New high voltage outdoor vacuum switch

Abstract

The present invention relates to a new type of high-voltage outdoor vacuum switch used in the field of high-voltage switch electrical equipment, and is particularly designed with a short-circuit grounding insulating plug-in head and a phase-to-phase connecting insulating plug-in head (27). The new type of high-voltage outdoor vacuum switch comprises: a detuning voltage transformer (52) for suppressing resonance; a plug-in current transformer (54) specially used for measuring small currents; and an observation window (37) designed for observing the state of the isolating switch. Due to the use of a built-in external plug-in head, the insulation test does not need to open the cover plate, and only the protective cover needs to be opened, making the acceptance test simple and easy. The use of the plug-in current transformer (54) saves the combined current and voltage transformers. With the observation window (37), misoperation can be effectively avoided.

Description

Technical Field

[0001] The invention relates to a novel high-voltage outdoor vacuum switch (3.6 kV-40.5 kV), in particular to an outdoor fully sealed and fully insulated high-voltage vacuum switch. Background Art

[0002] At present, the known high-voltage outdoor vacuum switch features are as follows:

[0003] ① When the voltage transformer (also used for voltage power supply) is built-in, if the zero-sequence voltage signal is to be obtained, the tail end of the three-phase high-voltage coil must be short-circuited and then grounded, which brings the following problems:

[0004] a. When conducting insulation withstand voltage test on site, if there is no frequency doubling power supply, the tail end of the high voltage coil must be ungrounded and sufficient space must be provided to conduct the test;

[0005] b. To remove the grounding wire, the entire sealed box must be opened (if it is not sealed, it cannot be guaranteed that there will be no condensation inside). After the test, it will be sealed again. It is difficult to ensure the same sealing conditions as when it leaves the factory.

[0006] ② When the voltage transformer (also used for voltage power supply) is built-in, if there is no need to obtain the zero-sequence voltage signal, only the three-phase voltage signal is needed, the tail end of the high-voltage coil of the voltage transformer of phase A should be connected with the tail end of the high-voltage coil of phase B (phase B has no voltage transformer) and phase C, and no longer grounded, so that the three-phase voltage signal can be measured on the secondary side. This also brings the following problems:

[0007] a. When conducting the phase-to-phase insulation withstand voltage test on site, the high-voltage coil tail end connection wire must be removed and sufficient space must be ensured to conduct the test;

[0008] b. To remove the connecting wires, the entire sealed box must be opened (if it is not sealed, it cannot be guaranteed that there will be no condensation inside). After the test, it must be sealed again, and it is difficult to ensure the same sealing conditions as when it leaves the factory.

[0009] c. It will take up a lot of space, making the whole machine too large.

[0010] ③When ferromagnetic resonance occurs in the power system, the high-frequency component is induced to the secondary side, which will cause a very high voltage to appear in the zero-sequence voltage sampling circuit and burn the protection equipment. At the same time, the resonance will also produce low-frequency components. Since the primary circuit of the voltage transformer presents low impedance to the low-frequency signal, this will cause excessive current and burn the fuse or voltage transformer. Due to the small size of the high-voltage outdoor vacuum switch and the inconvenience of maintenance, it is very difficult to install a primary detuning device, and the effect of the secondary detuning device is not ideal.

[0011] ④When the load current is less than 200A, the measurement accuracy of the primary through-type current transformer will decrease and cannot meet the needs of metering and charging. The current transformer attached to the high-voltage outdoor vacuum switch can only be through-type once due to space limitations (that is, the number of turns of the primary coil can only be one turn). The current method is: install a combined current and voltage transformer next to the high-voltage outdoor vacuum switch, which is specifically used for metering. Set up a fee control metering box to control the high-voltage outdoor vacuum switch to open after arrears. This results in excessive space occupation, cumbersome installation, and high cost.

[0012] ⑤Since the ability of the vacuum interrupter to isolate static voltage is weak, the isolating switch must be opened after a power outage to successfully test the electricity. If the isolating switch is external, the isolating fracture can be clearly visible and safely operated, but the isolating switch contacts will be seriously oxidized by the environment, increasing the probability of accidents such as contact heating. If the isolating switch is built-in, the problem of rapid oxidation of the isolating switch contacts by the environment can be solved, but the isolating fracture is difficult to be clearly visible and safely operated, and the state of the isolating switch can only be judged by external pointers.

[0013] SUMMARY OF THE INVENTION

[0014] Technical Solution

[0015] The purpose of the present invention is to provide a novel high-voltage outdoor vacuum switch to solve the above-mentioned defects.

[0016] The new type of high-voltage outdoor vacuum switch includes: a left-side insulator (divided into three phases); a right-side insulator (divided into three phases); lead-out wires; an insulating rod cavity; a current transformer; a voltage transformer and a fast fuse; an electronic voltage transformer (also called a voltage sensor), a vacuum arc extinguishing chamber; a switch main shaft; a contact compression spring; a crank arm; an isolating switch cavity; a rotary isolating switch moving contact; an isolating switch insulating shaft; a zero-sequence current transformer; an insulating rod; spring contacts; a plug-in current transformer; a short-circuit grounding plug-in connector; a connecting plug-in connector; a harmonic elimination voltage transformer; an isolating switch observation window, etc.

[0017] The above-mentioned new high-voltage outdoor vacuum switch is characterized in that the high-voltage outdoor vacuum switch also includes: the tail end of the high-voltage coil of the voltage transformer is directly grounded through an insulating plug-in head or grounded through a harmonic elimination voltage transformer, and the phase-to-phase connection also uses a special insulating plug-in head; the harmonic elimination voltage transformer adopts a conical head to connect with the voltage transformer, and the contact interface is sealed with flexible silicone rubber; a plug-in current transformer is connected in series to each phase of the main circuit of the high-voltage outdoor vacuum switch, which is specially used for the measurement and protection of small currents (below 200A). Since the number of turns of the primary coil of the current transformer can be adjusted as needed to ensure sufficient excitation current, it is easy to ensure the measurement accuracy; an observation window (made of explosion-proof glass) is provided on the bottom plate of the high-voltage outdoor vacuum switch, and the state of the isolating switch can be directly observed with the help of light.

[0018] Beneficial Effects

[0019] ①Use short-circuit grounding insulated plugs to perform voltage withstand test without opening the cover of the whole machine;

[0020] ②Use the interphase insulating plug to carry out the interphase withstand voltage test without opening the cover of the whole machine;

[0021] ③ Built-in primary detuning voltage transformer to avoid the harm caused by ferromagnetic resonance;

[0022] ④ The built-in plug-in current transformer solves the problem of low current measurement and insufficient measurement accuracy, and no longer needs to use bulky external voltage and current combined metering transformers. The plug-in structure makes replacement and maintenance extremely convenient;

[0023] ⑤ An observation window is provided on the bottom plate of the high-voltage outdoor vacuum switch, through which the state of the isolating switch can be directly observed with the help of light, thus avoiding the possibility of misoperation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is the main cross-sectional view of the common feeder type of the high-voltage outdoor vacuum switch;

[0025] Figure 2 This is the axial view of the common feeder type of the high voltage outdoor vacuum switch;

[0026] Figure 3 This is the main cross-sectional view of the common ring network type of the high-voltage outdoor vacuum switch;

[0027] Figure 4 This is the axial view of the common ring network type of the high-voltage outdoor vacuum switch;

[0028] Figure 5 This is the main cross-sectional view of the detuning feeder type of the high-voltage outdoor vacuum switch;

[0029] Figure 6 It is a cross-sectional view of the detuning ring network type of the high-voltage outdoor vacuum switch;

[0030] Figure 7 This is the axial view of the detuning ring network type of the high-voltage outdoor vacuum switch;

[0031] Figure 8 This is the main cross-sectional view of the common metering type of the high-voltage outdoor vacuum switch;

[0032] Fig. 9 This is the main cross-sectional view of the high-voltage outdoor vacuum switch of the detuning and metering type;

[0033] Fig.10 This is the axial view of the detuning and metering type of the high-voltage outdoor vacuum switch.

[0034] In the figure: 1-outgoing line terminal; 2-outgoing line conductor; 3-zero sequence current transformer; 4-outgoing line current transformer; 5-left insulator (B phase); 6-outgoing line electronic voltage transformer (also called sensor); 7-lever; 8-insulating pull rod; 9-contact compression spring; 10-crank arm; 11-switch main shaft; 12-insulating pull rod cavity; 13-spring contact finger; 14-silicon rubber insulating gasket; 15-incoming line electronic voltage transformer; 16-upper cover; 17-voltage Fast fuse for transformer; 18-current transformer on the incoming line; 19-voltage transformer on the incoming line (electromagnetic voltage transformer or power-taking capacitor); 20-conductor on the incoming line; 21-incoming and outgoing line end sheds; 22-incoming line terminal; 23-vacuum arc extinguishing chamber; 24-right insulator (B phase); 25-moving conductive rod of the arc extinguishing chamber; 26-plug-in cover; 27-short-circuit grounding insulated plug-in or interphase connection insulated plug-in; 28-grounding contact compression spring; 29-voltage transformer The high-voltage coil tail end leads to the compression spring; 30-lower cover; 31-arc extinguishing chamber moving end leads to the conductor; 32-incoming line side static contact; 33-isolating contact compression disc spring; 34-rotary isolating switch moving contact; 35-moving contact insulation coating; 36-isolating switch insulation shaft; 37-observation window; 38-sealing ring; 39-pressing frame; 40-isolating switch cavity; 41-outgoing line side static contact; 42-shielding net; 43-operating mechanism; 44-manual energy storage handle; 45-switch operating handle ;46-isolating switch operating handle;47-front side panel;48-rear side panel;49-outgoing voltage transformer (three-phase V / V connection);50-upper cover (for ring network type);51-harmonic elimination voltage transformer cover;52-harmonic elimination voltage transformer;53-upper cover (for metering type);54-plug-in current transformer;55-primary coil conductor;56-silicon rubber sleeve;57-connection contact;58-binding spring;59-main circuit conductor;60-three-phase connection plug-in head. Specific embodiments

[0035] The new high-voltage outdoor vacuum switch includes:

[0036] (1) Outgoing line terminal 1 - used to connect to the external primary wire;

[0037] (2) Outgoing conductor 2 - for internal conduction;

[0038] (3) Zero-sequence current transformer 3 - used to measure zero-sequence current;

[0039] (4) Current transformer 4 on the outgoing line side - used to measure current;

[0040] (5) Left insulator (phase B in the figure) 5- plays a supporting and insulating role. Due to the limitation of processing technology, the entire insulator is divided into left insulator and right insulator, and each side insulator is divided into three phases A, B, and C for processing and manufacturing;

[0041] (6) Electronic voltage transformer 6 on the outgoing line side - used for measuring voltage;

[0042] (7) Lever 7 - for transmission;

[0043] (8) Insulating pull rod 8 - for insulating transmission;

[0044] (9) Contact compression spring 9 - to ensure sufficient contact pressure between the moving and static contacts of the vacuum interrupter (23);

[0045] (10) crank arm 10 - for transmission;

[0046] (11) Switch main shaft 11- drives the three-phase vacuum interrupter (23) for rapid action;

[0047] (12) Insulating rod cavity 12 - for internally storing the insulating rod (8);

[0048] (13) Spring contact finger 13 - used for sliding contact between the moving end lead conductor (31) and the moving conductive rod (25) of the arc extinguishing chamber;

[0049] (14) Silicone rubber insulating gasket 14 - plays the role of sealing and insulation;

[0050] (15) Incoming line side electronic voltage transformer 15 - used to measure the incoming line side phase voltage and zero sequence voltage;

[0051] (16) Upper cover plate 16 - for sealing and protection;

[0052] (17) Fast fuse for voltage transformer 17-Protecting voltage transformer (19)

[0053] (18) Current transformer on the incoming line side 18 - used to measure current;

[0054] (19) Incoming line voltage transformer (electromagnetic voltage transformer or power-taking capacitor) 19 - used to measure voltage and provide operating power or float charge for batteries;

[0055] (20) Incoming line conductor 20 - for internal conduction;

[0056] (21) Inlet and outlet end sheds 21 - used to increase creepage distance;

[0057] (22) Incoming line terminal 22 - used to connect to the external primary wire;

[0058] (23) Vacuum interrupter 23 - used for opening and closing normal current and short-circuit current;

[0059] (24) Right insulator 24 - plays a supporting and insulating role. Due to the limitation of processing technology, the whole insulator is divided into left insulator and right insulator, and each side insulator is divided into three phases A, B, and C for easy processing and manufacturing;

[0060] (25) Arc extinguishing chamber moving conductive rod 25 - for external lead wire;

[0061] (26) plug head cover 26-used to protect the plug head (27);

[0062] (27) Short-circuit grounding insulated plug-in connector or interphase connection insulated plug-in connector 27 - For short-circuit grounding or interphase connection of the high-voltage coil tail of the voltage transformer;

[0063] (28) Ground contact compression spring 28-for ground contact;

[0064] (29) The voltage transformer high voltage coil tail end leads to a compression spring 29 - for electrical connection;

[0065] (30) Lower cover plate 30 - for sealing and protection;

[0066] (31) Arc extinguishing chamber moving end lead conductor 31-for the lead wire of vacuum arc extinguishing chamber 23;

[0067] (32) Incoming line side static contact 32 - used to connect the rotary isolating switch moving contact 34;

[0068] (33) Isolating contact pressing disc spring 33 - used to maintain sufficient pressure between the isolating switch moving contact (34) and the stationary contacts (32) and (41);

[0069] (34) Rotary isolating switch moving contact 34 - connected for conducting and isolating functions;

[0070] (35) Moving contact insulation coating 35 - strengthen insulation effect;

[0071] (36) Isolating switch insulating shaft 36 - for transmission and insulation;

[0072] (37) Observation window 37 - used to observe the status of the isolating switch;

[0073] (38) Sealing ring 38 - sealing function;

[0074] (39) Press frame 39 - used to fix the observation window;

[0075] (40) Isolating switch cavity 40 - for placing the isolating switch;

[0076] (41) Outgoing line side static contact 41 - used to connect the rotary disconnector moving contact 34;

[0077] (42) Shielding net 42-Used for uniform voltage and reducing partial discharge;

[0078] (43) Operating mechanism 43 - for switch and isolating switch operation and interlocking;

[0079] (44) Manual energy storage handle 44 - for manual energy storage;

[0080] (45) Switch operating handle 45 - used to operate the switch;

[0081] (46) Isolating switch operating handle 46 - used to operate the isolating switch;

[0082] (47) Front side plate 47 - to prevent ultraviolet rays from irradiating the insulator and provide protection;

[0083] (48) Rear side plate 48 - to prevent ultraviolet rays from irradiating the insulation and protection;

[0084] (49) Voltage transformer on the outgoing line side (three-phase V / V connection) 49- used to measure voltage and provide power when reverse power is transmitted;

[0085] (50) Upper cover (for ring network type) 50-for protection;

[0086] (51) Harmonic elimination voltage transformer cover 51 - for protection and grounding;

[0087] (52) Harmonic elimination voltage transformer 52-used to eliminate grid resonance;

[0088] (53) Upper cover (for metering type) 53-for protection;

[0089] (54) Plug-in current transformer 54 - used for small current measurement;

[0090] (55) Primary coil wire 55 - used to connect the primary coil to the outside;

[0091] (56) Silicone rubber sleeve 56 - for interface sealing and insulation;

[0092] (57) Connecting contact finger 57 - used for active connection between two hard conductors;

[0093] (58) Binding spring 58 - to ensure sufficient pressure on the contact finger;

[0094] (59) Main circuit conductor 59-used for electrical connection between the static end of the arc extinguishing chamber and the plug-in current transformer (54);

[0095] (60) Three-phase connection plug 60-connects the tail end of the high-voltage coil of the A and C phase voltage transformer and the B phase conductor to form a V / V wiring method.

[0096] The following is combined with Figures 1 to 10 The present invention will be further described with reference to the following embodiments:

[0097] 1. Key points of the new high-voltage outdoor vacuum switch structure:

[0098] ① Use a short-circuit grounding insulated plug (27) at the end of the high-voltage coil of the voltage transformer (19). During the on-site acceptance test, there is no need to open the cover of the whole machine. The withstand voltage test can be carried out by unplugging the plug. Note: The voltage transformer is a fully insulated type;

[0099] ② Use the interphase insulating plug (27). During the on-site acceptance test, there is no need to open the lower cover (30) of the whole machine. The interphase withstand voltage test can be carried out by unplugging the plug (27). Note: The B-phase voltage transformer is replaced by an insulating conductor;

[0100] ③ A built-in but external primary harmonic elimination voltage transformer (52) is used to avoid the harm caused by electromagnetic resonance, and replacement and maintenance are extremely convenient;

[0101] ④ The built-in plug-in current transformer (54) solves the problem of insufficient precision in measuring small currents. Instead of using a bulky external voltage and current combined measuring transformer alone, only one switch is used to realize functions such as line protection, equipment protection, power supply upon payment, and power outage upon arrears. It has the characteristics of small size, easy installation and use, and reduces the cost.

[0102] ⑤ An observation window (37) is provided on the bottom plate of the high-voltage outdoor vacuum switch, and the state of the isolating switch (34) can be directly observed with the help of light, thereby avoiding the possibility of misoperation.

[0103] 2. Vacuum switch closing and opening process:

[0104] Figure 1 The figure shows the state of the switch after closing. Driven by the operating mechanism (43), the switch main shaft (11) rotates rapidly clockwise, driving the crank arm (10) to rotate clockwise, and then driving the lever (7) to rotate clockwise, and finally driving the insulating pull rod (8) to move leftward to separate the moving and static contacts of the vacuum interrupter (23) and to maintain a certain distance, thus completing the opening. On the contrary, driven by the operating mechanism (43), the switch main shaft (11) rotates rapidly counterclockwise, driving the crank arm (10) to rotate counterclockwise, and finally the lever (7) drives the insulating pull rod (8) to move rightward until the moving and static contacts in the interrupter are in contact and maintain a certain pressure under the action of the contact compression spring (9) (see attached). Figure 1 ) to complete the closing.

[0105] 3. Closing and opening process of the isolating switch

[0106] Attached Figure 1 The figure shows the state of the disconnector after closing. Figure 8The figure shows the state of the isolating switch after opening. When opening, the isolating switch insulating shaft (36) rotates 90° clockwise, driving the two ends of the rotary isolating switch moving contact (34) to separate from the isolating switch static contacts (32) and (41) at the same time, forming an isolating break between the two static contacts (32) and (41). When closing, it rotates 90° counterclockwise again, driving the two ends of the rotary isolating switch moving contact (34) to connect with the isolating switch static contacts (32) and (41) at the same time, so that a loop is formed on both sides of the incoming and outgoing lines, and the closing is completed.

Claims

1. New high-voltage outdoor vacuum switch, characterized in that: The invention comprises three independent voltage transformers (19) and a plug-in current transformer (54) connected in series in the conductive main circuit. The voltage transformer is a fully insulated type. The three voltage transformers (19) constitute a built-in three-phase voltage transformer. The high-voltage coil tail end of the three-phase voltage transformer is short-circuited through a short-circuit grounding insulating plug-in head (27). After the short-circuit, the short-circuit grounding insulating plug-in head (27) is directly grounded, or the high-voltage coil tail end of the three-phase voltage transformer is connected to a built-in external resonance suppression harmonic elimination voltage transformer (52) and then grounded through the harmonic elimination voltage transformer (52). The harmonic elimination voltage transformer (52) is connected to the voltage transformer using a conical head. The high-voltage coil tail ends of two of the voltage transformers in the built-in three-phase voltage transformer are connected phase to phase through a phase-to-phase connection insulating plug-in head (60). A hole is opened on the bottom plate of the novel high-voltage outdoor vacuum switch and an isolating switch observation window (37) is installed.

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