A method for calculating short circuit current of a vehicle multi-voltage level direct current power grid
By constructing a multi-voltage system power grid topology and using the superposition principle to calculate the short-circuit current of the vehicle's multi-voltage level DC power grid, the problem that existing technologies cannot calculate the short-circuit current of the vehicle's multi-voltage level DC power grid is solved, thus realizing the effectiveness and accuracy of short-circuit protection.
Patent Information
- Authority / Receiving Office
- CN Β· China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA NORTH VEHICLE RES INST
- Filing Date
- 2025-12-22
- Publication Date
- 2026-06-05
AI Technical Summary
Existing technologies cannot effectively calculate the short-circuit current of multi-voltage DC power grids in vehicles, resulting in the inability to provide accurate data support for short-circuit protection of vehicle DC power grid systems. Furthermore, the calculation methods used for land power grids and ship power systems are not applicable to multi-voltage DC power grids in vehicles.
By employing the superposition principle, a multi-voltage grid topology is constructed by determining the voltage system and load type, the location of the short-circuit point and the direction of current flow are determined, and the short-circuit current of each branch, including generators, batteries, supercapacitors and permanent magnet synchronous motors, is calculated. Combining the different operating modes of the DC-DC converter, the total short-circuit current value is calculated using the superposition principle.
It enables the calculation of short-circuit current for DC power grids of multiple voltage levels in vehicles, provides an effective basis for short-circuit protection, and enhances the safety and reliability of vehicle DC power grid systems.
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Figure CN122150697A_ABST