: a power supply control unit that closes a power supply path between the power receiving terminal unit and a load side circuit unit only when the voltage detection unit detects the appropriate voltage. .