摘要
提出了一种基于同步发电机机电暂态模型的新型微电网逆变电源(称为虚拟同步发电机)。功率控制器和电压频率控制器使该逆变电源具有功率控制和调频调压双重功能,而且在微电网发生故障时仍能作为不间断电源向重要负荷供电,预并列单元则使得该逆变电源能够可靠并联到微电网上;当微电网连接大电网运行时,系统频率由大电网决定,各虚拟同步发电机可采用功率控制策略使其按照功率调度指令输出功率。当微电网孤岛运行时,必须有逆变单元采用电压频率控制策略,提供微电网的电压参考;微电网中,同等容量的逆变电源还可以任意替换,易于模块化、标准化生产,增加了微电网控制的灵活性,提高了系统的可靠性。所提出的控制策略已在MATLAB/Simulink上得到验证。
A new inverter based on the electromechanical transient model of synchronous generator （which is referred to as virtual synchronous generator） is presented. A power controller and a voltage-frequency controller are designed to make the inverter with double function of controlling power and modulating frequency and voltage. Furthermore, when microgrid is faulty, uninterruptable electrical power can still be supplied to important loads of the microgrid. A pre-grid unit designed enables safe connection of the inverter and a microgrid. When the microgrid connecting with the main grid, frequency is decided by the main grid, so power control strategy is employed in each virtual synchronous generator to control its dispatchable output power. When the microgrid is islanding, voltage reference should be provided by one inverter using voltage-frequency controller. In addition, it is convenient to be modularized and standardized because virtual synchronous generator with the same capacity can be replaced freely in the microgrid. This scheme will increase the flexibility of microgrid and enhance the reliability of system control strategy, which has been verified by the MATLAB/Simulink.
出处
《电力系统自动化》
EI
CSCD
北大核心
2009年第8期89-93,共5页
Automation of Electric Power Systems
基金
国家自然科学基金资助项目(50777015
50837001)
国家高技术研究发展计划(863计划)资助项目(2007AA05Z240)~~
关键词
微电网
虚拟同步发电机
调频调压
功率控制
预并列单元
microgrid
virtual synchronous generator
frequency and voltage regulation
power control
pre-grid unit
