Generator grid-connected state judgment device and special terminal box

Abstract

The utility model discloses a generator grid-connected state determination device and a special terminal box, comprising a first circuit comprising two groups of auxiliary nodes of a 6kV side isolation switch which are connected in parallel, two groups of auxiliary nodes of a 35kV side isolation switch which are connected in parallel, and two groups of auxiliary nodes of a 110kV side isolation switch which are connected in parallel, the two groups of auxiliary nodes of the 35kV-side isolating switch are connected in parallel with the two groups of auxiliary nodes of the 110kV-side isolating switch and then are connected in series with the two groups of auxiliary nodes of the 6kV-side isolating switch; the second circuit comprises two groups of auxiliary nodes of the 6kV-side circuit breaker which are connected in parallel, two groups of auxiliary nodes of the 35kV-side circuit breaker which are connected in parallel and two groups of auxiliary nodes of the 110kV-side circuit breaker which are connected in parallel, and the two groups of auxiliary nodes of the 35kV-side circuit breaker are connected in parallel with the two groups of auxiliary nodes of the 110kV-side circuit breaker and then are connected in series with the two groups of auxiliary nodes of the 6kV-side circuit breaker; and the generator protection device judges the grid-connected state of the generator based on the output signals at the two ends of the first circuit and the output signals at the two ends of the second circuit.

Description

TECHNICAL FIELD

[0001] The utility model relates to electrical technology field, especially relate to a generator grid-connected state determination device. BACKGROUND

[0002] The main transformer of power plant, especially self-provided power plant, often adopts multi-coil transformer, please refer to Figure 1 , Figure 1 The primary wiring diagram of generator transformer set, the generator side is often configured with generator switch, whether the generator switch is in grid-connected state is difficult to determine, needs 3-4 isolating switches auxiliary switch contacts and 3-4 circuit breakers auxiliary switch contacts to jointly determine, needs the 3-4 isolating switches auxiliary switch contacts and 3-4 circuit breakers auxiliary switch contacts to be connected into generator protection or DEH speed regulation system respectively, then by the generator protection or DEH speed regulation system builds logic to realize generator grid-connected state judgment, increases I / O input interface, increases logic calculation burden, and the generator protection or DEH speed regulation system etc. do not have so many I / O points to connect these input signals, and the grid-connected signal directly participates in generator shutdown and load reduction protection, improper signal determination and easy to cause generator tripping or false load reduction, the position of each isolating switch and circuit breaker auxiliary switch contact is far from the generator protection device, is about 100-200 meters on average, and 12 cables are laid, the probability of signal attenuation and interference greatly increases.If in the generator grid-connected power generation state, due to the poor contact of generator auxiliary switch contact in operation due to shaking, rust and other reasons, the generator auxiliary contact switch signal is misjudged from "1" to "0" due to poor contact, and the generator grid-connected state is misjudged as generator disengaging from grid-connected state;Or due to cable interference fluctuation, 24V voltage signal is misjudged from high voltage level to low voltage level, so that the generator grid-connected state is misjudged as generator disengaging from grid-connected state, and false load reduction and shutdown occur.

[0003] Therefore, a reliable generator grid-connected state determination device needs to be proposed to ensure stable operation of the generator. UTILITY MODEL CONTENT

[0004] The utility model provides a kind of generator grid-connected state determination device, avoids the misjudgment of generator grid-connected state, leads to false load reduction or shutdown situation.

[0005] In order to solve the above technical problems, realize the purpose of the utility model, the utility model provides a kind of determination device of generator grid-connected state, comprising:

[0006] The first circuit comprises two groups of auxiliary nodes of 6kV side disconnectors in parallel, two groups of auxiliary nodes of 35kV side disconnectors in parallel and two groups of auxiliary nodes of 110kV side disconnectors in parallel, wherein the two groups of auxiliary nodes of the 35kV side disconnectors are connected in parallel with the two groups of auxiliary nodes of the 110kV side disconnectors, and then connected in series with the two groups of auxiliary nodes of the 6kV side disconnectors;

[0007] The second circuit comprises two groups of auxiliary nodes of 6kV side circuit breakers in parallel, two groups of auxiliary nodes of 35kV side circuit breakers in parallel and two groups of auxiliary nodes of 110kV side circuit breakers in parallel, wherein the two groups of auxiliary nodes of the 35kV side circuit breakers are connected in parallel with the two groups of auxiliary nodes of the 110kV side circuit breakers, and then connected in series with the two groups of auxiliary nodes of the 6kV side circuit breakers;

[0008] The generator protection device judges the grid-connected state of the generator based on the output signal between the two ends of the first circuit and the output signal between the two ends of the second circuit.

[0009] Optionally, the 6kV side disconnector is closed, and at least one of the 35kV side disconnector and the 110kV side disconnector is closed, and the output signal between the two ends of the first circuit is 1.

[0010] Optionally, the 6kV side circuit breaker is closed, and at least one of the 35kV side circuit breaker and the 110kV side circuit breaker is closed, and the output signal between the two ends of the second circuit is 1.

[0011] Optionally, the output signal between the two ends of the first circuit is 1, and the output signal between the two ends of the second circuit is 1, and the generator protection device judges that the generator is in a grid-connected state.

[0012] Optionally, the output signal between the two ends of the first circuit is 1, and the output signal between the two ends of the second circuit is 0, and the generator protection device judges that the generator is in a hot standby state.

[0013] Optionally, the output signal between the two ends of the first circuit is 0, and the output signal between the two ends of the second circuit is 1, and the generator protection device judges that the generator is in a false grid-connected state.

[0014] Optionally, the output signal between the two ends of the first circuit is 0, and the output signal between the two ends of the second circuit is 0, and the generator protection device judges that the generator is in a cold standby state.

[0015] In another aspect, the utility model provides a kind of special terminal box of generator grid-connected state judging device, comprising:

[0016] 12 first circuit terminals, externally for connecting two groups of auxiliary nodes of 6kV side disconnectors, two groups of auxiliary nodes of 35kV side disconnectors and two groups of auxiliary nodes of 110kV side disconnectors, internally connecting the two groups of auxiliary nodes of 6kV side disconnectors in parallel, the two groups of auxiliary nodes of 35kV side disconnectors in parallel and the two groups of auxiliary nodes of 110kV side disconnectors in parallel, and connecting the two groups of auxiliary nodes of 35kV side disconnectors and the two groups of auxiliary nodes of 110kV side disconnectors in parallel, and then connecting the two groups of auxiliary nodes of 6kV side disconnectors in series;

[0017] 12 second circuit terminals, externally for connecting two groups of auxiliary nodes of 6kV side circuit breakers, two groups of auxiliary nodes of 35kV side circuit breakers and two groups of auxiliary nodes of 110kV side circuit breakers, internally connecting the two groups of auxiliary nodes of 6kV side circuit breakers in parallel, the two groups of auxiliary nodes of 35kV side circuit breakers in parallel and the two groups of auxiliary nodes of 110kV side circuit breakers in parallel, and connecting the two groups of auxiliary nodes of 35kV side circuit breakers and the two groups of auxiliary nodes of 110kV side circuit breakers in parallel, and then connecting the two groups of auxiliary nodes of 6kV side circuit breakers in series;

[0018] 4 output signal terminals, internally connected with two ends of the first circuit and two ends of the second circuit respectively, and externally for connecting the two ends of the first circuit and the two ends of the second circuit to a generator protection device.

[0019] Compared with the prior art, the technical scheme of the utility model has the following beneficial effects:

[0020] 1. The generator grid-connected state judging device provided by the utility model takes 2 groups of normally open auxiliary nodes from the main transformer 6KV side disconnector, the main transformer 35KV side disconnector and the main transformer 110KV side disconnector respectively, and connects them in parallel, takes 2 groups of signal nodes from each disconnector, avoids the misjudgment of the generator auxiliary node switch signal from "1" to "0" due to poor contact, and ensures the signal reliability.

[0021] 2. The special terminal box provided by the utility model can save 10 cables by directly connecting each signal to the generator protection device, avoid the misjudgment of the 24V voltage signal from high voltage level to low voltage level due to cable interference, save 10 groups of generator protection input I / O nodes, reduce the generator protection calculation and judgment time, and improve the protection action accuracy and reliability. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 It is a generator transformer set primary wiring diagram;

[0023] Figure 2The utility model discloses a structure diagram of the generator grid-connected state judging device of one embodiment of the utility model.

[0024] Figure 3 The utility model discloses a structure diagram of the special terminal box of the generator grid-connected state judging device of one embodiment of the utility model. DETAILED DESCRIPTION

[0025] The utility model discloses a kind of generator grid-connected state judging devices proposed in the following detailed description and specific embodiments.It will be more clear that the advantages and features of the utility model according to the following description.It should be noted that the drawings are very simplified and all use non-precise scale, just to facilitate, clearly assist the purpose of explaining the embodiment of the utility model.For the purpose, features and advantages of the utility model can be more obvious and easy to understand, please refer to the drawings.It is known that the structure, proportion, size etc. shown in the drawings attached to this specification, are just to cooperate with the content disclosed in the specification, for understanding and reading by person skilled in the art, and not to limit the limiting conditions of the implementation of the utility model, so it does not have the substantial meaning of technology, any modification of structure, change of proportion relationship or adjustment of size, under the condition that it does not affect the effect and the purpose that can be achieved by the utility model, should still fall within the range that the technical content disclosed by the utility model can cover.

[0026] Please refer to Figure 2 , Figure 2 The utility model discloses a generator grid-connected state judging device, comprising:

[0027] First circuit, the first circuit includes two groups of auxiliary nodes of 6kV side isolating switch in parallel, two groups of auxiliary nodes of 35kV side isolating switch in parallel and two groups of auxiliary nodes of 110kV side isolating switch in parallel, wherein, two groups of auxiliary nodes of 35kV side isolating switch and two groups of auxiliary nodes of 110kV side isolating switch are in parallel, and then in series with two groups of auxiliary nodes of 6kV side isolating switch;

[0028] Second circuit, the second circuit includes two groups of auxiliary nodes of 6kV side circuit breaker in parallel, two groups of auxiliary nodes of 35kV side circuit breaker in parallel and two groups of auxiliary nodes of 110kV side circuit breaker in parallel, wherein, two groups of auxiliary nodes of 35kV side circuit breaker and two groups of auxiliary nodes of 110kV side circuit breaker are in parallel, and then in series with two groups of auxiliary nodes of 6kV side circuit breaker;

[0029] Generator protection device, the generator protection device judges the grid-connected state of the generator based on the output signal of the two ends of first circuit, the output signal of the two ends of second circuit.

[0030] Take 2 groups of normally open auxiliary nodes from the main transformer 6KV side disconnector, the main transformer 35KV side disconnector and the main transformer 110KV side disconnector respectively, and connect them in parallel, the main purpose is to take 2 groups of signal nodes for each disconnector signal, to ensure the reliability of the signal and avoid the misjudgment of the switch signal of the generator auxiliary node from "1" to "0" due to poor contact.

[0031] Connect the main transformer 35KV side disconnector and the main transformer 110KV side disconnector in parallel, and then connect them in series with the main transformer 6KV side disconnector, the output signal terminals GL1 and GL2 at both ends of the first circuit, when the main transformer 6KV side disconnector is closed, and at least one of the main transformer 35KV side disconnector and the main transformer 110KV side disconnector is closed, the output signal between GL1 and GL2 is 1, and the rest is 0.

[0032] Take 2 groups of normally open auxiliary nodes from the main transformer 6KV side disconnector, the main transformer 35KV side disconnector and the main transformer 110KV side disconnector respectively, and connect them in parallel, the main purpose is to take 2 groups of signal nodes for each disconnector signal, to ensure the reliability of the signal.

[0033] Connect the main transformer 35KV side disconnector and the main transformer 110KV side disconnector in parallel, and then connect them in series with the main transformer 6KV side disconnector, the output signal terminals GL1 and GL2 at both ends of the first circuit, when the main transformer 6KV side disconnector is closed, and at least one of the main transformer 35KV side disconnector and the main transformer 110KV side disconnector is closed, the output signal between GL1 and GL2 is 1, and the rest is 0.

[0034] The output signal between GL1 and GL2 at both ends of the first circuit is 1, and the output signal between DL1 and DL2 at both ends of the second circuit is 1, which determines that the generator is in parallel state; the parallel state means that the disconnector and the circuit breaker of the generator are in the closed position, and the generator will deliver power to the power grid.

[0035] The output signal between GL1 and GL2 at both ends of the first circuit is 1, and the output signal between DL1 and DL2 at both ends of the second circuit is 0, which determines that the generator is in hot standby state; the hot standby state means that the disconnector of the generator is in the closed position, and the circuit breaker is in the open position, the generator has the conditions for power transmission and start-up, and the circuit breaker will be closed as soon as possible, and the generator will be changed to the parallel state.

[0036] The output signal between GL1 and GL2 at both ends of the first circuit is 0, and the output signal between DL1 and DL2 at both ends of the second circuit is 1, which determines that the generator is in false parallel state; the false parallel state means that the disconnector of the generator is in the open position, and the circuit breaker is in the closed position, this state is mainly used for parameter measurement and setting of generator parallel synchronization device, debugging of generator DEH speed regulation loop, debugging of generator protection, etc.

[0037] The output signal between the first circuit GL1 and GL2 is 0, the output signal between the second circuit DL1 and DL2 is 0, and it is judged that the generator is in a cold standby state.

[0038] The generator grid-connected state judging device provided by the utility model takes 2 groups of normally-open auxiliary nodes from the main transformer 6KV side isolating switch, the main transformer 35KV side isolating switch and the main transformer 110KV side isolating switch respectively, and connects them in parallel respectively, takes 2 groups of signal nodes from each isolating switch, avoids that the generator auxiliary node switch signal is misjudged from 1 to 0 due to poor contact, and guarantees the signal reliability

[0039] The embodiment further provides a special terminal box of the generator grid-connected state judging device, please refer to Figure 3 , Figure 3 It is a structural schematic view of the special terminal box of the generator grid-connected state judging device of the embodiment of the utility model, and it comprises:

[0040] 12 first circuit wiring terminals, which are externally used for connecting two groups of auxiliary nodes of the 6kV side isolating switch, two groups of auxiliary nodes of the 35kV side isolating switch and two groups of auxiliary nodes of the 110kV side isolating switch, and internally parallelly connecting the two groups of auxiliary nodes of the 6kV side isolating switch, the two groups of auxiliary nodes of the 35kV side isolating switch and the two groups of auxiliary nodes of the 110kV side isolating switch, and parallelly connecting the two groups of auxiliary nodes of the 35kV side isolating switch and the two groups of auxiliary nodes of the 110kV side isolating switch and then serially connecting the two groups of auxiliary nodes of the 6kV side isolating switch;

[0041] 12 second circuit wiring terminals, which are externally used for connecting two groups of auxiliary nodes of the 6kV side circuit breaker, two groups of auxiliary nodes of the 35kV side circuit breaker and two groups of auxiliary nodes of the 110kV side circuit breaker, and internally parallelly connecting the two groups of auxiliary nodes of the 6kV side circuit breaker, the two groups of auxiliary nodes of the 35kV side circuit breaker and the two groups of auxiliary nodes of the 110kV side circuit breaker, and parallelly connecting the two groups of auxiliary nodes of the 35kV side circuit breaker and the two groups of auxiliary nodes of the 110kV side circuit breaker and then serially connecting the two groups of auxiliary nodes of the 6kV side circuit breaker;

[0042] 4 output signal wiring terminals, which are internally connected with two ends of the first circuit and two ends of the second circuit respectively, and externally used for connecting the two ends of the first circuit and the two ends of the second circuit to a generator protection device.

[0043] The special terminal box provided by the embodiment can save the cable of 10 roots, avoid the 24V voltage signal from being misjudged as a low level due to the interference wave of the cable, save 10 groups of generator protection input I / O nodes, reduce the calculation and judgment time of the generator protection, and improve the accuracy and reliability of the protection action.

[0044] It should be noted that, in the present document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises... a" does not, without more constraints, exclude the presence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0045] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "height", "thickness", "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In the description of the present application, unless otherwise specified and limited, the meaning of "a plurality of" is two or more.

[0046] In the description of the present application, unless otherwise specified and limited, the terms "mounting", "connection", "connecting", "fixing" should be understood in a broad sense, for example, can be fixedly connected, or can be detachably connected, or can be integrated; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium; can be the communication or interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0047] In the utility model, unless another definite provision and limitation, first feature is "on" or "under" second feature can include that first and second features are in direct contact, also can include that first and second features are not in direct contact but contact through other feature between them.

[0048] Although the content of the utility model has been introduced in detail through the above preferred embodiment, it should be recognized that the above description should not be considered as the limitation of the utility model. After the above content is read by the person skilled in the art, various modifications and substitutions of the utility model will be obvious. Therefore, the protection scope of the utility model should be limited by the attached claim.

Claims

1. A generator grid-connected state determination device characterized by comprising: Comprising: The first circuit comprises two groups of auxiliary nodes of 6kV side disconnectors in parallel, two groups of auxiliary nodes of 35kV side disconnectors in parallel, and two groups of auxiliary nodes of 110kV side disconnectors in parallel, wherein the two groups of auxiliary nodes of 35kV side disconnectors are connected in parallel with the two groups of auxiliary nodes of 110kV side disconnectors, and then connected in series with the two groups of auxiliary nodes of 6kV side disconnectors; The second circuit comprises two groups of auxiliary nodes of 6kV side circuit breakers in parallel, two groups of auxiliary nodes of 35kV side circuit breakers in parallel, and two groups of auxiliary nodes of 110kV side circuit breakers in parallel, wherein the two groups of auxiliary nodes of 35kV side circuit breakers are connected in parallel with the two groups of auxiliary nodes of 110kV side circuit breakers, and then connected in series with the two groups of auxiliary nodes of 6kV side circuit breakers; The generator protection device determines the grid-connected state of the generator based on the output signal between the two ends of the first circuit and the output signal between the two ends of the second circuit.

2. The generator grid-connected state determination device according to claim 1, characterized by, Comprising: The 6kV side disconnector is closed, and at least one of the 35kV side disconnector and the 110kV side disconnector is closed, and the output signal between the two ends of the first circuit is 1.

3. The generator grid-connected state determination device according to claim 2, characterized by Comprising: The 6kV side circuit breaker is closed, and at least one of the 35kV side circuit breaker and the 110kV side circuit breaker is closed, and the output signal between the two ends of the second circuit is 1.

4. The generator grid-connected state determination device according to claim 3, characterized by Comprising: The output signal between the two ends of the first circuit is 1, and the output signal between the two ends of the second circuit is 1, and the generator protection device determines that the generator is in a grid-connected state.

5. The generator grid-connected state determination device according to claim 3, wherein Comprising: The output signal between the two ends of the first circuit is 1, and the output signal between the two ends of the second circuit is 0, and the generator protection device determines that the generator is in a hot standby state.

6. The generator grid-connected state determination device according to claim 3, wherein Comprising: The output signal between the two ends of the first circuit is 0, and the output signal between the two ends of the second circuit is 1, and the generator protection device determines that the generator is in a false grid-connected state.

7. The generator grid-connected state determination device according to claim 3, wherein Comprising: The output signal between the two ends of the first circuit is 0, and the output signal between the two ends of the second circuit is 0, and the generator protection device determines that the generator is in a cold standby state.

8. A terminal box for a generator grid-connection state determination device, characterized by Comprising: 12 first circuit terminals, externally connected to two groups of auxiliary nodes of 6kV side disconnectors, two groups of auxiliary nodes of 35kV side disconnectors, and two groups of auxiliary nodes of 110kV side disconnectors, and internally connected in parallel to the two groups of auxiliary nodes of 6kV side disconnectors, the two groups of auxiliary nodes of 35kV side disconnectors, and the two groups of auxiliary nodes of 110kV side disconnectors, and then connected in series to the two groups of auxiliary nodes of 6kV side disconnectors in parallel with the two groups of auxiliary nodes of 35kV side disconnectors and the two groups of auxiliary nodes of 110kV side disconnectors; 12 second circuit terminals, externally for connecting two groups of auxiliary nodes of 6kV side circuit breaker, two groups of auxiliary nodes of 35kV side circuit breaker and two groups of auxiliary nodes of 110kV side circuit breaker, internally connecting two groups of auxiliary nodes of 6kV side circuit breaker in parallel, two groups of auxiliary nodes of 35kV side circuit breaker in parallel and two groups of auxiliary nodes of 110kV side circuit breaker in parallel, and connecting two groups of auxiliary nodes of 35kV side circuit breaker and two groups of auxiliary nodes of 110kV side circuit breaker in parallel, and connecting two groups of auxiliary nodes of 6kV side circuit breaker in series; 4 output signal terminals, internally connected with two ends of the first circuit and two ends of the second circuit respectively, externally for connecting two ends of the first circuit and two ends of the second circuit to a generator protection device.

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