CN107014484A - A kind of Transformer Winding thrust experimental rig - Google Patents

Abstract

The invention discloses a transformer winding compression force test device, which relates to the technical field of transformer state monitoring. Aiming at the prior art, when researching the relationship between the transformer winding compression force and the vibration of the box body, a power-off hanging cover is required, and then the clip is manually adjusted. The pressing nails on the winding or the hydraulic cylinder are used to adjust the pressing force of the winding, resulting in unreliable fastening and spending a lot of time, manpower, material and financial resources. At the same time, it increases the technical problem of the risk of the transformer being damp. The use of hydraulic cylinders, vibration sensors , high-pressure oil pipe and electric oil pump, the hydraulic oil cylinder is between the clamp and the pressure plate, the vibration sensor is fixed on the outer surface of the transformer box, and the electric oil pump exerts pressure on the hydraulic oil cylinder through the high-pressure oil pipe. The present invention is ingenious in design, reasonable in layout, low in cost and easy to use , it can continuously and accurately adjust the compression force of the transformer winding in operation without the suspension cover and oil discharge, and it is convenient to carry out the research on the transformer compression force-vibration characteristics intuitively.

Description

A device for testing the compression force of transformer windings

technical field

The invention relates to the technical field of transformer state monitoring, in particular to a transformer winding compression force test device.

Background technique

Power transformers are one of the most important equipment in power plants and substations, and their safety has an important impact on power grids and social stability. When a short-circuit accident occurs in the transformer, the axial force on the winding is very large. However, the winding itself does not have the ability to withstand axial force, and it is guaranteed by external force (clamping force and axial pressing force of the clamp). If the pressing force decreases, the winding becomes loose, and its short-circuit strength cannot be guaranteed. Therefore, it is very important to know the axial compression force of the winding in time, and the compression force of the winding can be reflected by the vibration of the box during the operation of the transformer.

At present, the research on the relationship between the compacting force of the transformer winding and the vibration of the box body is carried out after the power failure hood, or by manually adjusting the pressing nail on the clamp, or adjusting the compressing force of the winding through the hydraulic cylinder. For the former, every The pressing force of a phase winding is generally tens of tons, and it is not reliable to tighten it with a wrench by manpower alone. First, the manpower is limited, and the output cannot meet the requirements; The thread fit is tight, even though it took a lot of effort to tighten the screw manually, the screw actually did not compress the body winding. For the latter, after the hydraulic cylinder is adjusted, the screw on the clamp also needs to be manually adjusted, resulting in The compression force falls back. Moreover, both of these two methods require adjustment after a power outage, which not only cannot achieve continuous adjustment, but also consumes a lot of time, manpower, material and financial resources, and increases the risk of the transformer being damp.

Contents of the invention

The invention provides a transformer winding compression force test device, which is used to solve the problem of the prior art when conducting research on the relationship between the transformer winding compression force and the box vibration. Pressing nails or adjusting the pressing force of windings through hydraulic cylinders results in unreliable fastening and consumes a lot of time, manpower, material and financial resources, and at the same time increases the technical problem of the risk of moisture in the transformer.

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

A transformer winding compression force test device, including a hydraulic cylinder, a vibration sensor, a high-pressure oil pipe and an electric oil pump, the hydraulic cylinder is installed on the clamp of the transformer, and the installation plane of the hydraulic cylinder is parallel to the plane of the pressure plate of the transformer with an interval of 60 degrees distribution, the vibration sensor is installed on the outer wall of the transformer box, the high-voltage oil pipe is arranged inside the transformer box, the hydraulic cylinder is connected to the oil injection/drain valve of the transformer through the high-pressure oil pipe, and the electric oil pump is arranged on the transformer Outside the box body, the electric oil pump is connected with the oil filling/draining valve.

Preferably, the hydraulic cylinder includes a cylinder body and a piston rod, the cylinder body is installed upside down on the clip, and the top of the piston rod points to the pressure plate.

Preferably, the hydraulic oil cylinder has a maximum working pressure of 14MPa and a stroke of 30mm.

Preferably, the vibration sensor is an acceleration sensor with a frequency of 0-1500 Hz.

Preferably, the high-pressure oil pipe is made of polytetrafluoroethylene for connecting the cylinder body and the oil injection/drain valve, and the high-pressure oil pipe is fixed on the clamp.

Preferably, the electric oil pump includes a motor, an oil pump, a solenoid valve, a pressure gauge, a controller and an oil tank, the motor is connected to the oil pump, the oil inlet of the oil pump is connected to the oil tank, and the oil outlet of the oil pump is connected to the solenoid valve , the solenoid valve is connected to the pressure gauge, and the pressure gauge is connected to the oil injection/drainage valve; the motor is used to drive the oil pump to make the hydraulic oil in the oil tank pass through the oil pump, electromagnetic valve, pressure gauge, injection/drainage valve and high-pressure oil pipe to the hydraulic cylinder. Oil supply or oil suction, so that the top of the piston rod is close to or away from the pressure plate, the solenoid valve is used to cut off or open the pipeline of the high-pressure oil pipe, the pressure gauge is a digital pressure gauge, used to display the actual pressure value of the high-pressure oil pipe, the controller is connected The pressure gauge, motor and solenoid valve are used to set the target pressure value in the high-pressure oil pipe, and after comparing with the actual pressure value of the pressure gauge, control the start and stop, forward and reverse rotation of the motor and the opening and closing of the solenoid valve to make the pressure gauge The actual pressure value is equal to the target pressure value set in the controller.

Compared with prior art, the beneficial effect of the present invention is:

1. The present invention has ingenious design, reasonable layout, low cost and convenient use;

2. It can continuously and accurately adjust the pressing force of the transformer winding in operation without the suspension cover and oil discharge;

3. It is convenient and intuitive to carry out the research on the compression force-vibration characteristics of transformers.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings that need to be used in the description of the embodiments.

Fig. 1 is a structural representation of the present invention;

Figure 2 is a side view of the winding and the core;

Figure 3 is a top view of the winding and the core.

Among them, the marks shown in the figure are: 1: Transformer box; 2: Winding; 3: Pressure plate; 4: Iron core; 5: Bushing; 6: Hydraulic cylinder; 7: Clamp; 8: Vibration sensor; 9: High-pressure oil pipe; 10: electric oil pump; 11: upper box; 12: lower box; 13: injection/drain valve; 14: air release valve; 21: high-voltage winding; 22: low-voltage winding; 51: high-voltage sleeve Tube; 52: low pressure bushing; 61: cylinder body; 62: piston rod; 101: electric motor; 102: oil pump; 103: solenoid valve; 104: pressure gauge; 105: controller; 106: oil tank.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Apparently, the described embodiments are only some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the term "inner" is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship that is usually placed when the product of the invention is used , is only for the convenience of describing the present invention and simplifying the description, but does not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention.

In the description of the present invention, it should also be noted that, unless otherwise clearly specified and limited, the terms "setting", "connection" and the like should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection, Or integrally connected; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary, and it may be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

Please refer to Figure 1, Figure 2 and Figure 3, a transformer winding compression test device, including transformer box 1, winding 2, pressure plate 3, iron core 4, bushing 5, hydraulic cylinder 6, clamp 7 and vibration sensor8. The transformer box 1 includes an upper section box body 11 , a lower section box body 12 , an oil injection/drain valve 13 and an air release valve 14 . The winding 2 is set on the iron core 4. The iron core 4 is made of laminated silicon steel sheets of 0.35-0.5 mm, and is bound and compressed by a through-hole screw or a drawstring. The winding 2 includes a high-voltage winding 21 and a low-voltage winding 22. The low-voltage winding 22 Close to the iron core 4, the high-voltage winding 21 is on the outer layer of the low-voltage winding 22, the pressure plate 3 is arranged on the top of the winding 2, the pressure plate 3 is a circular electrical laminated wood board, the clip 7 is installed on both sides of the iron core 4, and the hydraulic cylinder 6 The maximum working pressure is 14MPa, the stroke is 30mm, and it is installed on the clamp 7 at an interval of 60 degrees, and the installation plane is parallel to the plane of the pressure plate. The hydraulic cylinder 6 includes a cylinder 61 and a piston rod 62. The cylinder 61 is installed on the clamp 7 upside down. Above, the top of the piston rod 62 points to the pressure plate 3, the high-pressure oil pipe 9 is made of polytetrafluoroethylene, fixed along the clip 7, and connected to the cylinder 61 and the oil injection/drain valve 13, and the iron core 4 is installed in the transformer box 1 bottom, that is, the bottom of the lower box 12, the upper box 11 and the lower box 12 are sealed and connected by bolts and rubber pads, the bushing 5 is installed outside the transformer box 1, and the bushing 5 includes a high-voltage bushing 51 and The low-voltage bushing 52, the high-voltage bushing 51 is connected to the high-voltage winding 21, the low-voltage bushing 52 is connected to the low-voltage winding 22, and the transformer oil is injected through the injection/drain valve 13 fixed at the bottom of the transformer box 1 until the entire The transformer box 1 is filled with oil while releasing air through the air release valve 14. The vibration sensor 8 is installed on the outer wall of the transformer box 1. The vibration sensor 8 is an acceleration sensor with a frequency of 0-1500 Hz.

The electric oil pump 10 is outside the transformer box body 1, and includes a motor 101, an oil pump 102, a solenoid valve 103, a pressure gauge 104, a controller 105, and an oil tank 106. The motor 101 is connected to the oil pump 102, and the oil inlet of the oil pump 102 is connected to the oil tank 106 Connection, the oil outlet of the oil pump 102 is connected with the solenoid valve 103, the solenoid valve 103 is connected with the pressure gauge 104, and the pressure gauge 104 is connected with the injection/drain valve 13. The motor 101 is used to drive the oil pump 102 to make the hydraulic oil in the oil tank 106 supply or absorb oil to the hydraulic cylinder 6 through the oil pump 102, electromagnetic valve 103, pressure gauge 104, injection/drain valve 13 and high-pressure oil pipe 9, so as to realize the piston rod. The top of 62 is close to or away from the pressure plate 3, the solenoid valve 103 is used to cut off or open the pipeline of the high-pressure oil pipe 9, the pressure gauge 104 is a digital pressure gauge, and is used to display the actual pressure value of the high-pressure oil pipe 9, and the controller 105 is connected to the pressure gauge 104. The motor 101 and the solenoid valve 103 are used to set the target pressure value in the high-pressure oil pipe 9 and compare it with the actual pressure value of the pressure gauge 104 to control the start and stop, forward and reverse rotation of the motor 101 and the opening and closing of the solenoid valve 103 , so that the actual pressure value of the pressure gauge 104 is equal to the target pressure value set in the controller 105 .

When carrying out the vibration test, first set the target pressure value in the controller 105, if the target pressure value is less than the actual pressure value of the pressure gauge 104, the controller 105 controls the electromagnetic valve 103 to open, then connects the power supply of the motor 101 and controls its forward rotation At this time, the motor 101 drives the oil pump 102 to suck the hydraulic oil in the oil tank 106 and transport it to the cylinder body 61 of the hydraulic cylinder 6 through the high-pressure oil pipe 9, and then push the piston rod 62 to move toward the pressure plate 3, and push the pressure plate 3 to When the actual pressure value of the pressure gauge 104 reaches the target pressure value, the controller 105 controls the solenoid valve 103 to close and cut off the power supply of the motor 101, so that the piston rod 62 is stationary. A voltage is applied to the bushing 5 , and the vibration acceleration value of the transformer box 1 corresponding to the target pressure value can be observed through the vibration sensor 8 .

If the target pressure value is greater than the actual pressure value of the pressure gauge 104, the controller 105 controls the solenoid valve 103 to open, and turns on the power of the motor 101 and controls its reverse rotation. At this time, the motor 101 drives the oil pump 102 to transfer the hydraulic oil in the hydraulic cylinder 6 through The high-pressure oil pipe 9 is sucked into the oil tank 106. At this time, the piston rod 62 contracts and moves away from the pressure plate 3 until the actual pressure value of the pressure gauge 104 is equal to the target pressure value. The controller 105 controls the solenoid valve 103 to close and cut off the power supply of the motor 101, thereby Realize that the piston rod 62 is static. A voltage is applied to the bushing 5 , and the vibration acceleration value of the transformer box 1 corresponding to the target pressure value can be observed through the vibration sensor 8 .

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. All should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (6)

1. a kind of Transformer Winding thrust experimental rig, including hydraulic jack（6）, vibrating sensor（8）, high-pressure oil pipe（9） And electric oil pump（10）, it is characterised in that：The hydraulic jack（6）Installed in the folder of transformer（7）Above, hydraulic jack （6）Mounting plane and transformer pressing plate（3）Plane is parallel and 60 degree of interval is distributed, the vibrating sensor（8）It is arranged on Transformer-cabinet（1）Outer wall, the high-pressure oil pipe（9）It is arranged on transformer-cabinet（1）Inside, the hydraulic jack（6）Pass through The high-pressure oil pipe（9）With note/oil discharging valve of transformer（13）Connection, the electric oil pump（10）It is arranged on transformer-cabinet （1）Outside, electric oil pump（10）With note/oil discharging valve（13）Connection.

2. device according to claim 1, it is characterised in that：The hydraulic jack（6）Including cylinder body（61）And piston rod （62）, the cylinder body（61）Inversion is installed in the folder（7）Above, the piston rod（62）Top point to the pressing plate （3）.

3. device according to claim 2, it is characterised in that：The hydraulic jack（6）Maximum working pressure (MWP) be 14MPa, stroke is 30mm.

4. device according to claim 1, it is characterised in that：The vibrating sensor（8）It is frequency 0 ~ 1500Hz's Acceleration transducer.

5. device according to claim 1, it is characterised in that：The high-pressure oil pipe（9）It is made up, is used for of polytetrafluoroethylene (PTFE) Connect the cylinder body（61）And note/the oil discharging valve（13）, the high-pressure oil pipe（9）It is fixed on the folder（7）On.

6. device according to claim 11, it is characterised in that：The electric oil pump（10）Including motor（101）, oil Pump（102）, magnetic valve（103）, pressure gauge（104）, controller（105）And oil tank（106）, the motor（101）With oil pump （102）Connection, oil pump（102）Oil inlet and oil tank（106）Connection, oil pump（102）Oil-out and magnetic valve（103）Even Connect, magnetic valve（103）With pressure gauge（104）Connection, pressure gauge（104）With note/oil discharging valve（13）Connection；Motor（101） For driving oil pump（102）Make oil tank（106）In hydraulic oil pass through oil pump（102）, magnetic valve（103）, pressure gauge（104）、 Note/oil discharging valve（13）And high-pressure oil pipe（9）To hydraulic jack（6）Fuel feeding or oil suction, so as to realize piston rod（62）Top Closer or far from pressing plate（3）, magnetic valve（103）For cutting off or opening high-pressure oil pipe（9）Pipeline, pressure gauge（104）For number Word formula pressure gauge, for showing high-pressure oil pipe（9）Actual pressure value, controller（105）Connect pressure gauge（104）, motor （101）And magnetic valve（103）, for setting high-pressure oil pipe（9）In target pressure value, and and pressure gauge（104）Actual pressure Force value relatively after, control motor（101）Start and stop and rotating and magnetic valve（103）Opening and closing, make pressure gauge（104）'s Actual pressure value is equal to controller（105）The target pressure value of middle setting.