The increasing penetration of wind power presents many technical challenges to power system operations. An important challenge is the need of voltage control to maintain the terminal voltage of a wind plant to make it...The increasing penetration of wind power presents many technical challenges to power system operations. An important challenge is the need of voltage control to maintain the terminal voltage of a wind plant to make it a PV bus like conventional generators with excitation control. In the previous work for controlling wind plant, especially the Doubly Fed Induction Generator (DFIG) system, the proportional-integral (PI) controllers are popularly applied. These approaches usually need to tune the PI controllers to obtain control gains as a tradeoff or compromise among various operating conditions. In this paper, a new voltage control approach based on a different philosophy is presented. In the proposed approach, the PI control gains for the DFIG system are dynamically adjusted based on the dynamic, continuous sensitivity which essentially indicates the dynamic relationship between the change of control gains and the desired output voltage. Hence, this control approach does not require any good estimation of fixed control gains because it has the self-learning mechanism via the dynamic sensitivity. This also gives the plug-and-play feature of DFIG controllers to make it promising in utility practices. Simulation results verify that the proposed approach performs as expected under various operating conditions.展开更多
This paper describes a stabilization effect after installating an adjustable speed generator (ASG) in a multi machine power system. A personal computer based ASG module has been de veloped for the simulations in...This paper describes a stabilization effect after installating an adjustable speed generator (ASG) in a multi machine power system. A personal computer based ASG module has been de veloped for the simulations in parallel with the analog power system simulator i n the Research Laboratory of the Kyushu Electric Power Co. The three phase ins t antaneous value based ASG model has been developed in the Matlab/Simulink envir onment for its detailed and real time simulations, which have been performed on a digital signal processor (DSP) board with AD and DA conversion interfaces inst alled in a personal computer (PC). Simulational results indicate the hig hly improved overall stability of the multi machine power system after installa ting the ASG.展开更多
随着出力具有随机波动性特征的分布式电源渗透率的不断攀升以及城市电缆化率的进程加速,有源配电网线路中无功过剩和过电压的现象日益明显,对动态无功补偿装置的经济性、可靠性和精准调控能力提出更高要求。在电流源型静止同步补偿器的...随着出力具有随机波动性特征的分布式电源渗透率的不断攀升以及城市电缆化率的进程加速,有源配电网线路中无功过剩和过电压的现象日益明显,对动态无功补偿装置的经济性、可靠性和精准调控能力提出更高要求。在电流源型静止同步补偿器的基础上,该文结合双旋转移相变压器的连续调节特性,提出一种新型旋转式无功补偿器(novel rotary var compensator,NRVC)拓扑电路。通过构建NRVC稳态数学模型,深入分析得到NRVC补偿调控机理及其补偿容量约束关系。针对NRVC结构特点,提出基于瞬时无功理论的无功补偿控制策略,其中功率外环可对功率因数进行精确控制,电流内环加入限幅环节有效限流,提高装置运行可靠性。通过仿真及动模实验验证所提拓扑及其控制策略的有效性,结果验证了NRVC具备双向、连续调节补偿无功的能力,具有调节精度高、谐波畸变率低的优点。展开更多
文摘The increasing penetration of wind power presents many technical challenges to power system operations. An important challenge is the need of voltage control to maintain the terminal voltage of a wind plant to make it a PV bus like conventional generators with excitation control. In the previous work for controlling wind plant, especially the Doubly Fed Induction Generator (DFIG) system, the proportional-integral (PI) controllers are popularly applied. These approaches usually need to tune the PI controllers to obtain control gains as a tradeoff or compromise among various operating conditions. In this paper, a new voltage control approach based on a different philosophy is presented. In the proposed approach, the PI control gains for the DFIG system are dynamically adjusted based on the dynamic, continuous sensitivity which essentially indicates the dynamic relationship between the change of control gains and the desired output voltage. Hence, this control approach does not require any good estimation of fixed control gains because it has the self-learning mechanism via the dynamic sensitivity. This also gives the plug-and-play feature of DFIG controllers to make it promising in utility practices. Simulation results verify that the proposed approach performs as expected under various operating conditions.
文摘This paper describes a stabilization effect after installating an adjustable speed generator (ASG) in a multi machine power system. A personal computer based ASG module has been de veloped for the simulations in parallel with the analog power system simulator i n the Research Laboratory of the Kyushu Electric Power Co. The three phase ins t antaneous value based ASG model has been developed in the Matlab/Simulink envir onment for its detailed and real time simulations, which have been performed on a digital signal processor (DSP) board with AD and DA conversion interfaces inst alled in a personal computer (PC). Simulational results indicate the hig hly improved overall stability of the multi machine power system after installa ting the ASG.
文摘随着出力具有随机波动性特征的分布式电源渗透率的不断攀升以及城市电缆化率的进程加速,有源配电网线路中无功过剩和过电压的现象日益明显,对动态无功补偿装置的经济性、可靠性和精准调控能力提出更高要求。在电流源型静止同步补偿器的基础上,该文结合双旋转移相变压器的连续调节特性,提出一种新型旋转式无功补偿器(novel rotary var compensator,NRVC)拓扑电路。通过构建NRVC稳态数学模型,深入分析得到NRVC补偿调控机理及其补偿容量约束关系。针对NRVC结构特点,提出基于瞬时无功理论的无功补偿控制策略,其中功率外环可对功率因数进行精确控制,电流内环加入限幅环节有效限流,提高装置运行可靠性。通过仿真及动模实验验证所提拓扑及其控制策略的有效性,结果验证了NRVC具备双向、连续调节补偿无功的能力,具有调节精度高、谐波畸变率低的优点。