Discharge ablation fault detection device for damping bar of rotor of tubular hydraulic generator

Abstract

The utility model discloses a discharge ablation fault detection device for a damping bar of a rotor of a tubular hydraulic generator. The discharge ablation fault detection device comprises an ozone sensor, an amplification filter circuit and an A / D converter which are connected in sequence, wherein the ozone sensor is installed at a position, close to an air gap, of a ventilation duct of a stator slot of the tubular hydro-generator; and the A / D converter is connected with the upper computer. According to the utility model, whether the damping bar is healthy or not is detected by detecting ozone gas generated along with discharge when the damping bar has an ablation fault, and timely early warning can be carried out on discharge ablation and even overheat fracture faults of the damping bar. According to the utility model, the ozone sensor is installed at the position of the stator side ventilation duct close to the air gap, and other circuit wires are all located outside the generator casing, so that normal operation of the detection circuit is ensured, normal operation of the generator is not affected, and generation of ozone can be accurately and rapidly detected.

Description

Technical Field

[0001] The utility model relates to the technical field of safety detection of tubular turbine generators, in particular to a discharge ablation fault detection device for rotor damping strips of tubular turbine generators. Background Art

[0002] For large hydro-turbine generators, damping strips not only help stabilize their synchronous speed, but also weaken the impact of overvoltage and suppress oscillation during motor operation. They are important components to ensure the safe and stable operation of hydro-turbine generators.

[0003] The tubular turbine generator is the preferred unit for developing low-head, large-capacity hydropower resources and tidal resources. However, in recent years, with the increase in the capacity of such generators, many such units at home and abroad have experienced overheating, ablation and even broken damping bars, which has caused great damage to the safe and stable operation of the generator and the power grid. In order to prevent the above-mentioned failures, it is necessary to monitor the operating status of the generator damping bars in a timely manner to prevent serious ablation or even broken damping bars.

[0004] The detection methods for the discharge ablation fault of the damping strip of large-scale tubular turbine generators usually adopt electrical maintenance, infrared imaging detection, etc. However, they often have certain limitations, such as shutdown maintenance will affect the power supply, and non-direct contact detection will have the disadvantages of large measurement errors and long delay time. Utility Model Content

[0005] In view of the above-mentioned deficiencies in the prior art, the utility model provides a discharge ablation fault detection device for the rotor damping strip of a tubular turbine generator, which solves the problems that shutdown for maintenance will affect the power supply and non-direct contact detection will have large measurement errors and long delay times.

[0006] In order to achieve the above-mentioned purpose of the invention, the technical solution adopted by the utility model is:

[0007] Provided is a device for detecting discharge ablation fault of a rotor damping strip of a tubular turbine generator, comprising an ozone sensor, an amplifying filter circuit and an A / D converter connected in sequence; wherein the ozone sensor is installed near the air gap of a stator slot ventilation groove of the tubular turbine generator; and the A / D converter is connected to a host computer.

[0008] Further, the model of the ozone sensor is OX-B431.

[0009] Furthermore, the amplifying and filtering circuit includes a chip U1 of model ADA4530-1, a chip U2 of model MAX297, and a chip U3 of model AD8630; the inverting input terminal of the chip U1 is respectively connected to one end of the resistor R5 and one end of the capacitor C5, and serves as the input terminal of the amplifying and filtering circuit; the inverting input terminal of the chip U1 is grounded; the output terminal of the chip U1 is respectively connected to the other end of the resistor R5, the other end of the capacitor C5, and the input terminal of the chip U2;

[0010] The CLK pin of chip U2 is connected to the grounded capacitor C1; the positive power connection end of chip U2 is respectively connected to one end of resistor R1, one end of capacitor C3 and the positive pole of the external power supply; the other end of resistor R1 is respectively connected to the ground pin of chip U2, one end of resistor R2 and one end of capacitor C2; the other end of resistor R2, the other end of capacitor C2, the other end of capacitor C3 and the negative power connection end of chip U2 are all grounded; the output end of chip U2 is respectively connected to the grounded capacitor C4 and the in-phase input end of chip U3;

[0011] The inverting input terminal of the chip U3 is connected to the grounding resistor R4 and one end of the resistor R3 respectively; the output terminal of the chip U3 is connected to the other end of the resistor R3 and serves as the output terminal of the amplifying and filtering circuit.

[0012] Furthermore, the model of the A / D converter is AD7195.

[0013] Furthermore, the A / D converter is connected to the host computer via an RS485 communication cable.

[0014] The beneficial effects of the utility model are:

[0015] 1. The utility model detects whether the damping strip is healthy by detecting the ozone gas generated by discharge when the damping strip has ablation failure, and can provide timely warning for discharge ablation and even overheating and fracture failure of the damping strip.

[0016] 2. The utility model installs the ozone sensor on the ventilation groove on the stator side close to the air gap, and the remaining circuit wiring is located outside the generator casing. While ensuring the normal operation of the detection circuit itself, it does not cause any impact on the normal operation of the generator, and can also accurately and quickly detect the generation of ozone. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is the structural principle diagram of the device;

[0018] Figure 2 This is a cutaway diagram of the installation of the ozone sensor;

[0019] Figure 3 This is the installation side view of the ozone sensor;

[0020] Figure 4This is the circuit diagram of the amplifier filter circuit. DETAILED DESCRIPTION

[0021] The specific implementation modes of the present invention are described below to facilitate the understanding of the present invention by those skilled in the art. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0022] like Figure 1 , Figure 2 and Figure 3 As shown, the discharge ablation fault detection device for the rotor damping strip of the tubular turbine generator comprises an ozone sensor, an amplifying filter circuit and an A / D converter which are connected in sequence; wherein the ozone sensor is installed near the air gap of the stator slot ventilation groove of the tubular turbine generator; and the A / D converter is connected to the host computer.

[0023] In this embodiment, the model of the ozone sensor is OX-B431. The model of the A / D converter is AD7195. The A / D converter is connected to the host computer via an RS485 communication cable.

[0024] like Figure 4 As shown, the amplifying and filtering circuit includes a chip U1 of model ADA4530-1, a chip U2 of model MAX297, and a chip U3 of model AD8630; the inverting input terminal of the chip U1 is respectively connected to one end of the resistor R5 and one end of the capacitor C5, and serves as the input terminal of the amplifying and filtering circuit; the inverting input terminal of the chip U1 is grounded; the output terminal of the chip U1 is respectively connected to the other end of the resistor R5, the other end of the capacitor C5, and the input terminal of the chip U2;

[0025] The CLK pin of chip U2 is connected to the grounded capacitor C1; the positive power connection end of chip U2 is respectively connected to one end of resistor R1, one end of capacitor C3 and the positive pole of the external power supply; the other end of resistor R1 is respectively connected to the ground pin of chip U2, one end of resistor R2 and one end of capacitor C2; the other end of resistor R2, the other end of capacitor C2, the other end of capacitor C3 and the negative power connection end of chip U2 are all grounded; the output end of chip U2 is respectively connected to the grounded capacitor C4 and the in-phase input end of chip U3;

[0026] The inverting input terminal of the chip U3 is connected to the grounding resistor R4 and one end of the resistor R3 respectively; the output terminal of the chip U3 is connected to the other end of the resistor R3 and serves as the output terminal of the amplifying and filtering circuit.

[0027] In one embodiment of the utility model, the ablation failure of the damping strip is often accompanied by discharge. During the corona discharge process, plasma will be generated in the air gap area near the damping strip, and a series of gas decomposition products such as ozone will be obtained. Therefore, the device can judge the health status of the rotor damping strip by collecting, detecting, and judging the air gap ozone concentration in the area near the damping strip, and then timely warn of the discharge ablation and even overheating fracture failure of the damping strip.

[0028] In the specific implementation process, the circuit part of the device other than the ozone sensor can be distributed outside the generator casing, and can communicate directly with the host computer in real time through the RS485 communication cable. The host computer can be used to display ozone concentration information, and send out an alarm or shutdown signal according to the ozone concentration information, so as to prevent the damping bar from further deteriorating in time, so as to avoid more serious accidents such as broken bars, and prevent greater economic losses.

[0029] In summary, the utility model can avoid the shortcomings of traditional electrical detection, such as the need to interrupt power supply and large measurement errors and long delay times in infrared imaging detection results. It can detect the health status of the damping strip under any working conditions with high accuracy and can effectively prevent the breakage of the damping strip.

Claims

1. A device for detecting the discharge and ablation fault of the rotor damping strip of a tubular turbine generator, characterized in that: It includes an ozone sensor, an amplifying and filtering circuit and an A / D converter connected in sequence; The ozone sensor is installed in the ventilation groove of the stator slot of the tubular turbine generator close to the air gap; the A / D converter is connected to the host computer.

2. A device for detecting discharge ablation faults of rotor damping strips of a tubular turbine generator according to claim 1, characterized in that: The model of the ozone sensor is OX-B431.

3. The device for detecting the discharge and ablation fault of the rotor damping strip of a tubular turbine generator according to claim 1, characterized in that: The amplifying and filtering circuit includes a chip U1 of model ADA4530-1, a chip U2 of model MAX297, and a chip U3 of model AD8630; the inverting input terminal of the chip U1 is respectively connected to one end of the resistor R5 and one end of the capacitor C5, and serves as the input terminal of the amplifying and filtering circuit; the inverting input terminal of the chip U1 is grounded; the output terminal of the chip U1 is respectively connected to the other end of the resistor R5, the other end of the capacitor C5, and the input terminal of the chip U2; The CLK pin of chip U2 is connected to the grounded capacitor C1; the positive power connection end of chip U2 is respectively connected to one end of resistor R1, one end of capacitor C3 and the positive pole of the external power supply; the other end of resistor R1 is respectively connected to the ground pin of chip U2, one end of resistor R2 and one end of capacitor C2; the other end of resistor R2, the other end of capacitor C2, the other end of capacitor C3 and the negative power connection end of chip U2 are all grounded; the output end of chip U2 is respectively connected to the grounded capacitor C4 and the in-phase input end of chip U3; The inverting input terminal of the chip U3 is connected to the grounding resistor R4 and one end of the resistor R3 respectively; the output terminal of the chip U3 is connected to the other end of the resistor R3 and serves as the output terminal of the amplifying and filtering circuit.

4. A device for detecting discharge ablation faults of rotor damping bars of a tubular turbine generator according to claim 1, characterized in that: The model of A / D converter is AD7195.

5. A device for detecting discharge ablation faults of rotor damping bars of a tubular turbine generator according to claim 4, characterized in that: The A / D converter is connected to the host computer via an RS485 communication cable.

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