With the large-scale grid integration of new energy,virtual synchronous generator(VSG)control is supposed to be widely used.Aiming at the failure of traditional distance protection action under the existing VSG control,an improved VSG control strategy based on improving the adaptability of distance protection is proposed.Firstly,the mechanism of distance protection invalidation is analyzed.Then,with the reduction of current phase difference between the two sides of the fault point as control target,the active control of converter output fault current characteristics is realized by quantitatively designing the virtual impedance value in VSG inner loop control.Finally,the simulation model of short circuit fault when new energy grid is connected with AC line is built in Matlab/Simulink.The simulation results indicate that the proposed control strategy can effectively support the operational reliability of conventional distance protection.
关键词
新能源电力系统/距离保护/虚拟阻抗/虚拟同步发电机
Key words
renewable energy power system/distance protection/virtual impedance/virtual synchronous generator
维普
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