In general,the power distribution of a parallel inverter is achieved by the use of droop control in a microgrid system,which consists of PV inverters and non-regeneration energy source inverters without energy storage...In general,the power distribution of a parallel inverter is achieved by the use of droop control in a microgrid system,which consists of PV inverters and non-regeneration energy source inverters without energy storage devices in an islanded mode.If the shared load power is no more than the available maximum PV inverter output power,then there is a power waste for the PV inverter.In addition,due to the intermittency of PV sources,the system may become unstable if the shared load power is more than the available maximum power output of the PV(MPO-PV)inverter.Therefore,in order to avoid power waste and potential instability caused by insufficient PV power by traditional droop control,this paper recommends an improved droop control scheme to maximize the power output of PV units.As required by the load,the remaining power is composed of the other inverters,which can effectively improve the utilization rating of renewable energy sources and system stability.At the same time,according to the system stability analysis based on small signal modeling,it has been designed around the droop coefficients of the improved droop control loop.In the end,the simulation and experimental results show that the suggested scheme has a varied validity and robustness.展开更多
逆变器串并联型微电网吸收了传统并联型和串联型系统的优点,但其结构的复杂性给系统的控制策略设计带来了新的挑战。针对逆变器并联型和串联型微电网功率均分策略之间的矛盾,提出了一种基于虚拟阻抗技术的本地主从协调控制策略。该控制...逆变器串并联型微电网吸收了传统并联型和串联型系统的优点,但其结构的复杂性给系统的控制策略设计带来了新的挑战。针对逆变器并联型和串联型微电网功率均分策略之间的矛盾,提出了一种基于虚拟阻抗技术的本地主从协调控制策略。该控制策略将每个微源串中靠近公共连接点(Point of Common Coupling, PCC)的微源设置为主控单元,其采用无通信的改进下垂控制实现微源串之间的同步和功率一致,其余串联微源在本地跟随主控单元运行,最终实现了全局的功率均分。全局无通信的设计提高了系统的可靠性和灵活性,降低了运行成本。仿真结果验证了所提方案的可行性和有效性。展开更多
文摘In general,the power distribution of a parallel inverter is achieved by the use of droop control in a microgrid system,which consists of PV inverters and non-regeneration energy source inverters without energy storage devices in an islanded mode.If the shared load power is no more than the available maximum PV inverter output power,then there is a power waste for the PV inverter.In addition,due to the intermittency of PV sources,the system may become unstable if the shared load power is more than the available maximum power output of the PV(MPO-PV)inverter.Therefore,in order to avoid power waste and potential instability caused by insufficient PV power by traditional droop control,this paper recommends an improved droop control scheme to maximize the power output of PV units.As required by the load,the remaining power is composed of the other inverters,which can effectively improve the utilization rating of renewable energy sources and system stability.At the same time,according to the system stability analysis based on small signal modeling,it has been designed around the droop coefficients of the improved droop control loop.In the end,the simulation and experimental results show that the suggested scheme has a varied validity and robustness.
文摘逆变器串并联型微电网吸收了传统并联型和串联型系统的优点,但其结构的复杂性给系统的控制策略设计带来了新的挑战。针对逆变器并联型和串联型微电网功率均分策略之间的矛盾,提出了一种基于虚拟阻抗技术的本地主从协调控制策略。该控制策略将每个微源串中靠近公共连接点(Point of Common Coupling, PCC)的微源设置为主控单元,其采用无通信的改进下垂控制实现微源串之间的同步和功率一致,其余串联微源在本地跟随主控单元运行,最终实现了全局的功率均分。全局无通信的设计提高了系统的可靠性和灵活性,降低了运行成本。仿真结果验证了所提方案的可行性和有效性。
