下垂控制并网逆变器小信号稳定性分析

Stability Analysis of Droop Control of Grid-connected Inverter Based on Small-signal

微电网是将分布式能源整合到公共电网中的有效方法。其中最重要的问题是连接电网电压型逆变器中微电网的电力潮流控制。建立了并网逆变器功率流控制的小信号模型,可见,在传统的功率流控制中可能遭受弱阻尼和瞬态响应缓慢的问题,而提出新的改进下垂控制可减轻这些问题而不影响稳态潮流控制,同时降低微源间输出电压的幅值差,从而抑制无功环流的形成。TMS320F2812型数字信号处理器(DSP)实验系统分别验证了该方法的小信号模型分析和有效性。

Micro-grid is an effective way to integrate the distributed energy resources into the utility networks.One of the most important issue is the power flow control of grid-connected voltage-source inverter in micro-grid.The small- signal model of the power flow control for the grid-connected inverter is established ,from which it can be observed that the conventional power flow control may suffer from the poor damping and slow transient response.While the new improved droop control can mitigate these problems without affecting the steady-state power flow regulation to reduce the amplitude differences of the output voltage between the sources ,thus to suppress the reactive power circulation. Results of digital signal producer（DSP） TMS320F2812 verifies the small signal model analysis and efectiveness of the proposed method.