考虑多控制环路影响的VSG型构网储能dq阻抗建模及稳定性分析  

Modeling and stability analysis of energy storage dq impedance of VSG-type configuration network considering the influence of multiple control loops

作　　者：陈建荣 赵波 赵炳洋 CHEN Jianrong;ZHAO Bo;ZHAO Bingyang(School of Automation,Beijing Information Science and Technology University,Beijing 100192,China)

机构地区：[1]北京信息科技大学自动化学院,北京100192

出　　处：《储能科学与技术》2025年第1期222-239,共18页Energy Storage Science and Technology

摘　　要：新型电力系统同步机比例的减少对系统稳定运行带来挑战,构网储能系统因具有电压源外特性和良好的弱网稳定性受到广泛关注。但构网储能本质仍是多控制环路多控制参数的电力电子设备,因此构网储能自身稳定性问题需要考虑。目前针对多环路控制的跟网储能稳定性研究较多,而构网型的稳定性研究较少。因此本工作考虑虚拟同步发电机(VSG)型构网储能主电路与功率环,从实际控制需求角度出发,进一步考虑电压环、电流环以及虚拟阻抗环,选择dq坐标系,建立多环路小信号模型与等效输出阻抗模型。接着分析了控制环路参数对不同频段阻抗特性的影响,并由阻抗法进行并网小信号稳定性分析。最后通过仿真验证。相关结果表明:VSG型构网储能在低频段(1~10 Hz)存在负阻尼特性,功率环会诱发低频负阻尼谐振频率增大,电压环则会诱发系统中频段(10~100 Hz)出现负阻尼特性,电流环则会诱发系统高频段(100~10000 Hz)出现负阻尼特性。弱电网工况下,功率环阻尼的减小与虚拟惯量的增大、电压环比例系数的减小与积分系数的增大均会引发低频振荡导致系统失稳,而电流环对系统稳定性影响小。在短路比(SCR)为2时,引入虚拟阻抗环,功率环控制参数稳定区域面积扩大约1.67倍,电压环控制参数稳定区域面积扩大约4.5倍。The reduction in the proportion of synchronous machines in the new power system brings challenges to maintaining the stable operation of the system.Consequently,the constructed-grid energy storage system has received immense attention due to its voltage source external characteristics and good weak-grid stability.Nevertheless,the nature of gridconstructed energy storage is still a power electronic device with multiple control loops and control parameters;thus,the stability of grid-constructed energy storage needs to be considered.Numerous studies have focused on the stability of multi-loop controlled energy storage,while there are fewer studies on the stability of structural network type.This paper examines the main circuit and power ring of grid-constructed energy storage using a virtual synchronous generator(VSG).We analyzed the voltage,current,and virtual impedance loops from the perspective of actual control demand,selected the dq coordinate system,and established the multi-loop small-signal and the equivalent output impedance models.Subsequently,the influence of the control loop parameters on the impedance characteristics of different frequency bands is analyzed,followed by a grid-connected small-signal stability analysis using the impedance method.Finally,these results were confirmed by simulation.The findings indicated that the VSG-type grid-connected energy storage exhibits negative damping characteristics in the low-frequency band(1—10 Hz),with the power loop inducing an elevation in the low-frequency negatively damped resonance frequency.Furthermore,the voltage loop induces negative damping characteristics in the middle-frequency band of the system(10—100 Hz),whereas the current loop induces negative damping characteristics in the high-frequency band of the system(100—10000 Hz).Under a weak grid condition,the reduction in power ring damping and the increase of virtual inertia,along with a decrease in voltage ring proportionality coefficient and an increase in integral coefficient,can induce lowfre

关 键 词：构网储能 多控制环路 dq阻抗建模 小信号稳定性 

分 类 号：TM74[电气工程—电力系统及自动化]