虚拟同步发电机接口变换器并联运行虚拟阻抗自适应控制

Adaptive Control of Virtual Impedance in Parallel Operation of Virtual Synchronous Generator Interface Converter

随着虚拟同步发电机(VSG)技术在微网以及主动配电网中应用的增多,VSG接口变换器并联运行越来越广泛,其中的环流和功率分配不精确问题也成为研究重点。该文首先引入虚拟阻抗,分析两台VSG接口变换器并联运行的功率均分原则。其次针对传统虚拟阻抗算法无法对线路阻抗进行调节的缺陷,设计一种虚拟阻抗自适应的算法,同时给出参数取值依据,实时计算线路两端的阻抗值,自适应虚拟阻抗可自动平衡线路之间的差异,更好地解决VSG接口变换器并联运行的功率均分问题。最后对VSG接口变换器并联运行的各种工况进行Matlab/Simulink仿真验证,证明了所提出的算法的有效性与正确性。

With the increasing in the application of virtual synchronous generator(VSG)technology in micro grid and active distribution network,VSG interface converters operating in parallel are more and more widely.So the problem of equalization in the division had naturally became the focus of research.In this paper,the virtual impedance was introduced at first.Then,taking two VSGs as an example,the principle of equalization of two parallel operations was analyzed.The traditional virtual impedance algorithm cannot adjust the line impedance.A virtual impedance adaptive algorithm was designed.The value of the line impedance will be calculated in real time,and the adaptive virtual impedance can automatically balance the impedance differences of each line,and solved the problem of accurate distribution.At the same time,the setting parameters were given.Finally,Matlab/simulink simulation was carried out under various working conditions to prove the validity and correctness of the proposed algorithm.