摘要
当并网逆变器(机组)接入弱电网时,电网阻抗的宽范围变化可能会导致系统不稳定。为此,通过在公共耦合点(PCC)处并联集中式有源阻尼装置,使其模拟阻尼电阻的外特性,可实现对并网逆变器与电网之间的谐振的抑制。此处提出一种基于有源阻尼装置的虚拟电阻值自适应调节方法,既保证系统稳定性,又使有源阻尼装置中流过的电流尽可能小。同时,此处还提出一种对电流谐波基准的补偿方法,能够减小电流闭环对虚拟阻抗特性的影响,进一步改进阻尼效果。通过在实验室搭建一台5 kW的并网逆变器和一个1 kVA的有源阻尼装置,验证了所提控制方案的有效性。
When a grid-connected inverter is connected to a weak grid,the system may be instable.Therefore,an active damping device,which synthesizes a damping resistor at the harmonic frequencies,can be connected to the point of common coupling(PCC) to damp the resonance and thus stabilize the system.An adaptive tuning method of the virtual resistor is proposed,which can ensure the system stability while minimizing the port current of the active damper.Besides,to avoid the influence of the current loop on the characteristic of the virtual resistor,a compensation method for the harmonic current reference is proposed.The prototypes of a 5 kW grid-connected inverter and a 1 kVA active damping device are built and tested to verify the effectiveness of the proposed control scheme.
作者
刘冬梅
谢吉华
俞斌
LIU Dong-mei;XIE Ji-hua;YU Bin(Yangzhou Polytechnic College,Yangzhou 225009,China;不详)
出处
《电力电子技术》
CSCD
北大核心
2022年第7期54-57,共4页
Power Electronics
基金
国网公司总部科技项目(524608180092)。
关键词
并网逆变器
弱电网
稳定性
有源阻尼装置
grid-connected inverter
weak grid
stability
active damping device
