JPH11326425A - Polarity inversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a rapid and stable polarity inversion action of a high voltage by constituting a device comprising a glass having three electrode terminals and in which the terminal at a load side rotates and has a switching terminal bar at a tip end. SOLUTION: A polarity inversion device is constituted by fixed glasses 6, 7 equipped with two terminals receiving a voltage from direct current high pressure generating power sources 1, 2 having a positive polarity and a negative polarity respectively; and a rotating driving glass 8 equipped with one switching terminal having a switching terminal bar 9 tightening a terminal feeding a voltage to a load side with a positive polarity or negative polarity terminal. Then, the switching terminal bar 9 is swung by operating a rotating driving motor and is operated such that the terminal at a tip end of the switching terminal bar 9 switch-contacts with the positive polarity or negative polarity terminal. Therefore, according to the polarity inversion device, a high voltage polarity inversion test can be carried out to a direct current transmission cable or an instrument. Further, switching is carried out in a short time of several hundreds msec. to several seconds and a waveform having no damping is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polarity reversing device for alternately receiving two positive or negative DC voltages,
In particular, it relates to this type of polarity reversing device used for testing power cables and equipment.

[0002]

2. Description of the Related Art In power cables and equipment for DC transmission, it is necessary to verify the performance against reversal of power flow and intrusion of reverse polarity surge during operation, so that the polarity changes from positive to negative or negative to positive. A charging test is performed in which the voltage is switched in a short time.

[0003] For the above-mentioned power application test, two DC high voltage generators of positive polarity and negative polarity are used to alternately apply a voltage to a test sample (load). The voltage is applied by reversing the direction of the diode in the generation power supply.

[0004] In the above test, a short time (several seconds)
To switch the polarity, without going through the ground on the way,
In order to apply voltages having different polarities to the sample, the former method is often used. This former method is as simple as shown in FIG. 7 when shown in an electric circuit diagram. In FIG. 7, 1 indicates a positive DC power source, 2 indicates a negative DC power source, 3 indicates a test sample (cable), and 4 indicates a polarity reversing device.

[0005]

According to the above-mentioned prior art; according to the polarity reversing device as shown in FIG. 7, a space distance for insulating a high voltage is required for polarity reversal of a high voltage of several tens kV or more. Therefore, since the size of the apparatus itself is increased, a polarity switching operation by remote control has been required. In remote control of such a large-sized device, it tends to be difficult to supply the switching waveform quickly and stably to supply the switching waveform.

Therefore, the problems to be solved by the present invention (objects)
It is an object of the present invention to provide a polarity reversing device capable of quickly and stably supplying a high-voltage polarity reversing operation to a switching waveform.

[0007]

The polarity reversing device provided by the present invention receives a voltage from two DC high voltage power supplies of positive polarity and negative polarity, and switches the voltage between the positive and negative polarities to the test sample. In the supplied polarity reversing device, an insulator having three electrode terminals; a positive terminal, a negative terminal, and a load terminal; the load terminal rotates, and a switching terminal rod at the tip; and a contact rod. Things.

In a preferred embodiment, an elastic rod (fiber rod, carbon fiber rod) is used for the switching terminal rod, which is effective as a measure for preventing damping at the time of voltage switching.

It is preferable that a spring is attached to a portion where the switching terminal rod of the positive terminal and the negative terminal contacts.

Further, it is preferable that a rotating ring is provided in the sample side voltage supply section of the load side terminal. This is good for preventing the lead wire to the load from rotating even if the load side terminal rotates. By using a contact having a spring for the rotating ring, the voltage supply can be stabilized.

It is preferable that a balancer is disposed above the load-side terminal. This is effective in preventing the rotation drive insulator from swinging due to the rotation operation of the load side terminal.

It is preferable that an insulation pulley is provided in the rotation drive section of the load side terminal to insulate the drive motor and the power application section. This is effective for protecting the drive control unit against a surge generated at the time of polarity inversion.

[0013]

1 to 6 show a preferred embodiment of a polarity reversing device according to the present invention.
Shows the basic concept of the polarity reversing device, FIG. 2 shows the structure of the fixed insulator and the rotary drive insulator, FIG. 3 shows the structure of the contact portion between the fixed terminal and the switching terminal on the fixed insulator, and FIG. 5 shows the structure of the load-side terminal, and FIG. 5 shows the structure of the rotary pulley.

The polarity reversing device of this embodiment has two fixed insulators with terminals for receiving voltages from DC high voltage generating power supplies 1 and 2 of positive and negative polarities, respectively, as indicated by reference numeral 4 in FIG. , 7 and one of the rotary drive type insulators 8 having a switching terminal having a switching terminal rod 9 connecting a terminal for supplying voltage to the load side and a positive or negative terminal.
In FIG. 1, reference numeral 3 denotes a test sample (cable), and reference numeral 5 denotes a lead wire connecting the terminal to the power supply 1 or 2 or the terminal to the test sample (cable) 3.

In FIG. 2 specifically showing the structure of the fixed insulators 6, 7 and the rotary drive type insulator 8, 10 is a post insulator, 11 is a shield, 12 is a base stand, 13 is a bar, 14 is a balancer, Reference numeral 15 denotes a contact portion between the fixed terminal and the switching terminal on the upper part of the fixed insulator, 16 denotes a contact rotating ring, 17 denotes a drive motor, and 18 denotes a rotary pulley.

The number of the post insulators 10 to be connected may be determined according to the magnitude of the DC high voltage, and the insulator material may be ceramic or polymer. An elastic rod; a fiber rod or a carbon fiber rod is used for the switching terminal rod 9, and an electric wire connecting the tip terminal and the load side terminal may be wired around the rod. With the use of such elastic rods,
It is possible to suppress an impact when the switching terminal rod 9 contacts the positive or negative terminal.

In the above-described structure, by operating the rotary drive motor 17, the switching terminal rod 9 is swung so that the terminal at the tip of the switching terminal rod 9 switches to the positive or negative terminal. It is operated to be. The balancer 14 and the suspension rod 13 are the switching terminal rod 13
It helps to prevent run-out and droop due to the rotation of.
The contact rotating ring 16 is for allowing the rotation of the rotary drive insulator during the switching operation to take out the load-side terminal from the rotary unit (the rotary drive insulator is rotated during the switching operation, so that the rotary drive insulator is directly rotated from the rotary unit. If the load side terminal is taken out, the load side terminal will rotate together.) In short, this is for causing the terminal portion of the load side terminal 8 to perform relative rotation.

The structure in FIG. 3 which specifically shows the contact portion 15 between the fixed terminal on the positive and negative sides and the switching terminal on the load side has a plurality of springs 20 arranged at the terminal above the fixed insulator. The contact 20 is brought into contact with the terminal 19 on the distal end of the switching terminal rod so that the contact is complete and the impact at the time of contact is further suppressed. The spring 20 is disposed between the upper and lower shield rings 11, 11 on the entire circumference, so that the switching terminal rod 9 (terminal 19) can be arranged without worrying about the arrangement direction of the fixed insulator.
Contact is possible.

A load-side terminal on the load-side rotary drive insulator;
In FIG. 4 specifically showing the structure of the contact rotating ring 16, the load-side terminal fitting 21 rotated by the bearing 22 is shown.
In order to ensure contact with the load-side terminal fitting 21, a contact 24 having a spring 26 is provided in the rotation drive unit 23. With this structure, the lead wire connected to the load-side terminal fitting 21 is prevented from being rotated by the rotation of the insulator, and voltage and current can be supplied without any problem. Incidentally, reference numeral 26 denotes a lead phosphor bronze.

When switching the polarity of a high voltage, the operation of the control device may fail due to the generation of a surge voltage. In this embodiment, the insulator is rotationally driven by a drive motor 17 as shown in FIG. 2. However, in order to prevent a surge from entering the control unit of the drive motor 17, a pulley 18 of the drive unit is used as shown in FIG. A structure in which a plastic ring 28 is incorporated in a metal pulley main body 27 as shown is adopted to insulate the motor section from the rotary drive insulator ground section.

As a power application test using the polarity reversing device of the present embodiment having the above-described structure, a power cable; 66 kVC cable is applied to a test sample, and V = ± 250 kV
Was performed. FIG. 6 shows data of the voltage waveform at that time. As is apparent from FIG. 6, it is understood that a waveform of almost ideal polarity inversion is obtained.

The polarity switching time according to the present embodiment is determined by the setting of the rotation speed of the rotary drive motor 17,
Short-time switching on the order of several hundred milliseconds to several seconds is possible.

According to the polarity reversing device of this embodiment, it is possible to carry out a high voltage polarity reversal test on a DC transmission cable or a device, and to perform short-time switching on the order of several hundred milliseconds to several seconds without damping. A waveform is obtained.

[0024]

According to the present invention as described above, the intended problem (object) is to provide a polarity inversion device capable of promptly and stably supplying a high-voltage polarity inversion operation to a stable switching waveform. Can be achieved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a basic concept of a polarity reversing device according to an embodiment of the present invention.

FIG. 2 is an explanatory view showing a specific structure of a fixed insulator with positive and negative terminals and a rotary drive insulator with a load side terminal in the apparatus of FIG. 1;

FIG. 3 is an explanatory view specifically showing a structure of a contact portion 15 between a fixed terminal on a fixed insulator and a switching terminal in the device of FIG. 1;

FIG. 4 is an explanatory view specifically showing the structure of a load side terminal; contact rotating ring 16 in the apparatus of FIG. 1;

FIG. 5 is an explanatory diagram specifically showing the structure of a rotary pulley 18 in the apparatus shown in FIG.

FIG. 6 is a graph showing polarity inversion waveform data when a power application test is performed using the polarity inversion device of FIG. 1;

FIG. 7 is an explanatory diagram of a polarity reversal test circuit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Positive DC power supply 2 Negative DC power supply 3 Test sample (cable) 4 Polarity reversing device 5 Lead wire 6 Fixed insulator with terminal (for positive polarity) 7 Fixed insulator with terminal (for negative polarity) 8 Rotation with switching terminal rod Driving insulator (with load side terminal) 9 Switching terminal rod 10 Post insulator 11 Shield 12 Base stand 13 Suspension rod 14 Balancer 15 Contact portion between fixed terminal and switching terminal 16 Contact rotating ring (Load side terminal) 17 Drive motor 18 Rotary pulley DESCRIPTION OF SYMBOLS 19 Terminal part of switching terminal rod tip 20 Spring 21 Load side terminal fitting 22 Bearing 23 Rotation drive part 24 Contact 25 Spring 26 Phosphor bronze 27 Metal pulley 28 Plastic ring

Claims (7)

[Claims] 1. A polarity reversing device for receiving a voltage from two DC high-voltage generating power supplies of positive and negative polarities and supplying the voltage to a test sample alternately with positive or negative polarity and having three electrode terminals. Insulator: A polarity reversing device comprising a positive terminal, a negative terminal, and a load terminal, wherein the load terminal rotates and a switching terminal rod is provided at the tip; 2. The polarity reversing device according to claim 1, wherein an elastic rod (fiber rod, carbon fiber rod) is used as the switching terminal rod. 3. A spring is attached to a portion where the switching terminal rod of the positive terminal and the negative terminal contacts with each other.
A polarity reversing device as described. 4. The polarity reversing device according to claim 1, wherein a rotating ring is provided in the sample-side voltage supply section of the load-side terminal. 5. The polarity reversing device according to claim 4, wherein a contact having a spring is used for said rotating ring. 6. The polarity reversing device according to claim 1, wherein a balancer is arranged above the load-side terminal. 7. The polarity reversing device according to claim 1, wherein an insulated pulley is provided on a rotary drive section of said load-side terminal, and the drive motor and the power application section are insulated.