摘要
针对含虚拟惯量的双馈风电并网系统振荡稳定问题,从动态能量的角度揭示了虚拟惯量对双馈风电机组(doubly fed induction generator,DFIG)参与系统振荡的作用机理。首先,构建了不同振荡模态下含虚拟惯量双馈风电机组的动态能量模型,并探究了虚拟惯量直接和间接通过锁相环影响机网耦合的能量通道。在此基础上,定义了耗散强度指标,表征双馈风电机组对各振荡模态的耗散作用,并分析了不同接入位置、不同控制参数、不同振荡模态下虚拟惯量通过各能量通道对双馈风电机组耗散强度以及机网耦合作用的影响,揭示了含虚拟惯量风电机组与网侧能量交互诱使系统振荡发散的作用机理。最后,以IEEE四机两区系统进行实时数字仿真(Real Time Digital Simulator,RTDS)仿真验证,结果表明:当锁相环(phase-locked-loop,PLL)自激振荡模态与网侧机电振荡模态频率相距较远时,含虚拟惯量风机接入送端区域产生负耗散作用,接入受端区域产生正耗散作用。当PLL自激振荡模态与网侧机电振荡模态频率接近时,受模态强耦合共振影响,风机通过锁相环自耦合能量通道和虚拟惯量能量通道与电网强交互,产生负耗散作用,且在模态频率重合时达到极大值。
The mechanism of virtual inertia control on doubly fed induction generator(DFIG)participating in low frequency oscillation was revealed from the perspective of dynamic energy.First,the dynamic energy model of DFIG with virtual inertia control under different oscillation modes was derived,and the energy channel where virtual inertia directly and indirectly affects the coupling between generator and network through phase-locked-loop(PLL)was explored.On this basis,the dissipation intensity was defined,which characterized the dissipation effect of DFIG on each oscillation mode.Besides,the influence of virtual inertia control on the dissipation intensity and the coupling effect between DFIG and the grid through each energy channel under different locations,control parameters and oscillation modes were analyzed.Thus,the mechanism of energy interaction between DFIG with virtual inertia and grid to induce system oscillation divergence was further revealed.Finally,simulation tests with real time digital simulator(RTDS)of the IEEE 4-machine 2-area system verify that,when the PLL self-excited oscillation frequency is far from electromechanical oscillation frequency,the DFIG with virtual inertia control connecting to the sending area has a negative dissipation effect,while the one connecting to the receiver area has a positive dissipation effect.When the PLL self-excited oscillation frequency is close to electromechanical oscillation frequency,due to the strong coupling resonance between them,DFIG interacts strongly with the grid through the PLL self-coupling energy channel and virtual inertia energy channel.In this case,DFIG has a negative dissipation effect in both sending and receiving areas,and the effect reaches the maximum when they overlap.
作者
沈雅琦
马静
SHEN Yaqi;MA Jing(State Key Laboratory of Alternate Electric Power Systems With New Energy Resources(North China Electric Power University),Changping District,Beijing 102206,China)
出处
《中国电机工程学报》
EI
CSCD
北大核心
2022年第15期5506-5522,共17页
Proceedings of the CSEE
基金
国家自然科学基金项目(51777070)。
关键词
双馈风电机组
虚拟惯量控制
动态能量
机网耦合
锁相环
机电振荡
耗散强度
doubly fed induction generator(DFIG)
virtual inertia control
dynamic energy
coupling between DFIG and grid
phase-locked-loop(PLL)
electromechanical oscillation
dissipation intensity
