This paper demonstrates the controlling abilities of a large PV-farm as a Solar-PV inverter for mitigating the chaotic electrical,electromechanical,and torsional oscillations including Subsynchronous resonance in a tu...This paper demonstrates the controlling abilities of a large PV-farm as a Solar-PV inverter for mitigating the chaotic electrical,electromechanical,and torsional oscillations including Subsynchronous resonance in a turbogenerator-based power system.The oscillations include deviations in the machine speed,rotor angle,voltage fluctuations(lead-ing to voltage collapse),and torsional modes.During the night with no solar power generation,the PV-plant switches to PV-STATCOM mode and works as a Solar-PV inverter at its full capacity to attenuate the oscillations.During full sun in the daytime,on any fault detection,the PV-plant responds instantly and stops generating power to work as a Solar-PV inverter.The PV-farm operates in the same mode until the oscillations are fully alleviated.This paper mani-fests the control of the DC-link capacitor voltage of the Solar-PV inverter with a bacterial foraging optimization-based intelligent maximum power point tracking controller for the optimal control of active and reactive power.Kundur’s multi-machine model aggregated with PV-plant is modeled in the Matlab/Simulink environment to examine the rotor swing deviations with associated shaft segments.The results for different test cases of interest demonstrate the posi-tive outcomes of deploying large PV-farms as a smart PV-STATCOM for controlling power system oscillations.展开更多
文摘为了提高光伏并网系统的低压穿越(Low Voltage Ride Through,LVRT)能力,将储能系统(Energy Storage System,ESS)和静止同步补偿器(Static Synchronous Compensator,STATCOM)组成新型功率补偿装置STATCOM/ESS引入光伏并网发电系统。当电网侧发生电压跌落时,STATCOM/ESS不但提供的无功功率可以支撑并网点电压,同时吸收多余的有功功率避免对光伏发电系统的危害,电压恢复后将储存的能量返送回电网,高效利用能源。为便于功率双向流动,STATCOM与ESS之间采用双有源主动桥(Dual Active Bridge,DAB)直流变换器连接。针对DAB变换器,提出一种改进的双移相控制策略,来减小DAB变换器的回流功率。仿真结果表明,提出的控制策略在一定范围内将回流功率限制为零,显著提升光伏并网系统的低压穿越能力,提高光伏并网系统的稳定性,具有良好的灵活性和优越性。
文摘This paper demonstrates the controlling abilities of a large PV-farm as a Solar-PV inverter for mitigating the chaotic electrical,electromechanical,and torsional oscillations including Subsynchronous resonance in a turbogenerator-based power system.The oscillations include deviations in the machine speed,rotor angle,voltage fluctuations(lead-ing to voltage collapse),and torsional modes.During the night with no solar power generation,the PV-plant switches to PV-STATCOM mode and works as a Solar-PV inverter at its full capacity to attenuate the oscillations.During full sun in the daytime,on any fault detection,the PV-plant responds instantly and stops generating power to work as a Solar-PV inverter.The PV-farm operates in the same mode until the oscillations are fully alleviated.This paper mani-fests the control of the DC-link capacitor voltage of the Solar-PV inverter with a bacterial foraging optimization-based intelligent maximum power point tracking controller for the optimal control of active and reactive power.Kundur’s multi-machine model aggregated with PV-plant is modeled in the Matlab/Simulink environment to examine the rotor swing deviations with associated shaft segments.The results for different test cases of interest demonstrate the posi-tive outcomes of deploying large PV-farms as a smart PV-STATCOM for controlling power system oscillations.
