CN103470663B - Wear sensor for friction plate of fan yaw brake - Google Patents

Abstract

The invention relates to a component of a wind power generator, in particular to a sensor used for measuring the wear degree of a wind turbine yaw brake friction plate. A wind turbine yaw brake friction plate wear sensor, including a push rod, a spring, a housing, a limit part, a micro switch and a wire, the micro switch is arranged inside the housing, and the wire is electrically connected to the micro switch and passes through one end of the housing , the transmission element of the micro switch is in close contact with one end of the ejector rod, and the other end of the ejector rod passes through the housing; the ejector rod passes through the inside of the spring and the end of the spring away from the micro switch is fixedly connected with the ejector rod; the limit part is fixedly set Inside the housing and between the micro switch and the spring, the push rod passes through the through hole on the limit part, and the diameter of the through hole is smaller than the diameter of the spring, and the end of the spring close to the micro switch is connected to the limit. parts in close contact. The wire includes two wires, one is a power wire; the other is a signal wire, which is connected to the electric control system of the fan.

Description

Wind turbine yaw brake friction plate wear sensor

technical field

The invention relates to a component of a wind power generator, in particular to a sensor used for measuring the wear degree of a wind turbine yaw brake friction plate.

Background technique

The working principle of the wind power generator using the traditional doubly-fed generator (referred to as fan in the present invention) is: the wind pushes the blades to rotate, thereby driving the low-speed shaft on the impeller to rotate. Through a speed-increasing gearbox, the low speed of the low-speed shaft is increased to the high speed required by the generator to generate electricity, thereby driving the generator to generate electricity.

Since the wind direction of the wind field is constantly changing, in order to utilize wind energy efficiently, the rotor blades of the fan must always be aligned with the wind direction during operation. For this reason, a yaw system is installed on the top of the wind turbine inner tower. As one of the important components of the wind turbine control system, the yaw system's main function is to correctly adjust the windward direction of the unit according to the operating conditions of the wind turbine.

The hardware system of the yaw system is mainly composed of yaw motor, reducer, yaw motor electromagnetic brake, yaw brake and cable sensor. The yaw brake is a hydraulic disc type, and the pressure of 140-160bar is provided by the hydraulic system to provide sufficient braking force. When yawing, the hydraulic pressure is released but a certain residual pressure is maintained, and a certain damping moment is maintained during the yaw process, thereby reducing the impact load of the fan during the yaw process.

During the yaw process of the wind turbine, under a certain oil pressure, the two friction plates of the yaw brake are clamped on both sides of the yaw brake disc and rotate relative to each other, providing a certain damping torque, but at the same time this causes friction Chip wear. If the working conditions are normal, the material properties of the friction plate are excellent, the wear amount of the friction plate is very small, and the life of the friction plate is very long, and the life span of more than 5 years is very common, so the wear amount of the friction plate does not need to be checked frequently.

However, there may be various problems in the wind turbine, such as poor precision, or problems with the design of the wind turbine, or errors in the yaw logic setting parameters, etc., which will cause the yaw friction plate to work under abnormal conditions. As a result, the friction plate is severely worn, and the friction material is worn out in a short time. If it is not checked in time, the steel base plate and the brake disc will be in direct contact with the friction after the friction material of the friction plate is worn out, resulting in damage to the surface of the brake disc.

Since wind turbines are mostly installed in remote fields, and the nacelle is located at the top of a tower tens of meters high, once the brake disc is damaged, the entire nacelle needs to be hoisted to replace the brake disc, which is very expensive. Therefore, how to check and monitor the wear of the yaw friction plate to avoid damage to the brake disc is an urgent problem to be solved for the wind turbine yaw system.

At present, to observe and monitor the wear of the friction lining of the yaw brake, the friction lining wear indicator rod device is mainly used:

As shown in FIG. 1 , the friction plate includes two parts, the friction plate bottom plate 11 (usually a steel plate) and the friction material plate 12 . The friction material plate 12 is in contact with the brake disc 4 . The friction lining wear indicating rod 2 is fully tightened on the friction lining bottom plate 11, and the top of the friction lining wearing indicating rod 2 is the distance C (braking state) from the top of the friction lining wearing indicating rod 2 to the brake caliper 5 caliper.

Working principle: as the thickness 9 of the friction material plate 12 wears continuously, the exposed part C of the friction plate wear indicator rod 2 will always decrease, and the reduced amount is the wear amount of the friction plate. When the top of the friction lining wear indicator rod 2 is flush with the brake caliper 5 caliper body, the friction material plate 12 has 2mm remaining, indicating that the friction lining needs to be replaced.

The problems of the friction plate wear indicating rod device are as follows:

The friction plate wear indicator stick is only used for manual observation and cannot be automatically detected and controlled. Since the yaw brake is located in the engine room at an altitude of tens of meters, the intervals for maintenance and observation by maintenance personnel are relatively long. For some wind turbines with abnormal working conditions, the friction plate wears out quickly, and it may not be discovered in time when the wear reaches the limit, resulting in The surface of the brake disc is damaged.

Due to the installation space, the friction lining wear indicator rod installed on the upper part of the brake caliper is not easy to be observed.

Due to the existence of the installation error and the processing error of the thickness of the brake caliper shell, the position of the wear indicator rod of the friction lining has a large error, which cannot accurately reflect the actual wear value of the friction lining.

Contents of the invention

The technical problem to be solved by the present invention is to provide a safe and practical wind turbine yaw brake friction plate wear sensor that can reliably and automatically alarm when the friction plate wears to the limit.

In order to realize the foregoing invention object, the present invention provides following technical scheme:

Fan yaw brake friction plate wear sensor, including push rod, spring, housing, limit part, micro switch and wire,

The micro switch is arranged inside the housing, and the wire is electrically connected to the micro switch and passes through one end of the housing;

The transmission element of the micro switch is in close contact with one end of the ejector rod, and the other end of the ejector rod passes through the casing;

The push rod passes through the inside of the spring and the end of the spring away from the micro switch is fixedly connected to the push rod;

The limiting part is fixedly arranged inside the housing and is located between the micro switch and the spring, the push rod passes through the through hole on the limiting part, and the diameter of the through hole is smaller than The diameter of the spring is that the end of the spring close to the micro switch is in close contact with the limiting part.

The wires include at least two wires, one is connected to 5-12V DC for the power line; the other is a signal wire, which is connected to the electric control system (such as PLC) of the entire fan.

The transmission element of the micro switch refers to the part of the micro switch used to trigger the micro switch. Common forms include push pins, buttons, levers, rollers, etc. The transmission element can transmit external force to the movable contact, so as to realize quick connection or disconnection of the movable contact and the fixed contact.

The micro switch is a normally closed micro travel switch.

The limiting part is in the shape of a circular or polygonal plate with a through hole.

The housing includes a first housing and a second housing that are detachably connected, and the first housing and the second housing are both composed of two cylindrical or prismatic hollow tubes with different diameters,

When the first shell is connected to the second shell, the hollow tube with a larger diameter in the first shell is connected with the hollow tube with a larger diameter in the second shell. The connection mode of the first shell and the second shell facilitates the disassembly of the shells, so as to install and disassemble the components inside the shells.

The inside of the housing is also provided with a micro-switch support part, the micro-switch support part is detachably connected to the housing, and the micro-switch penetrating support part is covered and detachably connected to the outside of the middle part of the micro-switch . The micro switch supporting part can make the position of the micro switch fixed, and it is easy to disassemble.

The friction plate wear sensor of the fan yaw brake of the present invention has the following beneficial effects:

1. It truly realizes reliable automatic alarm when the yaw brake friction plate wears to the limit. The operator can get the alarm signal in the operating room, without the need to climb a tower tens of meters high for manual observation.

2. Adopt normally closed miniature travel switch. Since the service life of the friction plate is as long as several years, that is to say, the switch may not be triggered for several years, so accidental disconnection is prone to occur in such a long period of time. When the disconnection occurs, the normally closed signal is triggered to alarm, and the disconnection fault can be detected and eliminated in time. If the normally open signal is used, the alarm cannot be given once the wire is broken, the sensor will fail, and the fault cannot be eliminated in advance, resulting in no alarm when the friction plate is worn out, and accidents cannot be avoided.

3. The wear sensor of the friction plate of the wind turbine yaw brake of the present invention is installed on the side of the brake caliper, which is conducive to wiring and avoiding accidental bumps. If mounted on the back, with the sensor facing the center of the tower, people up and down could touch and damage the sensor.

4. The mechanical sensor has high reliability. Moreover, due to the mechanical isolation of the micro switch and the ejector rod, the electric control system of the fan has no conductive connection with the brake disc itself, which avoids damage to the electric control system of the fan in case of lightning strikes or short circuits.

5. Compact structure, small installation space.

6. Simple structure, few parts and low cost.

Description of drawings

Figure 1 is a schematic diagram of the friction plate wear indicator rod device;

Fig. 2 is a structural schematic diagram of the friction plate wear sensor of the fan yaw brake of the present invention;

Fig. 3 is a schematic diagram of the installation of the friction plate wear sensor of the fan yaw brake of the present invention;

11 Friction plate bottom plate, 12 Friction material plate, 2 Friction plate wear indicator rod, 31 Push rod, 32 Spring, 33 Housing, 331 First housing, 332 Second housing, 34 Limiting part, 35 Micro switch, 351 Micro switch support part, 36 wires, 4 brake discs, 5 brake calipers, 9 friction plate thickness, C The distance from the top of the friction plate wear indicator rod to the flat plane of the brake caliper body (braking state).

Detailed ways

As shown in Fig. 3 and Fig. 2, a wind turbine yaw brake friction plate wear sensor includes a push rod 31, a spring 32, a housing 33, a limiting part 34, a micro switch 35 and a wire 36.

The housing 33 includes a first housing 331 and a second housing 332 that are detachably connected, and the connection may be threaded. Both the first housing 331 and the second housing 332 are composed of two cylindrical or square cylindrical hollow tubes with different diameters.

When the first housing 331 and the second housing are connected, the hollow tube with a larger diameter of the first housing 331 is connected with the hollow tube with a larger diameter of the second housing 332 . In this way, when the part with the largest diameter of the housing 33 is disassembled, it is convenient to install and disassemble various components inside the housing 33 .

The housing 33 is provided with a micro-switch supporting part 351 , and the micro-switch supporting part 351 is detachably connected to the housing, for example, connected by bolts, screws and other connectors. In addition, the micro-switch wear support portion 351 covers the outside of the middle part of the micro-switch 35 and is detachably connected thereto. The micro-switch supporting part 351 can fix the position of the micro-switch and is easy to disassemble. The micro switch 35 is disposed inside the casing 33 . The wire 36 is electrically connected with the micro switch 35 and passes through one end of the casing 33 .

The wire 36 includes at least two wires, one is a power wire, connected to 5-12V DC; the other is a signal wire, connected to the electric control system (such as PLC) of the entire fan.

The transmission element of the micro switch 35 is in close contact with one end of the push rod 31 . The other end of the push rod 31 passes through the casing 33 and is pushed against the side of the friction disc bottom plate 11 .

The push rod 31 passes through the inside of the spring 32 and the end of the spring 32 away from the micro switch 35 is fixedly connected with the push rod 31 . The purpose of the connection between the spring 32 and the push rod 31 is to drive the push rod 31 to move when the spring 32 stretches.

The limiting portion 34 is fixedly disposed inside the housing 33 and located between the micro switch 35 and the spring 32 . The limiting portion 34 is in the shape of a circular or polygonal plate with a through hole. The shape of the limiting portion 34 depends on the internal cross-sectional shape of the housing 33 .

The push rod 31 passes through the through hole opened on the limiting part 34 , and the diameter of the through hole is smaller than the diameter of the spring 32 , and the end of the spring 32 close to the micro switch 35 is in close contact with the limiting part 34 .

The spring 32 is locked by the limiting portion 34, so the spring 32 is in a compressed state under normal conditions. Only when the friction plate is worn to a certain extent and the friction plate bottom plate 11 is separated from the push rod 31, the spring 32 just bounces off.

The transmission element of the micro switch 35 refers to the part used to trigger the micro switch on the micro switch, and common forms include push pins, buttons, levers, rollers and the like. The transmission element can transmit external force to the movable contact, so as to realize quick connection or disconnection of the movable contact and the fixed contact. Micro switch 35 is a normally closed micro travel switch.

As shown in Figure 3, after the wear sensor of the friction disc of the aircraft yaw brake is installed on the brake caliper 5, one end of the push rod 31 is pushed against the micro switch 35, and the other end is pushed against the side of the friction disc bottom plate 11, and the spring 32 is now compression.

When the friction plate is not worn to the limit, the push rod 31 is pressed against the friction plate bottom plate 11, the stroke of the micro switch 35 is compressed, the switch is in a closed state, and a normally closed signal is given.

When the friction plate wears to the limit, the bottom plate 11 of the friction plate moves outward until it breaks away from the top of the push rod 31. At this time, the push rod 31 is not blocked by the friction plate bottom plate 11, and the spring 32 pushes the push rod 31 out to make the micro switch 35 is triggered, giving a signal that the switch is open. This switch signal is connected to the PLC of the fan control system, which can be used to alarm, indicating that the friction plate has worn out to the limit and needs to be replaced. This signal can also be used to forcibly shut down the blower fan, so as to avoid accidents in which the brake disc 4 is worn out.

Claims (5)

1. a wear sensor for friction plate of fan yaw brake, is characterized in that, comprises push rod, spring, housing, limited part, microswitch and wire,

Described microswitch is arranged at described enclosure interior, and described wire is electrically connected with described microswitch and passes from shell one end;

The transmission component of described microswitch and described push rod one end close contact, the described push rod the other end passes housing;

Described push rod is fixedly connected with described push rod through described spring inner and described spring one end away from microswitch;

Described limited part is fixedly installed on described enclosure interior and between described microswitch and described spring, described push rod is through the through hole that described limited part has, and, described through-hole diameter is less than described spring diameter, and described spring is near one end of described microswitch and described limited part close contact;

Described wire at least comprises two lines, and one is power line, switches on power, and another root is signaling line, is linked in the automatical control system of whole blower fan.

2. wear sensor for friction plate of fan yaw brake according to claim 1, is characterized in that, described microswitch is Normally closed type micro limit switch.

3. wear sensor for friction plate of fan yaw brake according to claim 1 and 2, is characterized in that, described limited part is polygonal with through hole or circular plate-like shape.

4. wear sensor for friction plate of fan yaw brake according to claim 1 and 2, it is characterized in that, described housing comprises the first housing and the second housing that removably connect, and described first housing and the second housing are formed by the cylindrical or prismatic hollow tube that two sections of diameters are different

When described first housing is connected with the second housing, the hollow tube that the hollow tube that described first diameter of the housing is larger is larger with the second diameter of the housing is connected.

5. wear sensor for friction plate of fan yaw brake according to claim 1 and 2, it is characterized in that, described enclosure interior is also provided with microswitch supporting portion, described microswitch supporting portion and housing removably connect, and described microswitch perforating branches support part be coated on described microswitch in the middle part of outside and removably connect with it.