基于双单元柔性直流背靠背输电系统(back-to-back flexible DC transmission system,DC-BTB)两侧为同步交流电网的应用场景,提出一种根据DC-BTB两侧交流电网电压幅值和相角的变化自动调整DC-BTB有功功率的自动角差控制方法。针对双单元D...基于双单元柔性直流背靠背输电系统(back-to-back flexible DC transmission system,DC-BTB)两侧为同步交流电网的应用场景,提出一种根据DC-BTB两侧交流电网电压幅值和相角的变化自动调整DC-BTB有功功率的自动角差控制方法。针对双单元DC-BTB结构,提出单元间有功功率分配方法,研究自动角差控制下单元闭锁和交流故障的暂态特性。在实时数字仿真(real time digital simulation,RTDS)系统中搭建双单元DC-BTB模型进行仿真分析,结果表明自动角差控制稳态下功能投退冲击小,单元闭锁或交流故障穿越后能维持系统稳定运行。仿真结果验证了所提控制方法的有效性。展开更多
A single machine-infinite-bus(SMIB) system including the interline power flow controllers(IPFCs) and the power system stabilizer(PSS) controller is addressed. The linearized system model is considered for investigatin...A single machine-infinite-bus(SMIB) system including the interline power flow controllers(IPFCs) and the power system stabilizer(PSS) controller is addressed. The linearized system model is considered for investigating the interactions among IPFC and PSS controllers. To improve the stability of whole system again different disturbances, a lead-lag controller is considered to produce supplementary signal. The proposed supplementary controller is implemented to improve the damping of the power system low frequency oscillations(LFOs). Imperialist optimization algorithm(ICA) and shuffled frog leaping algorithm(SFLA) are implemented to search for optimal supplementary controllers and PSS parameters. Moreover, singular value decomposition(SVD) method is utilized to select the most effective damping control signal of IPFC lead-lag controllers. To evaluate the system performance, different operating conditions are considered. Reponses of system in five modes including uncoordinated and coordinated modes of IPFC and PSS using ICA and SFLA are studied and compared. Considering the results, response of system without controller shows the highest overshoot and the longest settling time for rotor angel at the different operating conditions. In this mode of system, rotor speed has the highest overshoot. Rotor angel in the system with only PSS includes lower overshoot and oscillation than system without controller. When PSS is only implemented, rotor speed deviation has the longest settling time. Rotor speed deviation in the uncoordinated mode of IPFC and PSS shows lower overshoot than system with only PSS and without controller. It is noticeable that in this mode, rotor angel has higher overshoot than system with only PSS. The superiority of the suggested ICA-based coordinated controllers is obvious compared with SFLA-based coordinated controllers and other system modes. Responses of coordinated PSS and IPFC SFLA-based supplementary controllers include higher peak amplitude and longer settling time compared with coordinated IPFC and PSS ICA-based controllers. This comparison shows that overshoots, undershoots and the settling times are reduced considerably in coordinated mode of IPFC based controller and PSS using ICA. Analysis of the system performance shows that the proposed method has excellent response to different faults in power system.展开更多
文摘基于双单元柔性直流背靠背输电系统(back-to-back flexible DC transmission system,DC-BTB)两侧为同步交流电网的应用场景,提出一种根据DC-BTB两侧交流电网电压幅值和相角的变化自动调整DC-BTB有功功率的自动角差控制方法。针对双单元DC-BTB结构,提出单元间有功功率分配方法,研究自动角差控制下单元闭锁和交流故障的暂态特性。在实时数字仿真(real time digital simulation,RTDS)系统中搭建双单元DC-BTB模型进行仿真分析,结果表明自动角差控制稳态下功能投退冲击小,单元闭锁或交流故障穿越后能维持系统稳定运行。仿真结果验证了所提控制方法的有效性。
文摘A single machine-infinite-bus(SMIB) system including the interline power flow controllers(IPFCs) and the power system stabilizer(PSS) controller is addressed. The linearized system model is considered for investigating the interactions among IPFC and PSS controllers. To improve the stability of whole system again different disturbances, a lead-lag controller is considered to produce supplementary signal. The proposed supplementary controller is implemented to improve the damping of the power system low frequency oscillations(LFOs). Imperialist optimization algorithm(ICA) and shuffled frog leaping algorithm(SFLA) are implemented to search for optimal supplementary controllers and PSS parameters. Moreover, singular value decomposition(SVD) method is utilized to select the most effective damping control signal of IPFC lead-lag controllers. To evaluate the system performance, different operating conditions are considered. Reponses of system in five modes including uncoordinated and coordinated modes of IPFC and PSS using ICA and SFLA are studied and compared. Considering the results, response of system without controller shows the highest overshoot and the longest settling time for rotor angel at the different operating conditions. In this mode of system, rotor speed has the highest overshoot. Rotor angel in the system with only PSS includes lower overshoot and oscillation than system without controller. When PSS is only implemented, rotor speed deviation has the longest settling time. Rotor speed deviation in the uncoordinated mode of IPFC and PSS shows lower overshoot than system with only PSS and without controller. It is noticeable that in this mode, rotor angel has higher overshoot than system with only PSS. The superiority of the suggested ICA-based coordinated controllers is obvious compared with SFLA-based coordinated controllers and other system modes. Responses of coordinated PSS and IPFC SFLA-based supplementary controllers include higher peak amplitude and longer settling time compared with coordinated IPFC and PSS ICA-based controllers. This comparison shows that overshoots, undershoots and the settling times are reduced considerably in coordinated mode of IPFC based controller and PSS using ICA. Analysis of the system performance shows that the proposed method has excellent response to different faults in power system.
