A new arithmetic coding system combining source channel coding and maximum a posteriori decoding were proposed. It combines source coding and error correction tasks into one unified process by introducing an adaptive ...A new arithmetic coding system combining source channel coding and maximum a posteriori decoding were proposed. It combines source coding and error correction tasks into one unified process by introducing an adaptive forbidden symbol. The proposed system achieves fixed length code words by adaptively adjusting the probability of the forbidden symbol and adding tail digits of variable length. The corresponding improved MAP decoding metric was derived. The proposed system can improve the performance. Simulations were performed on AWGN channels with various noise levels by using both hard and soft decision with BPSK modulation.The results show its performance is slightly better than that of our adaptive arithmetic error correcting coding system using a forbidden symbol.展开更多
为了弥补交流变速抽蓄机组涉网环节的不足,依据我国对大型发电机组并网的技术要求,提出了一种适用于交流变速抽蓄机组的单通道电力系统稳定器(power system stabilizer, PSS)设计方法,同时还给出了变速机组与定速机组的协同响应策略。...为了弥补交流变速抽蓄机组涉网环节的不足,依据我国对大型发电机组并网的技术要求,提出了一种适用于交流变速抽蓄机组的单通道电力系统稳定器(power system stabilizer, PSS)设计方法,同时还给出了变速机组与定速机组的协同响应策略。在励磁系统特性方面,对比分析了变速机组与定速机组的差异,改进了PSS的传递函数结构,提出了相关参数的估算方法,能够适应交流变速抽蓄机组的并网要求。在厂内协调方面,针对变速机组与定速机组的协同控制需求,研究了基于变模态分解技术的协同响应方案,并对比了抽蓄电厂的整体反应效果,能够用于指导首台变速机组投产的工程实际。为了进行仿真分析,搭建了IEEE 9节点系统,并利用真实风电场数据,构建了电网功率扰动场景,验证了所提方法的有效性。展开更多
基金The National Natural Science Foundation ofChina(No60332030)
文摘A new arithmetic coding system combining source channel coding and maximum a posteriori decoding were proposed. It combines source coding and error correction tasks into one unified process by introducing an adaptive forbidden symbol. The proposed system achieves fixed length code words by adaptively adjusting the probability of the forbidden symbol and adding tail digits of variable length. The corresponding improved MAP decoding metric was derived. The proposed system can improve the performance. Simulations were performed on AWGN channels with various noise levels by using both hard and soft decision with BPSK modulation.The results show its performance is slightly better than that of our adaptive arithmetic error correcting coding system using a forbidden symbol.
文摘为了弥补交流变速抽蓄机组涉网环节的不足,依据我国对大型发电机组并网的技术要求,提出了一种适用于交流变速抽蓄机组的单通道电力系统稳定器(power system stabilizer, PSS)设计方法,同时还给出了变速机组与定速机组的协同响应策略。在励磁系统特性方面,对比分析了变速机组与定速机组的差异,改进了PSS的传递函数结构,提出了相关参数的估算方法,能够适应交流变速抽蓄机组的并网要求。在厂内协调方面,针对变速机组与定速机组的协同控制需求,研究了基于变模态分解技术的协同响应方案,并对比了抽蓄电厂的整体反应效果,能够用于指导首台变速机组投产的工程实际。为了进行仿真分析,搭建了IEEE 9节点系统,并利用真实风电场数据,构建了电网功率扰动场景,验证了所提方法的有效性。
