基于混合式直流断路器(hybrid direct current circuit breaker,HDCCB)保护的柔性直流电网在故障清除之后,需要对故障线路进行快速重合闸操作。在直流系统被孤立的换流站重合闸于故障清除状态的故障恢复期间,会有较大的功率波动导致重...基于混合式直流断路器(hybrid direct current circuit breaker,HDCCB)保护的柔性直流电网在故障清除之后,需要对故障线路进行快速重合闸操作。在直流系统被孤立的换流站重合闸于故障清除状态的故障恢复期间,会有较大的功率波动导致重合闸过程中功率恢复缓慢,不能满足直流电网快速重合闸的要求。该文首先基于HDCCB的拓扑结构提出重合闸操作时间最短的快速重合闸操作流程。然后基于直流电网的控制系统,从直流电网的故障开断过程出发,揭示了在直流电网重合闸过程中功率波动的原因,并且提出了优化之后的快速重合闸策略,以实现直流系统重合闸于故障清除状态时功率的快速恢复。利用电磁暂态仿真软件PSCAD/EMTDC搭建5端柔直系统进行仿真,结果表明所提出的快速重合闸策略能够有效地抑制孤立换流站在重合闸于故障清除状态时故障恢复过程中的功率波动,缩短重合闸恢复时间50%以上,提高直流系统的输电可靠性。展开更多
This paper deals with non-autonomous fractional stochastic reaction-diffusion equations driven by multiplicative noise with s∈(0,1).We first present some conditions for estimating the boundedness of fractal dimension...This paper deals with non-autonomous fractional stochastic reaction-diffusion equations driven by multiplicative noise with s∈(0,1).We first present some conditions for estimating the boundedness of fractal dimension of a random invariant set.Then we establish the existence and uniqueness of tempered pullback random attractors.Finally,the finiteness of fractal dimension of the random attractors is proved.展开更多
文摘基于混合式直流断路器(hybrid direct current circuit breaker,HDCCB)保护的柔性直流电网在故障清除之后,需要对故障线路进行快速重合闸操作。在直流系统被孤立的换流站重合闸于故障清除状态的故障恢复期间,会有较大的功率波动导致重合闸过程中功率恢复缓慢,不能满足直流电网快速重合闸的要求。该文首先基于HDCCB的拓扑结构提出重合闸操作时间最短的快速重合闸操作流程。然后基于直流电网的控制系统,从直流电网的故障开断过程出发,揭示了在直流电网重合闸过程中功率波动的原因,并且提出了优化之后的快速重合闸策略,以实现直流系统重合闸于故障清除状态时功率的快速恢复。利用电磁暂态仿真软件PSCAD/EMTDC搭建5端柔直系统进行仿真,结果表明所提出的快速重合闸策略能够有效地抑制孤立换流站在重合闸于故障清除状态时故障恢复过程中的功率波动,缩短重合闸恢复时间50%以上,提高直流系统的输电可靠性。
基金The authors would like to thank the reviewers for their helpful comments.This work was partially supported by the National Natural Science Foundation of China(11871138)joint research project of Laurent Mathematics Center of Sichuan Normal UniversityNational-Local Joint Engineering Laboratory of System Credibility Automatic Verification,funding of V.C.&V.R.Key Lab of Sichuan Province.
文摘This paper deals with non-autonomous fractional stochastic reaction-diffusion equations driven by multiplicative noise with s∈(0,1).We first present some conditions for estimating the boundedness of fractal dimension of a random invariant set.Then we establish the existence and uniqueness of tempered pullback random attractors.Finally,the finiteness of fractal dimension of the random attractors is proved.
