Medium-voltage desulfurization bus stand-by power supply connecting structure of coal-fired power generating unit

Abstract

The embodiment of the utility model provides a coal-fired generating set medium-voltage desulfurization bus stand-by power supply connection structure, which relates to the technical field of power stations and comprises a power supply circuit, at least two sections of unit medium-voltage buses and at least two sections of unit medium-voltage desulfurization buses in one-to-one correspondence with the at least two sections of unit medium-voltage buses. Wherein the output end of the power supply circuit is respectively connected to the at least two sections of unit medium-voltage buses; the first input end of any section of unit medium-voltage desulfurization bus is connected with the corresponding unit medium-voltage bus, and the second input end of any section of unit medium-voltage desulfurization bus is connected with the other section of unit medium-voltage desulfurization bus. Compared with a conventional medium-voltage desulfurization bus stand-by power supply connecting structure, the working power supply and the stand-by power supply of the unit medium-voltage desulfurization bus are from the unit medium-voltage bus, and the stand-by power supply can be automatically switched. And the length of a standby power supply cable is effectively saved, the initial investment of a power plant is reduced, the reliability of an auxiliary power supply is improved, and extremely high economic value and practical value are achieved.

Description

Technical Field

[0001] This utility model relates to the field of power plant technology, and more specifically, to a backup power supply connection structure for a medium-voltage desulfurization busbar of a coal-fired generator set. Background Technology

[0002] For medium-voltage desulfurization busbars of coal-fired power generating units, the conventional scheme is to draw the working power from the medium-voltage busbar of the corresponding unit in this section, and to draw the backup power from another desulfurization busbar section by setting up a medium-voltage desulfurization busbar interconnection switch; or to provide it from the medium-voltage busbar of another unit.

[0003] For the former type of backup power connection structure, the regulations and standards, based on risk protection considerations to avoid the escalation of accidents and the possibility of a local fault leading to a global fault, require that the backup power supply be manually activated.

[0004] For the latter type of backup power connection structure, although the backup power can adopt fast automatic transfer, it is necessary to add a backup power circuit breaker to the medium voltage bus of the unit. Generally, the medium voltage desulfurization bus is arranged locally in the desulfurization area, and the backup power cable is very long, resulting in poor economic efficiency. Utility Model Content

[0005] The present invention provides a backup power supply connection structure for the medium-voltage desulfurization busbar of a coal-fired power generation unit to solve the technical problems existing in the prior art.

[0006] Other features and advantages of this invention will become apparent from the following detailed description, or may be learned in part by practice of this invention.

[0007] According to a first aspect of the present utility model, a backup power supply connection structure for a medium-voltage desulfurization busbar of a coal-fired power generation unit is provided, comprising: a power supply circuit, at least two sections of medium-voltage busbars of the unit, and at least two sections of medium-voltage desulfurization busbars of the unit corresponding one-to-one with the at least two sections of medium-voltage busbars of the unit.

[0008] The output terminals of the power supply circuit are respectively connected to the medium-voltage busbars of the at least two units;

[0009] The first input terminal of any unit's medium-pressure desulfurization busbar is connected to the corresponding unit's medium-pressure busbar, and the second input terminal is connected to another unit's medium-pressure desulfurization busbar.

[0010] In some embodiments of this utility model, based on the foregoing scheme, the power supply circuit includes: a generator and a high-voltage plant service transformer;

[0011] The generator is used to generate power, and the output terminal of the generator is connected to the input terminal of the high-voltage plant transformer.

[0012] The output terminals of the high-voltage plant service transformer are respectively connected to at least two sections of the unit's medium-voltage busbar.

[0013] In some embodiments of this utility model, based on the aforementioned scheme, an incoming medium-voltage circuit breaker is respectively installed between the high-voltage plant service transformer and at least two sections of the unit's medium-voltage busbar.

[0014] In some embodiments of this utility model, based on the aforementioned scheme, an outgoing medium-voltage circuit breaker and an incoming medium-voltage circuit breaker are provided between the first input end of any section of the unit's medium-voltage desulfurization busbar and its corresponding unit medium-voltage busbar.

[0015] In some embodiments of this utility model, based on the aforementioned scheme, the second input terminal of any section of the medium-pressure desulfurization busbar of a generating unit is connected to the upper port of the incoming medium-pressure circuit breaker on another section of the medium-pressure desulfurization busbar of a generating unit.

[0016] In some embodiments of this utility model, based on the foregoing scheme, the at least two sections of the unit's medium-pressure busbar include: a first unit medium-pressure busbar and a second unit medium-pressure busbar; the at least two sections of the unit's medium-pressure desulfurization busbar include: a first unit medium-pressure desulfurization busbar and a second unit medium-pressure desulfurization busbar;

[0017] Wherein, the first input terminal of the medium-pressure desulfurization busbar of the first unit is connected to the medium-pressure busbar of the first unit, and the second input terminal of the medium-pressure desulfurization busbar of the first unit is connected to the upper port of the incoming medium-pressure circuit breaker on the medium-pressure desulfurization busbar of the second unit.

[0018] The first input terminal of the medium-pressure desulfurization busbar of the second unit is connected to the medium-pressure busbar of the second unit, and the second input terminal of the medium-pressure desulfurization busbar of the second unit is connected to the upper port of the incoming medium-pressure circuit breaker on the medium-pressure desulfurization busbar of the first unit.

[0019] The working and backup power supplies of the unit's medium-voltage desulfurization busbar in this utility model are both derived from the unit's medium-voltage busbar, and the backup power supply can be automatically switched on. This avoids the problem that the backup power supply cannot be automatically switched on when a tie switch is installed between the unit's medium-voltage desulfurization busbars. Furthermore, it effectively saves the length of the backup power cable, reduces the initial investment of the power plant, and improves the reliability of the plant's power supply, thus possessing extremely high economic and practical value.

[0020] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit the present invention. Attached Figure Description

[0021] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments conforming to the present invention and, together with the description, serve to explain the principles of the present invention. Obviously, the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings:

[0022] Figure 1 A schematic diagram of a backup power supply connection structure for a medium-voltage desulfurization busbar in a coal-fired generator set according to an embodiment of the present invention is shown. Detailed Implementation

[0023] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make the present invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0024] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a full understanding of embodiments of the present invention. However, those skilled in the art will recognize that the technical solutions of the present invention can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., may be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of the present invention.

[0025] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such uses of terms can be interchanged where appropriate so that the embodiments of this utility model described herein can be implemented in orders other than those shown or described.

[0026] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0027] The following description, in conjunction with the accompanying drawings, details some embodiments of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0028] To address the technical problems existing in the prior art, this utility model provides a backup power supply connection structure for the medium-voltage desulfurization busbar of a coal-fired power generation unit.

[0029] Specifically, the structure includes: a power supply circuit, at least two sections of medium-voltage busbars for the unit, and at least two sections of medium-voltage desulfurization busbars for the unit that correspond one-to-one with the at least two sections of medium-voltage busbars for the unit.

[0030] The output terminals of the power supply circuit are respectively connected to the medium-voltage busbars of the at least two units;

[0031] The first input terminal of any unit's medium-pressure desulfurization busbar is connected to the corresponding unit's medium-pressure busbar, and the second input terminal is connected to another unit's medium-pressure desulfurization busbar.

[0032] It should be noted that, in this embodiment, the first input terminal of the unit's medium-pressure desulfurization bus is used to receive working power from the corresponding unit's medium-pressure bus, and the second input terminal is used to receive backup power from another section of the unit's medium-pressure bus.

[0033] It is understood that in this embodiment, the working power and backup power of any section of the unit's medium-pressure desulfurization busbar are provided by the unit's medium-pressure busbar, ensuring that the backup power can be automatically switched on.

[0034] In some feasible embodiments, based on the foregoing scheme, the power supply circuit includes: a generator and a high-voltage plant service transformer;

[0035] The generator is used to generate power, and the output terminal of the generator is connected to the input terminal of the high-voltage plant transformer.

[0036] The output terminals of the high-voltage plant service transformer are respectively connected to at least two sections of the unit's medium-voltage busbar.

[0037] Understandably, high-voltage plant service transformers can convert high-voltage electricity into a voltage level suitable for the medium-voltage busbar requirements of the generating unit.

[0038] In some feasible embodiments, based on the aforementioned scheme, an incoming medium-voltage circuit breaker is respectively installed between the high-voltage plant service transformer and at least two sections of the unit's medium-voltage busbar.

[0039] As we can understand, an incoming medium-voltage circuit breaker is a switching device used in medium-voltage power systems (typically referring to voltage levels of 1-35kV). "Incoming" indicates its location and function within the power system; it is generally installed at the incoming end of a substation or distribution room, responsible for introducing external power into the station or indoor electrical system. The "circuit breaker" is the core functional component; it can connect and disconnect circuits during normal operation, and when faults such as short circuits or overloads occur, it can quickly interrupt the fault current, protecting the safe and stable operation of electrical equipment and the power system. Incoming medium-voltage circuit breakers typically have high breaking capacity and reliability, employing arc-extinguishing devices to extinguish the electric arc, ensuring that equipment is not damaged when interrupting fault currents. Common types include vacuum circuit breakers and SF6 circuit breakers.

[0040] In some feasible embodiments, based on the aforementioned scheme, an outgoing medium-voltage circuit breaker and an incoming medium-voltage circuit breaker are installed between the first input terminal of any unit's medium-voltage desulfurization busbar and its corresponding unit medium-voltage busbar.

[0041] For example, in this embodiment, the connection structure includes at least a unit medium-voltage busbar A and a unit medium-voltage desulfurization busbar A connected to the unit medium-voltage busbar A. The unit medium-voltage busbar A and the unit medium-voltage desulfurization busbar A are sequentially equipped with an outgoing medium-voltage circuit breaker A and an incoming medium-voltage circuit breaker A. The output terminal of the unit medium-voltage busbar A is connected to the input terminal of the outgoing medium-voltage circuit breaker A, the output terminal of the outgoing medium-voltage circuit breaker A is connected to the output terminal of the incoming medium-voltage circuit breaker A, and the output terminal of the incoming medium-voltage circuit breaker A is connected to the first input terminal of the unit medium-voltage desulfurization busbar A.

[0042] In some feasible embodiments, based on the aforementioned scheme, the second input terminal of any section of the medium-voltage desulfurization busbar of a generating unit is connected to the upper port of the incoming medium-voltage circuit breaker on another section of the medium-voltage desulfurization busbar of a generating unit.

[0043] For example, the connection structure in this embodiment includes at least a unit medium-voltage busbar A, a unit medium-voltage busbar B, a unit medium-voltage desulfurization busbar A connected to the unit medium-voltage busbar A, and a unit medium-voltage desulfurization busbar B connected to the unit medium-voltage busbar B. The unit medium-voltage busbar A and the unit medium-voltage desulfurization busbar A are sequentially equipped with an outgoing medium-voltage circuit breaker A and an incoming medium-voltage circuit breaker A, respectively. The unit medium-voltage busbar B and the unit medium-voltage desulfurization busbar B are sequentially equipped with an outgoing medium-voltage circuit breaker B and an incoming medium-voltage circuit breaker B. The second input terminal of the unit medium-voltage desulfurization busbar A is connected to the upper port (i.e., the input terminal of the incoming medium-voltage circuit breaker B) of the incoming medium-voltage circuit breaker B via a medium-voltage circuit breaker, and the second input terminal of the unit medium-voltage desulfurization busbar B is connected to the upper port (i.e., the input terminal of the incoming medium-voltage circuit breaker A) of the incoming medium-voltage circuit breaker A via a medium-voltage circuit breaker.

[0044] In some feasible embodiments, based on the foregoing scheme, the at least two units of medium-pressure busbars include: a first unit medium-pressure busbar and a second unit medium-pressure busbar; the at least two units of medium-pressure desulfurization busbars include: a first unit medium-pressure desulfurization busbar and a second unit medium-pressure desulfurization busbar;

[0045] Wherein, the first input terminal of the medium-pressure desulfurization busbar of the first unit is connected to the medium-pressure busbar of the first unit, and the second input terminal of the medium-pressure desulfurization busbar of the first unit is connected to the upper port of the incoming medium-pressure circuit breaker on the medium-pressure desulfurization busbar of the second unit.

[0046] The first input terminal of the medium-pressure desulfurization busbar of the second unit is connected to the medium-pressure busbar of the second unit, and the second input terminal of the medium-pressure desulfurization busbar of the second unit is connected to the upper port of the incoming medium-pressure circuit breaker on the medium-pressure desulfurization busbar of the first unit.

[0047] It should be noted that, in this embodiment, an outgoing medium-voltage circuit breaker and an incoming medium-voltage circuit breaker are installed between the medium-voltage busbar of the first unit and the medium-voltage desulfurization busbar of the first unit, respectively denoted as the first outgoing medium-voltage circuit breaker and the first incoming medium-voltage circuit breaker; an outgoing medium-voltage circuit breaker and an incoming medium-voltage circuit breaker are installed between the medium-voltage busbar of the second unit and the medium-voltage desulfurization busbar of the second unit, respectively denoted as the second outgoing medium-voltage circuit breaker and the second incoming medium-voltage circuit breaker; wherein, the output terminal of the medium-voltage busbar of the first unit is sequentially connected to the first outgoing medium-voltage circuit breaker and the first incoming medium-voltage circuit breaker. After the circuit breaker is connected, it is connected to the first input terminal of the medium-voltage desulfurization busbar of the first unit. The second input terminal of the medium-voltage desulfurization busbar of the first unit is connected to the upper port of the second incoming medium-voltage circuit breaker (i.e., the input terminal of the second incoming medium-voltage circuit breaker). The output terminal of the medium-voltage busbar of the second unit is connected to the second outgoing medium-voltage circuit breaker and the second incoming medium-voltage circuit breaker in sequence, and then connected to the first input terminal of the medium-voltage desulfurization busbar of the second unit. The second input terminal of the medium-voltage desulfurization busbar of the second unit is connected to the upper port of the first incoming medium-voltage circuit breaker (i.e., the input terminal of the first incoming medium-voltage circuit breaker).

[0048] For example, see Figure 1 The diagram shows a schematic diagram of a backup power supply connection structure for a medium-voltage desulfurization busbar of a coal-fired generator set according to an embodiment of the present invention.

[0049] like Figure 1 As shown, the connection structure includes: a generator, a high-voltage plant service transformer (i.e., a high-voltage plant service transformer), a medium-voltage A section of the unit, a medium-voltage B section of the unit, a medium-voltage desulfurization A section of the unit, and a medium-voltage desulfurization B section of the unit.

[0050] The generator's output terminal is connected to the output terminal of the high-voltage station service transformer. The output terminal of the high-voltage station service transformer is connected to the input terminals of the medium-voltage A section and the medium-voltage B section of the unit, respectively. An incoming medium-voltage circuit breaker is installed between the output terminal of the high-voltage station service transformer and the input terminal of the medium-voltage A section of the unit. Similarly, an incoming medium-voltage circuit breaker is also installed between the output terminal of the high-voltage station service transformer and the input terminal of the medium-voltage B section of the unit.

[0051] A medium-pressure A section of the unit and its corresponding medium-pressure desulfurization A section are connected in sequence with an outgoing medium-pressure circuit breaker and an incoming medium-pressure circuit breaker. Similarly, a medium-pressure B section of the unit and its corresponding medium-pressure desulfurization B section are also connected in sequence with an outgoing medium-pressure circuit breaker and an incoming medium-pressure circuit breaker.

[0052] The first input terminal of the unit's medium-pressure desulfurization section A is connected to the lower port (i.e., output terminal) of the incoming medium-pressure circuit breaker between the unit's medium-pressure desulfurization section A and the unit's medium-pressure section A. The second input terminal is connected to the upper port (i.e., input terminal) of the incoming medium-pressure circuit breaker between the unit's medium-pressure desulfurization section B and the unit's medium-pressure section B. Similarly, the first input terminal of the unit's medium-pressure desulfurization section B is connected to the lower port (i.e., output terminal) of the incoming medium-pressure circuit breaker between the unit's medium-pressure desulfurization section B and the unit's medium-pressure section B. The second input terminal is connected to the upper port (i.e., input terminal) of the incoming medium-pressure circuit breaker between the unit's medium-pressure desulfurization section A and the unit's medium-pressure section A.

[0053] like Figure 1 As shown, an incoming medium-voltage circuit breaker is also installed between the second input terminal of the unit's medium-voltage desulfurization section A and the upper port of the incoming medium-voltage circuit breaker between the unit's medium-voltage desulfurization section B and the unit's medium-voltage section B. Similarly, an incoming medium-voltage circuit breaker is also installed between the second input terminal of the unit's medium-voltage desulfurization section B and the upper port of the incoming medium-voltage circuit breaker between the unit's medium-voltage desulfurization section A and the unit's medium-voltage section A.

[0054] In summary, the backup power supply for the desulfurization busbar of this scheme is drawn from the upper port of the medium-voltage circuit breaker of the incoming line of the desulfurization busbar of another unit. The backup power supply can adopt fast switching and automatic transfer; and no dedicated backup power medium-voltage circuit breaker is required; the medium-voltage desulfurization busbars of the two units are arranged in the same distribution room, and the backup power cable is very short.

[0055] Compared to conventional medium-voltage desulfurization busbar backup power supply connection structures, this utility model's unit's medium-voltage desulfurization busbar's working and backup power supplies both originate from the unit's medium-voltage busbar, with the backup power supply capable of automatic switching. This avoids the problem of having a tie switch between the unit's medium-voltage desulfurization busbars, which prevents automatic backup power supply switching. Furthermore, it effectively saves on backup power cable length, reduces initial investment in the power plant, and improves the reliability of plant power supplies, possessing extremely high economic and practical value.

[0056] Other embodiments of the present invention will readily occur to those skilled in the art upon consideration of the specification and practice of the embodiments disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. It should be understood that the present invention is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A backup power supply connection structure for a medium-voltage desulfurization busbar in a coal-fired power generating unit, characterized in that, include: The power supply circuit, at least two sections of medium-voltage busbars for the unit, and at least two sections of medium-voltage desulfurization busbars for the unit that correspond one-to-one with the at least two sections of medium-voltage busbars for the unit; The output terminals of the power supply circuit are respectively connected to the medium-voltage busbars of the at least two units; The first input terminal of any unit's medium-pressure desulfurization busbar is connected to the corresponding unit's medium-pressure busbar, and the second input terminal is connected to another unit's medium-pressure desulfurization busbar.

2. The lead-in structure according to claim 1, characterized in that, The power supply circuit includes: a generator and a high-voltage plant transformer; The generator is used to generate power, and the output terminal of the generator is connected to the input terminal of the high-voltage plant transformer. The output terminals of the high-voltage plant service transformer are respectively connected to at least two sections of the unit's medium-voltage busbar.

3. The lead-in structure according to claim 1, characterized in that, A medium-voltage circuit breaker is installed between the high-voltage plant transformer and at least two sections of the unit's medium-voltage busbar.

4. The lead-in structure according to claim 1, characterized in that, An outgoing medium-voltage circuit breaker and an incoming medium-voltage circuit breaker are installed between the first input terminal of any unit's medium-voltage desulfurization busbar and its corresponding unit's medium-voltage busbar.

5. The lead-in structure according to claim 4, characterized in that, The second input terminal of any section of the medium-voltage desulfurization busbar is connected to the upper port of the incoming medium-voltage circuit breaker on another section of the medium-voltage desulfurization busbar.

6. The lead-in structure according to claim 5, characterized in that, The at least two sections of the unit's medium-pressure busbar include: a first unit's medium-pressure busbar and a second unit's medium-pressure busbar; the at least two sections of the unit's medium-pressure desulfurization busbar include: a first unit's medium-pressure desulfurization busbar and a second unit's medium-pressure desulfurization busbar; Wherein, the first input terminal of the medium-pressure desulfurization busbar of the first unit is connected to the medium-pressure busbar of the first unit, and the second input terminal of the medium-pressure desulfurization busbar of the first unit is connected to the upper port of the incoming medium-pressure circuit breaker on the medium-pressure desulfurization busbar of the second unit. The first input terminal of the medium-pressure desulfurization busbar of the second unit is connected to the medium-pressure busbar of the second unit, and the second input terminal of the medium-pressure desulfurization busbar of the second unit is connected to the upper port of the incoming medium-pressure circuit breaker on the medium-pressure desulfurization busbar of the first unit.

Images