JPH07294562A - Monitoring apparatus of distribution line - Google Patents

Abstract

PURPOSE:To obtain a monitoring apparatus in which a signal processing circuit is compatible with other optical sensors and which can quickly deal with a fault by installing a terminal, for electrical connection, which is installed at one end of a board inside a case, and an optical fiber cable one end of which is connected to a detection circuit installed on the board and the other end of which is connected to an optical sensor. CONSTITUTION:A screw is installed on the inner circumference of a container which protrudes from an end plate 23a, and an electric terminal 22a is formed on a board 22 by a printed-wiring operation or the like. Optical sensors 2 (3), drive circuits 10, E/O converters 12 and detection circuits 11 are connected by optical fibers. At this stage at which they have been connected, the magnitude of a gap in a ringed core or an irregularity in a sensitivity due to a change in the electrostatic capacity of a capacity voltage divider is adjusted by operating an adjusting screw for a variable amplifier 15 from a hole which has been made in the end part of a case, and the output sensitivity of the respective optical sensors 2 (3) is made identical. In addition, a signal processing circuit 16 adjusts the output sensitivity of a zero-phase current or a zero-phase voltage by operating an amplifier 18 in combination with a reference optical sensor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distribution line monitoring device for measuring current and voltage of a distribution line using an optical sensor.

[0002]

2. Description of the Related Art As shown in FIGS. 4 and 5, an optical system current sensor 2 and an optical system voltage sensor 3 are installed on a distribution line 1 for optical system current detection on a distribution line. The optical current sensor 2 is provided with an annular core 4 having a gap 4a, and a magnetic field sensor 5 including a polarizer, an electro-optic crystal element, and an analyzer in the gap.
Is arranged to measure the current of the distribution line, and the optical voltage sensor 3 has a capacitor voltage divider 6 for utilizing the stray capacitance installed on the distribution line, and two conductors 6a of the voltage divider are provided. 6b is connected to a voltage sensor 7 including a polarizer, an electro-optic crystal element, an analyzer and a wave plate. The detection signals of the optical sensors 2 and 3 composed of such optical type current sensors or optical type voltage sensors are transmitted through the optical fiber cable 8 to the light emitting element drive circuit 10, the E / O converter 12, the detection circuit 11 and the signals. It is configured to connect to an optical cable connector provided on one circuit board 9 having the processing circuit 16 to send and receive an optical signal. The drive circuit 10 is mounted on the circuit board so that the current flowing through the light emitting element is constant. The E / O converter 12 inputs the signal of the drive circuit and converts an electric signal into an optical signal. Detection circuit 1
1 transmits the optical signal of the E / O converter to the optical sensors 2 and 3 via the optical fiber cable 8, receives the optical signal from the optical sensor via the optical fiber cable, and converts the optical signal into an electric signal. E / O converter 13 and an automatic gain control circuit 14 for controlling the amplification factor of an electric signal corresponding to the measurement signal
And a variable amplifier 15 for inputting a signal from the automatic gail control circuit to adjust variations in optical sensor characteristics of an optical current sensor or an optical voltage sensor. The signal processing circuit 16 adds the detection signals detected from the respective phases R, S, T of the distribution line and amplified by the variable amplifier 15 to calculate a zero-phase current or zero-phase voltage, and an adder 17 from this adder. 18 that variably amplifies the signal of FIG. 1, a filter 19 that inputs the signal from this amplifier and extracts the fundamental wave component of the signal, and an A / D conversion circuit 20 that converts the analog signal from this filter into a digital signal. And A
The control circuit 21 performs effective value calculation of the signal from the / D conversion circuit or controls the signal processing circuit and communicates with the outside. In the distribution line monitoring device configured as described above, each optical sensor and the circuit board are coupled by an optical cable at the manufacturing stage, a signal is applied to adjust the amplification factor of the variable amplifier 15 of the detection circuit 11 of the optical sensor, and the The detection sensitivity of the sensor is adjusted, and the signal processing circuit 1
The amplifier 18 of 6 is adjusted to calibrate the zero-phase current and zero-phase voltage calculated by the adder 17. The optical sensors of the distribution line monitoring device adjusted in this way are attached to each phase of the distribution line, and a storage box (not shown) containing a circuit board is attached to a utility pole or the like, and the distribution line current, voltage, zero-phase current or The zero-phase voltage is detected.

[0003]

In such a distribution line monitoring device, a change in the current detection sensitivity between the phases of the optical sensor or a location where the optical sensor is mounted or a mounting location, for example, a location near a building or a location where trees are approaching, is used. A residual voltage is generated due to a change in stray capacitance. Therefore, the distribution line monitoring device malfunctions or the detection accuracy decreases. In addition, each optical sensor and the detection circuit cannot be adjusted individually, and both the optical sensor and the detection circuit on the circuit board of the storage box must be adjusted integrally. Further, even if an abnormality occurs in the photosensor for only one phase for some reason, the set is for three phases, so that both the photosensor and the circuit board must be replaced. An object of the present invention is to provide a detection circuit of an optical sensor on the other end of an optical fiber connected to the optical sensor so that the optical sensor can be adjusted by itself.

[0004]

In order to achieve the above object, the present invention, as a first device, installs an optical current sensor or voltage sensor on a distribution line to detect the current or voltage of the distribution line. In the distribution line monitoring device, a board on which a drive circuit, an E / O converter, an O / E converter, a detection circuit including a control circuit and a variable amplifier are mounted and printed, and a case for housing the board are provided. A terminal for electrical connection provided in one end of the substrate in the case and an optical fiber cable having one end connected to a detection circuit provided in the substrate and the other end connected to an optical sensor are provided. As a second device, a board on which a drive circuit, an E / O converter, an O / E converter, a control circuit and a detection circuit composed of a variable amplifier are mounted and printed, a case for accommodating the board, and a case Inside, there is a terminal for electrical connection provided at one end of the substrate, an optical fiber that has one end connected to the detection circuit provided on the substrate and the other end is connected to the optical sensor, and adjustment of the variable amplifier for adjusting the optical sensor sensitivity. A hole is provided in the case end plate at a position corresponding to the screw.

[0005]

According to the above means, each optical sensor can adjust the variable amplifier of the detection circuit connected through the optical fiber cable independently to adjust the sensor sensitivity at the manufacturing stage of the distribution line monitoring device.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. 1 is a circuit configuration diagram of a distribution line monitoring device, FIG. 2 is a front view of a connector, and FIG. 3 is a sectional view of the connector. The same parts as those in FIG. 4 are designated by the same reference numerals and detailed description thereof will be omitted. 22 is a substrate, which is an E / O converter 1
2, the detection circuit 11 including the O / E converter 13, the automatic gain control circuit 14 and the variable amplifier 15 and the drive circuit 10 are mounted, and the components are connected by printed wiring. The substrate thus constructed is housed in the connector case 23 and fixed to the end plate 23a of the container case as shown in FIGS. A screw 23b is provided on the inner circumference of the container protruding from the end plate.
Is provided, and the electric terminal 2 is provided on the substrate 22 protruding from the end plate.
2a is formed by a printed wiring or the like. The optical cable 8 is inserted from the other side of the case, the optical cable is fixed to the case with a clasp or the like, and the optical cable is connected to the E / O converter 12 or the O / E converter 13. A hole 23c is formed in the end plate 23a of the case, and the adjusting screw 15a of the variable amplifier 15 is seen in this hole. A circuit board 24 is a signal processing circuit 16 including an adder 17, an amplifier 18, a filter 19, an A / D converter 20 and a controller 21.
Is mounted, and the components are printed and connected to each other to be configured and housed in a detection box (not shown). 25 is the substrate 2
It is an electric wire that electrically connects 1 and the circuit board 24 with a connector. The optical sensor, the drive circuit, the E / O converter, and the detection circuit of the distribution line monitoring device configured as described above are connected by an optical fiber, and at this connection stage, the size of the annular core gap or the capacitor voltage divider is connected. By adjusting the adjustment screw of the variable amplifier through the hole provided in the end plate of the case, the variation of the sensitivity due to the change of the electrostatic capacitance is adjusted so that the output sensitivity of each optical sensor becomes the same.
Further, the signal processing circuit operates the amplifier in combination with the reference optical sensor to adjust the output sensitivity of the zero phase current or the zero phase voltage.

[0007]

As described above, according to the present invention, since the optical sensor is provided with the adjusting function, it is possible to provide compatibility with other optical sensors and the signal processing circuit. Even if an abnormality occurs in the back light sensor, it is possible to quickly and easily deal with the failure by replacing only the light sensor. Also, since the connection part is electrically connected,
The effect that the handling is easier than the connection by the conventional optical connector is obtained.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram of a distribution line monitoring device showing an embodiment of the present invention.

FIG. 2 is a front view of the connector of FIG.

FIG. 3 is a side sectional view of FIG.

FIG. 4 is a circuit configuration diagram of conventional distribution line monitoring.

FIG. 5 is a schematic diagram of a current / voltage detection device using an optical sensor.

[Explanation of symbols]

 1 Distribution line 2 Optical system current sensor 3 Optical system voltage sensor 8 Optical fiber cable 10 Driving circuit 11 Detection circuit 12 E / O converter 13 O / E converter 14 Control circuit 15 Variable amplifier 16 Signal processing circuit 17 Adder 18 Amplifier 19 Filter 20 A / D Converter 21 Control Circuit 22 Board 22a Terminal 23 Case 23a End Plate 23c Hole 24 Board 25 Electric Wire

Claims (2)

[Claims] 1. A distribution line monitoring device in which an optical current sensor or voltage sensor is installed on a distribution line to detect the current or voltage of the distribution line, a drive circuit, an E / O converter, and an O / E converter, A board on which a control circuit and a detection circuit composed of a variable amplifier are mounted and printed, a case for housing the board, a terminal for electrical connection provided in one end of the board in the case, and one end on the board An optical fiber having an optical fiber connected to the detection circuit provided and having the other end connected to an optical sensor. 2. A distribution line monitoring device for installing an optical current sensor or voltage sensor on a distribution line to detect the current or voltage of the distribution line, a drive circuit, an E / O converter, and an O / E converter, A board on which a control circuit and a detection circuit composed of a variable amplifier are mounted and printed, a case for housing the board, a terminal for electrical connection provided in one end of the board in the case, and one end on the board An optical fiber connected to the provided detection circuit and connected to the optical sensor at the other end, and a hole provided in the case end plate at a position corresponding to the adjusting screw of the variable amplifier for adjusting the optical sensor sensitivity are provided. Distribution line monitoring device