Voltage source converters(VSCs),equipped with Pf and Q-U droop characteristics,can support a power system from both frequency and voltage.Unfortunately,overcurrent and power angle instability are still challenging asp...Voltage source converters(VSCs),equipped with Pf and Q-U droop characteristics,can support a power system from both frequency and voltage.Unfortunately,overcurrent and power angle instability are still challenging aspects of VSCs under fault conditions.Therefore,fault current limitation and power angle stability are essential conditions for the safe operation of a VSC.Thus,the transient characteristics of a VSC are analyzed to guide transient control.Then,a transient control method for a VSC,considering both fault current limitation and power angle stability,is proposed.With the proposed method,power angle stability is realized by optimizing the P-f controller.On the basis of power angle control,the Q-U controller and inner current controller are improved to effectively suppress the fault current.Finally,relevant tests are performed to verify the proposed method.展开更多
基金supported in part by the National Natural Science Foundation of China(51907057 and 52077072)Technological Leading Talent of Hunan province(2019RS3014).
文摘Voltage source converters(VSCs),equipped with Pf and Q-U droop characteristics,can support a power system from both frequency and voltage.Unfortunately,overcurrent and power angle instability are still challenging aspects of VSCs under fault conditions.Therefore,fault current limitation and power angle stability are essential conditions for the safe operation of a VSC.Thus,the transient characteristics of a VSC are analyzed to guide transient control.Then,a transient control method for a VSC,considering both fault current limitation and power angle stability,is proposed.With the proposed method,power angle stability is realized by optimizing the P-f controller.On the basis of power angle control,the Q-U controller and inner current controller are improved to effectively suppress the fault current.Finally,relevant tests are performed to verify the proposed method.