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CN-122020962-A - Design method of high-safety connection module

CN122020962ACN 122020962 ACN122020962 ACN 122020962ACN-122020962-A

Abstract

The invention discloses a design method of a high-safety connecting module, which relates to the technical field of power electronics and comprises a connecting module, wherein the connecting module is arranged between a power module, a direct-current power supply and a film capacitor, at least one group of protection circuits are integrated in the connecting module, each group of protection circuits corresponds to an independent bridge arm in the power module and is used for cutting off the connection between the protection circuits and the direct-current power supply when the bridge arm fails, each group of protection circuits comprises a high-speed switching device and is used for rapidly cutting off the connection between the protection circuits and the positive electrode and the negative electrode of the direct-current power supply when the corresponding bridge arm fails, connecting terminals for laser welding are arranged at two ends of the connecting module, the copper terminal is made of the same material as the terminal material of the power module and the aluminum terminal is made of the same material as the terminal material of the film capacitor, so that the laser welding between different materials is compatible, and the problem of mismatching of laser welding materials in the customer production process is effectively solved.

Inventors

  • YANG YAO

Assignees

  • 九章晶格(上海)科技有限公司

Dates

Publication Date
20260512
Application Date
20251224

Claims (7)

  1. 1. The design method of the high-safety connecting module is characterized by designing a high-safety connecting module, wherein the high-safety connecting module comprises connecting modules (U-1, U-3), and the connecting modules (U-1, U-3) are arranged between a power module (U-2) and a direct current power supply and a thin film capacitor; At least one group of protection circuits are integrated in the connecting modules (U-1, U-3), and each group of protection circuits corresponds to an independent bridge arm in the power module (U-2) and is used for cutting off the connection between the bridge arm and a direct current power supply when the bridge arm fails; Each group of protection circuits comprises a high-speed switching device and is used for rapidly cutting off the connection between the high-speed switching device and the positive electrode and the negative electrode of the direct-current power supply when the corresponding bridge arm fails; Connecting terminals for laser welding are arranged at two ends of the connecting module, each connecting terminal comprises a copper terminal (P-1) and an aluminum terminal (P-5), the material of the copper terminal (P-1) is the same as the material of the terminal of the power module (U-2), the material of the copper terminal is the same as the material of the aluminum terminal (P-5) and the material of the terminal of the thin film capacitor, and the connecting terminals are convenient for being compatible with laser welding among different materials.
  2. 2. The method of claim 1, wherein the protection circuit comprises a positive protection circuit and a negative protection circuit; The positive electrode protection circuit comprises a battery positive electrode connecting terminal (P-10) connected with the battery positive electrode, a power module positive electrode connecting terminal (P-11) connected with the power module positive electrode and a high-speed switching device connected in series, wherein a circuit formed by the battery positive electrode connecting terminal (P-10) to the power module positive electrode connecting terminal (P-11) is used for protecting the power module positive electrode and is responsible for cutting off the positive electrode connection; The negative electrode protection loop comprises a battery negative electrode connection section (P-9) connected with a battery negative electrode, a power module negative electrode connection terminal (P-8) connected with a power module negative electrode and a high-speed switch device connected in series, and the loop formed from the power module negative electrode connection terminal (P-8) to the battery negative electrode connection section (P-9) is used for protecting the power module negative electrode and is responsible for cutting off the negative electrode connection.
  3. 3. The method of claim 2, wherein the positive protection circuit and the negative protection circuit are stacked to cancel magnetic fields and reduce stray inductances introduced into the system.
  4. 4. The method for designing the high-safety connection module according to claim 1, wherein the package structure of the connection module (U-1, U-3) comprises a ceramic copper clad laminate DBC (P-2), an epoxy resin (P-3) and a signal terminal (P-4); The ceramic copper clad laminate DBC (P-2) is used as a carrier and an electrical insulation layer of the high-speed switch device; epoxy resin (P-3) for molding to form a module outer envelope; and a signal terminal (P-4) for receiving external control and detection signals.
  5. 5. The method for designing a high-safety connection module according to claim 4, wherein the package structure is a double-sided heat dissipation structure, an internal power loop of the package structure is connected with the copper sheet (P-7) by a Clip welding process, and insulation and support are realized by an insulation Spacer (P-6).
  6. 6. A method of designing a high-safety connection module according to claim 1, characterized in that the power module (U-2) is a large half-bridge module consisting of 3 separate small half-bridges.
  7. 7. A method of designing a high-safety connection module according to claim 1, characterized in that the connection modules (U-1, U-3) can be packaged as a single module or a plurality of the protection circuits required for one inverter can be packaged in the same module.

Description

Design method of high-safety connection module Technical Field The invention relates to the technical field of power electronics, in particular to a high-safety connection module design method. Background In current power module applications, it is common for the power terminals of the power module to be directly connected to the membrane capacitor without the high-security connection module described herein. If one or more chips in the power module fail, the controller will be stopped directly due to the failure, and unpredictable risks will occur for the system functions. For example, in the field of automobile application, in a high-speed running state of an automobile, sudden abnormality leads to no power output of the automobile, and great potential safety hazards exist. The current module application system design, the power module is mainly connected to the membrane capacitor in four modes, namely terminal laser welding, bolt connection, soldering and spring lamination crimping. The high-current application environment mainly adopts two modes of terminal laser welding and bolt connection at present. The terminal laser welding is adopted, so that the terminal laser welding is suitable for application scenes with high current and high switching frequency, but the required equipment and process cost is increased along with the increase of the size of the device terminal, and meanwhile, the terminal laser welding has requirements on the material of the device terminal, and the current use cost is high; The adoption of the bolt connection is influenced by a contact interface at the bolt connection position, so that larger contact resistance exists, and larger parasitic inductance exists at the same time, and the output current and the switching frequency of the module are limited to a great extent although the production difficulty is low. Disclosure of Invention The invention aims to solve the technical problem that a high-safety connecting module design method is provided for overcoming the defect that a high-reliability connecting piece is not available in the module application in the prior art, and the problem that laser welding cannot be completed due to different materials of a power module and a film capacitor terminal is effectively solved. The invention adopts the following technical scheme for solving the technical problems: the design method of the high-safety connecting module designs a high-safety connecting module, wherein the high-safety connecting module comprises a connecting module, and the connecting module is arranged between a power module, a direct-current power supply and a thin film capacitor; At least one group of protection circuits are integrated in the connection module, and each group of protection circuits corresponds to one independent bridge arm in the power module and is used for cutting off the connection between the bridge arm and a direct current power supply when the bridge arm fails; Each group of protection circuits comprises a high-speed switching device and is used for rapidly cutting off the connection between the high-speed switching device and the positive electrode and the negative electrode of the direct-current power supply when the corresponding bridge arm fails; the connecting module is characterized in that connecting terminals for laser welding are arranged at two ends of the connecting module, the connecting terminals comprise copper terminals and aluminum terminals, the materials of the copper terminals are the same as the terminal materials of the power module, the materials of the copper terminals and the aluminum terminals are the same as the terminal materials of the thin film capacitor, and the connecting terminals are convenient to be compatible with laser welding among different materials. As a further preferable scheme of the design method of the high-safety connecting module, the protection circuit comprises an anode protection circuit and a cathode protection circuit; The positive electrode protection circuit comprises a battery positive electrode connecting terminal connected with a battery positive electrode, a power module positive electrode connecting terminal connected with a power module positive electrode and a high-speed switch device connected in series, wherein a circuit formed by the battery positive electrode connecting terminal and the power module positive electrode connecting terminal is used for protecting the power module positive electrode and is responsible for cutting off positive electrode connection; The negative electrode protection loop comprises a battery negative electrode connecting section for connecting a battery negative electrode, a power module negative electrode connecting terminal for connecting a power module negative electrode and a high-speed switch device connected in series, wherein the loop formed by the power module negative electrode connecting terminal and the battery negative electrode connecting se