电网电压的骤升会带来新能源发电系统并网逆变器(grid-connected inverter,GCI)控制裕度的下降,如若失控则会导致能量由电网倒灌进入逆变器进而引发直流侧过压或过流。为改善电网电压骤升对GCI所造成的暂态冲击,确保其安全并网运行,该...电网电压的骤升会带来新能源发电系统并网逆变器(grid-connected inverter,GCI)控制裕度的下降,如若失控则会导致能量由电网倒灌进入逆变器进而引发直流侧过压或过流。为改善电网电压骤升对GCI所造成的暂态冲击,确保其安全并网运行,该文提出一种GCI高电压穿越(high voltage ride-through,HVRT)控制策略。首先分析容量限制条件下GCI的电流控制能力,讨论不同电网电压骤升幅度情况下GCI的可控区。在此基础上,设计基于电网电压和发电侧负载电流信息的直流母线电压参考值自适应调节算法,以确保电网电压骤升期间GCI的可控性。最后,结合感性无功电流控制,给出GCI的HVRT方案。仿真和实验结果验证了GCI控制能力分析的正确性和所提出控制策略的有效性。展开更多
并联有源滤波器(shunt active power filter,SAPF)在主动配电网系统中应用日益广泛,提升SAPF的补偿性能成为众多学者关注和研究的热点。对直流侧电压精准稳定控制是保证SAPF补偿性能的关键。采用传统PI控制系统在非线性负载突变和电压...并联有源滤波器(shunt active power filter,SAPF)在主动配电网系统中应用日益广泛,提升SAPF的补偿性能成为众多学者关注和研究的热点。对直流侧电压精准稳定控制是保证SAPF补偿性能的关键。采用传统PI控制系统在非线性负载突变和电压跳变时无法对直流侧电压进行快速稳定控制,为改善直流侧电压的控制性能,提出电压外环滑模变结构PI复合控制器。仿真与实验结果表明:滑模PI复合控制器提高了直流电压控制的稳态精度和响应速度,降低了直流电压波动对SAPF补偿性能的影响。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
文摘电网电压的骤升会带来新能源发电系统并网逆变器(grid-connected inverter,GCI)控制裕度的下降,如若失控则会导致能量由电网倒灌进入逆变器进而引发直流侧过压或过流。为改善电网电压骤升对GCI所造成的暂态冲击,确保其安全并网运行,该文提出一种GCI高电压穿越(high voltage ride-through,HVRT)控制策略。首先分析容量限制条件下GCI的电流控制能力,讨论不同电网电压骤升幅度情况下GCI的可控区。在此基础上,设计基于电网电压和发电侧负载电流信息的直流母线电压参考值自适应调节算法,以确保电网电压骤升期间GCI的可控性。最后,结合感性无功电流控制,给出GCI的HVRT方案。仿真和实验结果验证了GCI控制能力分析的正确性和所提出控制策略的有效性。
文摘并联有源滤波器(shunt active power filter,SAPF)在主动配电网系统中应用日益广泛,提升SAPF的补偿性能成为众多学者关注和研究的热点。对直流侧电压精准稳定控制是保证SAPF补偿性能的关键。采用传统PI控制系统在非线性负载突变和电压跳变时无法对直流侧电压进行快速稳定控制,为改善直流侧电压的控制性能,提出电压外环滑模变结构PI复合控制器。仿真与实验结果表明:滑模PI复合控制器提高了直流电压控制的稳态精度和响应速度,降低了直流电压波动对SAPF补偿性能的影响。
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.
