Lever device of a hydrogenerator governor and its usage method

Abstract

The present invention provides a lever device and a usage method for a governor of a water turbine generator set, which includes a lever, a connecting mechanism, a restoring mechanism, and a driving mechanism. One end of the lever is provided with a hinged connecting rod. The end of the connecting rod is connected to a pilot valve through the connecting mechanism. The other end of the lever is hinged to the driving mechanism. The driving mechanism drives the lever to rotate, driving the pilot valve to switch for speed regulation. The middle of the lever is hinged to the restoring mechanism, and the restoring mechanism drives the lever to rotate to drive the pilot valve to switch for resetting. A universal bearing is provided in the connecting seat of the connecting mechanism. The universal bearing is fixed in the connecting seat through a limiting block. The limiting block is threadedly connected to the connecting seat. The end of the connecting rod is fixedly connected to the universal bearing. The pilot valve is fixedly connected to the connecting seat through a taper pin. It solves the problem of automatically controlling the movement and reset of the pilot valve, and effectively avoids the jamming of the pilot valve.

Description

Technical Field

[0001] The present invention relates to the technical field of water turbine units, and particularly relates to a lever device and a usage method of a governor for a hydro-generating unit. Background Art

[0002] For a power station water turbine governor to regulate speed, it is necessary to increase or decrease the load of the unit, control the movement of the guide valve to switch the oil circuit, thereby adjusting the position of the guide vane. After the adjustment is completed, the guide valve needs to be reset. The existing adjustment system cannot automatically control the movement and reset of the guide valve, and the position feedback of the guide vane cannot be displayed either.

[0003] The existing connection method between the guide valve and the connecting rod is a split spherical head bearing structure. During the unit load adjustment process, when the axial driving force of the connecting rod increases, the pressure of the spherical head bearing friction pair increases, resulting in an increase in friction force, which causes defects such as inflexible steering of the spherical head bearing, small commutation angle, and jamming, resulting in obstacles to the transmission of the driving force of the guide valve, inducing faults such as jamming of the guide valve, and causing the speed regulation system to malfunction, seriously threatening the safe and stable operation of the unit. Summary of the Invention

[0004] The main purpose of the present invention is to provide a lever device and a usage method of a governor for a hydro-generating unit to solve the problems in the above background art.

[0005] To solve the above technical problems, the technical solution adopted by the present invention is: it includes a lever, a connection mechanism, a return mechanism, and a driving mechanism. One end of the lever is provided with a hinged connecting rod. The end of the connecting rod is connected to the guide valve through the connection mechanism. The other end of the lever is hinged to the driving mechanism. The driving mechanism drives the lever to rotate to drive the guide valve to switch for speed regulation. The middle of the lever is hinged to the return mechanism, and the return mechanism drives the lever to rotate to drive the guide valve to switch for resetting;

[0006] A universal bearing is provided in the connection seat of the connection mechanism. The universal bearing is fixed in the connection seat through a limit block. The limit block is threadedly connected to the connection seat. The end of the connecting rod is fixedly connected to the universal bearing. The guide valve is fixedly connected to the connection seat through a taper pin.

[0007] Preferably, the driving mechanism includes a first lead screw, a stepping motor, a first handwheel, and a sensor;

[0008] The stepping motor and the first handwheel are used to drive the first lead screw to rotate, and the sensor is used to monitor the number of rotations of the first lead screw;

[0009] The lever is connected to the first lead screw through a lead screw sleeve. The lead screw sleeve is threadedly connected to the first lead screw. The end of the lever is hinged to the lead screw sleeve.

[0010] Preferably, the return mechanism includes a rotating shaft, an upper return arm, a yield link, and a secondary return arm;

[0011] The upper return arm and the auxiliary return arm are fixed on the rotating shaft. One end of the yield link is hinged to the upper return arm, and the other end is hinged to the middle of the lever. The auxiliary return arm is connected to the guide vane through a link pulley mechanism. A guide vane position display mechanism is also fixedly installed at the end of the rotating shaft.

[0012] Preferably, the link pulley mechanism includes a main return arm, a fixed support, a weight, a steel wire rope, a pulley and a coupling shaft;

[0013] The middle of the main return arm abuts against the fixed support and rotates. One end of the main return arm is hinged to the auxiliary return arm through a coupling shaft, and the other end of the main return arm is connected to the guide vane through a steel wire rope.

[0014] Preferably, the steel wire rope abuts against the pulley and moves, and the weight is suspended at one end of the steel wire rope of the main return arm.

[0015] Preferably, the guide vane position display mechanism includes an indicator board and a pointer. The pointer is fixed on the rotating shaft and rotates in front of the indicator board.

[0016] Preferably, a manual driving mechanism is also provided. The manual driving mechanism includes a second lead screw and a second hand wheel. The second hand wheel drives the second lead screw to rotate. The end of the second lead screw is located below the lever. The manual driving mechanism is arranged on the opposite side of the driving mechanism and acts on both ends of the lever respectively.

[0017] The method is as follows: S1. When the unit increases the load, the first lead screw is driven to rotate by a stepping motor, so as to drive the lever to rotate with the yield link as the fulcrum, drive the link and the pilot valve to move downward, and open the oil port of the control oil source;

[0018] S2. The spool of the main servomotor moves downward, opens the oil port of the closing cavity, and pushes the guide vane to open through the pressure oil in the opening cavity, so as to increase the water flow and load of the runner;

[0019] S3. During the opening process of the guide vane, the position of the guide vane is feedback through the return mechanism, and the lever can be driven to rotate with the first lead screw as the fulcrum through the connection of the yield link, and the link and the pilot valve are driven to move upward for reset, completing the load regulation;

[0020] S4. When the unit reduces the load, the stepping motor is driven in the reverse direction to drive the link and the pilot valve to move upward, so as to perform the load reduction adjustment.

[0021] The present invention provides a lever device and a usage method of a governor of a hydro-generating unit, and the beneficial effects are as follows:

[0022] 1. It can automatically drive the pilot valve to move through the driving mechanism, so as to switch the oil circuit, thereby adjusting the position of the guide vane and performing speed regulation;

[0023] 2. After the speed regulation is completed, the guiding valve can be automatically reset by the return mechanism, and at the same time, the position of the guide vane can be real-time feedback;

[0024] 3. The manual driving mechanism can manually drive the lever to move, thereby driving the guiding valve to reset;

[0025] 4. The universal bearing in the connecting mechanism drives the connecting rod to rotate flexibly, with a large commutation angle, effectively avoiding jamming of the guiding valve. Brief Description of the Drawings

[0026] The present invention will be further described below in conjunction with the drawings and embodiments:

[0027] Figure 1 is a schematic diagram of the overall structure connection of the present invention;

[0028] Figure 2 is a front sectional view of the connecting mechanism of the present invention;

[0029] Figure 3 is a schematic diagram of the increased load drive of the present invention;

[0030] Figure 4 is a schematic diagram of the return drive after the increased load of the present invention;

[0031] In the figure: guiding valve 1; connecting mechanism 2; connecting seat 201; taper pin 202; limit block 203; universal bearing 204; connecting rod 3; lever 4; yield connecting rod 5; first lead screw 6; sensor 7; stepping motor 8; first handwheel 9; upper return arm 10; indicator plate 11; pointer 12; second lead screw 13; second handwheel 14; fixed support 15; weight 16; main return arm 17; coupling shaft 18; auxiliary return arm 19; rotating shaft 20; pulley 21; steel wire rope 22. Detailed Embodiment

[0032] Embodiment 1

[0033] As Figures 1 to 4 shown, a lever device and a usage method of a hydrogenerator governor include a lever 4, a connecting mechanism 2, a return mechanism and a driving mechanism. One end of the lever 4 is provided with a hinged connecting rod 3. The end of the connecting rod 3 is connected to the guiding valve 1 through the connecting mechanism 2. The other end of the lever 4 is hinged to the driving mechanism. By driving the lever 4 to rotate by the driving mechanism, the guiding valve 1 is switched to perform speed regulation. The middle of the lever 4 is hinged to the return mechanism. By driving the lever 4 to rotate by the return mechanism, the guiding valve 1 is switched to perform reset;

[0034] The connecting seat 201 in the connecting mechanism 2 is provided with a universal bearing 204. The universal bearing 204 is fixed in the connecting seat 201 through a limit block 203. The limit block 203 is threadedly connected to the connecting seat 201. The end of the connecting rod 3 is fixedly connected to the universal bearing 204. The guide valve 1 is fixedly connected to the connecting seat 201 through a taper pin 202. With this structure, when the guide vane opening is 50% of the static balance position opening, theoretically, the connection center of the connecting rod 3 and the lever 4 is on the extension line of the axis of the guide valve 1. At this time, the force acting on the guide valve 1 through the connecting rod 3 only has a vertical component force and no horizontal component force, and the guide valve 1 will not have the phenomenon of jamming due to being stuck. Once the guide vane deviates from the 50% opening, the connection center of the connecting rod 3 and the lever 4 is not on the extension line of the axis of the guide valve 1. The force acting on the guide valve 1 through the connecting rod 3 has not only a vertical component force but also a horizontal component force. The connecting mechanism 2 first acts the force of the connecting rod 3 on the universal bearing 204, and uses the characteristics of the large commutation angle and flexible circumferential rotation of the universal bearing 204 to ensure the smooth transmission of the driving force of the guide valve 1 and reduce or even eliminate the problem of jamming of the guide valve 1.

[0035] Preferably, the first lead screw 6, the stepping motor 8, the first handwheel 9 and the sensor 7 in the driving mechanism;

[0036] The stepping motor 8 and the first handwheel 9 are used to drive the first lead screw 6 to rotate, and the sensor 7 is used to monitor the number of turns of the first lead screw 6;

[0037] The lever 4 is connected to the first lead screw 6 through a wire sleeve. The wire sleeve is threadedly connected to the first lead screw 6. The end of the lever 4 is hinged to the wire sleeve. With this structure, the stepping motor 8 drives the first lead screw 6 to rotate, thereby driving the lever 4 to rotate with the connection point of the yield link 5 as the fulcrum, and thus driving the guide valve 1 to move.

[0038] Preferably, the restoring mechanism includes a rotating shaft 20, an upper restoring arm 10, a yield link 5 and a secondary restoring arm 19;

[0039] The upper restoring arm 10 and the secondary restoring arm 19 are fixed on the rotating shaft 20. One end of the yield link 5 is hinged to the upper restoring arm 10, and the other end is hinged to the middle of the lever 4. The secondary restoring arm 19 is connected to the guide vane through a connecting rod pulley mechanism. A guide vane position display mechanism is also fixedly provided at the end of the rotating shaft 20. With this structure, the position of the guide vane is real-time fed back to the secondary restoring arm 19 through the connecting rod pulley mechanism, thereby driving the secondary restoring arm 19 and the rotating shaft 20 to rotate, and can be real-time displayed on the guide vane position display mechanism. While the rotating shaft 20 rotates, the upper restoring arm 10 can drive the lever 4 to rotate with the first lead screw 6 as the fulcrum, thereby driving the guide valve 1 to move back to its original position.

[0040] Preferably, the connecting rod pulley mechanism includes a main restoring arm 17, a fixed support 15, a weight 16, a steel wire rope 22, a pulley 21 and a coupling shaft 18;

[0041] The middle part of the main return arm 17 abuts against the fixed support 15 and rotates. One end of the main return arm 17 is hinged to the auxiliary return arm 19 through a coupling shaft 18, and the other end of the main return arm 17 is connected to the guide vane through a steel wire rope 22. With this structure, the position of the guide vane is fed back to the main return arm 17 through the steel wire rope 22 and then fed back to the auxiliary return arm 19 through the coupling shaft 18.

[0042] Preferably, the steel wire rope 22 abuts against the pulley 21 and moves, and the weight 16 is suspended at one end of the steel wire rope 22 of the main return arm 17. With this structure, the steel wire rope 22 is fixed to the guide vane. When the guide vane moves, it drives the steel wire rope 22 to move. The weight 16 acts as a load, making the movement of the steel wire rope 22 synchronous with the rotation of the main return arm 17.

[0043] Preferably, the guide vane position display mechanism includes an indicator plate 11 and a pointer 12. The pointer 12 is fixed on the rotating shaft 20 and rotates in front of the indicator plate 11. With this structure, when the guide vane moves, it can be fed back to the rotating shaft 20 to make it rotate, thereby changing the position of the pointer 12 on the indicator plate 11, so as to display the position of the guide vane.

[0044] Preferably, a manual driving mechanism is also provided. The manual driving mechanism includes a second lead screw 13 and a second hand wheel 14. The second hand wheel 14 drives the second lead screw 13 to rotate. The end of the second lead screw 13 is located below the lever 4. The manual driving mechanism is arranged on the opposite side of the driving mechanism and acts on both ends of the lever 4 respectively. With this structure, after the reset mechanism fails, the second hand wheel 14 can be driven to drive the second lead screw 13 to move, thereby lifting the lever 4 upward to move, causing the pilot valve 1 to move and reset. Usually, the second lead screw 13 is located below the lever 4 and does not affect the normal rotation of the lever 4.

[0045] Embodiment 2

[0046] As Figures 1 to 4 shown, further described in combination with Embodiment 1: When the unit increases the load, the first lead screw 6 is driven to rotate by the stepping motor 8, thereby driving the lever 4 to rotate with the yield link 5 as the fulcrum, driving the link 3 and the pilot valve 1 to move downward, opening the oil port of the control oil source, as Figure 3 shown; the main relay valve spool moves downward, opening the oil port of the closing cavity. The opening cavity pressure oil is used to push the guide vane to open, thereby increasing the water flow and load of the runner; during the opening process of the guide vane, the position of the guide vane is fed back through the return mechanism, and the lever 4 can be driven to rotate with the first lead screw 6 as the fulcrum through the connection of the yield link 5, driving the link 3 and the pilot valve 1 to move upward for reset, as Figure 4 shown, completing the load regulation; when the unit reduces the load, the stepping motor 8 is driven in the reverse direction, driving the link 3 and the pilot valve 1 to move upward, thereby performing the load reduction regulation.

[0047] The above embodiments are only the preferred technical solutions of the present invention and should not be regarded as limitations on the present invention. The protection scope of the present invention shall be the technical solutions recorded in the claims, including the equivalent replacement solutions of the technical features in the technical solutions recorded in the claims. That is, equivalent replacement improvements within this scope are also within the protection scope of the present invention.

Claims

1. A lever device for a governor of a water turbine generator set, characterized in that: It includes a lever (4), a connecting mechanism (2), a restoring mechanism and a driving mechanism. One end of the lever (4) is hinged with a connecting rod (3). The end of the connecting rod (3) is connected to the pilot valve (1) through the connecting mechanism (2). The other end of the lever (4) is hinged with the driving mechanism. The driving mechanism drives the lever (4) to rotate to drive the pilot valve (1) to switch so as to adjust the speed. The middle part of the lever (4) is hinged with the restoring mechanism. The restoring mechanism drives the lever (4) to rotate to drive the pilot valve (1) to switch for resetting; A universal bearing (204) is arranged in a connecting seat (201) of the connecting mechanism (2). The universal bearing (204) is fixed in the connecting seat (201) through a limiting block (203). The limiting block (203) is threadedly connected to the connecting seat (201). The end of the connecting rod (3) is fixedly connected to the universal bearing (204). The pilot valve (1) is fixedly connected to the connecting seat (201) through a taper pin (202); The restoring mechanism includes a rotating shaft (20), an upper restoring arm (10), a yielding connecting rod (5) and a secondary restoring arm (19); The upper restoring arm (10) and the secondary restoring arm (19) are fixed on the rotating shaft (20). One end of the yielding connecting rod (5) is hinged to the upper restoring arm (10), and the other end is hinged to the middle part of the lever (4). The secondary restoring arm (19) is connected to the guide vane through a connecting rod pulley mechanism. A guide vane position display mechanism is also fixedly arranged at the end of the rotating shaft (20).

2. The lever device of a hydro-generator governor according to claim 1, wherein: The driving mechanism includes a first lead screw (6), a stepping motor (8), a first handwheel (9) and a sensor (7); The stepping motor (8) and the first handwheel (9) are used to drive the first lead screw (6) to rotate. The sensor (7) is used to monitor the number of rotations of the first lead screw (6); The lever (4) is connected to the first lead screw (6) through a lead screw sleeve. The lead screw sleeve is threadedly connected to the first lead screw (6). The end of the lever (4) is hinged to the lead screw sleeve.

3. The lever device of a hydrogenerator governor according to claim 1, characterized in that: The connecting rod pulley mechanism includes a main restoring arm (17), a fixed support (15), a weight (16), a steel wire rope (22), a pulley (21) and a coupling shaft (18); The middle part of the main restoring arm (17) abuts against the fixed support (15) and rotates. One end of the main restoring arm (17) is hinged to the secondary restoring arm (19) through the coupling shaft (18). The other end of the main restoring arm (17) is connected to the guide vane through the steel wire rope (22).

4. The lever device of a hydrogenerator governor according to claim 3, characterized in that: The steel wire rope (22) abuts against the pulley (21) and moves. The weight (16) is suspended at one end of the steel wire rope (22) of the main restoring arm (17).

5. The lever device of a hydrogenerator governor according to claim 1, characterized in that: The guide vane position display mechanism includes an indicator board (11) and a pointer (12). The pointer (12) is fixed on the rotating shaft (20). The pointer (12) rotates in front of the indicator board (11).

6. The lever device of a hydrogenerator governor according to claim 1, characterized in that: A manual driving mechanism is also provided. The manual driving mechanism includes a second lead screw (13) and a second handwheel (14). The second handwheel (14) drives the second lead screw (13) to rotate. The end of the second lead screw (13) is located below the lever (4). The manual driving mechanism is arranged on the opposite side of the driving mechanism and acts on both ends of the lever (4) respectively.

7. The usage method of the lever device of a hydrogenerator governor according to any one of claims 1 to 6 is as follows: S1. When the unit increases the load, the first lead screw (6) is driven to rotate by the stepper motor (8), thereby driving the lever (4) to rotate with the yield link (5) as the fulcrum, driving the connecting rod (3) and the pilot valve (1) to move downward, and opening the oil port of the control oil source; S2. The spool of the main pressure regulating valve moves downward, opening the oil port of the closing chamber. The guide vane is pushed to open by the pressure oil in the opening chamber, thereby increasing the water flow and load of the runner; S3. During the opening process of the guide vane, the position of the guide vane is feedback through the restoring mechanism, and the lever (4) can be driven to rotate with the first lead screw (6) as the fulcrum through the connection of the yield link (5), driving the connecting rod (3) and the pilot valve (1) to move upward for resetting, and completing the adjustment of the load; S4. When the unit reduces the load, the stepper motor (8) is driven in the reverse direction, driving the connecting rod (3) and the pilot valve (1) to move upward, thereby performing the load reduction adjustment.

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