This paper presents a unified positive-and negative-sequence dual-dq dynamic model of wind-turbine driven doubly-fed induction generator(DFIG) under unbalanced grid voltage conditions. Strategies for enhanced control ...This paper presents a unified positive-and negative-sequence dual-dq dynamic model of wind-turbine driven doubly-fed induction generator(DFIG) under unbalanced grid voltage conditions. Strategies for enhanced control and operation of a DFIG-used back-to-back(BTB) PWM voltage source converter(VSC) are proposed. The modified control design for the grid-side converter in the stationary αβ frames diminishes the amplitude of DC-link voltage ripples of twice the grid frequency,and the two proposed control targets for the rotor-side converter are alternatively achieved,which,as a result,improve the fault-ride through(FRT) capability of the DFIG based wind power generation systems during unbalanced network supply. A complete unbalanced control scheme with both grid-and rotor-side converters included is designed. Finally,simulation was carried out on a 1.5 MW wind-turbine driven DFIG system and the validity of the developed unified model and the feasibility of the proposed control strategies are all confirmed by the simulated results.展开更多
This paper proposes an indirect power control of doubly fed induction generator （DFIG） with the rotor connected to the electric grid through a back-to-back pulse width modulation （PWM） converter for variable speed...This paper proposes an indirect power control of doubly fed induction generator （DFIG） with the rotor connected to the electric grid through a back-to-back pulse width modulation （PWM） converter for variable speed wind power generation. Appropriate state space model of the DFIG is deduced. An original control strategy based on a variable structure control theory, also called sliding mode control, is applied to achieve the control of the active and reactive power exchanged between the stator of the DFIG and the grid. A proportional-integral-（P1） controller is used to keep the DC-link voltage constant for a back-to-back PWM converter. Simulations are conducted for validation of the digital controller operation using Matlab/Simulink software.展开更多
背靠背直流输电可以实现不同供区的柔性互联,基于模块化多电平换流器的电池储能系统(modular multi-level converter based battery energy storage system,MMC-BESS)的换流站还可以起到配合新能源接入、对交直流功率进行平抑及缓冲的...背靠背直流输电可以实现不同供区的柔性互联,基于模块化多电平换流器的电池储能系统(modular multi-level converter based battery energy storage system,MMC-BESS)的换流站还可以起到配合新能源接入、对交直流功率进行平抑及缓冲的作用。以厦门同吉开关站新型配电网示范工程为背景,其两端换流站采用MMC-BESS和基于模块化多电平换流器的中压柔性直流输电(MMC based medium voltage direct current,MMC-MVDC),背靠背实现了2条10 kV交流线路的柔性互联。针对该工程运行控制策略进行了分析和仿真研究,验证了控制策略的有效性,以及关键部件的状态在合理的范围内,对实际工程的设计和运行具有一定的指导意义。展开更多
基金Project (No. 50577056) supported by the National Natural ScienceFoundation of China
文摘This paper presents a unified positive-and negative-sequence dual-dq dynamic model of wind-turbine driven doubly-fed induction generator(DFIG) under unbalanced grid voltage conditions. Strategies for enhanced control and operation of a DFIG-used back-to-back(BTB) PWM voltage source converter(VSC) are proposed. The modified control design for the grid-side converter in the stationary αβ frames diminishes the amplitude of DC-link voltage ripples of twice the grid frequency,and the two proposed control targets for the rotor-side converter are alternatively achieved,which,as a result,improve the fault-ride through(FRT) capability of the DFIG based wind power generation systems during unbalanced network supply. A complete unbalanced control scheme with both grid-and rotor-side converters included is designed. Finally,simulation was carried out on a 1.5 MW wind-turbine driven DFIG system and the validity of the developed unified model and the feasibility of the proposed control strategies are all confirmed by the simulated results.
文摘This paper proposes an indirect power control of doubly fed induction generator （DFIG） with the rotor connected to the electric grid through a back-to-back pulse width modulation （PWM） converter for variable speed wind power generation. Appropriate state space model of the DFIG is deduced. An original control strategy based on a variable structure control theory, also called sliding mode control, is applied to achieve the control of the active and reactive power exchanged between the stator of the DFIG and the grid. A proportional-integral-（P1） controller is used to keep the DC-link voltage constant for a back-to-back PWM converter. Simulations are conducted for validation of the digital controller operation using Matlab/Simulink software.
文摘背靠背直流输电可以实现不同供区的柔性互联,基于模块化多电平换流器的电池储能系统(modular multi-level converter based battery energy storage system,MMC-BESS)的换流站还可以起到配合新能源接入、对交直流功率进行平抑及缓冲的作用。以厦门同吉开关站新型配电网示范工程为背景,其两端换流站采用MMC-BESS和基于模块化多电平换流器的中压柔性直流输电(MMC based medium voltage direct current,MMC-MVDC),背靠背实现了2条10 kV交流线路的柔性互联。针对该工程运行控制策略进行了分析和仿真研究,验证了控制策略的有效性,以及关键部件的状态在合理的范围内,对实际工程的设计和运行具有一定的指导意义。
