Series-parallel connection waterway structure applied to alternating current circuit breaker and circuit breaker

Abstract

A series-parallel connection waterway structure applied to an alternating current circuit breaker is installed in a main loop of the alternating current circuit breaker and comprises a first main pipe, a second main pipe, a first unit water pipe, a second unit water pipe and a radiator connecting pipe. Wherein the first main pipe and the second main pipe are arranged in parallel and are respectively connected with the water machine; the alternating-current circuit breaker main loop comprises diode strings and IGCT strings, a plurality of radiators are arranged on the alternating-current circuit breaker main loop, and the diode strings are symmetrically arranged on the two sides of the IGCT strings; the first main pipe is connected with the first unit water pipe, the first unit water pipe and the second unit water pipe are respectively connected with the radiators, the radiators are connected through the radiator connecting pipes, and the second unit water pipe is connected with the second main pipe. The alternating current circuit breaker adopts a water cooling mode to dissipate heat of the power device, so that the use performance of the power device and the reliability of the system can be ensured. The series-parallel heat dissipation mode can uniformize the temperature of the radiator, reduces the requirement for the water flow speed in the radiator, and can save part of space in the aspect of structural design.

Description

Technical Field

[0001] The utility model belongs to the field of power equipment, and particularly relates to a series - parallel water circuit structure and a circuit breaker applied to an AC circuit breaker. Background Art

[0002] With the rapid development of power semiconductor devices, the application scenarios of solid - state circuit breakers based on power electronic devices are becoming more and more extensive. The core components of a solid - state circuit breaker are power modules composed of IGCT transistors and fast - recovery diodes. These two power electronic devices are also the main components that generate heat loss in the system. When the accumulated heat exceeds the maximum allowable junction temperature, the performance of the power module will be affected, and further the reliability of the system will be affected. Therefore, it is crucial to ensure the heat dissipation of power devices so that their temperatures are lower than the maximum junction temperature.

[0003] With the continuous expansion of the scale of the power system, the requirements for the safe and stable operation of the power system are getting higher and higher. A circuit breaker is an essential device in the power system, which can perform the operation of interrupting abnormal current in the circuit in a short time, prevent the further expansion of abnormal states, and maintain the safe and stable operation of the power system.

[0004] In the power system, the conventionally used circuit breaker is a mechanical circuit breaker, with a response speed in the millisecond level. It is easy to generate arcs during the breaking process and has poor environmental adaptability. With the development of power semiconductor devices, solid - state circuit breakers based on power electronic devices have developed rapidly. Compared with traditional mechanical circuit breakers, solid - state circuit breakers have the advantages of fast response speed, no arc generation during the breaking process, and strong environmental adaptability.

[0005] A solid - state circuit breaker is mainly composed of turn - off devices such as IGBT and IGCT and diodes. Such power electronic devices will generate losses during operation, and the generated losses will be dissipated to the outside in the form of heat. Due to the limitation of the volume of the device, natural cooling heat dissipation cannot meet the normal operation requirements of the device. As the temperature rises, the normal operation of power electronic devices such as IGBT, IGCT, and diodes will be affected, thereby reducing the reliability of the system. Currently, most of the cooling methods used are water - cooled heat dissipation.

[0006] Currently, the design of the internal water circuit of solid - state circuit breakers is relatively single. It does not consider that the more power electronic devices the water circuit passes through, the temperature of the liquid inside the water circuit will gradually increase through heat exchange. The heat exchange effect on the power electronic devices at the end of the water circuit is not ideal, and there will be a phenomenon of uneven heat dissipation of different power electronic devices, which will affect the performance of solid - state circuit breakers. Summary of the Utility Model

[0007] To solve the deficiencies existing in the prior art, the present utility model provides a series-parallel water circuit structure and a circuit breaker applied to an AC circuit breaker.

[0008] The technical solution of the present utility model is as follows.

[0009] In the first aspect of the present utility model, a series-parallel water circuit structure applied to an AC circuit breaker is provided, which is installed in the main circuit of the AC circuit breaker:

[0010] It includes a first main pipe, a second main pipe, a first unit water pipe, a second unit water pipe, and a radiator connection pipe; wherein, the first main pipe and the second main pipe are arranged in parallel, and both are respectively connected to a water machine;

[0011] The main circuit of the AC circuit breaker includes a plurality of valve strings, namely a diode string and an IGCT string. The diode string is symmetrically arranged on both sides of the IGCT string, and a plurality of radiators are respectively arranged on each valve string;

[0012] The number of the first unit water pipes, the second unit water pipes, and the radiator connection pipes is multiple;

[0013] The first main pipe is connected to the first unit water pipe, the first unit water pipe and the second unit water pipe are respectively connected to the radiator, and the plurality of radiators are connected by the radiator connection pipe, and the second unit water pipe is connected to the second main pipe.

[0014] Preferably, the radiators between the diode string and the IGCT string are connected in series through the radiator connection pipe.

[0015] Preferably, within a single valve string of the diode string and the IGCT string, the upper and lower adjacent radiators are connected in series through the radiator connection pipe.

[0016] Preferably, within a single valve string of the diode string and the IGCT string, the total number of radiators is odd, and the remaining one radiator is separately connected in series by one path.

[0017] Preferably, the first unit water pipes are arranged in parallel and connected to the first main pipe in parallel;

[0018] The second unit water pipes are arranged in parallel and connected to the second main pipe in parallel.

[0019] Preferably, the first main pipe is the inlet main pipe, and the second main pipe is the outlet main pipe;

[0020] The first unit water pipe is the inlet unit pipe, and the second unit water pipe is the outlet unit pipe.

[0021] Preferably, the first main pipe is the outlet main pipe, and the second main pipe is the inlet main pipe;

[0022] The first unit water pipe is the outlet unit pipe, and the second unit water pipe is the inlet unit pipe.

[0023] Preferably, joints are installed at both ends of the first unit water pipe, the second unit water pipe, and the radiator connecting pipe.

[0024] Water nozzles for connecting with the first unit water pipe and the second unit water pipe are fixedly installed on the first main pipe and the second main pipe.

[0025] Preferably, equipotential water needles are arranged at the bottoms of the first main pipe and the second main pipe.

[0026] The second aspect of the present utility model provides an AC circuit breaker:

[0027] In the main circuit of the AC circuit breaker, a series-parallel water circuit structure applied to the AC circuit breaker as described above is installed.

[0028] The beneficial effects of the present utility model are as follows. Compared with the prior art:

[0029] 1. The present utility model provides a more effective water-cooling heat dissipation circuit for a solid-state circuit breaker. The entire circuit adopts a series-parallel form. Through the series form, the power electronic devices that need to dissipate heat in each path are connected in series, and the types and quantities of the power electronic devices selected in each series branch are the same. The heat dissipation amounts of each series circuit are in a consistent state. At the same time, the series connection method can make the water circuit path of each group of devices that need to dissipate heat reach the shortest.

[0030] 2. The present utility model provides a more effective water-cooling heat dissipation circuit for a solid-state circuit breaker. The entire circuit adopts a series-parallel form. The water inlets of each series branch are connected in parallel through the parallel form to obtain the total water inlet, and the water outlets of each series branch are connected in parallel through the parallel form to obtain the total water outlet. Through the parallel connection of the water circuits, the overall heat dissipation amount is dispersed to each branch, so that the total heat dissipation amount can be evenly distributed, avoiding local overheating.

[0031] 3. The present utility model provides a solid-state circuit breaker with a compact structure. The valve string structure of the solid-state circuit breaker is compact. The power electronic devices and the radiator are pressed onto a valve string by a crimping method. Radiators are provided on both the upper and lower surfaces of each power electronic device, which better improves the heat dissipation efficiency of the power electronic devices. The diode string and the IGCT string are placed side by side, and the structure is more compact, saving the overall space of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present utility model will be further described below with reference to the drawings.

[0033] Figure 1 It is a schematic diagram of the series-parallel water circuit structure applied to the AC circuit breaker of the present utility model.

[0034] In the drawings, the corresponding relationships between the reference numerals and the component names are as follows:

[0035] 1 - First main pipe, 2 - Second main pipe, 3 - First unit water pipe, 4 - Second unit water pipe, 5 - Radiator connecting pipe, 6 - Diode string, 7 - IGCT string, 8 - Equipotential water needle. Specific embodiments

[0036] To make the objectives, technical solutions and advantages of the present utility model clearer, the technical solutions of the present utility model will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present utility model. The embodiments described in this application are only a part of the embodiments of the present utility model, rather than all embodiments. Based on the spirit of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0037] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present utility model.

[0038] Embodiment 1 of the present utility model provides a series-parallel waterway structure applied to an AC circuit breaker. The series-parallel waterway pipes are installed in the main circuit of the AC circuit breaker. The main circuit of the AC circuit breaker includes 3 valve strings, namely two diode strings 6 and one IGCT string 7. The two diode strings 6 are symmetrically arranged on the left and right sides of the IGCT string. There are n radiators arranged on the diode string 6, where n is a natural number, and there are m radiators arranged on the IGCT string 7, where m is a natural number.

[0039] The series-parallel waterway structure applied to an AC circuit breaker provided by an embodiment of the present utility model includes: a first main pipe 1, a second main pipe 2, a first unit water pipe 3, a second unit water pipe 4, and a radiator connecting pipe 5. There is one first main pipe 1 and one second main pipe 2 respectively. The number of the first unit water pipes 3 and the second unit water pipes 4 is at least 1, and the number of the radiator connecting pipes 5 is at least 2. The numbers of the first unit water pipes 3, the second unit water pipes 4, and the radiator connecting pipes 5 vary according to the number of radiators in the valve string. The first main pipe 1 is connected to the first unit water pipe 3, the first unit water pipe 3 is connected to the second unit water pipe 4 through the radiator connecting pipe 5, and the second unit water pipe 4 is connected to the second main pipe 2. The radiator connecting pipe 5 is used to connect the radiators of the AC circuit breaker diode string 6 and the IGCT string 7.

[0040] Taking every two adjacent radiators up and down in each valve string as a group, one first unit water pipe 3 and one second unit water pipe 4 are arranged for each group of radiators on the diode strings at both ends. The radiator connecting pipe 5 is used for series connection between each group of radiators and between the radiators of adjacent valve strings. The first unit water pipes 3 of each group of radiators on the diode strings at both ends are connected in parallel to the first main pipe 1, and the second unit water pipes 4 of each group of radiators are connected in parallel to the second main pipe 2.

[0041] The present utility model takes every two adjacent radiators up and down in each valve string as a group as a preferred but non-limiting embodiment, and does not limit the structure that cannot use a single radiator, three radiators or more as a group. By adopting the structure of taking every two adjacent radiators up and down in each valve string as a group, the waterway can be utilized more effectively. There are power electronic devices between every two adjacent radiators up and down in each valve string, and the heat generated by these devices can be fully dissipated through the waterway. In the way of taking every two adjacent radiators up and down in each valve string as a group, the number of parallel branches on the first main pipe (1) is the same as the usage amount of IGCT devices, and the devices passing through each branch are the same, which can ensure that the heat dissipation amount of each branch is the same. If the total number of radiators in the valve string is odd, the last remaining radiator in each valve string is connected in series alone by a single path. The flowing direction of the cooling water in the waterway can be changed. The first main pipe 1, the second main pipe 2, the first unit water pipe 3, and the second unit water pipe 4 can be used as both the water inlet pipe and the water outlet pipe, and equal-potential water needles 8 are arranged at the bottoms of the first main pipe 1 and the second main pipe 2 to equalize the potentials of the cooling water at the water inlet and the water outlet. The equal-potential water needles can keep the potential of the liquid inside the waterway at this position consistent with the potential of a certain point in the main circuit, avoiding the phenomenon of electrochemical corrosion due to potential difference.

[0042] Water pipe joints are installed at both ends of each first unit water pipe 3 and the second unit water pipe 4 for installation and fixation with the radiator, the first main pipe 1, and the second main pipe 2. Joints are installed at both ends of each radiator connecting pipe 5 for installation and fixation with the radiator. Water nozzles are installed on each first main pipe 1 and the second main pipe 2 for connection with the unit inlet and outlet water pipes.

[0043] Embodiment 2 of the present utility model provides an AC circuit breaker. The main circuit of the AC circuit breaker includes two diode strings 6 and an IGCT string 7. The above-mentioned series-parallel water circuit structure applied to the AC circuit breaker is installed in the main circuit of the AC circuit breaker.

[0044] The beneficial effects of the present utility model are as follows. Compared with the prior art,

[0045] 1. The present utility model provides a more effective water-cooling heat dissipation circuit for a solid-state circuit breaker. The entire circuit adopts a series-parallel form. Through the series form, the power electronic devices that need to dissipate heat in each path are connected in series, and the types and quantities of the power electronic devices selected for each series branch are the same. The heat dissipation amounts of each series loop are in a consistent state. At the same time, the series connection method can make the water circuit path of each group of devices that need to dissipate heat reach the shortest.

[0046] 2. The present utility model provides a more effective water-cooling heat dissipation circuit for a solid-state circuit breaker. The entire circuit adopts a series-parallel form. The water inlets of each series branch are connected in parallel to obtain the total water inlet through the parallel form, and the water outlets of each series branch are connected in parallel to obtain the total water outlet through the parallel form. Through the parallel connection of the water circuits, the overall heat dissipation amount is dispersed to each branch, so that the total heat dissipation amount can be evenly distributed, avoiding local overheating.

[0047] 3. The present utility model provides a solid-state circuit breaker with a compact structure. The valve string structure of the solid-state circuit breaker is compact. The power electronic devices and radiators are pressed onto a valve string by a pressing method. Radiators are provided on the upper and lower surfaces of each power electronic device, which better improves the heat dissipation efficiency of the power electronic devices. The diode string and the IGCT string are placed side by side, and the structure is more compact, saving the overall space of the device.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model and are not intended to limit them. Although the present utility model has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: the specific implementation manners of the present utility model can still be modified or equivalently replaced, and any modification or equivalent replacement that does not depart from the spirit and scope of the present utility model should be covered within the protection scope of the claims of the present utility model.

Claims

1. A series-parallel water circuit structure applied to an AC circuit breaker, installed in the main circuit of the AC circuit breaker, characterized in that: It comprises a first mother pipe (1), a second mother pipe (2), a first unit water pipe (3), a second unit water pipe (4) and a radiator connecting pipe (5); wherein the first mother pipe (1) and the second mother pipe (2) are arranged in parallel, and both are connected to a water machine respectively; The main circuit of the AC circuit breaker comprises a plurality of valve strings, which are respectively a diode string (6) and an IGCT string (7), wherein the diode string (6) is symmetrically arranged on both sides of the IGCT string (7), and each valve string is respectively provided with a plurality of heat sinks; There are multiple first unit water pipes (3), second unit water pipes (4) and radiator connecting pipes; The first mother pipe (1) is connected to the first unit water pipe (3), the first unit water pipe (3) and the second unit water pipe (4) are respectively connected to the radiator, the plurality of radiators are connected via the radiator connecting pipe (5), and the second unit water pipe (4) is connected to the second mother pipe (2).

2. The series-parallel water channel structure applied to AC circuit breaker according to claim 1, characterized in that: The radiators between the diode string (6) and the IGCT string (7) are connected in series via a radiator connecting pipe (5).

3. The series-parallel water channel structure applied to AC circuit breaker according to claim 1, characterized in that: In a single valve string of a diode string (6) and an IGCT string (7), two upper and lower adjacent radiators are connected in series via a radiator connecting pipe (5).

4. The series-parallel water channel structure applied to AC circuit breaker according to claim 3, characterized in that: In a single valve string of a diode string (6) and an IGCT string (7), the total number of radiators is an odd number, and the remaining radiator is connected in series using a single connection.

5. The series-parallel water channel structure applied to AC circuit breaker according to claim 1, characterized in that: The first unit water pipes (3) are arranged in parallel and connected to the first mother pipe (1) in parallel; The second unit water pipes (4) are arranged in parallel and connected to the second mother pipe (2) in parallel.

6. The series-parallel water channel structure applied to AC circuit breaker according to claim 1, characterized in that: The first mother pipe (1) is a water inlet mother pipe, and the second mother pipe (2) is a water outlet mother pipe; The first unit water pipe (3) is a water inlet unit pipe, and the second unit water pipe (4) is a water outlet unit pipe.

7. The series-parallel water channel structure applied to AC circuit breaker according to claim 1, characterized in that: The first mother pipe (1) is a water outlet mother pipe, and the second mother pipe (2) is a water inlet mother pipe; The first unit water pipe (3) is a water outlet unit pipe, and the second unit water pipe (4) is a water inlet unit pipe.

8. The series-parallel water channel structure applied to AC circuit breaker according to claim 1, characterized in that: Joints are installed at both ends of the first unit water pipe (3), the second unit water pipe (4) and the radiator connecting pipe (5); Water nozzles for connecting to the first unit water pipe (3) and the second unit water pipe (4) are fixedly installed on the first mother pipe (1) and the second mother pipe (2).

9. The series-parallel water channel structure applied to AC circuit breaker according to claim 1, characterized in that: Equipotential water needles (8) are arranged at the bottom of the first mother pipe (1) and the second mother pipe (2).

10. An AC circuit breaker, characterized in that: The series-parallel water channel structure applied to the AC circuit breaker as claimed in any one of claims 1 to 9 is installed in the main circuit of the AC circuit breaker.

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