摘要
在一个开关周期内将电网电压ugrid作为时变量建立数字控制H6结构不隔离并网逆变器(DNGI-H6)的离散模型。针对占空比和状态变量之间存在一个开关周期延时,离散迭代模型中的状态变量不相互独立,导致Jacobian矩阵计算复杂的问题,引入新的状态变量,避免复杂的高阶矩阵运算,简化Jacobian矩阵的求解过程,并推导DNGI-H6的稳定边界和振荡频率的数学表述。最后,通过仿真和实验验证离散模型的正确性和稳定性分析新方法的可行性。
The exact-discrete model of digital-controlled non-isolated grid-connected inverter with H6-type(DNGI-H6)is firstly established by taking grid voltage ugrid as a time variable in a switching cycle.Due to one switching cycle delay between the duty cycle and the state variables of the DNGI-H6 system,the state variables of the discrete iterative equation are not independent of each other,which makes it hard to get the Jacobian matrix directly.By introducing a new state variable,the new method can avoid the complex calculation of high-order matrix,which simplifies the calculation process of Jacobian matrix.And the stability boundary and oscillation frequency are described.Finally,the accuracy of the discrete model and the feasibility of the new stability analysis method are demonstrated by the simulation and experimental results.
作者
陈禹希
庄圣贤
代云中
曾蕊
周春华
Chen Yuxi;Zhuang Shengxian;Dai Yunzhong;Zeng Rui;Zhou Chunhua(School of Electrical Engineering,Southwest Jiaotong University,Chengdu 611756,China;School of Electrical Engineering,Southwest Petroleum University,Chengdu 610500,China)
出处
《太阳能学报》
EI
CAS
CSCD
北大核心
2020年第6期178-187,共10页
Acta Energiae Solaris Sinica
基金
国家重点研发计划(2016YFF0203400)。
关键词
数字控制
延时
稳定性分析
时变系统
离散建模
振荡频率
digital control
time delay
stability analysis
time varying systems
discrete modeling
oscillation
