CN105259501B - A kind of high voltage direct current cut-offs experimental provision - Google Patents

Abstract

The invention discloses a high-voltage direct current breaking experiment device. The experiment device includes a device body, and static arc contacts and moving arc contacts are arranged up and down inside the device body. The experiment device also includes driving the dynamic and static arc contacts to carry out For the operating mechanism for opening and closing, the static arc contacts and the moving arc contacts are respectively connected with voltage application terminals, and the outer side wall of the device body is provided with the static arc contacts and the moving arc contacts to observe the generation of the static arc contacts and the dynamic arc contacts during opening. viewing window for the arc. The high-voltage direct current breaking experiment device provided by the invention can simulate the opening and closing process of the moving arc contact and the static arc contact, and by changing the parameters of the operating mechanism that drives the moving arc contact, the moving speed of the moving arc contact can be changed. , you can observe the arc shape at different opening speeds through the observation window set on the device body, find out the occurrence rule of the arc, and further guide the optimal design of the switch structure.

Description

An experimental device for high voltage DC breaking

technical field

The invention relates to a high-voltage direct current breaking experiment device.

Background technique

In the HVDC transmission system, the conversion of certain operating modes and the removal of faults require the use of a DC transfer switch, and the DC current has no zero-crossing point, so the breaking of the DC current must be forced to cross zero. However, when the DC current is forced to cross zero, because the DC system stores a huge amount of energy to be released, the released energy will generate overvoltage on the circuit, causing the arc between the fractures to reignite, resulting in failure to break. The DC transfer switches used in the high-voltage DC converter stations built in my country are composed of three parts: 1. The transfer switch transformed from the AC circuit breaker; 2. The oscillation circuit for the purpose of forming the current zero-crossing point; 3. The An energy dissipation element for the purpose of absorbing the energy stored in the DC circuit. The cost of the oscillating circuit and the energy-consuming components is relatively high, and the structure of the existing DC transfer switch is complex, and the manufacturing and maintenance costs are relatively high. It is the development direction of high-voltage switches to improve the rapid breaking performance of high-voltage DC switches and reduce manufacturing costs. What factors restrict the breaking reliability of high-voltage switches still needs to be studied.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a high-voltage direct current breaking experiment device, which can analyze the data affecting the arc parameters, discover the occurrence rule of the arc, and further guide the optimal design of the switch structure.

In order to achieve the above purpose, the technical scheme of the high-voltage direct current breaking test device of the present invention is as follows: the high-voltage direct current interrupting experimental device includes a device body and a contact assembly located in the device body. A moving arc contact, the experimental device further includes an operating mechanism for driving the static arc contact and the moving arc contact to open and close, the device body has a cavity for the moving arc contact to move, so The static arc contacts and the moving arc contacts are respectively connected with voltage application terminals, and the static arc contacts and the dynamic arc contacts form a closed loop when they are closed by applying voltage to the voltage application terminals. Observation window for observing the arc generated by the static arc contact and the moving arc contact when the switch is opened.

The device body is provided with a measuring device for collecting the corresponding data of the arc.

The measuring device includes a measuring cover plate, a temperature sensor, and a gas pressure sensor, and the measuring cover plate is provided with a corresponding temperature sensor outlet end and a gas pressure sensor outlet end.

The device body is in the shape of a cylinder extending in the up-down direction, and a measuring cylinder is protruded radially on the side wall of the device body. The installation space of the sensor, the measurement cover is connected to the measurement cylinder.

The contact assembly consists of static arc contacts and moving arc contacts.

The operating mechanism is a motor-driven operating mechanism, and the motor-driven operating mechanism includes a servo motor and a transmission mechanism located between the servo motor and the moving arc contact.

The axis of the output shaft of the servo motor is perpendicular to the moving direction of the moving arc contact.

The device body is provided with an explosion-proof disc between the static arc contact and the moving arc contact.

Beneficial effects of the present invention: the high-voltage direct current breaking experiment device provided by the present invention can simulate the opening and closing process of the moving arc contact and the static arc contact, and by changing the parameters of the operating mechanism that drives the moving arc contact, it is possible to change the The moving speed of the moving arc contact can be used to observe the arc shape at different opening speeds through the observation window set on the device body, find out the occurrence rule of the arc, and further guide the optimal design of the switch structure.

Description of drawings

Fig. 1 is the structural representation of the embodiment of the high-voltage direct current breaking experiment device of the present invention;

Fig. 2 is the structural representation of the device body in Fig. 1;

FIG. 3 is a schematic structural diagram of the operating mechanism in the high-voltage direct current breaking experiment device of the present invention.

Detailed ways

An embodiment of a high-voltage DC disconnection experimental device of the present invention: as shown in Figures 1-3, the high-voltage DC disconnection experimental device includes a bracket 5 and a device body 6 arranged on the bracket 5, and the device body 6 extends in the up-down direction. The device body 6 is provided with a contact assembly. The contact assembly includes a static arc contact 8 and a moving arc contact 9 arranged up and down. The device body 6 has a cavity for the moving arc contact 9 to move. The experimental device also includes a motor-driven operating mechanism that drives the static arc contact 8 and the moving arc contact 9 to open and close. There are two voltage application terminals on the device body to make the static arc contact and the moving arc contact form a closed loop when closing, one is the voltage application terminal 1 located at the upper end of the device body, and the other is located on the side of the device body. Applied voltage terminal 3 on the wall. The outer side wall of the device body 6 is provided with an observation window 2 for observing the arc generated by the static arc contact 8 and the moving arc contact 9 when the switch is opened. The device body 6 is provided with an observation hole above the voltage application terminal. A cover plate 14 is installed on the outer end of the device, and the material of the cover plate 14 is acrylic, and the light transmittance reaches more than 90%, which can withstand the instantaneous pressure shock generated in the device body when the arc occurs. The shape of the arc can be photographed using a high-speed camera.

The device body 6 is provided with a measuring device for collecting the corresponding data of the arc on the opposite side of the voltage-applying end 3. The measuring device includes a measuring cover 13, a temperature sensor, and a gas pressure sensor. The measuring cover 13 is provided with corresponding The temperature sensor outlet 11 and the gas pressure sensor outlet 12. A measuring cylinder 10 is protruded radially on the side wall of the device body 6 . The measuring cylinder 10 has an installation space for placing a temperature sensor and a gas pressure sensor that communicates with the cavity of the device body. The measuring cover plate 13 is connected to the measuring cylinder 10 . superior.

The operating mechanism is a motor-driven operating mechanism, and the motor-driven operating mechanism includes a servo motor 4 and a transmission mechanism located between the servo motor 4 and the moving arc contact. The transmission mechanism includes a crank arm 19 and an insulating pull rod 18 . The insulating pull rod can drive the pressure cylinder to move up and down, and the pressure cylinder includes a cylinder block and a piston 17 . A nozzle 15 is connected to the pressure cylinder 16 . The axis of the output shaft of the servo motor is perpendicular to the moving direction of the moving arc contact. In this embodiment, the reason why the servo motor 4 is used as the power source is to consider that the commonly used spring operating mechanism is used, which is limited by the characteristics of the spring mechanism itself, and the adjustment of the fracture opening distance and the opening and closing speed cannot be realized. Conduct a comprehensive study on the influencing factors of arc voltage and current shape. Using the servo motor, the speed and rotation angle of the output shaft of the motor can be adjusted, and the opening and closing speed and the breaking distance can be adjusted through the transmission system. By changing the opening distance and the opening and closing speed to change the arc temperature and shape, more data affecting the arc parameters can be obtained, which is conducive to finding the arc occurrence law and optimizing the structural design of the switch. In other embodiments, a spring operating mechanism commonly used in circuit breakers can also be used as the operating mechanism.

For the safety of the test, the device body is provided with an explosion-proof disc 7 between the static arc contact and the moving arc contact. When the gas pressure in the device body is too large, the explosion-proof disc is preferentially burst to release the pressure in the device body.

In this embodiment, by setting the measuring cylinder, the installation of the corresponding sensor is more convenient and safer. In other embodiments, the corresponding insert for installing the sensor can also be directly provided on the device body, or the measuring device can also be set in a box shape, the measuring device itself has an installation space for placing the corresponding sensor, and the Corresponding sensor outlet terminals are reserved on the measuring device for connection with external data acquisition devices.

In this embodiment, the contact assembly is composed of static arc contacts and moving arc contacts, which simplifies the fracture structure, reduces the number of dynamic and static main contacts, and generates arcs through the breaking of the dynamic and static arc contacts. The quality of the moving component of the moving arc contact is reduced, the friction between the moving and static main contacts is reduced, and the moving speed of the moving arc contact component is increased to a certain extent, thereby increasing the opening and closing speed. In other embodiments, contact assemblies commonly used in circuit breakers can also be used, including moving contacts and stationary contacts.

Further, by increasing the length of the crank arm 19, the pressing cylinder 16 and the piston 17, the maximum opening distance of the contact is increased, that is, the effective moving distance of the moving arc contact assembly is increased, which is beneficial to the opening and closing speed and Spacing adjustment.

Claims (5)

1. a high-voltage direct current breaking experiment device, is characterized in that: comprise device body and the contact assembly that is positioned in the device body, the contact assembly comprises the static arc contact, the moving arc contact that are arranged up and down, and the experiment device also It includes an operating mechanism for driving the static arc contact and the moving arc contact to open and close, the device body has a cavity for the moving arc contact to move, the static arc contact and the moving arc contact The voltage application terminals are respectively connected with the voltage application terminals, and the static arc contacts and the moving arc contacts form a closed loop when closing by applying voltage to the voltage application terminals. The voltage application terminals are arranged on the device body, and there are In order to observe the observation window of the arc generated by the static arc contact and the moving arc contact when opening, the device body is provided with a measuring device for collecting the corresponding data of the arc, and the measuring device includes a measuring cover and a The temperature sensor and the gas pressure sensor are provided with the corresponding temperature sensor outlet end and the gas pressure sensor outlet end on the measurement cover. The device body is in the shape of a cylinder extending in the up-down direction, and the side wall of the device body is convex in the radial direction. A measuring cylinder is provided, the measuring cylinder has an installation space for placing the temperature sensor and the gas pressure sensor in communication with the cavity of the device body, and the measuring cover plate is connected to the measuring cylinder. 2 . The high-voltage direct current breaking experiment device according to claim 1 , wherein the contact assembly is composed of a static arc contact and a moving arc contact. 3 . 3. The high-voltage direct current breaking experiment device according to claim 1 is characterized in that: the operating mechanism is a motor-driven operating mechanism, and the motor-driven operating mechanism comprises a servo motor and is located between the servo motor and the moving arc contact. transmission mechanism between. 4 . The high-voltage direct current breaking experiment device according to claim 3 , wherein the axis of the output shaft of the servo motor is perpendicular to the moving direction of the moving arc contact. 5 . 5 . The high-voltage direct current breaking experiment device according to claim 1 , wherein the device body is provided with an explosion-proof disc between the static arc contact and the moving arc contact. 6 .