In the modern power system, both local and centralized reactive power control strategies for photovoltaic(PV) plants, are proposed and compared. While local control improves the network security, it lacks the optimiza...In the modern power system, both local and centralized reactive power control strategies for photovoltaic(PV) plants, are proposed and compared. While local control improves the network security, it lacks the optimization benefits from centralized control strategies.Therefore, this paper considers the coordination of the two control strategies, depending on external impact from the weather system and consumer behavior, in a low voltage(LV) distribution feeder. Through modeling and simulation in an established real-time cyber-physical simulation platform, the LV network is evaluated with both local and centralized control. A set of boundaries for coordinating between the two strategies are identified, which can help network operators decide suitable control in different operating situations. Furthermore, the cyber-physical simulation platform, is used to study the impact of physical perturbations, i.e. changes in irradiance and consumption,and cyber disturbances, in form of communication channel noise, is evaluated for the control strategies. Results show how small and large disturbances in the cyber system affect the centralized control strategy optimizer performance.展开更多
The dynamic characteristics of converter-dominated systems are governed by controlling power converters and the interactions between converter systems and conventional alternators.Frequency oscillations can appear und...The dynamic characteristics of converter-dominated systems are governed by controlling power converters and the interactions between converter systems and conventional alternators.Frequency oscillations can appear under dynamic operation conditions caused by the phase-locked loop dynamics and interactions among the converter control systems.The oscillations may be poorly damped,which can result in reduced power generation,longer settling time,or disconnections of sensitive components.It is foreseeable that damping services will be critical for power grid stabilization in the future with high penetration of renewable generation.In this work,synchronous condensers(SCs)are evaluated and applied to provide damping services to the power grid under post-event conditions.An innovative supplementary controller for the automatic voltage regulator of SCs is proposed to improve the frequency stabilization in a converter-dominated system after disturbances.Using local and remote measurements,SCs are able to modulate the reactive power output and hence,the terminal bus voltage,which further impacts the power flow in the system;therefore,damping can be provided to the frequency oscillations.The control is implemented on an industrial-level hardware platform,and the performance is verified by the hardware-in-the-loop simulation.展开更多
文摘In the modern power system, both local and centralized reactive power control strategies for photovoltaic(PV) plants, are proposed and compared. While local control improves the network security, it lacks the optimization benefits from centralized control strategies.Therefore, this paper considers the coordination of the two control strategies, depending on external impact from the weather system and consumer behavior, in a low voltage(LV) distribution feeder. Through modeling and simulation in an established real-time cyber-physical simulation platform, the LV network is evaluated with both local and centralized control. A set of boundaries for coordinating between the two strategies are identified, which can help network operators decide suitable control in different operating situations. Furthermore, the cyber-physical simulation platform, is used to study the impact of physical perturbations, i.e. changes in irradiance and consumption,and cyber disturbances, in form of communication channel noise, is evaluated for the control strategies. Results show how small and large disturbances in the cyber system affect the centralized control strategy optimizer performance.
基金This work was supported by Synchronous Condenser Application(SCAPP)project funded by ForskEL program(No.12196)administrated by Energinet.dk.
文摘The dynamic characteristics of converter-dominated systems are governed by controlling power converters and the interactions between converter systems and conventional alternators.Frequency oscillations can appear under dynamic operation conditions caused by the phase-locked loop dynamics and interactions among the converter control systems.The oscillations may be poorly damped,which can result in reduced power generation,longer settling time,or disconnections of sensitive components.It is foreseeable that damping services will be critical for power grid stabilization in the future with high penetration of renewable generation.In this work,synchronous condensers(SCs)are evaluated and applied to provide damping services to the power grid under post-event conditions.An innovative supplementary controller for the automatic voltage regulator of SCs is proposed to improve the frequency stabilization in a converter-dominated system after disturbances.Using local and remote measurements,SCs are able to modulate the reactive power output and hence,the terminal bus voltage,which further impacts the power flow in the system;therefore,damping can be provided to the frequency oscillations.The control is implemented on an industrial-level hardware platform,and the performance is verified by the hardware-in-the-loop simulation.