【摘要】 在多微源组网的独立微网中,采用传统的虚拟同步发电机(VSG)控制可在一定程度上改善系统的惯性和频率特性,为进一步优化频率和功率的暂态响应特性,提出一种基于频率偏差积分补偿的VSG控制策略。该控制策略将频率的变化量经积分后补偿到一阶虚拟惯性环节的前向通道上,以减小因负载扰动对系统产生的功率冲击,从而抑制功率和频率振荡,保证了输出功率稳态控制精度,加快了动态功率和频率的响应速度并防止其振幅变化过快。同时,在有功频率控制环节中保留一次调频系数,使得系统的稳态调频特性得以保留。在此还通过建立组网逆变器的小信号模型进一步探讨了不同的虚拟惯量和阻尼系数对系统暂态响应的影响,并提供了虚拟惯量和阻尼系数的设定方案和整定方法。最后,利用Matlab/Simulink和dSPACE平台验证了所提控制策略的有效性。结果表明,基于频率偏差积分补偿的VSG控制策略,在改善系统暂态响应特性方面比传统的VSG具有更好的效果。更多还原

【Abstract】 In the islanded microgrid of multi-micro source networking,the traditional virtual synchronous generator(VSG) control can improve the inertia and frequency characteristics of the system to a certain extent,in order to further optimize the transient response of frequency and power,a VSG control strategy based on frequency offset integral compensation is proposed.The control strategy integrates the frequency variation into the forward channel of the firstorder virtual inertia link to reduce the power impact caused by the load disturbance on the system,thereby suppressing power and frequency oscillation,and ensuring the control accuracy of output power steady state,speeding up the response of dynamic power and frequency and prevent its amplitude from changing too fast.At the same time,the frequency modulation coefficient is retained in the active frequency control link,so that the steady-state frequency modulation characteristics of the system are preserved.The influence of different virtual inertia and damping coefficient on the transient response of the system is further discussed by establishing the small-signal model of the networked inverter,and the setting scheme and setting method of virtual inertia and damping coefficient are provided.Finally,the effectiveness of the proposed control strategy is verified by Matlab/Simulink and dSPACE platform.The results show that the VSG control strategy based on frequency offset integral compensation has better effect than the traditional VSG in improving the system transient response characteristics.更多还原