Current limit control can protect converters from overcurrent damage during fault transient but may simultaneously deteriorate the transient synchronization stability.This paper focuses on the transient stability anal...Current limit control can protect converters from overcurrent damage during fault transient but may simultaneously deteriorate the transient synchronization stability.This paper focuses on the transient stability analysis and enhancement of the grid-forming renewable energy system integrated via a voltage source converter based high-voltage direct current(VSC-HVDC)link,considering current limit.First,the switched dynamic model of the studied system under current limit is developed.It is found that switching between voltage control mode and current restricted control mode occurs when the power angle difference between the renewable energy inverter and the VSC-HVDC rectifierreaches a specificvalue.Accordingly,the transient stability mechanism of the studied system is analyzed using the system's power-angle curve,and the transient stability criterion is derived from the segmented equal-area criterion.On this basis,an optimal tuning strategy for the saturation current angle is further proposed to enhance the transient stability of the system.Simulation results verify the accuracy of the derived stability criterion and the effectiveness of the proposed parameter-tuning strategy.展开更多
The change of the over-current protection point of the power switches, caused by slope compensation, is analyzed in detail. It is discovered that the peak current protecting value increases as the duty cycle decreases...The change of the over-current protection point of the power switches, caused by slope compensation, is analyzed in detail. It is discovered that the peak current protecting value increases as the duty cycle decreases. As a result, the safety operation of the switches is damaged greatly. A novel solution to improve over-current protection with constant peak current limitation is proposed by inducing synchronous slope compensation into the current limit function instead of the original constant voltage. The design principle and method of the protection circuit based on a UC3846 PWM controller for the interleaved dual-forward converter is presented. Experimental results are given to verify the analysis.展开更多
基金supported in part by the National Natural Science Foundation of China(No.52507144)in part by The Shaanxi Provincial Natural Science Foundation funds research projects in basic scientificareas(2025JC-YBQN-593)+1 种基金in part by the Science and Technology Development Fund(001/2024/SKL)the State Key Laboratory of Internet of Things for Smart City(University of Macao,China)Open Research Project(Ref.No.:SKL-IoTSC(UM)/ORP06/2026).
文摘Current limit control can protect converters from overcurrent damage during fault transient but may simultaneously deteriorate the transient synchronization stability.This paper focuses on the transient stability analysis and enhancement of the grid-forming renewable energy system integrated via a voltage source converter based high-voltage direct current(VSC-HVDC)link,considering current limit.First,the switched dynamic model of the studied system under current limit is developed.It is found that switching between voltage control mode and current restricted control mode occurs when the power angle difference between the renewable energy inverter and the VSC-HVDC rectifierreaches a specificvalue.Accordingly,the transient stability mechanism of the studied system is analyzed using the system's power-angle curve,and the transient stability criterion is derived from the segmented equal-area criterion.On this basis,an optimal tuning strategy for the saturation current angle is further proposed to enhance the transient stability of the system.Simulation results verify the accuracy of the derived stability criterion and the effectiveness of the proposed parameter-tuning strategy.
文摘The change of the over-current protection point of the power switches, caused by slope compensation, is analyzed in detail. It is discovered that the peak current protecting value increases as the duty cycle decreases. As a result, the safety operation of the switches is damaged greatly. A novel solution to improve over-current protection with constant peak current limitation is proposed by inducing synchronous slope compensation into the current limit function instead of the original constant voltage. The design principle and method of the protection circuit based on a UC3846 PWM controller for the interleaved dual-forward converter is presented. Experimental results are given to verify the analysis.
