Abstract: Disclosed in the present application are a self-energy-taking hybrid direct-current circuit breaker and an application method therefor. In the self-energy-taking hybrid direct-current circuit breaker, a breaking branch is connected to a through-current branch in parallel, a first end of a grounding branch is connected to the breaking branch, and a second end of the grounding branch is grounded. When a direct-current system operates stably, the through-current branch conducts a steady-state running current of the direct-current system, and when the direct-current system breaks down, a self-energy-taking capacitor in the breaking branch assists a power electronic device in achieving the breaking of a fault current.

Abstract: A federated learning method includes: obtaining a target federated sub-model of a target participating node, the target federated sub-model being obtained upon dividing up a federated model, the federated model comprising at least three federated sub-models, and the target federated sub-model comprising a model parameter and a target feature of the target participating node; obtaining a current network delay and preset instances of optimization of the target feature; determining current instances of optimization on the basis of the difference between the current network delay and a preset network delay corresponding to the preset instances of optimization; performing local optimization on the target feature according to the current instances of optimization; and performing encrypted interaction of an optimization result of the target feature with other participating nodes, so as to optimize a model parameter and determine a target model parameter of the target federated sub-model.

Abstract: Provided in the present disclosure are an IGBT device backside structure and a preparation method therefor, and an IGBT device, the IGBT device backside structure comprising a buffer layer, the buffer layer comprising a first activation efficiency buffer area corresponding to an active area of the IGBT device and a second activation efficiency buffer area corresponding to a terminal area of the IGBT device, the activation efficiency of the first activation efficiency buffer area being less than the activation efficiency of the second activation efficiency buffer area.