基于MMC平均值仿真模型的损耗快速评估方法  

Fast Loss Evaluation Method Based on MMC Average Simulation Model

作　　者：孙正东 郝全睿[1] SUN Zhengdong;HAO Quanrui(Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education(Shandong University),Jinan 250061,Shandong Province,China)

机构地区：[1]电网智能化调度与控制教育部重点实验室(山东大学),山东省济南市250061

出　　处：《中国电机工程学报》2024年第19期7739-7750,I0021,共13页PROCEEDINGS OF THE CHINESE SOCIETY FOR ELECTRICAL ENGINEERING

基　　金：国家电网有限公司科技项目(5108-202299261A-1-0-ZB)。

摘　　要：针对模块化多电平换流器(modular multilevel converter,MMC)损耗计算精度和速度难以兼顾的问题,提出一种MMC损耗快速在线评估方法。首先,基于确定的调制和电容电压平衡策略,构建开关频率曲面以反映任意稳态工况下的开关频率;其次,利用平均值模型计算开关频率上限和开关损耗功率上限;再次,结合计算结果和开关频率曲面,近似快速计算实际开关损耗,兼顾计算精度和计算效率;然后,考虑到损耗对仿真结果的影响,利用串联在桥臂上的受控电压源吸收的能量表征损耗,同时提出一种基于衰减函数的开关损耗注入方法,避免产生注入电压尖峰并改善注入效果。最后,在PSCAD中搭建计及损耗注入的MMC平均值仿真模型,验证所提方法的计算效率和准确性。To address the problem that the calculation accuracy and speed of MMC losses are difficult to balance,a fast online evaluation method of losses is proposed.First,based on the determined modulation and capacitor voltage balance strategy,the switching frequency surface is constructed to reflect the switching frequency under any steady-state working condition.Next,the upper limit of switching frequency and the upper limit of switching losses are calculated by using the average value model.Once again,combined with the calculation results and the switching frequency surface,the rapid calculation of the actual losses is realized with high accuracy.Then,considering the impact of losses on the simulation results,the energy absorbed by a controlled voltage source connected in series on the bridge arm is used to characterize the losses.A switching loss injection method based on attenuation function is proposed to avoid injection voltage spikes and improve injection efficiency.Finally,an MMC average simulation model considering loss injection is built in PSCAD to verify the computational efficiency and accuracy of the proposed method.

关 键 词：模块化多电平换流器 损耗计算 平均值模型 损耗注入 

分 类 号：TM711[电气工程—电力系统及自动化]