Wiring structure for connecting small power generator matched with back pressure extraction type steam turbine to auxiliary power supply
By designing the wiring structure of the small generator connection system with back pressure pumping turbine, the wiring problem of the inconvenient connection between the converter system and the 10kV switch cabinet during the small generator is solved, and the reliable connection of the system is achieved and control improves the stability and security of the overall system.
Patent Information
- Application Number
- CN202420208514.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-29
- Publication Date
- 2025-02-11
- Estimated Expiration
- 2034-01-29
AI Technical Summary
In the prior art, when the small generator is connected to the factory power system, there is a lack of an effective wiring structure to connect the converter system with the 10kV switch cabinet, resulting in insufficient control and protection measures.
A wiring structure for back pressure pumping steam turbine connected to the factory power system is designed, including small generator, converter system and 10kV switch cabinet. Through specific wiring methods and locking measures, the change is ensured. Reliable connection and control of the flow device system with 10kV switch cabinet.
It realizes stable access between small generators and factory power systems, ensures the wiring, control, protection and locking interface requirements between the converter system and the 10kV switch cabinet, and improves the reliable connection between the thermal system and the electrical system.
Smart Images
Figure CN222463790U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of installation and wiring, and more specifically to a wiring structure for connecting a small generator matched with a back-pressure extraction steam turbine to a plant power system. Background Art
[0002] The BEST small unit is equipped with a balanced motor to keep the steam inlet valve of the small turbine fully open within a larger main engine load range, avoid throttling losses, improve the unit efficiency under partial load, and achieve flexible operation of steam-electric dual drive.
[0003] At present, the high-voltage switch, converter, and phase-shifting rectifier connected to the small generator are all part of the complete set of converter system configurations, and reliable technologies have been verified in practice in China. The protection and control of the small generator and its excitation system, converter, and phase-shifting rectifier are all implemented within the scope of the converter system.
[0004] Therefore, it is necessary to develop a wiring structure for connecting a converter system connected to a small generator and a 10kV switch cabinet. Utility Model Content
[0005] The purpose of the utility model is to overcome the shortcomings of the above-mentioned background technology and to provide a wiring structure for connecting a small generator supporting a back-pressure extraction steam turbine to a plant power system.
[0006] In order to achieve the above-mentioned purpose, the technical solution of the utility model is: a wiring structure for connecting a small generator of a back-pressure extraction steam turbine to the power supply of a factory, characterized in that it includes a small generator, a converter system and a 10kV switch cabinet, wherein the converter system includes a high-voltage switch connected to the small generator, a converter connected to the high-voltage switch, and a phase-shifting rectifier connected to the converter;
[0007] The 10kV switch cabinet has a 10kV working section A bus and a 10kV working section B bus. The 10kV working section A bus is connected to the phase-shifting rectifier transformer through a first incoming line, and the 10kV working section B bus is connected to the phase-shifting rectifier transformer through a second incoming line.
[0008] The phase-shifting rectifier transformer is connected to the 10kV working section A busbar through the first incoming line and the first switch in sequence, and the ground switch is connected to the first incoming line;
[0009] The phase-shifting rectifier transformer is connected to the 10kV working section B busbar through the second incoming line and the second switch in sequence;
[0010] The switch quantity signals of the ground switch, the first switch and the second switch are all sent to the converter control cabinet in the form of passive dry contacts.
[0011] In the above technical solution, the first switch and the second switch both receive the emergency trip command of the converter control cabinet, the phase-shift rectifier transformer protection action trip command, and the small generator protection action trip command.
[0012] In the above technical solution, the first switch and the second switch are locked by hard wiring, and the first switch and the second switch are prohibited from being closed at the same time; the earth knife and the first switch are mechanically locked, and the earth knife and the first switch are prohibited from being closed at the same time; the earth knife and the second switch are locked by hard wiring, and the earth knife and the second switch are prohibited from being closed at the same time; the earth knife and the converter control cabinet are locked by hard wiring, and the converter control cabinet is prohibited from closing the first switch and the second switch when the earth knife is in the closed position.
[0013] In the above technical solution, the voltage of the 10kV working section A bus is sent to the converter control cabinet through the first bus voltage transformer, and the voltage of the 10kV working section B bus is sent to the converter control cabinet through the second bus voltage transformer.
[0014] In the above technical solution, the current of the first incoming switch cabinet is sent to the converter control cabinet through the first current transformer; the current of the second incoming switch cabinet is sent to the converter control cabinet through the second current transformer.
[0015] In the above technical solution, the first incoming line is connected to the first line comprehensive protection and measurement and control device through a third current transformer, and the third current transformer is located between the first current transformer and the first switch;
[0016] The second incoming line is connected to the second line comprehensive protection and measurement and control device through a fourth current transformer, and the fourth current transformer is located between the second current transformer and the second switch.
[0017] In the above technical solution, the first incoming line is connected to the first line comprehensive protection and measurement and control device through the fifth current transformer, and the fifth current transformer is located between the first current transformer and the third current transformer; the second incoming line is connected to the second line comprehensive protection and measurement and control device through the sixth current transformer, and the sixth current transformer is located between the second current transformer and the fourth current transformer.
[0018] In the above technical solution, the first incoming line is connected to the first watt-hour meter through the seventh current transformer, and the seventh current transformer is located between the first current transformer and the fifth current transformer;
[0019] The second incoming line is connected to the second watt-hour meter through an eighth current transformer, and the eighth current transformer is located between the second current transformer and the sixth current transformer.
[0020] In the above technical solution, the first incoming line is connected to the first line comprehensive protection and measurement and control device through a first zero-sequence current transformer, and the first zero-sequence current transformer is located between the first current transformer and the phase-shifting rectifier;
[0021] The second incoming line is connected to the second line comprehensive protection and measurement and control device through a second zero-sequence current transformer, and the second zero-sequence current transformer is located between the second current transformer and the phase-shifting rectifier; the grounding switch is connected between the first current transformer and the first zero-sequence current transformer.
[0022] In the above technical solution, the 10kV switch cabinet is equipped with an arc protection device, and the arc protection action of the arc protection device trips the 10kV bus section main power supply incoming line switch while simultaneously tripping the first switch and the second switch.
[0023] Compared with the prior art, the utility model has the following advantages:
[0024] 1) Through the utility model, a small generator is connected to the plant power system, and the wiring, control, protection and locking interface requirements of the converter system and the 10kV switch cabinet are realized, ensuring the reliable connection between the thermal system and the electrical system. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] Figure 1 It is a structural schematic diagram of the utility model.
[0026] Among them, 1- small machine generator, 2- converter system, 21- high voltage switch, 22- converter, 23- phase shift rectifier, 3- 10kV switch cabinet, 31- 10kV working section A bus, 311- first incoming line, 312- ground switch, 313- first switch, 32- 10kV working section B bus, 321- second incoming line, 33- arc protection device, 331- arc sensor, 332- arc control unit, 41- first bus voltage transformer, 42- second bus voltage transformer voltage transformer, 51-first line integrated protection and measurement and control device, 52-second line integrated protection and measurement and control device, 53-first electric meter, 54-second electric meter, 61-first current transformer, 62-second current transformer, 63-third current transformer, 64-fourth current transformer, 65-fifth current transformer, 66-sixth current transformer, 67-seventh current transformer, 68-eighth current transformer, 71-first zero-sequence current transformer, 72-second zero-sequence current transformer. DETAILED DESCRIPTION
[0027] The following is a detailed description of the implementation of the utility model in conjunction with the accompanying drawings, but they do not constitute a limitation of the utility model and are only used as examples. At the same time, the advantages of the utility model will become clearer and easier to understand through the description.
[0028] Referring to the attached drawings, it can be seen that the wiring structure of the small generator supporting the back-pressure extraction steam turbine connected to the factory power supply is characterized by comprising a small generator 1, a converter system 2 and a 10kV switch cabinet 3, wherein the converter system 2 comprises a high-voltage switch 21 connected to the small generator 1, a converter 22 connected to the high-voltage switch 21, and a phase-shifting rectifier 23 connected to the converter 22;
[0029] The 10kV switch cabinet 3 has a 10kV working section A bus 31 and a 10kV working section B bus 32. The 10kV working section A bus 31 is connected to the phase-shifting rectifier transformer 23 via a first incoming line 311, and the 10kV working section B bus 32 is connected to the phase-shifting rectifier transformer 23 via a second incoming line 321.
[0030] The phase-shifting rectifier transformer 23 is connected to the 10kV working section A bus 31 through the first incoming line 311 and the first switch 313 in sequence, and the ground switch 312 is connected to the first incoming line 311;
[0031] The phase-shifting rectifier transformer 23 is connected to the 10kV working section B bus 32 through the second incoming line 321 and the second switch 322 in sequence;
[0032] The switch signals of the ground switch 312, the first switch 313 and the second switch 322 are all sent to the control cabinet of the converter 22 in the form of passive dry contacts;
[0033] When the unit is in startup condition, the operating personnel can determine by themselves whether to control the small generator 1 to run in motor state from the 10kV working section A bus 31 or the 10kV working section B bus 32 through the control cabinet matching the converter 22 to drive the water supply pump.
[0034] When the unit is in normal operating condition, the surplus shaft power of the back-pressure extraction steam turbine driving the feed water pump is used to generate electricity through the small generator 1; the small generator 1 is connected to the plant power system through the 10kV working section A bus 31 or the 10kV working section B bus 32 specified during the startup condition.
[0035] The first switch 313 and the second switch 322 both receive the emergency trip command of the converter 22 control cabinet, the protection action trip command of the phase-shifting rectifier 23, and the protection action trip command of the small generator 1; and the following locking requirements must be met:
[0036] The first switch 313 and the second switch 322 are locked by hard wiring, and the first switch 313 and the second switch 322 are prohibited from being closed at the same time; the earth knife 312 and the first switch 313 are mechanically locked, and the earth knife 312 and the first switch 313 are prohibited from being closed at the same time; the earth knife 312 and the second switch 322 are locked by hard wiring, and the earth knife 312 and the second switch 322 are prohibited from being closed at the same time; the earth knife 312 and the converter 22 control cabinet are locked by hard wiring, and when the earth knife 312 is in the closed position, the converter 22 control cabinet is prohibited from closing the first switch 313 and the second switch 322.
[0037] The voltage of the 10kV working section A bus 31 is sent to the converter 22 control cabinet through the first bus voltage transformer 41 , and the voltage of the 10kV working section B bus 32 is sent to the converter 22 control cabinet through the second bus voltage transformer 42 .
[0038] The switch cabinet current of the first incoming line 311 is sent to the converter 22 control cabinet through the first current transformer 61 ; the switch cabinet current of the second incoming line 321 is sent to the converter 22 control cabinet through the second current transformer 62 .
[0039] The first incoming line 311 is connected to the first line integrated protection and measurement and control device 51 through the third current transformer 63, and the third current transformer 63 is located between the first current transformer 61 and the first switch 313;
[0040] The second incoming line 321 is connected to the second line integrated protection and measurement and control device 52 through a fourth current transformer 64 , and the fourth current transformer 64 is located between the second current transformer 62 and the second switch 322 .
[0041] The first incoming line 311 is connected to the first line integrated protection and measurement control device 51 through the fifth current transformer 65, and the fifth current transformer 65 is located between the first current transformer 61 and the third current transformer 63; the second incoming line 321 is connected to the second line integrated protection and measurement control device 52 through the sixth current transformer 66, and the sixth current transformer 66 is located between the second current transformer 62 and the fourth current transformer 64; the measurement function of the 10kV switch cabinet 3 is realized;
[0042] The first incoming line 311 is connected to the first electric meter 53 through the seventh current transformer 67, and the seventh current transformer 67 is located between the first current transformer 61 and the fifth current transformer 65; the second incoming line 321 is connected to the second electric meter 54 through the eighth current transformer 68, and the eighth current transformer 68 is located between the second current transformer 62 and the sixth current transformer 66; the metering function of the 10kV switch cabinet is realized.
[0043] The first incoming line 311 is connected to the first line comprehensive protection and measurement and control device 51 through the first zero-sequence current transformer 71, and the first zero-sequence current transformer 71 is located between the first current transformer 61 and the phase-shifting rectifier 23;
[0044] The second incoming line 321 is connected to the second line comprehensive protection and measurement and control device 52 through the second zero-sequence current transformer 72, and the second zero-sequence current transformer 72 is located between the second current transformer 62 and the phase-shifting rectifier 23; the grounding knife 312 is connected between the first current transformer 61 and the first zero-sequence current transformer 71.
[0045] The 10kV switch cabinet 3 is equipped with an arc protection device 33. The arc protection action of the arc protection device 33 trips the 10kV bus section main power supply incoming line switch while simultaneously tripping the first switch 313 and the second switch 322. The arc protection device includes an arc sensor 331 and an arc control unit 332. The arc sensor 331 monitors the first switch 313 and the second switch 322.
[0046] In actual use, the protection and control of the small generator 1 and its excitation system, the converter 22, and the phase-shifting rectifier 23 are all implemented within the converter system 2. In order to achieve the protection coverage of the entire circuit, the protection of the power line between the 10kV switch cabinet 3 and the phase-shifting rectifier 23 is implemented by the first line comprehensive protection and measurement and control device 51 and the second line comprehensive protection and measurement and control device 52 arranged in the 10kV switch cabinet 3.
[0047] Regardless of whether the first switch 313 and the second switch 322 in the 10kV switch cabinet 3 are in the local operation state or the remote operation state, the first switch 313 and the second switch 322 can only be controlled by the control system of the converter 22. The 10kV switch cabinet 3 provides necessary signals to the converter 22 control cabinet to implement the control logic. The following signals need to be sent to the control system of the converter 22 as the basis for logical control:
[0048] AC signal: The voltage of the 10kV working section A 31 busbar is sent to the converter 22 control cabinet through the first busbar voltage transformer 41, and the voltage of the 10kV working section B 32 busbar is sent to the converter 22 control cabinet through the second busbar voltage transformer 42. The first incoming line 311 switch cabinet current is sent to the converter 22 control cabinet through the first current transformer 61, and the second incoming line 321 switch cabinet current is sent to the converter 22 control cabinet through the second current transformer 62.
[0049] Switching signal: The first switch 313 and the second switch 322 correspond to the circuit breaker closing position signal, circuit breaker opening position signal, circuit breaker spring energy storage signal, switch cabinet trolley working position signal, switch cabinet trolley test position signal, switch cabinet remote control status signal, grounding switch position signal (only the 10kV switch cabinet where the grounding switch 312 is located) sent by the 10kV switch cabinet 3; the switching signals must be sent to the converter 22 control cabinet in the form of passive dry contacts.
[0050] The grounding knife 312 and the first switch 313, the second switch 322, and the converter 22 control cabinet need to realize the operation locking function.
[0051] Other parts not described belong to the prior art.
Claims
1. The wiring structure of the small generator supporting the back-pressure extraction steam turbine connected to the factory power supply is characterized by: It comprises a small generator (1), a converter system (2) and a 10 kV switch cabinet (3), wherein the converter system (2) comprises a high-voltage switch (21) connected to the small generator (1), a converter (22) connected to the high-voltage switch (21), and a phase-shifting rectifier (23) connected to the converter (22); The 10 kV switch cabinet (3) contains a 10 kV working section A busbar (31) and a 10 kV working section B busbar (32); the 10 kV working section A busbar (31) is connected to a phase-shifting rectifier transformer (23) via a first incoming line (311), and the 10 kV working section B busbar (32) is connected to the phase-shifting rectifier transformer (23) via a second incoming line (321); The phase-shifting rectifier transformer (23) is connected to the 10 kV working section A bus (31) through the first incoming line (311) and the first switch (313) in sequence, and the earth switch (312) is connected to the first incoming line (311); The phase-shifting rectifier transformer (23) is connected to the 10 kV working section B bus (32) via the second incoming line (321) and the second switch (322) in sequence; The switch quantity signals of the ground switch (312), the first switch (313) and the second switch (322) are all sent to the converter (22) control cabinet in the form of passive dry contacts.
2. The wiring structure for connecting a small generator supporting a back-pressure extraction steam turbine to the power supply of a factory according to claim 1 is characterized in that: The first switch (313) and the second switch (322) both receive an emergency trip command from the converter (22) control cabinet, a protection action trip command from the phase-shifting rectifier (23), and a protection action trip command from the small generator (1).
3. The wiring structure for connecting a small generator supporting a back-pressure extraction steam turbine to factory power supply according to claim 2 is characterized in that: The first switch (313) and the second switch (322) are locked by hard wiring, and the first switch (313) and the second switch (322) are prohibited from being closed at the same time; the earth knife (312) and the first switch (313) are mechanically locked, and the earth knife (312) and the first switch (313) are prohibited from being closed at the same time; the earth knife (312) and the second switch (322) are locked by hard wiring, and the earth knife (312) and the second switch (322) are prohibited from being closed at the same time; the earth knife (312) and the converter (22) control cabinet are locked by hard wiring, and the converter (22) control cabinet is prohibited from closing the first switch (313) and the second switch (322) when the earth knife (312) is in the closed position.
4. The wiring structure for connecting a small generator supporting a back-pressure extraction steam turbine to the factory power supply according to claim 3 is characterized in that: The voltage of the 10kV working section A bus (31) is sent to the converter (22) control cabinet through the first bus voltage transformer (41), and the voltage of the 10kV working section B bus (32) is sent to the converter (22) control cabinet through the second bus voltage transformer (42).
5. The wiring structure for connecting a small generator supporting a back-pressure extraction steam turbine to factory power supply according to claim 4 is characterized in that: The first incoming line (311) switch cabinet current is sent to the converter (22) control cabinet through the first current transformer (61); the second incoming line (321) switch cabinet current is sent to the converter (22) control cabinet through the second current transformer (62).
6. The wiring structure for connecting a small generator supporting a back-pressure extraction steam turbine to factory power supply according to claim 5 is characterized in that: The first incoming line (311) is connected to the first line comprehensive protection and measurement and control device (51) through a third current transformer (63), and the third current transformer (63) is located between the first current transformer (61) and the first switch (313); The second incoming line (321) is connected to the second line comprehensive protection and measurement and control device (52) via a fourth current transformer (64), and the fourth current transformer (64) is located between the second current transformer (62) and the second switch (322).
7. The wiring structure for connecting a small generator supporting a back-pressure extraction steam turbine to factory power supply according to claim 6 is characterized in that: The first incoming line (311) is connected to the first line integrated protection and measurement and control device (51) through a fifth current transformer (65), and the fifth current transformer (65) is located between the first current transformer (61) and the third current transformer (63); the second incoming line (321) is connected to the second line integrated protection and measurement and control device (52) through a sixth current transformer (66), and the sixth current transformer (66) is located between the second current transformer (62) and the fourth current transformer (64).
8. The wiring structure for connecting a small generator supporting a back-pressure extraction steam turbine to the factory power supply according to claim 7 is characterized in that: The first incoming line (311) is connected to the first watt-hour meter (53) via a seventh current transformer (67), and the seventh current transformer (67) is located between the first current transformer (61) and the fifth current transformer (65); The second incoming line (321) is connected to the second watt-hour meter (54) via an eighth current transformer (68), and the eighth current transformer (68) is located between the second current transformer (62) and the sixth current transformer (66).
9. The wiring structure for connecting a small generator supporting a back-pressure extraction steam turbine to factory power supply according to claim 8 is characterized in that: The first incoming line (311) is connected to the first line comprehensive protection and measurement and control device (51) through a first zero-sequence current transformer (71), and the first zero-sequence current transformer (71) is located between the first current transformer (61) and the phase-shifting rectifier (23); The second incoming line (321) is connected to the second line comprehensive protection and measurement and control device (52) through a second zero-sequence current transformer (72), and the second zero-sequence current transformer (72) is located between the second current transformer (62) and the phase-shifting rectifier (23); the earth switch (312) is connected between the first current transformer (61) and the first zero-sequence current transformer (71).
10. The wiring structure for connecting a small generator supporting a back-pressure extraction steam turbine to the factory power supply according to claim 9, characterized in that: The 10kV switch cabinet (3) is equipped with an arc protection device (33), and the arc protection action of the arc protection device (33) trips the 10kV bus section main power supply incoming line switch while simultaneously tripping the first switch (313) and the second switch (322).