CN104265545A - Integrated oscillating servomotor of water turbine distributor - Google Patents

Abstract

The invention discloses an integrated oscillating servomotor of a water turbine distributor. The integrated oscillating servomotor comprises a servo motor, a servo electric cylinder, a push-pull rod and a base; the servo electric cylinder is driven by the servo motor; one end of the push-pull rod is arranged on a piston arranged inside the servo electric cylinder, while the other end of the push-pull rod extends out of the servo electric cylinder; the end, located outside the servo electric cylinder, of the push-pull rod is connected with a crank arm, and the other end of the crank arm is connected with a control ring; a vertical shaft is arranged at the bottom of the servo electric cylinder; the servo electric cylinder is arranged on the base by use of a radial thrust bearing; a cambered groove matched with the vertical shaft in size is formed in the base in a position corresponding to the vertical shaft, and the vertical shaft penetrates through the cambered groove. The integrated oscillating servomotor of the water turbine distributor is high in integration level, simple in structure, high in working efficiency and precision in control, and therefore, the modern motion control technique, the numerical control technique and the bus (network) technique can be integrated conveniently, programmed bus (network) control can be realized and on-off control work of the water turbine distributor can be effectively completed; the integrated oscillating servomotor of the water turbine distributor is suitable for large, medium and small size conventional hydropower station units and pumped storage power station units.

Description

Integral swinging servomotor for hydraulic turbine water guiding mechanism

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technical field

The invention belongs to the technical field of water turbines, and in particular relates to an integral swing servomotor of a water guiding mechanism of a water turbine.

Background technique

The servomotor, as the power component in the transmission system of the water guide mechanism of the hydraulic turbine, is the executive mechanism of the governor. The quality of its working performance is related to the safe, stable and reliable operation of the hydropower unit. The traditional servomotor is composed of a single straight cylinder and piston, referred to as straight cylinder servomotor. When the turbine load changes, the pressure oil controlled by the main pressure distribution valve of the governor enters the oil cylinder of the servomotor to push the servomotor piston; when the piston moves, the control ring is rotated through the push-pull rod; the control ring then passes through the connecting rod and the rotating arm To achieve the purpose of controlling guide vanes (or needles, paddles, deflectors).

The traditional straight cylinder servomotor has the following defects and deficiencies: (1) The piston moves linearly in the cylinder, and the push-pull rod rotates around the piston to realize the connection between the linear motion of the piston and the arc motion of the control ring. Due to the swing of the push-pull rod in the cylinder, the push/pull force of the piston acting on the push-pull rod is not in the same direction as the linear motion of the push-pull rod, that is, only part of the output power of the piston is applied to the guide vane, and another part of the power is applied to the guide vane. consumes itself. On the one hand, this will reduce the efficiency of the servomotor and increase energy consumption; on the other hand, the force on the piston will be unreasonable, which will easily cause problems such as deformation, jamming, and oil leakage; (2) It is difficult to realize the hydraulic servo system The precise control of thrust, speed and position is not easy to integrate with modern motion control technology, numerical control technology and bus (network) technology to realize the programming and bus (network) control of the servomotor; (3) due to ( 1) and (2) Two defects and deficiencies make it difficult to measure the stroke of the servomotor, so the stroke measurement and feedback devices are generally not installed on the traditional servomotor, which is not convenient for the governor to adjust the operation of the unit.

The above defects and deficiencies of the traditional servomotor restrict the function of the governor. Therefore, in order to realize the safe, reliable, fast and sensitive control of the water guiding mechanism of the water turbine, it is necessary to overcome the above defects and deficiencies, and design a more advanced, more practical and more efficient servomotor.

Contents of the invention

Aiming at the deficiencies in the prior art, the present invention provides an integral swing servomotor for the water guide mechanism of the water turbine. The servomotor can also clearly connect the arc motion of the control ring with the linear motion of the push-pull rod under the premise of ensuring a reasonable connection. Improve the efficiency of the servomotor, improve the force condition of the push-pull rod, and improve the control precision of the servomotor.

In order to solve the problems of the technologies described above, the present invention adopts the following technical solutions:

The overall swing servomotor of the water guide mechanism of the water turbine includes a servo motor, a servo electric cylinder, a push-pull rod and a base, and the servo motor drives the servo electric cylinder; Outside the electric cylinder, one end of the push-pull rod located outside the servo electric cylinder is connected to the crank arm, and the other end of the crank arm is connected to the control ring; there is a vertical shaft at the bottom of the servo electric cylinder, and the servo electric cylinder is placed on the base through radial thrust bearings. An arc-shaped groove matching the size of the vertical axis is formed at a position corresponding to the vertical axis, and the vertical axis passes through the arc-shaped groove.

One end of the above-mentioned push-pull rod located outside the servo electric cylinder is connected with the crank arm through the fork and the matched fork pin.

A limit pin and a limit sensor are arranged on the crank arm or the control ring.

In order to realize the precise measurement and feedback of the stroke of the servomotor, the preferred solution of the present invention also includes a stroke sensor. The stroke sensor includes a stroke sensor cylinder and a stroke rod arranged at the end of the stroke sensor cylinder. On the servo electric cylinder, the stroke rod and the push-pull rod move synchronously.

The stroke rod is parallel to the push-pull rod, and the end of the stroke rod that is not connected to the stroke sensor cylinder is fixedly connected to the push-pull rod.

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Compared with the traditional straight cylinder servomotor, the present invention has the following characteristics and beneficial effects:

1. The thrust and pulling force received by the push-pull rod in the servomotor of the present invention are always consistent with the linear motion direction of the push-pull rod. On the one hand, it can reduce energy consumption and improve the efficiency of the servomotor; on the other hand, the push-pull rod has good stress conditions, avoiding Eliminate the phenomenon of piston deformation, jamming, oil leakage and other phenomena caused by unreasonable acceptance.

2. The electric servo system can realize the precise control of the push-pull force, speed and position of the push-pull rod.

3. The stroke sensor is used to realize the real-time measurement of the stroke of the servomotor, which is convenient for adjusting the governor according to the actual situation.

4. Simple structure, high integration, high work efficiency, precise control, easy to integrate modern motion control technology, numerical control technology and bus (network) technology, realize programmatic and bus (network) control, and effectively complete the water guiding of the turbine The opening and closing control work of the mechanism is suitable for large, medium and small conventional hydropower station units and pumped storage power station units.

Description of drawings

Fig. 1 is the specific structural schematic diagram of servomotor of the present invention;

Fig. 2 is a top view of the servomotor in Fig. 1;

Fig. 3 is a side view of the servomotor in Fig. 1;

Fig. 4 is a bottom view of the servomotor in Fig. 1 .

In the figure, 1-servo motor, 2-servo electric cylinder, 3-push-pull rod, 4-stroke sensor cylinder, 5-stroke rod, 6-fork, 7-fork pin, 8-knob, 9-limit Position pin, 10-control ring, 11-base, 12-vertical shaft, 13-arc groove, 14-radial thrust bearing, 15-signal line, 16-limit sensor.

Detailed ways

The technical solution of the present invention will be further described below in conjunction with the accompanying drawings.

See Figures 1 to 4. In this specific implementation, the servomotor includes a servo motor (1), a servo electric cylinder (2), a push-pull rod (3), a travel sensor and a base (11), and the travel sensor includes a travel sensor cylinder (4 ) and the travel rod (5) located at the end of the travel sensor cylinder (4). The servo motor (1), the servo electric cylinder (2), and the push-pull rod (3) are connected in sequence, and the central axes of the three are collinear. The servo motor (1) is located at the rear of the servomotor, the push-pull rod (3) is located at the front of the servomotor, the servo electric cylinder (2) is in the center, and its two ends are respectively connected to the servo motor (1) and the push-pull rod (3), the servo motor ( 1) It is used to drive the servo electric cylinder (2). One end of the push-pull rod (3) is set on the internal piston of the servo electric cylinder (2), and the other end passes out of the servo electric cylinder (2).

The stroke sensor cylinder (4) is fixed on the top of the servo electric cylinder (2), and the end of the stroke rod (5) that is not connected to the stroke sensor cylinder (4) is fixed on the push-pull rod (3) outside the servo electric cylinder (2). At one end, when the push-pull rod (3) moves linearly, the stroke rod (5) moves synchronously with the push-pull rod (3), and the stroke of the stroke rod (5) is the stroke of the push-pull rod (3). When the servomotor is working, the positions of the servo motor (1) and the servo electric cylinder (2) are relatively fixed, and the push-pull rod (3) performs linear telescopic motion relative to the servo motor (1) and the servo electric cylinder (2).

The bottom end of the servo electric cylinder (2) is provided with a vertical shaft (12), and the base (11) is provided with an arc-shaped slot (13) corresponding to the position of the vertical shaft (12), and the arc-shaped slot (13) is slightly larger than the vertical The diameter of the shaft (12), the servo electric cylinder (2) is placed on the base (11) through the radial thrust bearing (14), the radial thrust bearing (14) is located at the front end of the bottom of the servo electric cylinder (2), and is located on the servo The vertical shaft (12) at the base end of the electric cylinder (2) passes through the arc-shaped slot (13). The servo electric cylinder (2) can swing around the radial thrust bearing (14) relative to the base (11), and the arc-shaped groove (13) is used to regulate the overall swing of the servomotor around the radial thrust bearing (14).

The end of the push-pull rod (3) is connected to the crank arm (8) through the fork (6) and the matching fork pin (7), and the other end of the crank arm (8) is connected to the control ring (10), and the control ring (10) is also connected to the The rod and the rotating arm drive the guide vane to rotate through the connecting rod and the rotating arm.

The stroke sensor feeds back the collected data to the controller through the signal line (15), obtains the real-time stroke based on the feedback data, and adjusts the governor command according to the feedback data.

Preferably, a limit pin (9) and a limit sensor (16) can be arranged on the crank arm (8) or the control ring (10), so as to avoid over-pushing and over-pulling of the servomotor, thereby causing damage to the guide vane.

The working principle of the servomotor of the present invention is as follows:

When the load of the turbine changes, the governor sends the travel sensor the movement law of the push-pull rod, that is, the relationship between the travel and time. According to the movement law of the push-pull rod, the servo motor converts the rotary motion of the servo motor into the linear motion of the push-pull rod through the mechanical motion of the screw and the screw pair through the electric drive system and linear actuator in the servo electric cylinder, and then uses the servo The closed-loop control feature of the motor provides precise control of thrust, speed and position. When the push-pull rod moves linearly relative to the servo electric cylinder and pushes the crank arm to make a circular motion, the servo electric cylinder will automatically swing around the radial thrust bearing to realize the transformation from the linear motion of the push-pull rod to the circular motion of the crank arm and the push-pull force transmission.

During the above process, the push and pull force received by the push-pull rod is always in the same direction as the linear movement direction of the push-pull rod, so the force condition of the push-pull rod is good, which can improve the working efficiency of the servo motor and reduce energy consumption.

Claims (5)

1. turbine gate mechanism integrated oscillating type servomotor, is characterized in that, comprising:

Actuating motor, servo electric jar, pull bar and base, driven by servomotor servo electric jar; Pull bar one end is located in servo electric jar and is established on piston, and its other end passes outside servo electric jar, and one end that pull bar is positioned at outside servo electric jar connects connecting lever, connecting lever the other end connection control ring; Be provided with vertical axis bottom servo electric jar, servo electric jar is placed on base by radial-thrust bearing, base has the curve bath mated with vertical axis size with vertical axis corresponding position, and vertical axis is through curve bath.

2. turbine gate mechanism integrated oscillating type servomotor as claimed in claim 1, is characterized in that:

One end that described pull bar is positioned at outside servo electric jar is connected with connecting lever by the jaw pin of jaw and coupling.

3. turbine gate mechanism integrated oscillating type servomotor as claimed in claim 1, is characterized in that:

Described connecting lever or control ring are provided with position limit pin and limit sensors.

4. turbine gate mechanism integrated oscillating type servomotor as claimed in claim 1, is characterized in that:

Also comprise stroke sensor, described stroke sensor comprises stroke sensor cylinder body and is located at the stroke lever of stroke sensor cylinder body termination, and stroke sensor cylinder body is located on servo electric jar, and stroke lever and pull bar are synchronized with the movement.

5. turbine gate mechanism integrated oscillating type servomotor as claimed in claim 4, is characterized in that:

Described stroke lever is parallel with pull bar, and the termination that stroke lever is not connected with stroke sensor cylinder body is fixedly connected with pull bar.