JPH09281151A - Voltage sensor - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To efficiently separate a voltage / current conversion circuit that processes a high voltage and a current value measurement circuit that processes a low voltage,
The electrical insulation between them is ensured, which facilitates the work of designing the circuit board and downsizes the entire sensor. SOLUTION: A board body 7 on the high voltage side circuit board 3 side is fixed on a high voltage side bobbin 14 constituting a magnetic transformer 4, and a low voltage side circuit is arranged on a low voltage side bobbin 15 constituting the magnetic transformer 4. The substrate main body 21 on the substrate 5 side is fixed, and a voltage / current conversion circuit or the like for processing a high voltage and a current value measuring circuit or the like for processing a low voltage are efficiently separated for each substrate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voltage sensor which takes in a voltage to be measured, converts this measured voltage into a voltage / current, measures the value of this current, and judges the value of the measured voltage. Regarding

[0002]

2. Description of the Related Art Voltage to be measured (hereinafter, measured voltage)
As a voltage sensor that takes in the voltage and current and measures the magnitude of the secondary current obtained by the voltage / current conversion operation by the zero magnetic flux method (servo type) or the magnetic flux measurement method. The one shown in FIG. 6 is known.

A voltage sensor 101 shown in this figure has first and second input terminals 102 and 103 for receiving a measured voltage, and voltage / current conversion of the measured voltage input to these first and second input terminals 102 and 103. A voltage / current conversion circuit 104 for generating a primary current, a magnetic transformer 105 for generating a secondary current corresponding to the primary current generated by the voltage / current conversion circuit 104, and a magnetic transformer 105 By the zero magnetic flux method (servo type) using the provided magnetic sensor 106, a compensating current corresponding to the secondary current obtained by the magnetic transformer 105 is generated, and the compensating current is generated.
05, and a current value measuring circuit 107 for determining the magnitude of the measured voltage.

One end of the voltage / current conversion circuit 104 is the first
Drop resistor 108 connected to the input terminal 102
And a drop resistor 109 having one end connected to the other end of the resistor 108, and the first and second input terminals 10
The measurement voltage input to 2, 103 is taken in and the resistance 10
A primary current is generated while the measured voltage is dropped by 8, 109, and this is supplied to the magnetic transformer 105.

The magnetic transformer 105 is formed in a square shape with a slit in a part thereof and a magnetic core 110 made of a high magnetic permeability material, and the magnetic transformer 105.
Which is wound around the high-voltage side bobbin constituting the magnetic core 1 according to the primary current output from the voltage / current conversion circuit 104.
A primary winding 111 for generating a magnetic flux in the coil 10, and a secondary winding 112 wound around a low voltage side bobbin constituting the magnetic transformer 105 and in which a secondary current is induced by the magnetic flux generated in the magnetic core 110. , A magnetic sensor 106 that is fitted into the slit of the magnetic core 110 and detects the magnetic flux density in the magnetic core 110. When the primary current is supplied from the voltage / current conversion circuit 104, the primary winding Line 1
A magnetic flux is generated in the magnetic core 110 by 11
A secondary current is induced in the secondary winding 112 and is supplied to the current value measuring circuit 107, and the current value measuring circuit 1
The magnetic flux generated in 07 and generated in the secondary winding 112 generates a magnetic flux in the magnetic core 110 in the opposite direction to the magnetic flux generated by the primary winding 111.

In parallel with this operation, the magnetic sensor 1
The magnetic flux density in the magnetic core 110 is detected by 06, and the magnetic flux density detection signal obtained by this detecting operation is supplied to the current value measuring circuit 107.

The current value measuring circuit 107 includes a secondary winding 112.
Load resistance 113 that receives a secondary current output from the magnetic sensor 106, an operational amplifier 114 that amplifies the magnetic flux density detection signal output from the magnetic sensor 106, and two serially connected between the constant voltage line and the ground point. Output transistors 115, 1
16 and includes an amplifier circuit 117 that amplifies the magnetic flux density detection signal output from the operational amplifier 114 to generate a compensation current and supplies the compensation current to one end of the secondary winding 112. While receiving the secondary current output from the secondary winding 112, the compensating current in the current direction opposite to the current direction of the secondary current is generated based on the magnetic flux density detection signal output from the magnetic sensor 106. It is generated and supplied to the secondary winding 112.

Then, based on the compensation current value when the magnetic flux in the magnetic core 110 indicated by the magnetic flux density detection signal output from the magnetic sensor 106 becomes zero, the magnetic transformer 10
The magnitude of the secondary current output from 5 is determined, and a signal indicating the value of the measured voltage is generated based on the determination result.

A mounted state of the voltage sensor 101 shown in FIG. 6 is shown in FIG. As shown in the figure, one circuit board 12
0 to the voltage / current conversion circuit 104 and the current value measurement circuit 10
7, a plurality of electronic components 121 are arranged, the magnetic transformer 105 is fixed to the back surface of the circuit board 120, and a high voltage input line 122 is used to apply a measurement voltage (for example, a voltage of several hundreds of volts) to the circuit board. The measurement result obtained by the current value measurement circuit 107 is output to the harness side or the like via the low voltage circuit input / output line 123 while being guided to the voltage / current conversion circuit 104 on 120.

[0010]

However, in the above-mentioned conventional voltage sensor 101, the resistor 108 of the voltage / current conversion circuit 104 arranged on the circuit board 120,
Since the input voltage of 109 is as high as several hundreds of V, it is necessary to use a large amount of electric power. Therefore, the circuit board 12 is used as an arrangement space for these resistors 108 and 109.
There is a problem in that the circuit board 120 becomes large correspondingly because it is necessary to secure a large area space above 0.

Further, since the voltage / current conversion circuit 104 for processing a high voltage and the current value measuring circuit 107 for processing a low voltage are arranged on one circuit board 120, these voltage / current conversion circuits 104 are arranged. And electrical insulation between the current value measuring circuit 107 that processes low voltage and Therefore, these voltage / current conversion circuits 104
Then, there has been a problem that a certain distance from the current value measuring circuit 107 that processes the low voltage must be secured, and an extra space is required accordingly.

Further, since the voltage / current conversion circuit 104 for processing a high voltage and the current value measuring circuit 107 for processing a low voltage are arranged on one circuit board 120, the circuit board 120 is made of a substrate material. Are two circuits 104, 1
There has been a problem that an expensive material that satisfies both of the characteristics of 07 must be used, and there is much waste in terms of cost.

The present invention has been made in view of the above circumstances, and an object thereof is to efficiently separate a voltage / current conversion circuit for processing a high voltage and a current value measuring circuit for processing a low voltage. An object of the present invention is to provide a voltage sensor which can ensure electrical insulation between them, which can facilitate the design work of a circuit board and can downsize the entire sensor.

[0014]

In order to achieve the above object, the present invention has a high voltage side bobbin, a low voltage side bobbin, and a magnetic transformer having a magnetic core penetrating the centers of both bobbins. A high-voltage side circuit board having at least a function of converting a voltage to be measured into a voltage / current is fixed to the side, and a low-voltage side bobbin side has at least a function of determining a value of the voltage to be measured. A low-voltage circuit board, which is provided separately from the high-voltage circuit board, is fixed.

With the above configuration, a magnetic transformer is configured in the voltage sensor that takes in the measured voltage, converts the voltage / current, measures the value of the current obtained thereby, and determines the value of the measured voltage. By fixing the high-voltage side substrate to the high-voltage side bobbin side and fixing the low-voltage side substrate to the low-voltage side bobbin side that constitutes the magnetic transformer, a low-voltage and voltage-current conversion circuit that processes high voltage can be obtained. The current value measuring circuit to be processed is efficiently separated to ensure electrical insulation between them, which facilitates the design work of the circuit board and downsizes the entire sensor.

[0016]

1 is a side view showing an embodiment of a voltage sensor according to the present invention.

The voltage sensor 1 shown in this figure outputs a high voltage side circuit board 3 for processing a measurement voltage when the measurement voltage is input through the high voltage input line 2 and the high voltage side circuit board 3. The magnetic transformer 4 for generating a secondary current according to the primary current, and the secondary current output from the magnetic transformer 4 are taken in, and a compensating current is generated and supplied to the magnetic transformer 4. Is measured, and based on this measurement result, the magnitude of the measured voltage is determined,
It is provided with a low voltage side circuit board 5 which supplies this to the harness side or the like via a low voltage circuit input / output line 6.

The high-voltage side circuit board 3 is a board body 7 made of a board material for high voltage, and, as shown in FIG. 2, of the surfaces of the board body 7 on the side opposite to the magnetic transformer 4. Disposed on the surface, the first input terminal, the second input terminal,
It is provided with a plurality of high-voltage side electronic components 8 which are constituent elements such as resistors of the voltage / current conversion circuit, and takes in the measured voltage supplied via the high-voltage input line 2 to obtain high-voltage side electronic components 8 The measured voltage is processed to generate a primary current, which is supplied to the primary winding 9 of the magnetic transformer 4.

The magnetic transformer 4 has a U-shaped magnetic core 10 formed by combining two U-shaped members made of a high magnetic permeability material in a state where a slit is provided, and one side of the magnetic core 10. High voltage for fixing the board main body 7 constituting the high voltage side circuit board 3 by the screw 13 screwed into the prepared hole 12 formed in the boss 11 as shown in FIG. The side bobbin 14 and, as shown in FIG. 4, the magnetic core 1 is wound around the high-voltage side bobbin 14 according to the primary current output from the high-voltage side circuit board 3.
The primary winding 9 for generating a magnetic flux in 0, the low-voltage side bobbin 15 which is incorporated and fixed to the other side of the magnetic core 10, and the low-voltage side bobbin 15 are wound on the low-voltage side bobbin 15 and Secondary winding 1 in which a secondary current is induced by the generated magnetic flux
6 and embedded in the magnetic core 10,
And a magnetic sensor 17 for detecting the magnetic flux density therein.

When a primary current is supplied from the high voltage side circuit board 3, a magnetic flux is generated in the magnetic core 10 by the primary winding 9 to induce a secondary current in the secondary winding 16. , Which is supplied to the low voltage side circuit board 5 and is generated by the primary winding 9 in the magnetic core 10 by the compensation current output from the low voltage side circuit board 5 and flowing in the secondary winding 16. Generates a magnetic flux in the opposite direction to the magnetic flux.

In parallel with this operation, the magnetic sensor 1
The magnetic flux density in the magnetic core 10 is detected by 7 and the magnetic flux density detection signal obtained by this detecting operation is supplied to the low voltage side circuit board 5.

The low-voltage side circuit board 5 is made of a low-voltage board material, and is in contact with each boss 18 of the low-voltage side bobbin 15 constituting the magnetic transformer 4, as shown in FIG. As shown in FIG. 5, a substrate body 21 fixed to the low-voltage side bobbin 15 by screws 20 screwed into prepared holes 19 formed in these bosses 18;
As shown in FIG. 3, a plurality of low-voltage side electronic components 22 that are arranged on one of the surfaces of the substrate body 21 facing the magnetic transformer 4 and serve as a component such as a current value measuring circuit are provided. A current direction that is opposite to the current direction of the secondary current based on the magnetic flux density detection signal output from the magnetic sensor 17 while receiving the secondary current output from the secondary winding 16 of the magnetic transformer 4. Is generated and is supplied to the secondary winding 16.

The magnitude of the secondary current output from the magnetic transformer 4 is based on the compensation current value when the magnetic flux in the magnetic core 10 indicated by the magnetic flux density detection signal output from the magnetic sensor 17 becomes zero. Is output to the harness side or the like via the low voltage circuit input / output line 6 as a signal indicating the voltage value of the measured voltage. Further, the voltage sensor may be in the form of current output not including the load resistor 113 shown in FIG.

As described above, in this embodiment,
The board body 7 on the high voltage side circuit board 3 side is fixed on the high voltage side bobbin 14 forming the magnetic transformer 4, and the low voltage side circuit board 5 side on the low voltage side bobbin 15 forming the magnetic transformer 4. Since the substrate body 21 is fixed, the voltage / current conversion circuit or the like for processing the high voltage and the current value measuring circuit or the like for processing the low voltage can be efficiently separated on a substrate unit basis. It is possible to ensure electrical insulation between the high-voltage side circuit and the low-voltage side circuit, and at the time of designing the high-voltage side circuit board 3, without considering the state of the low-voltage side circuit board 5. Ok,
Further, when designing the low-voltage side circuit board 5, it is not necessary to consider the state of the high-voltage side circuit board 3, so that the design work of the circuit board can be facilitated.

Further, since the high voltage side circuit board 3 and the low voltage side circuit board 5 may be arranged at any angle with the magnetic core 10 as the center, they are arranged at right angles. Alternatively, by arranging them in parallel, the space occupied by the voltage sensor 1 itself can be reduced and the overall size of the sensor can be reduced.

[0026]

As described above, according to the present invention, the voltage / current conversion circuit for processing a high voltage and the current value measuring circuit for processing a low voltage are efficiently separated from each other, and the electrical connection therebetween is provided. Insulation can be ensured, which facilitates the work of designing the circuit board and can downsize the entire sensor.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of a voltage sensor according to the present invention.

FIG. 2 is a top view showing an example of a connection relationship between the high voltage circuit board shown in FIG. 1 and a magnetic sensor.

FIG. 3 is an enlarged view of a main part of an example of the connection relationship between the high voltage circuit board shown in FIG. 1 and a magnetic sensor.

FIG. 4 is a rear view showing an example of the connection relationship between the low voltage circuit board shown in FIG. 1 and a magnetic sensor.

5 is an enlarged view of an essential part of an example of the connection relationship between the low voltage circuit board shown in FIG. 1 and a magnetic sensor.

FIG. 6 is a circuit diagram showing an example of a conventionally known voltage sensor.

FIG. 7 is a side view showing a mounted state of the voltage sensor shown in FIG.

[Explanation of symbols]

 1 Voltage Sensor 2 High Voltage Input Line 3 High Voltage Side Circuit Board 4 Magnetic Transformer 5 Low Voltage Side Circuit Board 6 Low Voltage Circuit Input / Output Line 7 Board Body 8 High Voltage Side Electronic Components 9 Primary Winding 10 Magnetic Core 11 Boss 12 Pilot Hole 13 screw 14 high voltage side bobbin 15 low voltage side bobbin 16 secondary winding 17 magnetic sensor 18 boss 19 prepared hole 20 screw 21 board body 22 low voltage side electronic component

Claims (1)

[Claims] 1. A magnetic transformer having a high-voltage side bobbin, a low-voltage side bobbin, and a magnetic core penetrating the centers of both bobbins, and the high-voltage side bobbin side is provided with a voltage to be measured.
A high-voltage side circuit board having at least a function of converting current is fixed, and the low-voltage side bobbin side has at least a function of determining the value of the voltage to be measured and is separate from the high-voltage side circuit board. A voltage sensor characterized in that the constructed low-voltage side circuit board is fixed.