Test model of mechanical hybrid on-load tap-changer and method thereof

Abstract

The invention provides a mechanical hybrid on-load tap-changer test model and a method thereof.The test model comprises a single-phase motor, a gun release mechanism, an anti-parallel thyristor module, a telescopic contact assembly and an electrode assembly, the gun release mechanism is powered by the single-phase motor to drive the gun release mechanism to reciprocate left and right in the direction of a telescopic contact, and the anti-parallel thyristor module is connected with the telescopic contact assembly. The telescopic contact assembly is arranged on an upper sliding plate of the gun release mechanism and connected with the upper sliding plate through a bolt, so that the telescopic contact assembly and the electrode assembly are disconnected and connected, disconnection and connection of a fracture of the change-over switch are simulated, and the thyristor module assembly is connected to the two ends of the fracture of the telescopic contact assembly and the two ends of the fracture of the electrode assembly in parallel. According to the invention, less equipment is needed, the structure is simple, functions can be added according to requirements, and the method has stronger applicability and expansibility.

Description

Technical Field

[0001] The present invention relates to the technical field of on-load tap changers, and more particularly to a test model of a mechanical hybrid on-load tap changer. Background Art

[0002] In recent years, with the development of power electronics in power equipment, mechanical hybrid transformer on-load tap-changers with thyristor-assisted arc extinguishing have been commercially applied. On the basis of ordinary oil-immersed on-load tap-changers, thyristor modules are added to avoid contact ablation and transformer oil pollution during switching. When optimizing the design of hybrid on-load tap-changers, it is not economical to directly adjust the fracture arrangement of the switch on the prototype. Therefore, it is very necessary to design a test model that can be easily adjusted to test the action characteristics and electrical characteristics. Summary of the invention

[0003] In order to solve the technical problem in the background art that there is a lack of such a conveniently adjustable test model for testing action characteristics and electrical characteristics, the present invention provides a test model of a mechanical hybrid on-load tap changer, the test model comprising:

[0004] In order to solve the above problems, the present invention provides a test model of a mechanical hybrid on-load tap changer. Its structure has the same triggering action mode and elastic modulus as the gun in the hybrid on-load tap changer prototype, can simulate the breaking process of a group of breaks of the hybrid on-load tap changer, is simple to operate, and is economical and practical.

[0005] To achieve the above object, the specific scheme of the present invention is as follows: a test model of a mechanical hybrid on-load tap changer, characterized in that the test model comprises: a single-phase motor, a gun release mechanism, an anti-parallel thyristor module, a telescopic contact assembly and an electrode assembly, wherein:

[0006] The gunshot release mechanism is powered by a single-phase motor and drives the gunshot release mechanism to reciprocate left and right along the direction of the telescopic contact, thereby driving the opening and closing of the telescopic contact assembly and the electrode assembly, thereby simulating the opening and closing of the tap switch break;

[0007] The telescopic contact assembly is placed on the upper slide plate of the gunshot release mechanism and connected by bolts to realize the opening and closing of the telescopic contact assembly and the electrode assembly, thereby simulating the opening and closing of the break of the switch;

[0008] The thyristor module assembly is connected in parallel at both ends of the break of the telescopic contact and the electrode assembly.

[0009] In the above-mentioned test model of a mechanical hybrid on-load tap changer, the bolt release mechanism includes: an upper slide plate, an energy storage spring, a compression block, a buffer spring, a guide rail, a guide rail, a lower slide plate, a right roller, a support plate, a rocker arm, a right grab, a bottom plate, a left return spring, a left pressure wheel, a left claw, a right return spring, a left roller and a right pressure wheel. The assembly relationship of each component is as follows: the energy storage spring and the compression block are sleeved on the guide rail and installed as a whole on the upper slide plate, and buffer springs are installed at both ends respectively; the right roller is installed on the lower slide plate and assembled with the guide rail; the left pressure wheel and the left return spring are installed on the grab and installed as a whole on the bottom plate, and the support plate and the rocker arm are fixed to the bottom plate with bolts; during the overall assembly, the compression block is ensured to be stuck inside the lower slide plate.

[0010] In the above-mentioned test model of a mechanical hybrid on-load tap changer, when the telescopic contact is disconnected, the movement process of the shooting release mechanism is: when the rocker arm swings to the left, it drives the lower slide to push the compression block and the upper slide to compress the energy storage spring together. When the left roller on the lower slide moves to a certain extent, it will press on the left claw card on the left side to compress the left return spring. At this time, the left pressure wheel leaves the slot of the upper slide, and the upper slide and the compression block move to the left side driven by the energy storage spring. The energy storage spring is released, and then the grab card and the right pressure wheel are stuck in the slot of the upper slide under the action of the right return spring.

[0011] In the above-mentioned test model of a mechanical hybrid on-load tap changer, the anti-parallel thyristor module includes: bolts, an upper pressure plate, a thyristor, a conductive lead-out bracket, a lower pressure plate, an insulating pad, nuts, a conductive voltage plate, an insulating bracket, a resistor, a high-voltage silicon stack and a nylon bolt. The assembly relationship of each component is: the resistor and the high-voltage silicon stack are installed on the insulating bracket, the thyristor, the conductive voltage plate and the thyristor are installed on the conductive lead-out bracket, and the entire assembly is installed between the lower pressure plate and the upper pressure plate, and is fastened to the insulating pad using bolts, nuts and nylon bolts.

[0012] In the above-mentioned test model of a mechanical hybrid on-load tap changer, the telescopic contact assembly includes: a copper braided wire 1, a nut 1, an insulating bracket, a conductive bolt, a spring 1, a copper contact, a trigger copper contact, a spring 2, a trigger conductive bolt, a copper braided wire 2, a nut 2, an electrode block, a screw, a nut 3, a positioning piece, a bolt, a nut 4 and an insulating plate, and the assembly relationship of the components is: the spring 1 and the copper contact are mounted on the insulating bracket, the copper braided wire 1 is mounted on the conductive bolt and fastened to the insulating bracket with a nut 1, the spring 2 and the trigger copper contact are mounted on the insulating bracket, the copper braided wire 2 is mounted on the trigger conductive bolt and fastened with a nut 2, and the whole is mounted on the electrode block and fastened with a positioning piece, a bolt and a nut 4; the whole is fixed to the insulating plate with a nut 3 and a screw; the electrode block is arranged between the copper contact and the trigger copper contact, and is symmetrically distributed at the fracture.

[0013] In the above-mentioned test model of a mechanical hybrid on-load tap changer, the electrode assembly includes: an electrode, an insulating plate, a spring, a stud, an insulating plate, a flat washer and a nut five, and the assembly relationship of the components is: the stud is fixed on the electrode, the insulating plate and the spring are installed on the stud, and the whole is installed on the insulating plate, and is fastened using a flat washer and a nut five.

[0014] In the above-mentioned test model of a mechanical hybrid on-load tap changer, the test model utilizes the left and right movement of the gunshot release mechanism in combination with the contact relationship between the telescopic contact assembly and the electrode assembly to realize the simulated function.

[0015] In the above-mentioned test model of a mechanical hybrid on-load tap changer, a single-phase motor is connected to a gun-shooting release mechanism through a connecting rod, the telescopic contact assembly and the upper mounting plate of the gun-shooting release mechanism are connected together by bolts, the thyristor module is connected in parallel with the break, and the single-phase motor provides power to move the gun-shooting release mechanism left and right, thereby driving the opening and closing of the telescopic contact assembly and the electrode assembly, thereby realizing the opening and closing of the simulated tap changer break.

[0016] The present invention also provides a method for conducting a simulation test on the test model of the mechanical hybrid on-load tap changer according to claim 1, comprising testing the turn-off performance of the thyristor module assembly during the transition process, wherein the turn-off process of the thyristor module assembly is as follows:

[0017]

[0018] Comprehensive

[0019]

[0020] Further deformation:

[0021]

[0022] in, i off (t) is a known quantity,

[0023] make: Then we can get

[0024]

[0025] The voltage to be solved is U = u c +Ri RC ,in,

[0026] The solution of this second-order equation consists of a steady-state response and a transient response, where the transient response and the steady-state response together constitute the voltage overshoot formed when the thyristor is turned off by the natural zero-crossing of the current.

[0027] Where L is the load inductance, i a is the current flowing through the thyristor module, R L is the load resistance value, R is the distributed parameter resistance value of the thyristor module, C is the distributed parameter capacitance value of the thyristor module, u c is the voltage across the distributed parameter capacitor, U m is the tap changer level voltage, i off is the current flowing through the thyristor module when it is turned off, i r is the reverse recovery current, I m is the reverse recovery current peak, τ is the time constant, A and B are equivalent coefficients, i RC is the current flowing through the distributed parameter resistance and capacitance of the thyristor module.

[0028] In the method for conducting simulation test on the test model of the mechanical hybrid on-load tap changer, the test model utilizes the left and right movement of the gunshot release mechanism in combination with the contact relationship between the telescopic contact assembly and the electrode assembly to realize the simulation function.

[0029] Compared with the closest prior art, the beneficial effects of the present invention are as follows:

[0030] (1) The test model provided by the present invention has the same triggering action mode and elastic modulus as the bolt in the hybrid on-load tap changer, and can completely and equivalently simulate the breaking process of a group of fractures of the prototype;

[0031] (2) The test model can flexibly adjust the bolt counterweight, spring, size and shape of the contacts, as well as the action sequence of each contact, to facilitate testing and optimize the design of the prototype.

[0032] (3) The gun-shot release mechanism used in the test model and the gun-shot release mechanism in the hybrid on-load tap-changer are both mature structures and mechanisms used in mainstream products on the market at this stage. They have the same mechanism principles and high reliability in action switching and are more stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] A more complete understanding of exemplary embodiments of the present invention may be obtained by referring to the following drawings:

[0034] Figure 1 is a structural diagram of a mechanical hybrid on-load tap changer test model according to a specific embodiment of the present invention;

[0035] Figure 2 is a structural diagram of a bolt release mechanism according to a specific embodiment of the present invention;

[0036] Figure 3 is a structural diagram of an anti-parallel thyristor module according to a specific embodiment of the present invention;

[0037] Figure 4 is a structural diagram of a telescopic contact assembly according to a specific embodiment of the present invention;

[0038] Figure 5 It is a structural diagram of an electrode assembly according to a specific embodiment of the present invention. DETAILED DESCRIPTION

[0039] The present invention will be further described below in conjunction with the accompanying drawings.

[0040] Figure 1 It is a structural diagram of a mechanical hybrid on-load tap changer test model according to a specific embodiment of the present invention.

[0041] like Figure 1 As shown, the test model of the mechanical hybrid on-load tap changer of the present invention comprises:

[0042] Single-phase motor, gunshot release mechanism, anti-parallel thyristor module, telescopic contact assembly and electrode assembly. The gunshot release mechanism is powered by the single-phase motor, driving the gunshot release mechanism to reciprocate left and right along the direction of the telescopic contact. The telescopic contact assembly is placed on the upper slide of the gunshot release mechanism and connected by bolts. In this way, the telescopic contact assembly and the electrode assembly can be opened and closed, thereby simulating the opening and closing of the switch. The thyristor module assembly is connected in parallel to the telescopic contact and the electrode assembly.

[0043] The test model uses the characteristics of the left and right movement of the gun release mechanism, combined with the contact relationship between the telescopic contact assembly and the electrode assembly, to achieve the simulated function. The connection relationship is that the single-phase motor is connected to the gun release mechanism through a connecting rod, the telescopic contact assembly and the upper mounting plate of the gun release mechanism are connected together by bolts, the thyristor module is connected in parallel with the break, and the single-phase motor provides power to make the gun release mechanism move left and right, thereby driving the opening and closing of the telescopic contact assembly and the electrode assembly. This simulates the opening and closing of the tap switch break.

[0044] When a simulation test is carried out using the mechanical hybrid on-load tap changer test model according to the specific embodiment of the present invention to test the turn-off performance of the thyristor module during the transition process, the turn-off process of the thyristor module is described as follows:

[0045]

[0046] Comprehensive

[0047]

[0048] Further deformation:

[0049]

[0050] in, ioff (t) is a known quantity.

[0051] For the convenience of analysis, Then we can get

[0052]

[0053] The voltage to be solved is U = u c +Ri RC ,in,

[0054] The solution of the second-order equation consists of a steady-state response and a transient response, wherein the transient response and the steady-state response together constitute the voltage overshoot formed when the thyristor is turned off by naturally crossing the zero current.

[0055] Where L is the load inductance, i a is the current flowing through the thyristor module, R L is the load resistance value, R is the distributed parameter resistance value of the thyristor module, C is the distributed parameter capacitance value of the thyristor module, u c is the voltage across the distributed parameter capacitor, U m is the tap changer level voltage, i off is the current flowing through the thyristor module when it is turned off, i r is the reverse recovery current, I m is the reverse recovery current peak, τ is the time constant, A and B are equivalent coefficients, i RC is the current flowing through the distributed parameter resistance and capacitance of the thyristor module.

[0056] Figure 2 1 is a structural diagram of the bolt release mechanism in a specific embodiment of the present invention. Figure 2 As shown, the assembly relationship of each component is:

[0057] The energy storage spring 22 and the compression block sleeve 23 are on the guide rail 25 and are installed as a whole on the upper slide 21, and buffer springs 24 are installed at both ends respectively; the right roller 28 is installed on the lower slide 27 and assembled with the guide rail 26; the left pressure wheel 214 and the left return spring 213 are installed on the grabber 211, and the whole is installed on the bottom plate 212, and the support plate 29 and the rocker arm 210 are fixed to the bottom plate 212 with bolts; during the overall assembly, ensure that the compression block 23 is stuck inside the lower slide 27.

[0058] When the telescopic contacts are disconnected, the movement process of the shooting release mechanism is as follows: when the rocker arm 210 swings to the left, it drives the lower slide 27 to push the compression block 23 and the upper slide 21 to compress the energy storage spring 22. When the roller 217 on the lower slide 27 moves to a certain extent, it will press on the grab card 215 on the left, compressing the left return spring 213. At this time, the roller 214 leaves the slot of the upper slide 21, and the upper slide 21 and the compression block 23 move to the left side driven by the energy storage spring 22. The energy storage spring 22 is released, and then the grab card 211 and the roller 218 are stuck in the slot of the upper slide 21 under the action of the right return spring 216.

[0059] Figure 3 is a structural diagram of an anti-parallel thyristor module in a specific embodiment of the present invention. Figure 3 As shown, the assembly relationship of each component is:

[0060] The resistor 310 and the high-voltage silicon stack 311 are installed on the insulating bracket 39, the lower pressure plate 34 is installed on the lower pressure plate 35, the thyristor 33, the conductive plate 38, and the thyristor 33 are installed between the lower pressure plate 35 and the upper pressure plate 32, and are fastened to the insulating pad 36 using bolts 31, nuts 37, and nylon bolts 312.

[0061] Figure 4 is a structural diagram of a telescopic contact assembly in a specific embodiment of the present invention. Figure 4 As shown, the assembly relationship of each component is:

[0062] Spring 1 45 and copper contact 46 are mounted on insulating bracket 43, copper braided wire 1 41 is mounted on conductive bolt 44 and fastened to insulating bracket 43 with nut 1 42, spring 2 48 and trigger copper contact 47 are mounted on insulating bracket 43, copper braided wire 2 410 is mounted on trigger conductive bolt 49 and fastened with nut 2 411, and the whole is mounted on electrode block 412 and fastened with positioning piece 415, bolt 416 and nut 4 417; the whole is fixed to insulating plate 418 with nut 3 414 and screw 413. Electrode block 412 is arranged between copper contact 46 and trigger copper contact 47, and symmetrically distributed at the fracture.

[0063] Figure 5 is a structural diagram of an electrode assembly in a specific embodiment of the present invention. Figure 5 As shown, the assembly relationship of each component is:

[0064] The stud 54 is fixed on the electrode 51 , the insulating plate 52 and the spring 53 are mounted on the stud 54 , and the whole is mounted on the insulating plate 55 , and is fastened using a flat washer 56 and a nut 57 .

[0065] The present invention is described in detail above in conjunction with the embodiments of the accompanying drawings. A person skilled in the art can make various variations of the present invention according to the above description. Therefore, certain details in the embodiments should not constitute a limitation of the present invention, and the scope of protection of the present invention shall be defined by the scope of the attached claims.

Claims

1. A test model of a mechanical hybrid on-load tap changer, characterized in that: The test model includes: a single-phase motor, a gunshot release mechanism, an anti-parallel thyristor module, a telescopic contact assembly and an electrode assembly, wherein: The gunshot release mechanism is powered by a single-phase motor and drives the gunshot release mechanism to reciprocate left and right along the direction of the telescopic contact, thereby driving the opening and closing of the telescopic contact assembly and the electrode assembly, thereby simulating the opening and closing of the tap switch break; The telescopic contact assembly is placed on the upper slide plate of the gunshot release mechanism and connected by bolts to realize the opening and closing of the telescopic contact assembly and the electrode assembly, thereby simulating the opening and closing of the break of the switch; The thyristor module assembly is connected in parallel at both ends of the break of the telescopic contact and the electrode assembly.

2. A test model of a mechanical hybrid on-load tap changer according to claim 1, characterized in that: The bolt release mechanism comprises: an upper slide plate (21), an energy storage spring (22), a compression block (23), a buffer spring (24), a guide rail (25), a guide rail (26), a lower slide plate (27), a right roller (28), a support plate (29), a rocker arm (210), a right gripper (211), a bottom plate (212), a left return spring (213), a left pressure wheel (214), a left claw (215), a right return spring (216), a left roller (217) and a right pressure wheel (218). The assembly relationship of each component is as follows: the energy storage spring (22) and the compression block (23) are sleeved on the guide rail (25), and the whole is installed on the upper slide plate (21), and the buffer springs (24) are installed at both ends respectively; the right roller (28) is installed on the lower slide plate (27) and assembled with the guide rail (26); the left pressure wheel (214) and the left return spring (213) are installed on the grab card (211), and the whole is installed on the bottom plate (212), and the support plate (29) and the rocker arm (210) are fixed on the bottom plate (212) with bolts; during the overall assembly, it is ensured that the compression block card (23) is inside the lower slide plate (27).

3. A test model of a mechanical hybrid on-load tap changer according to claim 2, characterized in that: When the telescopic contact is disconnected, the movement process of the shooting release mechanism is as follows: when the rocker arm (210) swings to the left, it drives the lower slide plate (27) to push the compression block (23) and the upper slide plate (21) to compress the energy storage spring (22). When the left roller (217) on the lower slide plate (27) moves to a certain extent, it will press on the left claw card (215) to compress the left return spring (213). At this time, the left pressure wheel (214) leaves the card slot of the upper slide plate (21), and the upper slide plate (21) and the compression block (23) move to the left side under the drive of the energy storage spring (22). The energy storage spring (22) is released, and then the grab card (211) and the right pressure wheel (218) are stuck in the card slot of the upper slide plate (21) under the action of the right return spring (216).

4. A test model of a mechanical hybrid on-load tap changer according to claim 1, characterized in that: The anti-parallel thyristor module comprises: a bolt (31), an upper pressure plate (32), a thyristor (33), a conductive lead-out bracket (34), a lower pressure plate (35), an insulating pad (36), a nut (37), a conductive voltage plate (38), an insulating bracket (39), a resistor (310), a high-voltage silicon stack (311) and a nylon bolt (312). The assembly relationship of each component is as follows: the resistor (310) and the high-voltage silicon stack (311) are installed on the insulating bracket (39), the thyristor (33), the conductive voltage plate (38), and the thyristor (313) are installed on the conductive lead-out bracket (34), and the entire assembly is installed between the lower pressing plate (35) and the upper pressing plate (32), and is fastened to the insulating pad (36) using bolts (31), nuts (37), and nylon bolts (312).

5. A test model of a mechanical hybrid on-load tap changer according to claim 1, characterized in that: The telescopic contact assembly comprises: a copper braided wire (41), a nut (42), an insulating bracket (43), a conductive bolt (44), a spring (45), a copper contact (46), a trigger copper contact (47), a spring (48), a trigger conductive bolt (49), a copper braided wire (410), a nut (411), an electrode block (412), a screw (413), a nut (414), a positioning member (415), a bolt (416), a nut (417) and an insulating plate (418). The assembly relationship of the components is as follows: the spring 1 (45) and the copper contact (46) are mounted on the insulating bracket (43), the copper braided wire 1 (41) is mounted on the conductive bolt (44) and fastened to the insulating bracket (43) with the nut 1 (42), the spring 2 (48) and the trigger copper contact (47) are mounted on the insulating bracket (43), the copper braided wire 2 (410) is mounted on the trigger conductive bolt (49) and fastened with the nut 2 (411), and the whole is mounted on the electrode block (412) and fastened with the positioning piece (415), the bolt (416) and the nut 4 (417); the whole is fixed to the insulating plate (418) with the nut 3 (414) and the screw (413); the electrode block (412) is arranged between the copper contact (46) and the trigger copper contact (47) and is symmetrically distributed at the fracture.

6. A test model of a mechanical hybrid on-load tap changer according to claim 1, characterized in that: The electrode assembly comprises: an electrode (51), an insulating plate (52), a spring (53), a stud (54), an insulating plate (55), a flat washer (56) and a nut (57). The assembly relationship of each component is as follows: the stud (54) is fixed on the electrode (51), the insulating plate (52) and the spring (53) are installed on the stud (54), and the whole is installed on the insulating plate (55), and is fastened using a flat washer (56) and a nut (57).

7. A test model of a mechanical hybrid on-load tap changer according to claim 1, characterized in that: The test model realizes the simulation function by utilizing the left-right movement of the gunshot release mechanism and combining the contact relationship between the telescopic contact assembly and the electrode assembly.

8. A test model of a mechanical hybrid on-load tap changer according to claim 7, characterized in that: The single-phase motor is connected to the shooting release mechanism through a connecting rod, the telescopic contact assembly and the upper mounting plate of the shooting release mechanism are connected together by bolts, the thyristor module is connected in parallel with the break, and the single-phase motor provides power to make the shooting release mechanism move left and right, thereby driving the telescopic contact assembly and the electrode assembly to open and close, thereby realizing the opening and closing of the simulated tap changer break.

9. A method for conducting a simulation test on the test model of the mechanical hybrid on-load tap changer as claimed in claim 1, comprising testing the turn-off performance of the thyristor module assembly during the transition process, wherein the turn-off process of the thyristor module assembly is as follows: Comprehensive Further deformation: in, i off (t) is a known quantity, make: Then we can get The voltage to be solved is U = u c +Ri RC ,in, The solution of this second-order equation consists of a steady-state response and a transient response, where the transient response and the steady-state response together constitute the voltage overshoot formed when the thyristor is turned off by the natural zero-crossing of the current. Where L is the load inductance, i a is the current flowing through the thyristor module, R L is the load resistance value, R is the distributed parameter resistance value of the thyristor module, C is the distributed parameter capacitance value of the thyristor module, u c is the voltage across the distributed parameter capacitor, U m is the tap changer level voltage, i off is the current flowing when the thyristor module is turned off, i r is the reverse recovery current, I m is the reverse recovery current peak, τ is the time constant, A and B are equivalent coefficients, i RC is the current flowing through the distributed parameter resistance and capacitance of the thyristor module.

10. A method for conducting a simulation test on a test model of a mechanical hybrid on-load tap changer according to claim 9, wherein the test model utilizes the left and right movement of a gunshot release mechanism in combination with the contact relationship between a telescopic contact assembly and an electrode assembly to realize a simulation function.

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