1. 浙江大学电气工程学院, 浙江省杭州市 310027; 2. 国网福建省电力有限公司福州供电公司, 福建省福州市 350009; 3. 北京理工大学自动化学院, 北京市 100081
1. College of Electrical Engineering, Zhejiang University, Hangzhou 310027, China; 2. Fuzhou Power Supply Company of State Grid Fujian Electric Power Company, Fuzhou 350009, China; 3. School of Automation, Beijing Institute of Technology, Beijing 100081, China
The detailed analysis of loss characteristics for converter is of great importance for system design and cooling device selection. This paper analyzes and calculates the loss distribution of submodule and the total loss of converter based on the working characteristics of full bridge submodules in hexagonal modular multilevel AC/AC converter(Hexverter). Firstly, the operation principle of Hexverter is briefly introduced and simulated. Secondly, the on-state and switching characteristics of insulated gate bipolar translator(IGBT)and freewheel diode are established by fitting the data of IGBT module. The working conditions of submodule are analyzed in detail. According to the output characteristics of full bridge submodule, the analytical expressions of conduction range and the time of each device are derived, respectively. Then the theoretical analysis expressions of conduction loss and switching loss are obtained. Finally, the loss of the converter is quantificationally analyzed in 10 kV system, the loss distribution of different submodules is calculated, and the losses of Hexverter in different working conditions are calculated. The results show that the loss distribution in full bridge submodule is symmetrical, and the loss of each submodule in one branch is not the same. Additionally, the loss distribution of submodules and the total loss of the converter are obviously different, especially in various working conditions of different capacities and power factors.
ZHANG Chong, LI Kuanhong, ZHANG Xuan,et al.Analysis and Calculation of Loss Characteristics for Hexagonal Modular Multilevel AC/AC Converter[J].Automation of Electric Power Systems,2019,43(13):105-113. DOI:10.7500/AEPS20180620005.