中文摘要：

直流输电技术的快速发展迫切要求提出实用的交直流混合状态估计方法。该文将交流系统看成主系统，将直流系统看成从系统，提出了交直流混合状态估计的一种新方法，即主从分裂法。该方法自然地将整个电力网络的状态估计问题分解成交流估计和直流估计两个子问题，通过主从分裂迭代，可获得严格的全局状态估计解。其中，交流系统和直流系统可以采用不同的状态估计算法，只需对调度中心现有状态估计软件进行少量修改，即可实现交直流混合状态估计。理论分析和数值试验结果均表明了新方法的实用性、正确性和良好的收敛性。

英文摘要：

With rapid development of HVDC technologies, development of practical methods for AC/DC hybrid power system state estimation is an emergent demand. In the whole AC/DC hybrid power system, AC part is considered as master system, while DC part is considered as slave system in the paper. Then a new method named as master-slave-splitting is proposed for AC/DC hybrid power system state estimation. In the new method, the problem of state estimation for whole power system is naturally split into two sub questions, one is AC system estimation and the other is DC system estimation. Based upon master-slave- splitting iteration, rigorous solution of the whole AC/DC hybrid power system state estimation can be achieved, and different algorithms are adopted for estimation of AC and DC systems respectively. The new method can be implemented in existed state estimation module in control center with minor modification of software. Both theoretical analysis and numerical tests verify practicability, validity and convergence of new method.