WO2017050189A1

WO2017050189A1 - Large-component igbt press fitting unit

Info

Publication number: WO2017050189A1
Application number: PCT/CN2016/099253
Authority: WO
Inventors: 魏晓光; 贺之渊; 张升; 王成昊; 刘远; 周万迪
Original assignee: 全球能源互联网研究院; 国家电网公司; 国网湖北省电力公司
Priority date: 2015-09-25
Filing date: 2016-09-18
Publication date: 2017-03-30
Also published as: CN105355603A; CN105355603B

Abstract

A large-component IGBT press fitting unit, comprising a support frame (14) and a press fitting unit that is located in the support frame (14) and is used for fixing an IGBT valve series. The press fitting unit comprises: press fitting stress cones (11) located at the two ends of the IGBT valve series, a pressure adaptive adjusting mechanism and an insulated isolation structure; and the press fitting stress cones (11) and the pressure adaptive adjusting mechanism are respectively and fixedly connected to metal end plates (01) arranged at the two ends of the support frame (14), and the insulated isolation structure is used for realizing electric isolation of the press fitting structure from electrical components.

Description

Large component IGBT press-fit unit

Technical field

The invention relates to the field of high voltage transmission, in particular to a large component IGBT press-fit unit.

Background technique

With the development of high-power power electronics technology, especially the development of high-voltage flexible DC transmission and flexible AC transmission, IGBT devices have become more and more widely used in power systems with their flexible and controllable shutdown characteristics. With the continuous increase of transmission capacity, IGBT devices with high withstand voltage, high flow capacity and large cross-section size are widely used. Early IGBT devices were mainly soldered. The device was designed with bolts fixed on the heat sink. The flow capacity and withstand voltage were limited, and the break mode was broken under the breakdown condition. The circuit device makes the design of this type of IGBT complex, limiting its extended application in the engineering field. In response to this problem, a new type of crimping IGBT has appeared in recent years, which is identical in electrical characteristics to the soldered IGBT, but the structure is completely different. The IGBT needs to be mounted on the heat dissipation structure by a certain pressure, and the device is in occur. In the case of breakdown, it is a short-circuit failure mode, similar to a thyristor. It does not need to be designed with a corresponding bypass device. It is easy to apply, has high reliability, and because of the press-fit design, the heat dissipation efficiency is higher, the junction temperature control is accurate, and there is more High withstand voltage and higher flow capacity.

This high-performance crimp IGBT is more demanding for press-fit. Therefore, the IGBT press-fit mechanism must have higher mechanical strength, better electrical insulation performance, and the compact structure is safe and reliable, and the performance is stable. For engineering applications, the IGBT press-fit mechanism should also facilitate press-fit and disassembly at the engineering site.

The design of the large component IGBT press-fit mechanism is similar to the thyristor press-fit. Basically, the method of applying pressure through the thyristor and the heat sink center line is adopted, but the implementation is various, and the press-fit frame structure of the IGBT press-fit mechanism is adopted. Diverse, pressure loading methods also have their own characteristics. At present, the more common reference thyristor press-fit frame is made of insulating laminated sheets and metal structural parts. A rigid frame composed of fastening bolts, although the structure is stable and strong, but the weight is large, relatively bulky, and the structure lacks elasticity, and the ability to adapt to the dimensional change of the IGBT press-fit mechanism is poor. The frequency converter on some electric power transfer locomotive equipment adopts the crimping type IGBT, and the press-fit mechanism adopts the press-fit frame with the metal structural member and the insulating tie rod, which is limited by the transverse shear strength limit of the insulating tie rod, and basically adopts the hoisting design. Very poor flexibility and low reliability. The pressure loading type of the IGBT press-fit mechanism also has various designs, and has a structure that is pressed by a single bolt center. This structure is inconvenient to install and repair, and the pressure control is inaccurate; there is also a structure by multi-screw pressing, this type The operation is complicated, the pressure loading is inconvenient, and it is difficult to ensure uniform pressure dispersion. For the crimp IGBT, since the thickness of the IGBT has a large deformation displacement due to the single device during press-fitting, it is inconvenient to press and disassemble. Up to now, there is no relevant large-component IGBT from the available literature. Reference technology route for adaptive design of press-fit pressure.

It is important to note that the domestically applied IGBT press-fit technology has not yet achieved a design patent for IGBT press-fit of 10 or higher levels at high voltage levels.

Summary of the invention

In order to remedy the above defects, the embodiment of the present invention provides a large component IGBT press-fit unit, which has the advantages of simple structure, uniform pressure dispersion, accurate press-fit, easy operation, and easy maintenance; and can solve the above problems in the prior art.

The object of the present invention is achieved by the following technical solutions:

A large component IGBT press-fit unit provided by the embodiment of the invention includes a support frame and a press-fit unit for fixing the IGBT valve string in the support frame;

The press-fit unit includes: a press-fit stress cone, a pressure adaptive adjustment mechanism, and an insulation isolation structure at both ends of the IGBT valve string;

The press-fit stress cone and the pressure adaptive adjustment mechanism are respectively fixed to the metal end plates at both ends of the support frame, and the insulation isolation structure is used for electrically isolating between the press-fit structure and the electrical component.

The beneficial effects achieved by the present invention are:

(1) The present invention is mainly directed to a DC power electronic device with a fully-controlled IGBT device as a core component of a flexible direct current transmission system, and is also applicable to an AC power transmission device with an IGBT device as a core component; the application range is wide and the applicability is strong;

(2) The design of the press-fit stress cone and the pressure adaptive mechanism proposed by the invention patent can ensure uniform dispersion and reliable press-fitting of the pressing force on the IGBT surface, and satisfy the reliable heat dissipation and uniform current carrying of the IGBT operation; The large components of multi-stage IGBT devices and heat sinks are pressed to ensure reliable electrical connection and effective heat dissipation of IGBT devices, ensuring reliable operation of IGBT devices under rated current or overload current;

(3) The support frame design of the metal end plate, the metal tie rod and the insulating sleeve combined by the invention patent can meet the structural stability and strength requirements of the IGBT press-fit unit, provide reliable support for the press-fit unit, and have high A compact insulation design is achieved with a potential difference;

(4) The arrangement form of the press-fit stress cone, the IGBT, the heat sink, the pressure self-adjusting mechanism, the disc spring and the like and the device combination proposed by the invention patent can realize the multi-stage IGBT large component press-fit of the IGBT press-fit unit, It can realize the crimping of IGBTs of up to 20 grades and above;

(5) The structure design of the IGBT heat sink proposed by the invention patent can realize the expansion of the function of the heat sink, and in addition to realizing the heat dissipation function of the IGBT, it also has the functions of fixed support IGBT drive and busbar connection;

(6) The design of the insulating spacer of the IGBT press-fit unit proposed by the invention patent can realize the potential isolation between the press-fit assembly of the IGBT and the heat sink and the support frame, and meet the requirements of air insulation and creepage distance. For the first time, the crimping IGBT has been fabricated in series with not less than 16 stages, and can be expanded to a maximum of 20 stages and above.

DRAWINGS

1 is a schematic structural view of a large component IGBT press-fit unit;

2 is a cross-sectional structural view of a large component IGBT press-fit unit;

Figure 3 is a schematic view showing the structure of a press-fit stress cone;

Figure 4 is a schematic view of the pressure dispersion principle of the press-fit stress cone;

Figure 5 is a IGBT press-fit unit support frame;

Figure 6 is a schematic view of the IGBT heat sink structure 1;

Figure 7 is a schematic view of the IGBT heat sink structure 2;

Figure 8 is a schematic view showing the structure of an insulating spacer.

Among them, 01-metal end plate, 02-metal tie rod, 03-insulation isolation disc, 04-insulation sleeve, 05-pressure adaptive cone head, 06-pressure adaptive cone, 07-dised spring, 08-heat sink 1,09-heat sink 2,10-IGBT,11-pressed stress cone,12-adjusting washer,13-pressure adapter,14-support frame,15-insulated support beam,16-first IGBT busbar fixed terminal , 17-drive fixed terminal, 18-first IGBT removal top pressure auxiliary terminal; 19-second IGBT busbar fixed terminal, 20-second IGBT removal top pressure auxiliary terminal, 21-heatsink limit terminal.

detailed description

The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

The invention relates to a large component IGBT press-fit unit design, which adopts a support fixed structure composed of a metal tie rod and a metal end plate as a carrier, and achieves pressure loading and uniform pressure dispersion by using a press-fit stress cone and a pressure adaptive adjustment mechanism; The combined disc spring mechanism realizes long-term pressure maintenance and deformation adaptive adjustment, and achieves high-potential isolation between the support structure and the IGBT through the insulating spacer disk. In order to ensure the long-term structural stability of the IGBT during operation and to avoid adverse effects on the IGBT performance caused by externally applied various impact loads, the press-fit unit is designed with an accurate centering mechanism to effectively protect the IGBT and meet its various operations. Working condition requirements.

As shown in FIG. 1 and FIG. 2, a large component IGBT press-fit unit provided by this embodiment includes a support frame 14 and a press-fit unit for fixing the IGBT valve string in the support frame;

Wherein, the press-fit unit comprises a press-fit stress cone 11 and a pressure adaptive adjustment mechanism at both ends of the IGBT valve string, and the press-fit stress cone and the pressure adaptive adjustment mechanism are respectively solidified with the metal end plate 01 at both ends of the support frame Pick up.

In order to ensure that the pressure is evenly dispersed on the IGBT press-fit surface, a special press-fit stress cone structure is designed using the "90-degree stress cone" theory. As shown in Fig. 3, the pressure is uniformly dispersed on the IGBT surface, and the dispersion principle is as follows. Figure 4 shows.

The press-fit stress cone has a solid funnel shape with a 90 degree angle between the tapered surfaces; a tapered head having an end face that is in close contact with one end of the IGBT valve string, and a cylindrical tail portion and a support frame The metal end plates 01 at one end are connected by a pressure adapter 13, and an adjusting spacer 12 sleeved on the cylindrical tail portion is mounted between the press-fit stress cone and the metal end plate.

The adjusting gasket is used to realize the compression deformation and the displacement gap filling during the IGBT press-fit process; the pressure loading terminal is used to cooperate with the external pressure loading mechanism to realize the transmission of the external pressure to the IGBT press-fit unit. The principle is:

The external pressure loading mechanism applies a pulling force to the pressure loading terminal, and the external pressure loading mechanism presses the pressure stress cone, and the external pressing force uniformly applies pressure to the IGBT and the heat sink through the press-fit stress cone, and gradually reaches the IGBT. The required rated press force. During the pressure loading process, the disc spring is gradually compressed and deformed, and a deformation gap is formed between the press-fit stress cone and the metal end plate, and the adjusting gasket matched with the gap is filled in between before the external pressing force is cancelled. Then, after the external pressing force is removed, the pressing force is maintained inside the IGBT press-fit unit by the disc spring deformation.

The pressure adaptive adjustment mechanism includes a pressure adaptive cone 05, a pressure adaptive cone 06 and a disc spring 07 disposed between the pressure adaptive cone and the metal end plate cone;

The disc spring 07 is used for realizing the pressure maintenance of the IGBT after the pressure loading and the deformation adjustment of the expansion and contraction of the IGBT and the heat sink assembly during the application process.

Through the cone matching of the pressure adaptive cone 05 and the pressure adaptive cone 06, the adaptive adjustment of the shape and position deviation caused by the dimensional tolerance of the IGBT, the heat sink and the auxiliary structure during the pressure loading process is realized, and the pressing force of the IGBT is ensured. Uniform distribution to meet IGBT heat dissipation and flow requirements.

As shown in Figure 5, the support frame includes two metal end plates 01 and four gold fixed by nuts. The utility model belongs to the pull rod 02; the bottom end of the two metal end plates is provided with an insulating support beam 15 for supporting the IGBT valve string, and the four corners of each metal end plate are respectively provided with through holes for the metal rods to pass through, and between the four metal rods A space for accommodating the IGBT valve string is left, and the metal tie rod is externally sheathed with an insulating sleeve 04. The insulating support beam is used for the fixed support of the IGBT valve string and the device before the IGBT press-fit unit is pressed, and also serves as the IGBT valve string support after the IGBT is disassembled and the press-fit force is cancelled.

In order to maintain the air insulation distance requirement between the support frame and the IGBT, the heat sink and other metal structural parts inside the IGBT press-fit unit under a high potential difference, an insulating spacer disk is arranged between the end surface of the tapered head and the IGBT valve string. 03.

The insulating spacer disk is made of high-strength insulating material, and is designed as an umbrella structure from the open end to the middle part of the disc, and the disc structure is adopted as a whole, and is connected with the press-fit stress cone.

Among them, the insulating spacer disk is made of high-strength insulating material as shown in Fig. 8. The crawler umbrella group is distributed from the lower end to the middle of the disc; the disc structure is connected with the press-fit stress cone. With this design, single-potential isolation of the support frame can be achieved.

In order to have good heat dissipation performance, the outermost ends of the IGBT valve string are heat sinks, which simplifies the structural integration design of the IGBT press-fit unit application equipment, and is advantageous for the compact design of the application equipment.

The IGBT valve string is composed of a heat sink and an IGBT 10 which are connected in series, and the IGBT has the same structure of the 08 heat sink 1 or the same structure of the 09 heat sink 2, or one side of the IGBT is the heat sink 1, and the other The side is the heat sink 2. The IGBT heat sink and the IGBT are alternately distributed, and the two conductive contact faces of each IGBT are bonded to the heat sink to realize bidirectional heat dissipation of the IGBT.

As shown in FIG. 6 and FIG. 7, the heat sink 1 includes: a first IGBT busbar fixed terminal 16, a driving fixed terminal 17, and a first IGBT detachment pressing auxiliary terminal 18; the first IGBT busbar fixed terminal and The driving fixed terminals are respectively disposed on the left and right sides of the heat sink 1; the IGBT detaching pressing auxiliary terminal is located at the top of the heat sink 1;

The 09 heat sink 2 includes: a second IGBT busbar fixed terminal 19, and a second IGBT disassembly The top auxiliary terminal 20 and the heat sink limit terminal 21; the second IGBT busbar fixed terminal and the second IGBT dismounting auxiliary terminal are respectively disposed on the left and right sides of the heat sink 2, and the heat sink limit The terminal is located at the top of the heat sink 2.

It should be noted that the above embodiments are only used to explain the technical solutions of the present application and not to limit the scope of the protection thereof. Although the present application is described in detail with reference to the above embodiments, those skilled in the art should understand that: A person skilled in the art can still make various changes, modifications, or equivalents to the specific embodiments of the application after reading the present application. These changes, modifications, or equivalents are all within the scope of the claims to be approved.

Claims

A large component IGBT press-fit unit includes a support frame and a press-fit unit for fixing the IGBT valve string in the support frame;

The press-fit unit includes: a press-fit stress cone, a pressure adaptive adjustment mechanism, and an insulation isolation structure at both ends of the IGBT valve string;

The press-fit stress cone and the pressure adaptive adjustment mechanism are respectively fixed to the metal end plates at both ends of the support frame, and the insulation isolation structure is used for electrically isolating between the press-fit structure and the electrical component.
The press-fit unit according to claim 1, wherein the press-fit stress cone has a solid funnel shape with a 90 degree angle between the tapered surfaces, and has a tapered head portion and a cylindrical tail portion;

An end surface of the tapered head of the press-fit stress cone is in close contact with one end of the IGBT valve string; and an insulating spacer disk is disposed between the end surface of the tapered head and the IGBT valve string;

The cylindrical tail portion of the press-fit stress cone is sleeved with an adjustment pad; the cylindrical tail portion is connected to the metal end plate at one end of the support frame through a pressure adapter.
The press-fit unit according to claim 2, wherein said insulating spacer is made of a high-strength insulating material, and a crawler umbrella group is distributed from the lower end to the middle of the disc, and the disc structure and the press-fit stress are used. The cones are connected to each other.
The press-fit unit of claim 1, wherein the pressure adaptive adjustment mechanism comprises: a disc spring disposed between the pressure adaptive cone and the metal end plate for achieving pressure after pressure loading Maintain and adjust the deformation of the application process.
The press-fit unit of claim 4, wherein the pressure adaptive adjustment mechanism further comprises: a pressure adaptive cone and a pressure adaptive cone; the pressure adaptive cone and the pressure adaptation The tapered surface of the cone is matched to realize the adaptive adjustment of the shape and position deviation caused by the dimensional tolerance of the IGBT, the heat sink and the auxiliary structure during the pressure loading process.
The press-fit unit according to claim 1, wherein: said support frame comprises two metal end plates and four metal tie rods fixed by nuts;

Therefore, the bottom end of the metal end plate is provided with an insulating support beam for supporting the IGBT valve string, and the four corners of each metal end plate are respectively provided with through holes for the metal rod to pass through;

A space for accommodating the IGBT valve string is left between the adjacent two metal tie rods, and the metal tie rod is externally sheathed with an insulating sleeve.
The press-fit unit according to claim 1, wherein said IGBT valve string is composed of a heat sink and an IGBT spaced apart in series;

A heat sink 1 having the same structure is used on both sides of the IGBT, or a heat sink 2 having the same structure is used, or one side of the IGBT is a heat sink 1 and the other side is a heat sink 2 .
The press-fit unit according to claim 7, wherein the heat sink 1 comprises: a first IGBT busbar fixed terminal, a drive fixed terminal, and a first IGBT detachment pressing auxiliary terminal;

The first IGBT busbar fixed terminal and the driving fixed terminal are respectively disposed on the left and right sides of the heat sink 1. The IGBT detachment pressing auxiliary terminal is located at the top of the heat sink 1.
The press-fit unit according to claim 7, wherein the heat sink 2 comprises: a second IGBT busbar fixed terminal, a second IGBT detachment pressing auxiliary terminal, and a heat sink limit terminal;

The second IGBT busbar fixed terminal and the second IGBT detachment pressing auxiliary terminal are respectively disposed on the left and right sides of the heat sink 2. The heat sink limit terminal is located at the top of the heat sink 2.