Overload protection device for core-changing type film capacitor

Abstract

The invention provides a core-changing type thin film capacitor overload protection device, and relates to the technical field of automobile thin film capacitors, the core-changing type thin film capacitor overload protection device comprises an overload protection core which is arranged in a capacitor shell and / or connected to the capacitor shell, the overload protection core is connected with a capacitor core in parallel, and the overload voltage of the overload protection core is lower than that of the capacitor core. The overload protection core connected with the capacitor core in parallel is arranged, and the overload voltage of the overload protection core is lower than that of the capacitor core, so that the capacitor core can be effectively protected. The overload protection core part is externally arranged and is easy to damage, an easy breakdown point is located on the overload protection core, when the overload protection core breaks down or is damaged, the normal function of the capacitor can be repaired by replacing the overload protection core, the whole capacitor does not need to be replaced, and the problem that a capacitor core is not easy to maintain and replace when being damaged in the prior art is solved.

Description

Technical Field

[0001] The invention relates to the technical field of automobile film capacitors, and in particular to an overload protection device for a core-replaceable film capacitor. Background Art

[0002] In the motor controller of new energy vehicles, film capacitors, as key components, play an important role in removing high-frequency harmonic signal interference in the power supply, storing electrical energy, and protecting circuits. Film capacitors usually use polypropylene film as the insulating medium and are made through processes such as metal evaporation, winding, hot pressing, gold spraying, welding and capping. During the capping process, the capacitor core is encapsulated in the capacitor shell with epoxy resin. However, in the actual working process, due to the influence of high temperature, high ripple current and other working conditions, the internal film of the capacitor core will experience overload phenomena such as breakdown.

[0003] Since the capacitor core is encapsulated inside the capacitor, it is not convenient for daily maintenance and replacement; and the existing film capacitors do not have an overload protection device for the capacitor core. Therefore, once the internal film of the capacitor core is broken down or there is an overload, it will affect the performance stability and service life of the capacitor.

[0004] In view of this, how to provide a film capacitor that is easy to replace the capacitor core and has an overload protection device for the capacitor core is a problem that technical personnel in this field urgently need to solve. Summary of the invention

[0005] The purpose of the present invention is to provide a core-replaceable film capacitor overload protection device to solve the problems existing in the prior art.

[0006] To achieve the above object, the present invention provides the following solution: The present invention provides a core-changeable film capacitor overload protection device, wherein the capacitor core is encapsulated in a capacitor housing, comprising:

[0007] The overload protection core is arranged in the capacitor housing and / or connected to the capacitor housing. The overload protection core is connected in parallel with the capacitor core, and its overload voltage is lower than the overload voltage of the capacitor core.

[0008] Furthermore, the capacitor housing is provided with a mounting hole through the inner and outer surfaces, and the overload protection core is detachably disposed in the mounting hole.

[0009] Furthermore, the overload protection core portion is located outside the capacitor housing.

[0010] Furthermore, it also includes:

[0011] The overload protection core is electrically connected to the busbar through contacts, the busbar is electrically connected to the capacitor core, and the overload protection core forms a parallel circuit with the capacitor core through the busbar.

[0012] Furthermore, it also includes:

[0013] A mounting seat, one end of which is fixedly connected to the upper edge and / or the lower edge of the mounting hole, and the other end of which extends into the capacitor housing, and the contact is arranged on the mounting seat.

[0014] The present invention discloses the following technical effects:

[0015] 1. The present application is provided with an overload protection core connected in parallel with the capacitor core. The overload voltage of the overload protection core is lower than that of the capacitor core, and can effectively protect the capacitor core.

[0016] 2. The overload protection core is partially external, and the vulnerable and breakdown points are located on the overload protection core. When the overload protection core is broken down or damaged, the normal function of the capacitor can be restored by replacing the overload protection core without replacing the entire capacitor, thus overcoming the problem of the existing technology that the capacitor core is damaged and difficult to maintain and replace. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic diagram of the structure of the present invention;

[0019] Figure 2 for Figure 1 Schematic diagram of the structure after removing the capacitor casing;

[0020] Figure 3 for Figure 2 Schematic diagram of the bottom structure;

[0021] Figure 4 It is a schematic diagram of the capacitor housing structure;

[0022] Among them, 1. capacitor housing; 101. mounting hole; 2. capacitor core; 3. overload protection core; 4. mounting seat; 5. contact; 6. upper busbar; 7. lower busbar. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0025] Example 1

[0026] An embodiment of the present invention discloses an overload protection device for a core-replaceable film capacitor, wherein a capacitor core 2 is encapsulated in a capacitor housing 1, and comprises: an overload protection core 3, which is arranged on the capacitor housing 1 in a semi-enclosed manner, and the overload protection core 3 is connected in parallel with the capacitor core 2, and its overload voltage is lower than the overload voltage of the capacitor core 2.

[0027] The capacitor housing 1 is provided with mounting holes 101 through the inner and outer surfaces, and the overload protection core 3 is detachably arranged in the mounting hole 101. A portion of the overload protection core 3 is located outside the capacitor housing 1, and another portion is located inside the capacitor housing 1. The overload protection core 3 located inside the capacitor housing 1 is electrically connected to the busbar through the contact 5, and the busbar is electrically connected to the capacitor core 2. The overload protection core 3 forms a parallel circuit with the capacitor core 2 through the busbar.

[0028] The mounting seat 4 includes an upper mounting seat 4 and a lower mounting seat 4, the upper mounting seat 4 is fixedly connected to the upper edge of the mounting hole 101, the lower mounting seat 4 is fixedly connected to the lower edge of the mounting hole 101, the upper mounting seat 4 is provided with an upper contact 5, the lower mounting seat 4 is provided with a lower contact 5, the overload protection core 3 is fixed on the mounting seat 4 by a detachable connection form such as a snap connection, and its upper and lower ends are electrically connected to the upper contact 5 and the lower contact 5 respectively. There are two groups of busbars, one group of busbars is electrically connected to the upper contact 5 and the upper end of the capacitor core 2, and the other group of busbars is electrically connected to the lower contact 5 and the lower end of the capacitor core 2. Each group of busbars is composed of an upper busbar 6 and a lower busbar 7 connected to each other.

[0029] Example 2

[0030] The difference between this embodiment and embodiment 1 is that the capacitor core 2 is composed of a metal layer and an insulating medium, and the thickness of the metal layer and the insulating medium is increased to enhance the dielectric strength, reduce local discharge, and improve the reliability and stability of the capacitor.

[0031] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply 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 understood as a limitation on the present invention.

[0032] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A core-replaceable film capacitor overload protection device, wherein a capacitor core (2) is encapsulated in a capacitor housing (1), characterized in that: include: The overload protection core (3) is arranged in the capacitor housing (1) and / or connected to the capacitor housing (1); the overload protection core (3) is connected in parallel with the capacitor core (2), and its overload voltage is lower than the overload voltage of the capacitor core (2).

2. The overload protection device for a core-replaceable film capacitor according to claim 1, characterized in that: The capacitor housing (1) is provided with a mounting hole (101) penetrating the inner and outer surfaces, and the overload protection core (3) is detachably arranged in the mounting hole (101).

3. The overload protection device for a core-replaceable film capacitor according to claim 2, characterized in that: The overload protection core (3) is partially located outside the capacitor housing (1).

4. The overload protection device for a core-replaceable film capacitor according to claim 3 is characterized in that: Also includes: The overload protection core (3) is electrically connected to the busbar via a contact (5), the busbar is electrically connected to the capacitor core (2), and the overload protection core (3) forms a parallel circuit with the capacitor core (2) via the busbar.

5. The overload protection device for a core-replaceable film capacitor according to claim 4, characterized in that: Also includes: A mounting seat (4), one end of the mounting seat (4) is fixedly connected to the upper edge and / or the lower edge of the mounting hole (101), and the other end extends into the capacitor housing (1); the contact (5) is arranged on the mounting seat (4).

Images