Auxiliary exciter with an integral independent structure to resist different axial expansion of the stator and rotor of the generator

Abstract

The invention discloses an integral independent structure auxiliary exciter that resists different axial expansion of the stator and rotor of a generator, and solves the problem that the stator and rotor of the auxiliary exciter installed on the shaft end of the non-driving end of the generator are easily affected by the different axial expansion of the stator and rotor of the generator, resulting in positioning and matching deviation. An elastic column pin plug-in countersunk hole (14) is arranged on the outer surface of the shaft end of the non-driving end shaft extension (1) of the generator, an auxiliary exciter stator base (5) is fixedly connected to the non-driving end bearing outer cover (4) of the generator, an auxiliary exciter rotor front end shaft extension (11) is arranged at the front end of the auxiliary exciter rotor (10), a coupling (12) is arranged on the front end shaft extension (11) of the auxiliary exciter rotor, and an elastic column pin (13) is arranged on the front side of the coupling (12), and the elastic column pin (13) is movably plugged into the elastic column pin plug-in countersunk hole (14). The disassembly of the exciter is facilitated, and the stability of the output power of the auxiliary exciter is ensured.

Description

Technical Field

[0001] The invention relates to an auxiliary exciter of a generator, and in particular to an auxiliary exciter of an integral independent structure capable of eliminating the influence of different axial expansion amounts of the stator and rotor of the generator on the stator and rotor assembly structure of the auxiliary exciter. Background Art

[0002] The generator of a thermal power plant is driven by a steam turbine, and the pole rotor of the generator is powered by an exciter. In order to provide a stable excitation power supply for the pole rotor of the generator, an automatic voltage regulator (AVR) is generally configured, and the power supply required by the AVR is provided by the auxiliary exciter, the auxiliary exciter supplies power to the AVR, and the AVR supplies power to the exciter, thereby realizing the strong excitation function; the existing auxiliary exciter rotor and auxiliary exciter stator are separately arranged, the auxiliary exciter stator is assembled on the non-drive end bearing cover of the generator, and the auxiliary exciter rotor is separately connected to the non-drive end shaft end of the generator; during the operation of the generator, since the bearings of the generator need to be maintained regularly, the maintenance is carried out when the non-drive end bearing cover of the generator is removed. Therefore, it is necessary to remove the auxiliary exciter rotor on the shaft end and the auxiliary exciter stator installed on the non-drive end bearing cover of the generator respectively. Only after the auxiliary exciter is disassembled, can the non-drive end bearing cover of the generator be further disassembled, and then the generator bearing can be maintained; in the above-mentioned process of disassembling the auxiliary exciter rotor and the auxiliary exciter stator separately, it is easy to damage the components of the auxiliary exciter; and because the assembly of the auxiliary exciter is achieved through the stopper of the transition fit, there is still a problem of insufficient assembly accuracy when the auxiliary exciter stator and rotor are reassembled separately after disassembly, and repeated adjustments are often required to complete the assembly; in addition, since the split auxiliary exciter stator and rotor are respectively installed on the non-drive end bearing cover of the generator and the shaft end of the generator, during the operation of the generator, due to the different temperature rises of the stator and rotor of the generator, the axial expansion of the stator and rotor is also different, resulting in deviations in the axial matching positioning of the stator and rotor of the auxiliary exciter, which directly leads to unstable output power of the auxiliary exciter and affects the input stability of the AVR. Summary of the invention

[0003] The present invention provides an auxiliary exciter with an integral independent structure capable of resisting different axial expansion of the stator and rotor of a generator, thereby solving the technical problem that the stator and rotor of the auxiliary exciter installed on the shaft end of the non-driving end of the generator are easily affected by the different axial expansion of the stator and rotor of the generator, resulting in positioning and matching deviation.

[0004] The present invention solves the above technical problems through the following technical solutions:

[0005] The overall concept of the present invention is: the stator and rotor of the auxiliary exciter are manufactured into an independent integral assembly structure; an elastic pin countersunk hole is provided on the side of the shaft end of the non-driving end of the generator, a coupling is provided on the front axle extension of the auxiliary exciter, an elastic pin is provided on the front side of the coupling, the auxiliary exciter is installed and connected to the outer cover of the non-driving end bearing of the generator through the front end cover, and the elastic pin provided on the front side of the coupling is movably inserted into the elastic pin countersunk hole provided on the side of the shaft end of the non-driving end of the generator, the generator shaft drives the rotor of the auxiliary exciter to rotate through the elastic pin and the coupling, and the axial expansion of the generator rotor is absorbed by the active cooperation between the elastic pin and the elastic pin countersunk hole. The invention can overcome the influence of different axial expansion of the stator and rotor of the generator on the stator and rotor of the auxiliary exciter, and ensure the positioning accuracy of the stator and rotor of the auxiliary exciter. When maintaining the non-drive end bearing of the generator, it is only necessary to disassemble the connection between the front end bearing cover of the auxiliary exciter and the outer cover of the non-drive end bearing of the generator, and then move the auxiliary exciter outward as a whole, so that the elastic column pin on the coupling fixedly connected to the front shaft extension end of the auxiliary exciter can be disengaged from the elastic column pin countersunk hole on the shaft end face of the non-drive end of the generator, and the auxiliary exciter can be removed as a whole. The present invention realizes the overall independent setting of the auxiliary exciter, and the overall independent installation and disassembly, which ensures the stability of the output power of the auxiliary exciter and the convenience of installation and disassembly.

[0006] An integral independent structure auxiliary exciter for resisting different axial expansion of the stator and rotor of a generator, comprising a non-drive end motor cover of the generator, a non-drive end bearing of the generator is arranged in the non-drive end motor cover of the generator, a non-drive end shaft extension of the generator is arranged in the non-drive end bearing of the generator, a non-drive end bearing outer cover of the generator is arranged on the non-drive end bearing of the generator outside the non-drive end shaft extension of the generator, an elastic column pin plug-in countersunk hole is arranged on the outer side surface of the shaft end of the non-drive end shaft extension of the generator, a stator base of the auxiliary exciter is fixedly connected to the non-drive end bearing outer cover of the generator, and a stator base of the auxiliary exciter is fixedly connected to the stator base of the auxiliary exciter. A front end cover and a rear end cover of an auxiliary exciter are respectively arranged on the seat, a front end cover bearing is arranged on the front end cover of the auxiliary exciter, a rear end cover bearing is arranged on the rear end cover of the auxiliary exciter, an auxiliary exciter rotor is arranged between the front end cover bearing and the rear end cover bearing, a front end shaft extension of the auxiliary exciter rotor is arranged at the front end of the auxiliary exciter rotor, a coupling is arranged on the front end shaft extension of the auxiliary exciter rotor, an elastic pin is arranged on the front side surface of the coupling, the elastic pin is movably inserted in the elastic pin insertion countersunk hole, and a gap is arranged between the front side surface of the coupling and the outer side surface of the shaft end of the shaft extension of the non-driving end of the generator.

[0007] The stator frame of the auxiliary exciter is connected to the outer cover of the non-drive end bearing of the generator through the connecting bolts arranged on the front cover of the auxiliary exciter; eight elastic pin insertion countersunk holes are arranged at equal intervals on the outer side surface of the shaft end of the non-drive end shaft extension of the generator, and eight elastic pins are arranged at equal intervals on the front side surface of the coupling.

[0008] The auxiliary exciter of the independent structure of the present invention realizes a separate and independent overall setting, which completely overcomes the defect of low assembly precision of the stator and rotor during reassembly caused by the traditional auxiliary exciter stator and rotor assembly method, and realizes the overall disassembly and assembly of the auxiliary exciter when maintaining the non-driving end rotor of the generator, which is convenient for disassembly and assembly; in particular, the auxiliary exciter rotor and the generator rotor are movablely matched through the elastic column pin and the elastic column pin plug-in hole, which reserves a gap for absorbing the axial expansion of the generator rotor, solves the problem of different effects on the stator and rotor of the traditional exciter caused by the different expansion amounts of the stator and rotor of the generator in the axial direction during operation, and ensures the stability of the output power of the auxiliary exciter. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic diagram of the structure of the present invention;

[0010] Figure 2 It is a structural schematic diagram of an exciter of an integral independent structure of the present invention;

[0011] Figure 3 Schematic diagram of the structure of the coupling 12 of the present invention. DETAILED DESCRIPTION

[0012] The present invention is described in detail below in conjunction with the accompanying drawings:

[0013] A self-contained auxiliary exciter for resisting different axial expansion of a generator stator and rotor, comprising a generator non-drive end motor end cover 3, a generator non-drive end bearing 2 is arranged in the generator non-drive end motor end cover 3, a generator non-drive end shaft extension 1 is arranged in the generator non-drive end bearing 2, a generator non-drive end bearing outer cover 4 is arranged on the generator non-drive end bearing 2 outside the generator non-drive end shaft extension 1, an elastic column pin plug-in countersunk hole 14 is arranged on the outer side surface of the shaft end of the generator non-drive end shaft extension 1, an auxiliary exciter stator base 5 is fixedly connected to the generator non-drive end bearing outer cover 4, and auxiliary exciter stator base 5 is respectively arranged on the auxiliary exciter stator base 5. The front end cover 6 of the exciter and the rear end cover 7 of the auxiliary exciter, the front end cover bearing 8 is arranged on the front end cover 6 of the auxiliary exciter, the rear end cover bearing 9 is arranged on the rear end cover 7 of the auxiliary exciter, the auxiliary exciter rotor 10 is arranged between the front end cover bearing 8 and the rear end cover bearing 9, the auxiliary exciter rotor 10 is arranged at the front end of the auxiliary exciter rotor 10, the auxiliary exciter rotor front end shaft extension 11 is arranged on the front end shaft extension 11 of the auxiliary exciter rotor, the front side surface of the coupling 12 is arranged with an elastic pin 13, the elastic pin 13 is movably inserted in the elastic pin insertion countersunk hole 14, and a gap 16 is arranged between the front side surface of the coupling 12 and the outer side surface of the shaft end of the non-drive end shaft extension 1 of the generator.

[0014] The stator frame 5 of the auxiliary exciter is connected to the outer cover 4 of the non-drive end bearing of the generator through the connecting bolts 15 arranged on the front cover 6 of the auxiliary exciter; eight elastic pin insertion countersunk holes 14 are arranged at equal intervals on the outer side of the shaft end of the non-drive end shaft extension 1 of the generator, and eight elastic pins 13 are arranged at equal intervals on the front side of the coupling 12; during the operation of the generator, when the stator of the generator expands axially, the integral and independent auxiliary exciter arranged on the outer cover of the non-drive end bearing of the generator will also expand synchronously with the expansion of the generator stator in the axial direction, that is, the rotor of the auxiliary exciter will also move with the same expansion amount of the generator stator in the axial direction, but at this time, the expansion amount of the generator rotor in the axial direction that is different from the axial expansion amount of the generator stator in the axial direction is absorbed by the gap 16 arranged between the front side of the coupling 12 and the outer side of the shaft end of the non-drive end shaft extension 1 of the generator, so as not to affect the connection between the auxiliary exciter and the generator rotor.

Claims

1. An integral independent structure auxiliary exciter for resisting different axial expansion amounts of a generator stator and rotor, comprising a generator non-drive end motor end cover (3), a generator non-drive end bearing (2) being arranged in the generator non-drive end motor end cover (3), a generator non-drive end shaft extension (1) being arranged in the generator non-drive end bearing (2), and a generator non-drive end bearing outer cover (4) being arranged on the generator non-drive end bearing (2) outside the generator non-drive end shaft extension (1), characterized in that: An elastic pin insertion countersunk hole (14) is provided on the outer side surface of the shaft end of the non-drive end shaft extension (1) of the generator; an auxiliary exciter stator base (5) is fixedly connected to the non-drive end bearing outer cover (4) of the generator; an auxiliary exciter front end cover (6) and an auxiliary exciter rear end cover (7) are respectively provided on the auxiliary exciter stator base (5); a front end cover bearing (8) is provided on the auxiliary exciter front end cover (6); a rear end cover bearing (9) is provided on the auxiliary exciter rear end cover (7); and a front end cover bearing (8) and a rear end cover bearing (9) are provided on the front end cover bearing (8) and the rear end cover bearing (9). (9) is provided with an auxiliary exciter rotor (10), a front end shaft extension (11) of the auxiliary exciter rotor is provided at the front end of the auxiliary exciter rotor (10), a coupling (12) is provided on the front end shaft extension (11) of the auxiliary exciter rotor, an elastic column pin (13) is provided on the front side of the coupling (12), the elastic column pin (13) is movably inserted in the elastic column pin insertion countersunk hole (14), and a gap (16) is provided between the front side of the coupling (12) and the outer side of the shaft end of the shaft extension (1) of the generator non-driving end.

2. The integral independent structure auxiliary exciter for resisting different axial expansion of the stator and rotor of the generator according to claim 1, characterized in that: The auxiliary exciter stator frame (5) is connected to the generator non-drive end bearing outer cover (4) through a connecting bolt (15) provided on the front end cover (6) of the auxiliary exciter; eight elastic pin insertion countersunk holes (14) are provided at equal intervals on the outer side surface of the shaft end of the generator non-drive end shaft extension (1), and eight elastic pins (13) are provided at equal intervals on the front side surface of the coupling (12).

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