To ensure minimum line loss in a high⁃voltage DC ( HVDC ) transmission system for a multiterminal HVDC transmission system of meshed configuration, an optimal load distribution method based on modified droop control is presented in this paper. Average DC output voltage and output current of two neighboring converters are applied to the conventional droop control. At the same time using the low⁃bandwidth communication network, the DC bus voltage is improved and the optimal distribution of load power for different line impedance values is a⁃chieved. This study also analyzes the application of the control method using different line impedance values and communication delays. Simulation results show that the load distribution of the mesh multiterminal HVDC transmis⁃sion system is optimized under different conditions and achieves optimization and stability of the system. The pro⁃posed method maintains maximum values for DC output deviation within 5% of the rated voltage reference value, thus ensures line loss minimization of the network multiterminal HVDC system and improves the energy utilization efficiency.%为了确保高压直流输电系统中线路损耗达到最小，针对网状多端高压直流输电系统，提出了一种基于改进型下垂控制的负荷分配优化方法。该方法通过引入目标变换器相邻两台变换器的电压和电流信号，取其平均值为补偿分量投入到传统的下垂控制中，同时利用低带宽通信网络，实现直流母线电压的提升并实现了负荷功率在线路阻抗不同的情况下的最优分配。利用上述控制方法对线路阻抗的不同取值和通信延迟情况下的适用性进行了详细的分析。仿真结果表明：网状多端高压直流输电系统在不同情况下的最优化负荷分配，实现了系统的优化稳定运行。所提出的方法确保了直流输出偏差的最大值保持在额定电压参考值的5％以内，保证了网状多端高压直流输电系统的线路损耗最小化，提高了能源利用效率。
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