Switching device special for new energy power generation
By introducing current limiting components and optimized control strategies into the combined electrical appliances, the impact of closing inrush current on the equipment is solved, and the stable operation and efficient heat dissipation of equipment in the new energy power generation system is achieved.
Patent Information
- Application Number
- CN202422153116.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-03
- Publication Date
- 2025-06-27
- Estimated Expiration
- 2034-09-03
AI Technical Summary
In combined electrical appliances, the closing surge current generated during the circuit breaker closing process will cause impact on load transformers and other equipment, which may lead to insulation damage, arcing, heat or burning of contacts, and affect the normal operation of other equipment.
A special switching device for new energy power generation is designed, including an isolation knife switch, circuit breaker and current limiting element. The power supply circuit is preferred to be connected to the power supply circuit through the current limiting element to reduce the impact of the closing inrush current on the equipment, and the closing of the circuit breaker two K2 is controlled by delay to ensure the stable operation of the load transformer.
It effectively reduces the damage caused by the closing inrush current to load transformers and other equipment in the transmission line, ensures the stable operation of the equipment, and improves the overall heat dissipation effect of the combined electrical appliances by optimizing the heat dissipation design.
Smart Images
Figure CN223038891U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of new energy power generation systems, and in particular, to a switching device dedicated for new energy power generation. Background Art
[0002] Both wind power generation and photovoltaic power generation are widely used clean energy power generation methods. In the transmission lines of new energy, the switching device is one of the essential components. The combined electrical apparatus in the switching device is applied to wind power generation and photovoltaic power generation because it integrates a variety of electrical equipment and provides an efficient and safe power control and protection solution.
[0003] The combined electrical apparatus in the related art, such as Figure 1 and Figure 2 shown, mainly includes an isolating switch and a circuit breaker. By controlling the opening and closing of the isolating switch and the circuit breaker, it is convenient to control the on-off of the transmission line in wind power generation and photovoltaic power generation. The safe and stable operation of the switching equipment in the combined electrical apparatus is directly related to the safety of the power grid and reliable power supply.
[0004] However, during the closing process of the circuit breaker in the combined electrical apparatus, the inrush current generated will impact equipment such as the load transformer. The inrush current generated by the combined electrical apparatus will cause the internal components of the equipment to bear excessive current, which may cause insulation damage and may also lead to the generation of electric arcs, resulting in the heating and even burning of the switch contacts. At the same time, the inrush current may cause voltage fluctuations, affect the normal operation of other equipment, and even trigger system failures. Summary of the Invention
[0005] In order to facilitate reducing the damage caused by the inrush current to equipment such as the load transformer in the transmission line, the present application provides a switching device dedicated for new energy power generation.
[0006] A switching device dedicated for new energy power generation provided by the present application adopts the following technical solutions:
[0007] A switching device dedicated for new energy power generation, the combined electrical apparatus includes an isolating switch QS, a first circuit breaker K1, a second circuit breaker K2, and a current-limiting element Z:
[0008] The outlet end of the isolating switch QS is connected to the inlet end of the first circuit breaker K1; the outlet end of the first circuit breaker K1 is connected to the inlet end of the second circuit breaker K2; the current-limiting element Z is connected in parallel to the second circuit breaker K2.
[0009] Optionally, the combined electrical apparatus further includes a frame. The isolating switch QS, the first circuit breaker K1, the second circuit breaker K2, and the current-limiting element Z are all installed on the frame, and the current-limiting element Z is located on the side of the second circuit breaker K2 away from the first circuit breaker K1.
[0010] Optionally, a support rod for supporting the current-limiting element Z is fixedly connected to the frame.
[0011] Optionally, a heat sink is installed on the current-limiting element Z.
[0012] Optionally, the heat sink is connected to the current-limiting element Z by bolts.
[0013] Optionally, a fixing member for fixing the heat sink is further provided on the current-limiting element Z. The fixing member includes two elastic clamping strips fixedly connected to the current-limiting element Z. The two elastic clamping strips are distributed on both sides of the heat sink and abut against the base of the heat sink.
[0014] In summary, the present application includes at least one of the following beneficial technical effects:
[0015] 1. When the combined electrical apparatus is put into operation in a photovoltaic power station and a wind power station, the combined electrical apparatus first controls the disconnector QS and the first circuit breaker K1 to be closed in sequence, so that the disconnector QS, the first circuit breaker K1, and the current-limiting element Z can be preferentially connected to the transmission line. At this time, under the limiting action of the current-limiting element Z, the current impact on the load transformer and other electrical equipment in the transmission line at the moment of closing is reduced, and further, the damage caused by the inrush current to equipment such as the load transformer in the transmission line is reduced. Further, after a delay of several time durations, the second circuit breaker K2 is closed, so that the load transformer and the load operate stably;
[0016] 2. The current-limiting element Z is indirectly fixed to the frame through the support rod, which is convenient for reducing the heat transfer between the current-limiting element Z and the second circuit breaker K2 and the first circuit breaker K1, and increasing the heat dissipation effect of the current-limiting element Z and the first circuit breaker K1 and the second circuit breaker K2. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 It is a schematic structural diagram of a combined electrical apparatus in the related art;
[0018] Figure 2 It is a side view of a combined electrical apparatus in the related art;
[0019] Figure 3 It is a circuit schematic diagram of a combined electrical apparatus provided in the first embodiment of the present application.
[0020] Figure 4 It is a side view of a combined electrical apparatus provided in the first embodiment of the present application;
[0021] Figure 5 It is a front view of a combined electrical apparatus provided in the first embodiment of the present application;
[0022] Figure 6Schematic diagram of the structure of a heat sink installed on a current-limiting component provided in the second embodiment of the present application.
[0023] Figure 7 Schematic diagram of the structure of a heat sink installed on a current-limiting component provided in the third embodiment of the present application.
[0024] Figure 8 Schematic diagram of the structure of an elastic clamping strip and a buckling strip provided in the third embodiment of the present application.
[0025] Explanation of reference numerals: 1, frame; 2, support rod; 3, heat sink; 4, fixing member; 5, elastic clamping strip; 6, buckling strip. Detailed implementation manners
[0026] The following further elaborates on the present application in conjunction with the attached Figure 3-8 drawings.
[0027] The embodiments of the present application disclose a special switch device for new energy power generation. The combined electrical apparatus for wind power generation and photovoltaic power generation is applied to the transmission lines of wind power generation and photovoltaic power generation. In other cases, such as conventional distribution lines, hydroelectric power transmission lines and other transmission lines, the combined electrical apparatus mentioned in the present application can also be used, so no further elaboration will be made here.
[0028] Embodiment 1:
[0029] As Figure 3 , Figure 4 and Figure 5 shown, the combined electrical apparatus includes an isolating switch QS, a first circuit breaker K1, a second circuit breaker K2 and a current-limiting component Z. The outgoing line end of the isolating switch QS is connected to the incoming line end of the first circuit breaker K1. The outgoing line end of the first circuit breaker K1 is connected to the incoming line end of the second circuit breaker K2. The current-limiting component Z is connected in parallel with the second circuit breaker K2, that is, the incoming line end of the current-limiting component Z is connected to the incoming line end of the second circuit breaker K2, and the outgoing line end of the current-limiting component Z is connected to the outgoing line end of the second circuit breaker K2. In the embodiments of the present application, both the first circuit breaker K1 and the second circuit breaker K2 are three-position circuit breakers, and the number of current-limiting components Z corresponds to the three-phase setting of the first circuit breaker K1 and the second circuit breaker K2.
[0030] In one possible implementation, the combined electrical apparatus may further include a current transformer, which is not shown in the present application Figure 4 and Figure 5 .
[0031] When a photovoltaic power station or a wind power station needs to be put into operation, control the isolating switch QS, the first circuit breaker K1, and the second circuit breaker K2 in the combined electrical apparatus to close in sequence. When the load transformer on the transmission line in a photovoltaic or wind power plant needs to be withdrawn or overhauled, control the second circuit breaker K2, the first circuit breaker K1, and the isolating switch QS in the combined electrical apparatus to open in sequence.
[0032] During the process of closing the isolating switch QS, circuit breaker one K1, and circuit breaker two K2 in sequence in the controlled combined electrical apparatus, the current-limiting element Z can be preferentially connected to the transmission line with the isolating switch QS and circuit breaker one K1. Thus, under the action of the current-limiting element Z, the inrush current during closing can be greatly reduced, and the impact on equipment such as load transformers on the transmission line can be minimized. Moreover, since the current-limiting element Z is preferentially connected to the transmission line relative to circuit breaker two K2, the inrush current during the switching process of the load transformer can be made relatively smooth. At the same time, by setting the program of the centralized control terminal in the combined electrical apparatus, circuit breaker two K2, circuit breaker one K1, and isolating switch QS are controlled to open in sequence, thereby reducing the no-load loss of the load transformers in the photovoltaic power station and the wind power station.
[0033] Specifically, when the load transformer in the transmission line is put into operation, first control the isolating switch QS to close, and then close circuit breaker one K1. At this time, the isolating switch QS, circuit breaker one K1, and current-limiting element Z form a path with the load transformer. The current-limiting element Z restricts the inrush current of the load transformer. After a delay of several time durations, then close circuit breaker two K2 to enable the load transformer and the load to operate stably. The delay of several time durations here can be set manually or can be set according to laboratory measurements.
[0034] When the load transformer in the transmission line needs to be withdrawn, first open circuit breaker two K2, and then open circuit breaker one K1. At this time, if only the load transformer is to be withdrawn, there is no need to open the isolating switch QS. If the load transformer is to be repaired, for the safety of maintenance personnel, then the isolating switch QS will be opened subsequently.
[0035] In this application, both circuit breaker one K1 and circuit breaker two K2 are independent circuit breakers with high mechanical life, and the current-limiting element Z is an inductive reactive current-limiting element Z with a characteristic low resistance value (resistance < 0.2 ohms).
[0036] As Figure 3 and Figure 4 shown, in this application, the combined electrical apparatus further includes a frame 1. Among them, the isolating switch QS, circuit breaker one K1, circuit breaker two K2, and current-limiting element Z are all fixed on the frame 1, and the current-limiting element Z and circuit breaker one K1 are distributed on both sides of circuit breaker two K2. Specifically, the current-limiting element Z is fixed on the top side of the frame 1.
[0037] A plurality of support rods 2 are fixedly connected to the frame 1. The number of support rods 2 corresponds to the number of current-limiting elements Z. The current-limiting elements Z are fixedly installed at the ends of the support rods 2 away from the frame 1, so as to facilitate fixing the current-limiting elements Z to the frame 1 through the support rods 2. At the same time, the current-limiting elements Z are indirectly fixed to the frame 1 through the support rods 2, which is convenient for reducing the heat transfer between the current-limiting elements Z and the circuit breakers K2 and K1, and increasing the heat dissipation effect of the current-limiting elements Z and the circuit breakers K1 and K2.
[0038] Embodiment 2:
[0039] As Figure 5 shown, in Embodiment 2 of the present application, on the top side of the current-limiting element Z, a heat sink 3 is fixedly installed by bolts. The heat sink 3 can accelerate the heat dissipation effect of the current-limiting element Z through heat conduction.
[0040] Embodiment 3:
[0041] As Figure 6 and Figure 7 shown, the difference between Embodiment 3 and Embodiment of the present application lies only in the way of fixing the heat sink 3. In Embodiment 3 of the present application, a fixing member 4 for fixing the heat sink 3 is provided on the top side of the current-limiting element Z.
[0042] The fixing member 4 includes two elastic clamping strips 5 and two buckling strips 6. The two elastic clamping strips 5 are both fixedly connected to the top side of the current-limiting element Z, and the two elastic clamping strips 5 are distributed on both sides of the heat sink 3 and abut against the base of the heat sink 3.
[0043] The two buckling strips 6 correspond to the two elastic clamping strips 5 one by one, and the buckling strips 6 and the elastic clamping strips 5 are integrally formed. The bottom sides of the two buckling strips 6 are both in contact with the base of the heat sink 3.
[0044] On the top side of each buckling strip 6, an inclined surface is provided, and the inclined surfaces on each buckling strip 6 are inclined downward along the vertical downward direction.
[0045] During the process of fixing the heat sink 3, on the one hand, the heat sink 3 can be pushed along the length direction of the two elastic clamping strips 5 to move, so that the base of the heat sink 3 moves between the two elastic clamping strips 5, and the heat sink 3 is fixed under the action of the two elastic clamping strips 5 and the two buckling strips 6.
[0046] On the other hand, it is possible to move the heat sink 3 along the vertically downward direction towards the side closer to the current-limiting element Z. At this time, the base of the heat sink 3 comes into contact with the inclined surface of the buckling strip 6, and under the action of the inclined surface of the buckling strip 6, the elastic clamping strip 5 bends away from the two sides of the heat sink 3 until the base of the heat sink 3 moves below the two buckling strips 6. At this time, due to the elastic action of the elastic clamping strip 5 itself, the elastic clamping strip 5 and the buckling strip 6 are reset, so the heat sink 3 is fixed under the action of the two elastic clamping strips 5 and the two buckling strips 6.
[0047] The implementation principle of the first embodiment of this application is as follows: During the process of sequentially closing the isolating switch QS, the first circuit breaker K1, and the second circuit breaker K2 in the controlled combined electrical appliance, the current-limiting element Z can be preferentially connected to the power transmission line with the isolating switch QS and the first circuit breaker K1. Thus, under the action of the current-limiting element Z, the impact of the closing inrush current on equipment such as the load transformer on the power transmission line can be greatly reduced. And because the current-limiting element Z is preferentially connected to the power transmission line relative to the second circuit breaker K2, the access current during the switching process of the load transformer can be made relatively smooth.
[0048] The above are all the preferred embodiments of this application. The protection scope of this application is not limited thereby. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.
[0049] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will all fall within the protection scope of the present invention.
Claims
1. A switch device for renewable energy power generation, characterized in that: The combined electrical equipment includes the isolating switch QS, the circuit breaker 1 K1, the circuit breaker 2 K2 and the current limiting element Z: The outlet terminal of the isolating knife switch QS is connected to the inlet terminal of the circuit breaker K1; the outlet terminal of the circuit breaker K1 is connected to the inlet terminal of the circuit breaker K2; the current limiting element Z is connected in parallel to the circuit breaker K2.
2. A switch device for renewable energy power generation according to claim 1, characterized in that: The combined electrical appliance also includes a frame (1), the isolating switch QS, the circuit breaker 1 K1, the circuit breaker 2 K2 and the current limiting element Z are all installed on the frame (1), and the current limiting element Z is located on a side of the circuit breaker 2 K2 away from the circuit breaker 1 K1.
3. A switch device for renewable energy power generation according to claim 2, characterized in that: A support rod (2) for supporting the current limiting element Z is fixedly connected to the frame (1).
4. A switch device for renewable energy power generation according to claim 3, characterized in that: The current limiting element Z is an inductive reactive current limiting element Z with a characteristic low resistance, wherein the resistance of the current limiting element Z is less than 0.2 ohms.
5. A switch device for renewable energy power generation according to claim 3, characterized in that: A heat sink (3) is installed on the current limiting element Z.
6. A switch device for renewable energy power generation according to claim 5, characterized in that: The heat sink (3) is connected to the current limiting element Z via bolts.
7. A switch device for renewable energy power generation according to claim 5, characterized in that: The current limiting element Z is also provided with a fixing member (4) for fixing the heat sink (3), and the fixing member (4) comprises two elastic clamping strips (5) fixedly connected to the current limiting element Z, and the two elastic clamping strips (5) are distributed on both sides of the heat sink (3) and abut against the base of the heat sink (3).
8. A switch device for renewable energy power generation according to claim 7, characterized in that: A buckle strip (6) is fixedly connected to the elastic clamping strip (5), the bottom side of the buckle strip (6) is in contact with the top side of the base of the heat sink (3), and the top side of the buckle strip (6) is provided with an inclined surface.