Inter-regional transmission line fault often results in power flow transferring, tie-line overloading and system islanding. Traditional control methods such asgenerator tripping and load shedding are costly, and also ...Inter-regional transmission line fault often results in power flow transferring, tie-line overloading and system islanding. Traditional control methods such asgenerator tripping and load shedding are costly, and also have undesirable impacts on theloadside. In this paper, a new emergency power control strategy is proposed for multi-channel interconnected system by using the overload capacity of non-fault DC lines. First of all, the capacity of emergency power control can be acquired by critical transmission power of a certain tie-line for stability. Secondly, the shortest electric distance can be calculated by Dijkstra algorithm, and then the priority of emergency control of the DC lines can be obtained by the entropy weight method. When the inter-regional transmission power decreases and the effect of single DC line emergency control is poor, the multi-channel cooperative emergency control strategy is proposed to ensure the system stability. Simulation results verify the effectiveness of the method proposed.展开更多
针对大范围降噪的传统多通道主动噪声控制(multi-channel active noise control, MANC)系统计算复杂、降噪性能差且缺乏可扩展性的问题,提出了一种基于扩散协作方法的低复杂度分布式主动噪声控制(distributed active noise control, DA...针对大范围降噪的传统多通道主动噪声控制(multi-channel active noise control, MANC)系统计算复杂、降噪性能差且缺乏可扩展性的问题,提出了一种基于扩散协作方法的低复杂度分布式主动噪声控制(distributed active noise control, DANC)系统。该DANC系统开发了一种扩散滤波x最小均方(diffusion filter-x least mean square, DFxLMS)算法。提出的DFxLMS-DANC方案使用次级路径约束,以减少计算开销。仿真结果表明,在4个节点的情况下与基于多误差FxLMS的MANC系统相比,所提出DFxLMS-DANC计算乘法和加法数量分别减少42%和4.6%,所提出的算法在实际的空调噪声环境下仍然可以达到更好的降噪性能。展开更多
由于风电互联系统结构复杂并且具有随机性,传统控制器难以满足系统多运行方式下的阻尼控制效果,为提高含风电互联系统抑制低频振荡的能力,提出静止无功补偿器(static var compensator,SVC)附加双通道广域阻尼控制方法。首先建立附加双...由于风电互联系统结构复杂并且具有随机性,传统控制器难以满足系统多运行方式下的阻尼控制效果,为提高含风电互联系统抑制低频振荡的能力,提出静止无功补偿器(static var compensator,SVC)附加双通道广域阻尼控制方法。首先建立附加双通道控制器模型;其次基于频域子空间辨识与几何测度结合法设计最佳控制回路,实测方便,更有利于应用在复杂电网;最后采用基于多目标函数的改进型鸟群算法(improved bird swarm algorithm,IBSA)对控制器进行优化,确定控制参数。将上述研究方法通过含风电的两区四机系统进行仿真验证,结果表明接入设计控制器的系统阻尼大大提高,控制效果显著,能够快速抑制振荡,从而增强系统稳定性能。展开更多
Ad Hoc网络分层结构中,媒体接入控制(MAC)协议规定了节点共享有限的无线带宽资源,直接影响到Ad Hoc网络的总体性能。介绍了各类MAC协议,以及影响协议性能的关键技术。同时分析了这些关键技术应用于各类MAC协议的优缺点,提出了关键技术...Ad Hoc网络分层结构中,媒体接入控制(MAC)协议规定了节点共享有限的无线带宽资源,直接影响到Ad Hoc网络的总体性能。介绍了各类MAC协议,以及影响协议性能的关键技术。同时分析了这些关键技术应用于各类MAC协议的优缺点,提出了关键技术在工程应用中应当遵循的规则和条件,有助于专用MAC协议研究与设计。展开更多
文摘Inter-regional transmission line fault often results in power flow transferring, tie-line overloading and system islanding. Traditional control methods such asgenerator tripping and load shedding are costly, and also have undesirable impacts on theloadside. In this paper, a new emergency power control strategy is proposed for multi-channel interconnected system by using the overload capacity of non-fault DC lines. First of all, the capacity of emergency power control can be acquired by critical transmission power of a certain tie-line for stability. Secondly, the shortest electric distance can be calculated by Dijkstra algorithm, and then the priority of emergency control of the DC lines can be obtained by the entropy weight method. When the inter-regional transmission power decreases and the effect of single DC line emergency control is poor, the multi-channel cooperative emergency control strategy is proposed to ensure the system stability. Simulation results verify the effectiveness of the method proposed.
文摘针对大范围降噪的传统多通道主动噪声控制(multi-channel active noise control, MANC)系统计算复杂、降噪性能差且缺乏可扩展性的问题,提出了一种基于扩散协作方法的低复杂度分布式主动噪声控制(distributed active noise control, DANC)系统。该DANC系统开发了一种扩散滤波x最小均方(diffusion filter-x least mean square, DFxLMS)算法。提出的DFxLMS-DANC方案使用次级路径约束,以减少计算开销。仿真结果表明,在4个节点的情况下与基于多误差FxLMS的MANC系统相比,所提出DFxLMS-DANC计算乘法和加法数量分别减少42%和4.6%,所提出的算法在实际的空调噪声环境下仍然可以达到更好的降噪性能。