Abstract: A speaker having a support structure having a bracket, and a vibration structure having a bend ring. The bend ring comprises an arc portion and an outer brim connected to the bracket. The outer brim of the bend ring extends downwardly to abut and connect to an outer brim of the top of the bracket, and the outer brim of the bend ring does not exceed the outermost end of the arc portion in the radial direction. The effective vibration area of a speaker is increased by using the above structure, so that the sensitivity of the speaker is improved.

Abstract: A fast search method and system for cascading failures in hybrid AC/DC power systems. The fast search method for cascading failures in hybrid AC/DC power systems includes: Determining the initial failures and forming a failure set of the first-stage failure, setting the DC blocking or the failure level reaching the threshold as the search stop condition; Judge the cascading failures in the failure set of the current stage can trigger DC blocking, if a cascading failure can trigger DC blocking, store the DC blocking failure as the next-stage failure. Otherwise, cascading failures are searched on the AC side and the failure set of the next stage is determined based on the pruning search method and the outage risk value; If the search stop condition is satisfied, stop the search, otherwise, the number of failure stages is increased by one and return to judge the cascading failures to continue the search.

Abstract: A fast search method and system for cascading failures in hybrid AC/DC power systems. The fast search method for cascading failures in hybrid AC/DC power systems includes: Determining the initial failures and forming a failure set of the first-stage failure, setting the DC blocking or the failure level reaching the threshold as the search stop condition; Judge the cascading failures in the failure set of the current stage can trigger DC blocking, if a cascading failure can trigger DC blocking, store the DC blocking failure as the next-stage failure. Otherwise, cascading failures are searched on the AC side and the failure set of the next stage is determined based on the pruning search method and the outage risk value; If the search stop condition is satisfied, stop the search, otherwise, the number of failure stages is increased by one and return to judge the cascading failures to continue the search.