Security oil pressure interlocking steam turbine generator protection system

Abstract

The utility model discloses a security oil pressure interlocking steam turbine generator protection system, and belongs to the field of steam turbine generator technology ETS body protection. According to the structure, a security oil system is connected with a first pressure switch and a second pressure switch through a pressure guiding pipe, an automatic main steam valve closing travel switch inputs signals to an ETS protection system module through a contact of the automatic main steam valve closing travel switch in a DI mode, and the first pressure switch inputs signals to the ETS protection system module through a contact of the first pressure switch in a DI mode. The second pressure switch inputs a signal to the ETS protection system module through a contact of the second pressure switch in a DI mode, and the ETS protection system module is electrically connected with the generator circuit breaker. According to the utility model, the interlocking mechanism of the turbine and the generator can be effectively improved, and redundancy protection is increased. The automatic main steam valve closing travel switch and the security oil pressure switch are adopted to protect the system, so that the generator circuit breaker can be effectively disconnected under the emergency condition of the steam turbine, and a powerful guarantee is provided for the safe operation of the generator and the stability of an electric power system.

Description

Technical Field

[0001] The utility model relates to the field of ETS body protection of steam turbine generator technology, further relates to a steam turbine safety system oil pressure interlocking generator outlet switch tripping protection system, and specifically relates to a safety oil pressure interlocking steam turbine generator protection system. Background Art

[0002] At present, in order to ensure the safe operation of small steam turbine generator sets, in actual operation, when the automatic main steam valve of the steam turbine is closed for some reason and the steam source is lost, and the generator outlet circuit breaker does not trip, the generator changes to a motor to drive the steam turbine to rotate, absorbing a large amount of active power from the system, thereby causing fluctuations in the power system, resulting in voltage changes, and long-term operation causing grid oscillations and loss of step, causing accidents. At this time, the operating state is a reverse power operation process, and the unit can only rely on reverse power to realize the protection tripping function and implement post-event protection measures. Lack of stability and safety of pre-event control. Summary of the invention

[0003] The technical problem to be solved by the utility model is that during the operation of the steam turbine generator set, the generator fails to continuously jump to the generator due to the interruption of the steam source, resulting in reverse power operation.

[0004] In order to achieve the above technical objectives, the utility model adopts the following technical solutions:

[0005] A safety oil pressure interlocked steam turbine generator protection system comprises an automatic main steam valve closing stroke switch, a first pressure switch, a second pressure switch, an ETS protection system module, and a generator circuit breaker, wherein the safety oil system is connected to the first pressure switch and the second pressure switch via a pressure pipe, the automatic main steam valve closing stroke switch inputs a signal to the ETS protection system module via its contact point by DI, the first pressure switch inputs a signal to the ETS protection system module via its contact point by DI, the second pressure switch inputs a signal to the ETS protection system module via its contact point by DI, and the ETS protection system module is electrically connected to the generator circuit breaker.

[0006] Preferably, the pressure value of the first pressure switch and the pressure value of the second pressure switch are both 0.3 Mpa. When the pressure value is lower than the closing pressure value, the contacts are turned on.

[0007] Preferably, the specification model of the first pressure switch and the specification model of the second pressure switch are both 502-7D.

[0008] Preferably, the oil tank is connected to the automatic main steam valve through a safety oil pipeline, and a first pressure switch, a second pressure switch and a high-pressure oil pump are respectively provided on the safety oil pipeline. A bypass is connected between the safety oil pipeline and the oil tank, and an ETS solenoid valve is provided on the bypass. The automatic main steam valve is provided with an automatic main steam valve armature, and the automatic main steam valve closing stroke switch is located outside the automatic main steam valve armature.

[0009] The basic principle of this technical solution is: the safety oil system connects two 502-7D pressure switches (the first pressure switch and the second pressure switch) through a pressure pipe, and the pressure value of the first pressure switch and the second pressure switch is set to 0.3Mpa. When it is lower than the closing pressure value, the contact is turned on, and the input digital quantity DI connects the ETS module to realize the continuous tripping of the generator outlet circuit breaker. In order to ensure the accuracy of the signal, the program logic three-to-two action values ​​are adopted, that is, the automatic main steam valve closing stroke switch contact DI input, 502-7D first pressure switch and 502-7D second pressure switch contact DI input (two), and the double continuous tripping measures in advance effectively ensure the operation of small reverse power in emergencies and ensure the safe operation of the steam turbine generator.

[0010] The utility model provides a steam turbine safety system oil pressure interlock trip generator circuit breaker system, which can effectively improve the interlock mechanism between the steam turbine and the generator and increase redundant protection. The automatic main steam valve closing stroke switch and the safety oil pressure switch double interlock trip circuit breaker protection system are adopted to ensure that the generator circuit breaker can be effectively disconnected in the event of an emergency of the steam turbine, providing a strong guarantee for the safe operation of the generator and the stability of the power system.

[0011] The beneficial effects of the utility model are:

[0012] 1. The present invention adopts a double interlocking continuous tripping system to make the protection system more perfect, reduce the continuity of sudden emergency response of steam turbines and generators, and make the safety more reliable and accurate.

[0013] 2. Provides strong guarantee for the safe operation of the power grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the entity installation structure of the utility model;

[0015] Figure 2 It is a schematic diagram of the electrical connection relationship of the utility model;

[0016] In the figure:

[0017] 1. Automatic main steam valve; 2. Automatic main steam valve armature; 3. Automatic main steam valve closing stroke switch; 4. First pressure switch; 5. Second pressure switch; 6. ETS solenoid valve; 7. High-pressure oil pump; 8. Oil tank; 9. Safety oil pipeline; 10. ETS protection system module; 11. Generator circuit breaker. DETAILED DESCRIPTION

[0018] The specific implementation methods of the present invention will be described in detail below. In order to avoid too many unnecessary details, the well-known structures or functions will not be described in detail in the following examples. The approximate language used in the following examples can be used for quantitative expression, indicating that the quantity can be allowed to change without changing the basic function. Unless otherwise defined, the technical and scientific terms used in the following examples have the same meanings as those generally understood by technicians in the field to which the present invention belongs.

[0019] A safety oil pressure interlocking steam turbine generator protection system, such as Figure 1 , Figure 2 As shown, it includes an automatic main steam valve closing stroke switch 3, a first pressure switch 4, a second pressure switch 5, an ETS protection system module 10, and a generator circuit breaker 11, wherein the safety oil system is connected to the first pressure switch 4 and the second pressure switch 5 through a pressure pipe, the automatic main steam valve closing stroke switch 3 inputs a signal to the ETS protection system module 10 through its contacts in DI, the first pressure switch 4 inputs a signal to the ETS protection system module 10 through its contacts in DI, the second pressure switch 5 inputs a signal to the ETS protection system module 10 through its contacts in DI, and the ETS protection system module 10 is electrically connected to the generator circuit breaker 11. Among them, the pressure value of the first pressure switch 4 and the pressure value of the second pressure switch 5 are both 0.3Mpa, and when it is lower than the closing pressure value, the contacts are turned on. The specifications and models of the first pressure switch 4 and the second pressure switch 5 are both 502-7D. The oil tank 8 is connected to the automatic main steam valve 1 through a safety oil pipeline 9, on which a first pressure switch 4, a second pressure switch 5 and a high-pressure oil pump 7 are respectively provided, a bypass is connected between the safety oil pipeline 9 and the oil tank 8, on which an ETS solenoid valve 6 is provided, and the automatic main steam valve 1 is provided with an automatic main steam valve armature 2, and the automatic main steam valve closing stroke switch 3 is located outside the automatic main steam valve armature 2.

[0020] In the operation of a small steam turbine generator, the steam turbine continuously trips the generator through the closing of the automatic main steam valve 1, and the automatic main steam valve armature 2 touches the automatic main steam valve closing travel switch 3 to realize the continuous tripping of the generator outlet circuit breaker. In actual operation, the automatic main steam valve closing travel switch 3 is installed in the valve body of the automatic main steam valve 1. The heat transfer and heat radiation of the valve body of the automatic main steam valve 1 cause oxidation of the contacts inside the automatic main steam valve closing travel switch 3, and high-temperature deformation of the plastic part and spring part of the switch component, which is easy to lose the on-off function. This situation also occurs in actual applications, and the continuous tripping function cannot be realized. The closing function of the automatic main steam valve 1 of the steam turbine is maintained in the open state by the pressure in the safety oil system. When the oil pressure is lost, the automatic main steam valve 1 will be closed without opening pressure, so the safety oil pressure is very important in the start and stop of the system. The basic principle of this technical solution is: the safety oil system connects two 502-7D pressure switches (the first pressure switch 4 and the second pressure switch 5) through a pressure pipe, and the pressure value of the first pressure switch 4 and the second pressure switch 5 is set to 0.3Mpa. When it is lower than the closing pressure value, the contact is turned on, and the input digital quantity DI connects the ETS module to realize the continuous tripping of the generator outlet circuit breaker. In order to ensure the accuracy of the signal, the program logic three-out-of-two action value is adopted, that is, the automatic main steam valve closing stroke switch 3 contact DI input, 502-7D first pressure switch 4 and 502-7D second pressure switch 5 contact DI input (two), and the double continuous tripping measures in advance effectively ensure the operation of small reverse power in emergencies and ensure the safe operation of the steam turbine generator.

[0021] The embodiments of the present invention are described in detail above, but the contents are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the scope of application of the present invention shall be included in the protection scope of the present invention.

Claims

1. A safety oil pressure interlocking steam turbine generator protection system, characterized in that: The invention comprises an automatic main steam valve closing stroke switch (3), a first pressure switch (4), a second pressure switch (5), an ETS protection system module (10), and a generator circuit breaker (11), wherein the safety oil system is connected to the first pressure switch (4) and the second pressure switch (5) via a pressure-conducting pipe, the automatic main steam valve closing stroke switch (3) inputs a signal to the ETS protection system module (10) via its contact in the form of DI, the first pressure switch (4) inputs a signal to the ETS protection system module (10) via its contact in the form of DI, the second pressure switch (5) inputs a signal to the ETS protection system module (10) via its contact in the form of DI, and the ETS protection system module (10) is electrically connected to the generator circuit breaker (11).

2. The safety oil pressure interlocking steam turbine generator protection system according to claim 1 is characterized in that: The pressure value of the first pressure switch (4) and the pressure value of the second pressure switch (5) are both 0.3 Mpa. When the pressure value is lower than the closing pressure value, the contacts are turned on.

3. The hydraulic interlocking steam turbine generator protection system according to claim 1 is characterized in that: The specification model of the first pressure switch (4) and the specification model of the second pressure switch (5) are both 502-7D.

4. The hydraulic interlocking steam turbine generator protection system according to claim 1 is characterized in that: The oil tank (8) is connected to the automatic main steam valve (1) via a safety oil pipeline (9); a first pressure switch (4), a second pressure switch (5) and a high-pressure oil pump (7) are respectively arranged on the safety oil pipeline (9); a bypass is connected between the safety oil pipeline (9) and the oil tank (8); an ETS solenoid valve (6) is arranged on the bypass; the automatic main steam valve (1) has an automatic main steam valve armature (2); and the automatic main steam valve closing travel switch (3) is located outside the automatic main steam valve armature (2).

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